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View Full Version : Lathe build: Part 2, the full mockup



Evan
01-08-2009, 03:40 PM
I now have a good enough idea of what I will build to present a full mockup of the machine. This is in some parts subject to change but the basic structure will follow this mockup fairly closely.

http://metalshopborealis.ca/pics5/lathemu1.jpg

As shown the spindle center clearance over the ways is 9 inches for an 18" swing. The headstock base plate will be cut shorter. It currently weighs somewhere around 80 lbs for that plate alone. The spindle supports may be used along with heavy cast iron collars to hold the spindle cartridge or may be replaced by some other heavier material. Not shown are steel tie plates that will join the steel supports (green) to the rest of the bed. The entire machine will end up running on a custom stand with chip tray so cleanout clearance is not necessary. The drive motor will be incorporated in the stand.

http://metalshopborealis.ca/pics5/lathemu0.jpg


Details of the way system are hardened and precision ground 1040 steel shafting for the front way with partial round cast iron linear bearings. The Round way will be fully supported along it's length and the support will be embedded in a layer of epoxy on the top of the front frame. Epoxy resin is unusual in that it has the same coefficient of linear expansion as steel.

Also not seen here is a system of cross braces that will be screwed through the Jatoba beams to tie plates on the outside of each beam. The entire bed system should be extremely rigid but with good damping. The cross braces may be made from cast iron.

http://metalshopborealis.ca/pics5/lathemu2.jpg


http://metalshopborealis.ca/pics5/lathemu3.jpg

The tailstock is for visual interest only and a new more appropriate one will be constructed.

mikem
01-08-2009, 03:50 PM
I don't know that I am worthy enough to offer advice to Evan :) but my tool nut friend once told me to buy a bigger lathe for more capacity and then to just cut off the bed and remount the legs and tailstock. These big old lathes are pretty cheap to buy and the shorter bed length gives more rigidity.

tony ennis
01-08-2009, 03:59 PM
What's inappropriate about the tailstock?

Evan
01-08-2009, 04:37 PM
Mike, old used lathes are very uncommon around here. In fact any sort of used machine tool is very uncommon. I could find something in Vancouver but that is over 1000 kilometers round trip and I can't drive long distances anymore. Even then the prices for any sort of used equipment tend to be very high.


The tailstock needs to be a lot heavier.

aostling
01-08-2009, 04:56 PM
As shown the spindle center clearance over the ways is 9 inches for an 18" swing.

Evan,

I visualize you turning a barrel for a new telescope on this. Will it be a 18" Dobsonian?

lane
01-08-2009, 06:36 PM
Just make sure you use the correct bearings in the right places are all billy hell will be raised . Evan I thank it will work good.

S_J_H
01-08-2009, 06:56 PM
ahhh, I'm starting to see the whole picture now.

So will the flat way use a gib setup of some sorts? I realize the round way is the guide way. Seems like a good method that should not be to difficult setup true.

The dovetail slides will save you a lot of work from machining slides from scratch. They look nice and low profile. What are they from?

Steve

bob_s
01-08-2009, 07:28 PM
Have you given any consideration to making it a gap bed?

Evan
01-08-2009, 07:41 PM
Allan,

I don't know what my next optical project might be but a larger telescope is probably in the cards at some point. It won't be a dobsonian as I don't do much visual observing. My night vision is too poor for that because of severe astigmatism that shows up when my pupils are dilated.

Steve,

The rear way will have a gib on the underside to control lift and drag on the carriage. The slides are from a cheap POS x-y table. With some work they will be fine in this application.

Thanks Lane. I am very sure it will do what I need.

Bob, a gap bed? Whatever for? It's already going to have an 18" or so swing.

lazlo
01-08-2009, 07:52 PM
Bob, a gap bed? Whatever for? It's already going to have an 18" or so swing.

Evan, if all you need is more swing than your South Bend 9, why don't you just make a headstock riser? That's what a lot of the British Model Engineers used to do...

bob_s
01-08-2009, 07:56 PM
If you are going for big then a gap bed gives you the absolute max possible.

Doesn't an 18" reflector telescope require a somewhat larger than 18" frame

S_J_H
01-08-2009, 08:28 PM
Evan,
My old Artisan 11x24 is a gap bed. It can do 18" in the gap.
By just leaving your ways short to the head stock you could have a gap for even larger parts.
The Artisan has a feature that you might consider adding in some way to your machine.
A thrust support pad is located under the lead screw to give the carriage extra rigidity when large parts are being turned in the gap.
Here's the setup-
http://i109.photobucket.com/albums/n48/S_J_H/vintage%20Artisan%20lathe/artisan2ndway004.jpg
http://i109.photobucket.com/albums/n48/S_J_H/vintage%20Artisan%20lathe/artisan2ndway002.jpg

Steve

Evan
01-08-2009, 08:46 PM
Evan, if all you need is more swing than your South Bend 9, why don't you just make a headstock riser? That's what a lot of the British Model Engineers used to do...


It doesn't have enough power to make a cut at the circumference of a 16" part. I'll be putting at least 2hp on this machine with a serpentine belt drive that has two "gears", one of them a fairly heavy step down ratio to make best use of the torque even with a VFD. I may swap out the 3 hp 3 phase motor on my shaper. It really doesn't need that much power the way I run it. I am also considering taking the varispeed from my horizontal mill. That would really be a nice way to run this lathe.

I don't like the idea of a gap bed. I don't need it and it would weaken the lathe.

lazlo
01-08-2009, 08:51 PM
It doesn't have enough power to make a cut at the circumference of a 16" part.

Ah, that makes sense.


I am also considering taking the varispeed from my horizontal mill. That would really be a nice way to run this lathe.

Inded -- that would be sweet! I don't like the hydraulic actuation on the Reeve's drive on my Clausing, but the infinitely variable speed (with full power at all speeds) is really nice.

wierdscience
01-08-2009, 09:37 PM
Evan,
My old Artisan 11x24 is a gap bed. It can do 18" in the gap.
By just leaving your ways short to the head stock you could have a gap for even larger parts.
The Artisan has a feature that you might consider adding in some way to your machine.
A thrust support pad is located under the lead screw to give the carriage extra rigidity when large parts are being turned in the gap.
Steve

Steve,that is a nice feature,a LOT better than these sorry gap beds being made now.

wierdscience
01-08-2009, 09:40 PM
Evan,have you considered making the headstock and motor drive one unit that could be swung around 180* and used as a T-lathe when even larger swing might be needed?

A lot of the new wood lathes do that to allow outboard bowl turning.A provison to support a simple XY crossslide would not be hard to include at this stage.Just a thought.

Ken_Shea
01-08-2009, 09:43 PM
Steve,that is a nice feature,a LOT better than these sorry gap beds being made now.

Hey, I resemble that remark :D

Evan that is going to be a nice build.

When you get it done can we have a drawing and the winner gets a 15 minute all he can grab shopping spree in your stuff :D

You have more goodies around then anyone I know.

Ken

J Tiers
01-08-2009, 10:03 PM
It doesn't have enough power to make a cut at the circumference of a 16" part. I'll be putting at least 2hp on this machine with a serpentine belt drive that has two "gears", one of them a fairly heavy step down ratio to make best use of the torque even with a VFD. I may swap out the 3 hp 3 phase motor on my shaper. It really doesn't need that much power the way I run it. I am also considering taking the varispeed from my horizontal mill. That would really be a nice way to run this lathe.

I don't like the idea of a gap bed. I don't need it and it would weaken the lathe.

I suggested a riser a while back...... but there is a better idea that solves BOTH problems. Logan and others had them.

This is a spindle adapter...... essentially a de-mountable new spindle (you have that) on a carrier that is driven off the present one, mounting in front of (and somewhat over) the headstock.

Naturally, there is a gear-down in between, since you won't be wanting 1200 rpm at 18" swing, most likely in the home shop.

Example, (if the link is good):

http://flickr.com/photos/loganact/3174913310/in/set-72157612243413732/

nheng
01-08-2009, 10:08 PM
Instead of a headstock riser, how about a headstock translator.

You mount the new spindle in a compact headstock that matches your SB ways. Drive it with a timing belt and pair of mating pulleys, one mounted on an arbor installed in the spindle. The toolpost would then need to be raised up on a substantial block to compensate for its height.

Tailstock would be a BIG problem but another steady probably would not be :)

Primary limitation, of course, would be how much metal you need to remove at once. Doesn't offer much over a riser except that it COULD be made with more rigidity than one.

Den

lazlo
01-08-2009, 10:13 PM
I suggested a riser a while back...... but there is a better idea that solves BOTH problems. Logan and others had them.

http://flickr.com/photos/loganact/3174913310/in/set-72157612243413732/

"Auxiliary Head that adapts a Logan 11" to swing 14" "

Wow, that's cool! How well did they work?

J Tiers
01-08-2009, 10:39 PM
Instead of a headstock riser, how about a headstock translator.

Den

Looks like we were typing at the same time.....

nheng
01-08-2009, 10:55 PM
JT, I've been pretty much brain dead at the end of the day lately and didn't notice your post. Should probably have posting license revoked :D

What I envisioned was something similar to but simpler than Logan's but the speed reduction aspect is definitely critical.

Oops, just noticed the posting times which was your original point :) I think it's time to sign off for the night ! Den

Evan
01-08-2009, 11:18 PM
The SB doesn't have enough power in back gear to take a decent cut on a 16 inch piece. Mine has what is probably the original motor since it is the instant reversing type. It's a 1/3 hp motor so there isn't any way it can drive anything much bigger. I already considered a riser but for practical purposes it could only be taken up a little, maybe to 10 inch. I may well do that.

John Stevenson
01-09-2009, 05:08 AM
So up the motor power.
Most Myford super 7#s nowadays are powered by 1 HP motors with VFD's
Only the very early dead basic ML7 had a wimpy 1/3 HP but they soon changed it.
There have been plenty of high rise conversions over the years, Radford covers one in his Lathe Attachments book and Myfords even made a high rise lathe.

From the lathes.co.uk website

http://www.lathes.co.uk/myford/img33.gif


1951 Myford ML7 "High-swing" lathe of about 6" centre height. A batch of these lathes were constructed for the brake and clutch lining firm of Ferodo Ltd. (of Chapel-en-le-Frith, Derbyshire), to equip their motor and motorcycle-racing service vans. In the days just before the introduction of discs, drum brakes had grown to enormous sizes and a lathe was required which, whilst needing to be of only relatively light construction, had to be able to turn large diameters. A full-sized lathe would not only have been unnecessary, but also just too unwieldy and heavy to transport.
Although suggestions have been made that the lathe was designed for turning brake drums it is more likely that the large faceplate carried jigs to hold brake shoes and clutch plates and so enable them to be turned true after being relined. Although the headstock was raised by using a simple distance piece, the tailstock base was a special and rather well-designed casting. The cross slide, its end bracket and the zeroing micrometer dial were of the "Super 7" type used on long-bed ML7s and the (Super 7) top slide sat on a neatly-cast hollow block that brought it out to a position where the cutting tool could be made to reach the outer area of the faceplate. The changewheel drive to the leadscrew was provided with a longer banjo arm and fabricated inner and outer covers were made to suit. Although tentative plans to market the lathe were apparently made, nothing further was heard of the idea.
At least one standard centre height lathe with a capacity of 5 feet between centres was also made - and last seen in the north of England in the late 1980s







http://www.lathes.co.uk/myford/img34.gif

Somewhere in all the papers and books I got off Glynn Jones, Myfords Design engineer is a far better 10 x 8 glossy of this lathe, I'll have to look it out and let Tony Griffiths at lathes.co.uk have a copy

darryl
01-09-2009, 05:08 AM
I slept on a gap bed once. Worst night of no sleep I ever got. :)

Evan
01-09-2009, 05:44 AM
I would hate to lose the instant reversing feature. Also, the flat belt drive would have to be changed for something better. That would mean changing the cone pulley in the headstock.

I am building another lathe not just for the swing. It will be nice to have a second lathe.

aboard_epsilon
01-09-2009, 08:09 AM
I've got 3/4 of hp on my south bend 9

Instant revercing ...whats that ? ...........mine only takes a couple of secs to stop before i can reverce it ...like how much of a hurry are you in !

all the best.mark

MickeyD
01-09-2009, 08:10 AM
Evan, I had a 10L Southbend with a flat belt and a 1.5HP motor and it would take decent cut before the motor would bog or the belt would slip. I always loved the old flat belt lathes - simple and quiet and the belt slippage was sort an oops filter. Much more forgiving than a gear head.

Evan
01-09-2009, 08:50 AM
Instant reversing motors can be "plugged" or switched to reverse while doing full speed. On mine it takes the motor about half a second to stop and start in the opposite direction. This is unusual in a single phase motor but makes it really handy for threading right up to a shoulder. In back gear it will take the lathe to a dead stop in a quarter turn or less of the chuck by just blipping the reverse. And no, it doesn't unwind the chuck.

J Tiers
01-09-2009, 08:51 AM
The SB doesn't have enough power in back gear to take a decent cut on a 16 inch piece. Mine has what is probably the original motor since it is the instant reversing type. It's a 1/3 hp motor so there isn't any way it can drive anything much bigger. I already considered a riser but for practical purposes it could only be taken up a little, maybe to 10 inch. I may well do that.

The point you missed is that the adapters, or sub-spindles, have ANOTHER back gear added.....

While your "power" as you say is the same either way, you have to look at it differently.

1) *****you need "power" to get deeper cuts and/or higher speed at any fixed diameter. Larger diameters at constant power mean slower speeds. The speed reduction needed to get slower speeds also runs the torque UP, so you get reasonably constant power. This obviously depends on getting your power through the belt system without slippage.

2) *****Power isn't what it is cracked up to be. I have a 1/3 HP motor on my 10", and I have never stalled it. I have slipped belts, but never stalled the motor. See point 4.

3) *****But you are unlikely to need high speeds at larger diameters in any case. You do a lot of aluminum work. Aluminum is typically a 300 SFM material or so. At least that is what the tables generally suggest as the lower end of the range. Most of us don't get to the top end of the tables except for finishing cuts. Aluminum is usually the commonly used material calling for the highest speed range.

At a 4" diameter part, that 300 SFM is going to be a tad under 300 RPM, if you can get an acceptable depth of cut at that speed.

At a 12" diameter, which you would need an adapter for, your max speed is going to be only 100 RPM, which is in the normal back-gear range.

For CRS etc, the 12" speed would be no more than 33 RPM, which may be lower than your back gears even go.

4)*****you can only get so much power through your 1" flat belt. In general, for most of the lathe speeds, unless you are a huge user of back gear, the most power you can get is about 0.25 HP, or a bit under 200W. Available belt tension is limited before slip, and so the SPEED is key. Keep it high for max power.

The lowest end speed of back gears is normally with the other belting already in the slowest speeds, meaning that the flat belt is used below optimum speed. You won't get max power through it unless you have unbelievable tensions, or the stickiest belt around. if you have an ADDED reduction, you can run the flat belt speed higher for any given work speed, allowing more power through it.

5) *****If you are still using a single-phase motor, get rid of it. 3 phase is only a few dollars away if you make a rotary converter from a surplus motor.

The combination of the very "pulsed" nature of single-phase power , AND the "slip-clutch" behavior of flat belts is deadly. The belt slips way early, on peak torque, and often requires shutting off power to stop slipping or replace the belt onto the pulleys..

Three-phase power is much smoother, and does not include the "torque peaks" inherent to single phase. Subjectively, the machine I have seems "twice as powerful" with three phase of the same motor rating. Flat belt slippage is both drastically reduced, AND I can recover from it by backing off the feed.... it isn't a 'break-loose" situation, it slips while still cutting. That allows recovery without shutting off power.

So

Given the above arguments, the sub-spindle with speed reduction makes a lot more sense than you think. Your suggestions about "lack of power" may not be as important as you think.

And, converting to three phase may allow you to use a larger motor effectively through the same flat belt.

Evan
01-09-2009, 09:01 AM
But you are unlikely to need high speeds at larger diameters in any case. You do a lot of aluminum work. Aluminum is typically a 300 SFM material or so. At least that is what the tables generally suggest as the lower end of the range. Most of us don't get to the top end of the tables except for finishing cuts. Aluminum is usually the commonly used material calling for the highest speed range.


300 sfpm is what I cut steel at using solid carbide. I am NOT putting a more powerful motor and a more positive drive on the SB. That would be a good way to break gears and get into other trouble. It isn't designed for that. It is a small sturdy lathe but anything more than what it has now would make it easy to overload the spindle bearings. I have stalled the motor on the SB.

kvom
01-09-2009, 09:06 AM
If he had modified the existing lathe, we wouldn't have these entertaining and interesting threads to read ;-)

I'm enjoying the build.

JCD
01-09-2009, 09:20 AM
As a general rule, in machine tool design is: The more mass the more rigidity. I don't know what you are planning on turning, but you may get some flexing in the bed with the design as shown.

Evan
01-09-2009, 09:39 AM
Mass and rigidity are not directly dependent on each other. I can build an extremely rigid structure that has very low mass. My telescope is an example of that. It uses pultruded graphite fiber shafts in a truss design that make a stucture with very minimal flex in all six axes. Mass is good for lowering resonant frequency which is a key method for reducing chatter tendency. Mass also helps to simply keep things in place. The stand will be a part of the lathe and will contribute a significant amout of strength to the design. This is true of many lathes including my South Bend. The South Bend is mounted on a large piece of channel iron and that in turn is mounted on a extremely strong double sided box panel with 3/4" plywood glued and screwed to a frame of 2x4s.

jackary
01-09-2009, 10:23 AM
Message deleted

Evan
01-09-2009, 10:41 AM
That's a beauty Alan. It looks to be extremely versatile and well thought out.

I'll be looking at some more of the videos later but right now I have a big block of steel in the band saw to tend.

Welcome to the forum and quite the entrance I must say. This lathe project is no comparison as it is what I would call a "scrap build".

S_J_H
01-09-2009, 11:08 AM
Alan,
That may be the most impressive shop built machine I have ever seen!

Any chance you will have plans available for it?

Steve

aboard_epsilon
01-09-2009, 11:08 AM
Hi Evan
I like your lathe design mock up, looks to be an interesting design.
I have recently built this machine, which you may be interested in.
Over the past few years I have been designing and building a variation
on the Metalmaster. It is made from solid cast iron blocks and
standard mild steel sections to avoid making castings. The essential
difference to the Metalmaster is that the bed remains stationary and
supported at each end and the head and tailstock can be raised or
lowered relative to the bed. A secondary vertical column is
incorporated in the integral tailstock to avoid an unsupported overarm
and tailstock. The machine uses stepper motors to drive each axis. A
separate stepper motor is dedicated to driving the headstock for indexing
the mandrel when required (Stepperhead)
A 430 watt 3 phase inverter controlled motor is mounted on the lower end of the raising column.
Using the polyvee pulleys and inverter give speed range of 15 to 3200 rpm.
The headstock can be moved up or down to change the centre height which can vary between
80 mm to a max of 220mm for large diameters and allow it to be also be used as a milling machine.
The axes can be operated either manually, power driven
by the stepper motors or CNC operated via the lap top computer. I
entered this machine in the Model Engineers Exhibition in 2008 at
Ascot UK where it was awarded a Gold Medal and The Bowyer-Lowe Trophy.
I have written an article which will be printed in the Model Engineers
Workshop soon. I have added a couple of photos under Stepperhead. I
have also added some dodgy videos on utube

http://www.youtube.com/watch?v=Yiug1F8XCME&feature=user
http://www.youtube.com/watch?v=yMxv1jU-R_A&feature=user
http://www.youtube.com/watch?v=FDNTeuojC78
http://www.youtube.com/watch?v=wNxgWhizX54
http://www.youtube.com/watch?v=DMmDCHkff0c&feature=user
http://uk.youtube.com/watch?v=sCsZN8Spbq8
http://www.flickr.com/photos/32647007@N02/sets/72157610446872607/

Regards
Alan

wow ...you just made every one here look like simpletons :D

all the best.markj

tony ennis
01-09-2009, 11:20 AM
Jackary... impressive. I can't make any single part of that machine!

jackary
01-09-2009, 11:37 AM
Alan,
That may be the most impressive shop built machine I have ever seen!

Any chance you will have plans available for it?

Steve

Steve,
I have been making some plans and instructions but it is a lot of work and I am only half finished. I was thinking of trying to make a book with descriptions and plans but wonder if there would be enough interest.
Regards
Alan

aboard_epsilon
01-09-2009, 11:42 AM
Steve,
I have been making some plans and instructions but it is a lot of work and I am only half finished. I was thinking of trying to make a book with descriptions and plans but wonder if there would be enough interest.
Regards
Alan

Make a book on that ..and it will be a hot seller .

sorry lots of questions

Is it made of stainless steel ?

How much did it cost to build ?

What machines were needed to build it ?

How long did it take you to build it ?

all the best.markj

GKman
01-09-2009, 11:47 AM
Evan,
You better incorporate all of the changes these guys are suggesting. You know what a dismal failure your mill design has been.;)

John Stevenson
01-09-2009, 02:30 PM
Alan,
First off welcome to the board.

I saw the links to your lathe from another site, can't remember the link though.
That truly is a work of design more than art. Art is touchy feely, that is impressive design.

There would be a market for plans if you did do some, not saying many would build it but many would buy the plans. that's the way it is. Old Cecil Mooore who used to own Myford once told me that if they charged a nominal sum for every leaflet and sales flyer printed they would have made more profit just from these than all the lathes they ever built.

Can you explain how the cross slide mechanism works as regards manual to CNC ?
I gather it has a worm and wheel to bring into play when in CNC mode but how does this disengage when in manual mode ?

Also if it is work and wheel is there any backlash problems when reversing the drive when doing say blended radii ?

.

jackary
01-09-2009, 03:09 PM
Make a book on that ..and it will be a hot seller .

sorry lots of questions

Is it made of stainless steel ?

How much did it cost to build ?

What machines were needed to build it ?

How long did it take you to build it ?

all the best.markj

Hi Markj
It is made of cast iron billets good stuff from College Engineering, polishes up well, the rest is mostly mild steel and aluminium, no exotics. It took about 2 years to build on a Colchester Chipmaster and a Senior M1 mill and my home made surface grinder. The hardest bit was doing the electronics a steep learning curve. It was not cheap materials, inverter, Stepper drives and motors etc add up to about £600 or so. Thanks for your generous comments.
Regards
Alan

noah katz
01-09-2009, 03:10 PM
"Mass is good for lowering resonant frequency which is a key method for reducing chatter tendency."

I thought chatter was from too low a resonant freq; has anyone been able to stop it by increasing speed?

John Stevenson
01-09-2009, 03:19 PM
It was not cheap materials, inverter, Stepper drives and motors etc add up to about £600 or so. Thanks for your generous comments.
Regards
Alan

That seems very reasonable to me, about the same price as a second hand Myford but not in the same class.

Now compare this to a Cestrian

http://www.chesteruk.net/store/cestrian_multi_function_machine.htm

Nearly two grand and no CNC.

.

jackary
01-09-2009, 03:24 PM
Message deleted

Evan
01-09-2009, 04:05 PM
The machine uses stepper motors to drive each axis. A
separate stepper motor is dedicated to driving the headstock for indexing
the mandrel when required (Stepperhead)


That is similar in concept to the 4th axis drive on my mill.

http://metalshopborealis.ca/pics4/twist1.jpg

It has both a stepper for indexing and a high speed servo for lathe work

You can see it in action here:

http://metalshopborealis.ca/misc/4_axis_twist_lo.wmv

topct
01-09-2009, 04:21 PM
"A non-rotating feedscrew fixed to the side of the cross slide meshes with a centrally positioned worm wheel. The operating handwheel rotates a worm, which meshes on the opposite side of this wormwheel. Handwheel rotation rotates the worm which rotates the wormwheel to move the cross slide. The handwheel shaft and worm are located 10 degrees from directly opposite the cross slide feedscrew, so that the axes of the feedscrew and worm converge.

The wormwheel pivot position is adjustable between these converging axes to position the wormwheel for minimum backlash with the worm and feedscrew. The wormwheel pivot shaft is clamped to the saddle by two socket head screws accessible from underneath the saddle. When these screws are slackened the wormwheel is free to move between the handwheel worm and the feedscrew on the cross slide. Rotating the handwheel in a clockwise direction will cause the wormwheel to move away from the narrowing axes convergence, increasing the backlash. Whilst rotating the handwheel in an anti-clockwise direction causes the wormwheel to wedge between the narrowing axes, reducing the backlash. By manipulation the wormwheel in this manner the backlash can be set to a desirable minimum, then the pivot screws are then locked."

Cool.........

Evan
01-09-2009, 04:21 PM
I thought chatter was from too low a resonant freq; has anyone been able to stop it by increasing speed?


Try this sometime when you are boring and the bar is chattering. Clamp a pair of locking pliers to the bar next to the tool holder. Alternately I use a hefty brick of lead and just place it on the rear skirt of the cross slide. The lower the resonant frequency the less chance of exciting it in the first place. A given impulse can easily excite a resonant fundamental that is a higher harmonic of the exciting frequency. If the resonance fundamental is lower than the exciting impulse it is much less likely to be excited even if it is a submultiple.

As to your question, certainly. Raising the speed can be just as effective as lowering it. The problem that may occur is that once there are chatter marks in the work raising the speed may increase the amplitude of the exciting impulse as the tool encounters the marks.

lazlo
01-09-2009, 04:33 PM
Thank you for your encouraging comments. This is how the cross slide works. A conventional lathe cross slide is usually operated via a feedscrew moving the nut attached to the cross slide. The extent of travel is limited by the necessary location of the handwheel. The method used by the Stepperhead is unconventional but offers some advantages. The free space under the tailstock allows a full width saddle, rather than the conventional wings each side of the tailstock and permits this design.

Holy Cow -- that's simply gorgeous Alan!!

A lot of folks say that 5Bears CNC mill is the most sophisticated home-built machine tool every made:

http://www.5bears.com/cnc.htm
http://www.5bears.com/cncm1/p24_07.jpg

You use less exotic components, but I thinking your "Stepperhead" gives Swede a run for his money! :) The fit and finish is superb!

Did anyone see the CNC toolpost grinder cutting rifling? :eek:

http://www.youtube.com/v/5cKuOvh4uLI&hl=en&fs=1

lazlo
01-09-2009, 04:38 PM
Here Allan is doing gearcutting with an involute cutter:

http://www.youtube.com/v/wNxgWhizX54&hl=en&fs=1

John Stevenson
01-09-2009, 04:40 PM
Here Allan is doing gearcutting with an involute cutter:



Nope sorry you need to edit your post that is gear cutting index, cut, index etc.

.

lazlo
01-09-2009, 04:42 PM
Nope sorry you need to edit your post that is gear cutting index, cut, index etc.

He's using a single-point involute cutter, and indexing the lathe mandrel and driving the milling head by CNC.

What did I miss John?

Alistair Hosie
01-09-2009, 04:51 PM
what's that filthy muck you've got in the tub next to the sanding discs???? yuk yuk.:DAlistair

Evan
01-09-2009, 04:56 PM
Ferric chloride for etching stainless steel.

S_J_H
01-09-2009, 05:01 PM
Did anyone see the CNC toolpost grinder cutting rifling? :eek:

Well that settles it, I'll be adding a stepper drive for the spindle on my HBM/lathe thingamabob build, as well as live tooling for the table and a separate vertical milling column. After seeing Alan's incredible machine, it has made rethink my entire build.
My machine won't be "pretty" though,, well maybe pretty f-ugly :D

Steve

Rigger
01-09-2009, 05:08 PM
That machine of Alan's is better than a plank of wood any day.

topct
01-09-2009, 05:21 PM
And it only cost him about $1000 US.

John Stevenson
01-09-2009, 06:10 PM
Alan,
Thank you for the description it was easy to understand given your account.
That layout of the cross slide screw is very novel as is the method of adjustment.
Thank you again for shedding a fresh approach to an old subject, which also goes to show you learn something new every day.

Alan, what part of the UK are you from ?

.

motorworks
01-09-2009, 06:17 PM
Alan
Your tail stock setup got me thinking...
nice ;]

eddie

S_J_H
01-09-2009, 07:44 PM
And it only cost him about $1000 US.
I think that was for the electronics only.;)

Steve

lazlo
01-09-2009, 08:29 PM
Did you notice the mahogany control tower? That's class! :D


Alan
Your tail stock setup got me thinking...

The tailstock looks inspired by the Cazeneuve (French toolroom lathe) tailstock.

wierdscience
01-09-2009, 08:53 PM
Very nice design Alan,the cross slide arrangement is brilliant!

J Tiers
01-09-2009, 10:01 PM
300 sfpm is what I cut steel at using solid carbide. I am NOT putting a more powerful motor and a more positive drive on the SB. That would be a good way to break gears and get into other trouble. It isn't designed for that. It is a small sturdy lathe but anything more than what it has now would make it easy to overload the spindle bearings. I have stalled the motor on the SB.

if you are running 300 SFM with steel with any sort of a depth of cut on your S-B 9" machine, then you need to get a different lathe, OR you need more realistic goals, OR you are fibbing a bit.

You are suggesting that you are running from 600 RPM (assuming around a 2" workpiece) to 1200 RPM (a bit under a 1" workpiece) ,using carbide, and some reasonable depth of cut like 40 thou with steel.

If your 9" S-B will pull any sort of decent cut with 0.040 DOC at 1200 RPM in steel using carbide, then it is certainly NOT the case that you need any more power than you have..... I sure wouldn't put a bigger motor on it, you are getting everything the machine has to give you, plus some extra.

You could very easily use the "booster spindle" and you would have no problems.

The 1860 style combo wood and steel lathe you are proposing may not be the machine you need either, it will have the swing, but may not have the mass and rigidity to do what you want, or to "live up to" its swing.

I would expect the "booster spindle" to outperform it. And you will have spent considerably more effort on it than taking what you have and adapting it as a "booster".

You must suit yourself, however. If you like it, that would be fine with us.

J Tiers
01-09-2009, 10:12 PM
"Mass is good for lowering resonant frequency which is a key method for reducing chatter tendency."

I thought chatter was from too low a resonant freq; has anyone been able to stop it by increasing speed?

Chatter is from a resonance. The 'cut and release chip" cycle occurs at a frequency that the system resonates at, so you get a series of marks on the work. It is due to the cutter nodding into the work from cutting force, taking a heavier cut, which "winds it up" somewhat, reaching a point where the spring force overcomes the strength of the work so that the cutter jumps up, releasing the chip and starting the cycle over again. the work gets "scallops" on it.

The system has to resonate at a frequency which the cutter system can produce, but that's about it.

Another form is due to torque ripple in a single phase motor, which can mark the work and produce similar sounds.

The difference is that a regular resonance type chatter may occur at different pitches (frequencies), depending on conditions. You can usually speed up or slow down and get rid of it.

The motor torque chatter tends to always be the same pitch, and virtually nothing fixes it.

Evan
01-10-2009, 01:02 AM
if you are running 300 SFM with steel with any sort of a depth of cut on your S-B 9" machine, then you need to get a different lathe, OR you need more realistic goals, OR you are fibbing a bit.


No, not fibbing. I am usually running my lathe these days at the highest speed for most cuts unless I am really taking off as much material as possible. The highest speed is about 830 rpm since I have changed the ratios from standard. I haven't turned any aluminum for a while now, mostly it is steel. I use non-standard tooling that I grind myself from large pieces of solid carbide. The last piece of steel that I was turning yesterday was a 4.5 inch diameter piece of pipe. I was removing scale and rust and turning it at about 200 rpm. That's 235 sfpm. I wasn't taking .040, it won't do that. Probably more like .020 doc. The chips come off smoking and turn blue.

I am not interested in making any sort of permanent changes to the SB. The only one that I have made was to add a proper dial to the tailstock. The rest of the items such as the power drives are bolt on accessories.


The 1860 style combo wood and steel lathe you are proposing may not be the machine you need either, it will have the swing, but may not have the mass and rigidity to do what you want, or to "live up to" its swing.


Wait and see.

jackary
01-10-2009, 05:58 AM
Alan, what part of the UK are you from

Essex Billericay CM11 Pop in and see it if your ever near there
Alan

John Stevenson
01-10-2009, 06:07 AM
Thank you Allen,

It's not often I get that way mainly travelling more East and North but I will bear it in mind. Essex to me means using the A14 and I hate that road, it's 2 hours of going nowhere :(

.

jackary
01-10-2009, 06:58 AM
John
The A12 is even worse
Alan

John Stevenson
01-10-2009, 07:18 AM
I think we should end this conversation on this post as we are being accused of being related, know each other and by 11 O'clock probably in an incestuous relationship with one another.

It's seems the self appointed Alpha male on this list with 22,453 posts to his name is getting a bit touchy.
perhaps he's read the label wrong on his medication and got the decial point in the wrong place.
after all when you are used to working to 0.0000000012345 it's easy to do.

J Tiers
01-10-2009, 12:16 PM
I am not interested in making any sort of permanent changes to the SB. The only one that I have made was to add a proper dial to the tailstock. The rest of the items such as the power drives are bolt on accessories.



I hope you DO realize that the proposed "sub-spindle" setups are ALWAYS bolt-on accessories.... they are MOST DEFINITELY NOT "permanent".

speedsport
01-10-2009, 01:04 PM
Hi Evan
I like your lathe design mock up, looks to be an interesting design.
I have recently built this machine, which you may be interested in.
Over the past few years I have been designing and building a variation
on the Metalmaster. It is made from solid cast iron blocks and
standard mild steel sections to avoid making castings. The essential
difference to the Metalmaster is that the bed remains stationary and
supported at each end and the head and tailstock can be raised or
lowered relative to the bed. A secondary vertical column is
incorporated in the integral tailstock to avoid an unsupported overarm
and tailstock. The machine uses stepper motors to drive each axis. A
separate stepper motor is dedicated to driving the headstock for indexing
the mandrel when required (Stepperhead)
A 430 watt 3 phase inverter controlled motor is mounted on the lower end of the raising column.
Using the polyvee pulleys and inverter give speed range of 15 to 3200 rpm.
The headstock can be moved up or down to change the centre height which can vary between
80 mm to a max of 220mm for large diameters and allow it to be also be used as a milling machine.
The axes can be operated either manually, power driven
by the stepper motors or CNC operated via the lap top computer. I
entered this machine in the Model Engineers Exhibition in 2008 at
Ascot UK where it was awarded a Gold Medal and The Bowyer-Lowe Trophy.
I have written an article which will be printed in the Model Engineers
Workshop soon. I have added a couple of photos under Stepperhead. I
have also added some dodgy videos on utube

http://www.youtube.com/watch?v=Yiug1F8XCME&feature=user
http://www.youtube.com/watch?v=yMxv1jU-R_A&feature=user
http://www.youtube.com/watch?v=FDNTeuojC78
http://www.youtube.com/watch?v=wNxgWhizX54
http://www.youtube.com/watch?v=DMmDCHkff0c&feature=user
http://uk.youtube.com/watch?v=sCsZN8Spbq8
http://www.flickr.com/photos/32647007@N02/sets/72157610446872607/

Regards
Alan

Very nice machine. Your far too talented to be hanging around here in these poverty scrap junk yard build threads!!

Alistair Hosie
01-10-2009, 04:25 PM
Very well done my friend you are a true machinist engineer as well as designer good luck for the future and a hearty welcome .Alistair

davidh
01-10-2009, 05:35 PM
Alan, what part of the UK are you from

Essex Billericay CM11 1NS Pop in and see it if your ever near there
Alan

hyjack hyjack. google earth the address.. . . . . interesting. lot of buildings on a smalll road, encompassed by country openness. looks like a great place to live. . . . .

aboard_epsilon
01-10-2009, 05:43 PM
They are million pound houses .


john would have to use the side entrance ..and wait for the butler to answrer the door. :D
all the best.markj

speedy
01-10-2009, 06:20 PM
Essex Billericay CM11 1NS Pop in and see it if your ever near there Alan

And he aint a blimmin thicky either!

Impressive lathe/workmanship Alan.
That lathe deserves its own thread though...........


They are million pound houses .
Pre or current recession valuation??:)

Evan
01-10-2009, 07:13 PM
One must ask why Alan chose to post about his CNC machine in this thread. It is about as far removed from what I am building as you can get. Further he certainly went to a lot of trouble to make his grand entrance here. It probably took all of 10 seconds to copy and paste his post from one of many with exactly the same wording the he has previously posted on other forums. On those he managed to figure out how to start his own thread.

http://www.rittercnc.com/modelengineering/Stepperhead-7463-.htm

http://www.modelgeeks.com/Uwe/Forum.aspx/uk-model/5235/Stepperhead

It was clearly nothing but a hijack bomb. Alan is familiar with forum etiquette, if for no other reason that he has been signed up here for two years.

A.K. Boomer
01-10-2009, 07:24 PM
Now I got a beer in me ---- Evan, you need to deal with it, I know for a fact that now your being unfair, Iv seen you either "upstage" or try to (with pics) just about everyone here on a "variation of the theme" Get over it --- there's plenty of talent to go around --- quit being so freakin petty

John Stevenson
01-10-2009, 07:40 PM
One must ask why Alan chose to post about his CNC machine in this thread. It is about as far removed from what I am building as you can get. Further he certainly went to a lot of trouble to make his grand entrance here. It probably took all of 10 seconds to copy and paste his post from one of many with exactly the same wording the he has previously posted on other forums. On those he managed to figure out how to start his own thread.

http://www.rittercnc.com/modelengineering/Stepperhead-7463-.htm

http://www.modelgeeks.com/Uwe/Forum.aspx/uk-model/5235/Stepperhead

It was clearly nothing but a hijack bomb. Alan is familiar with forum etiquette, if for no other reason that he has been signed up here for two years.
Even,
These are all the same threads that you posted before, they are other people hosting the URME group.
Read the threads and look at the posters, they are all the same.

I even know one guy, Tony Jeffree, met him, been to his house and bought a Divisionmaster unit off him. Does that count against me ?


He hasn't posted these separately the various sites have hijacked the URME list.

So you have NEVER posted what you have done on someone elses thread ?
Get real, get a life and move on, contrary to what you may think this isn't your sole sandpit.
Reading the replies printed today and the PM's it seems that you don't have much support, what's the next move drop me and pick on Alan because if you are expecting me to roll over because of this you are very much mistaken. I got made redundant from my last job for calling the Engineering Manager a bullsh1ting bastard in a production meeting [ no joke - true story ] and it was the best thing to happen to me, job loss or not.

S_J_H
01-10-2009, 07:47 PM
Perhaps he just wanted to show off his machine.I sure the heck would if I had built it! He found a thread here on a scratch built machine and decided hey, lets show these guys what I can do!:)
I would not take it personally Evan. I mean, hell I even got sort of depressed after seeing it compared to what I am currently building. But on the other hand, mine may not be so beautiful but I'll bet it takes a deeper cut and is possibly more accurate and rigid. After all I am using a top of the line Gilman slide, meehanite base, ground ways, beautiful scraped surfaces with oil grooves and .0005" accuracy over 36" travel. 200lbs right there in the base alone
Alans machine is to me a form of machine art. It's gorgeous!!! It's not relevant to what you are building. But it's not so unusual that it was brought into this thread.
Let it slide and move on.

Steve

aboard_epsilon
01-10-2009, 08:18 PM
Googled and found Allan

He had posted his stuff in cnc zone ..a few months back .....

Amazingly ...He only got a few replies .....

I can see how that could happen ..as there are a gazillion forums at that place ..bet it made him feel a bit small if you ask me.

I don't think he posted to upset Evan .

I think Allan just responding to give some of his ideas away ..........and a form of encouragement to Evan, to think a bit differently...
and to get acknowledgement from people that he's done a superb job of it....which he never really got at the cnczone..without shouting it out in a separate post here ............which he was probably shy of doing.

all the best.markj

motorworks
01-10-2009, 11:05 PM
Alan tell me more about your build and how you came about that tail stock set up!

Is there any wood or glue use to make it?

jackary
01-11-2009, 06:33 AM
One must ask why Alan chose to post about his CNC machine in this thread. It is about as far removed from what I am building as you can get. Further he certainly went to a lot of trouble to make his grand entrance here. It probably took all of 10 seconds to copy and paste his post from one of many with exactly the same wording the he has previously posted on other forums. On those he managed to figure out how to start his own thread.

http://www.rittercnc.com/modelengineering/Stepperhead-7463-.htm

http://www.modelgeeks.com/Uwe/Forum.aspx/uk-model/5235/Stepperhead

It was clearly nothing but a hijack bomb. Alan is familiar with forum etiquette, if for no other reason that he has been signed up here for two years.

Evan,
I apologize it was not my intention to hijack your thread, I was interested in what you are making and was trying to share ideas. I realize now that I should start my own thread and you will be welcome to contribute. So I will stop any more feedback on your thread and have deleted what I can so as to start over again on a new one.
Regards
Alan

Doc Nickel
01-11-2009, 07:27 AM
Alan, you have to understand that Evan is a bit of a curmudgeon. He has fine skill and plenty of book-learning, but a rather poor "bedside manner", and he absolutely, positively, cannot tolerate criticism in any form.

This is not the first "blowup" involving him and John (or him and me, or him and any one of half a dozen other posters) and it surely won't be the last.

Don't take it personally. Evan treats everyone that way, unless they're openly fawning over his latest creation or expounding the brilliance of his latest posting. :D

Doc.

John Stevenson
01-11-2009, 07:35 AM
Doc, not to nit pick but you have spelt 'curmudgeon' incorrectly in your last post.

The correct spelling is 'bullshïtter'

.

Doc Nickel
01-11-2009, 07:56 AM
Bullsh*tting is a symptom. Being a curmudgeon is the cause. :D

Doc.

John Stevenson
01-11-2009, 08:03 AM
Thank you for the explanation, much appreciated. So it's not wholly down to the medication? or lack off ? :D


.

Evan
01-11-2009, 08:10 AM
Get stuffed John.

John Stevenson
01-11-2009, 08:12 AM
Get stuffed John.

Thank you for your permission.
.

aboard_epsilon
01-11-2009, 08:19 AM
while we are so off topic now

may as well post a question that may get deleted if i did it elsewhere

can anyone tell me why the Israeli's always have a north American person as their spokes person ........i don't think Ive seen a true Israeli yet in all broadcasts .

all the best.markj

Doc Nickel
01-11-2009, 08:20 AM
Thank you for the explanation, much appreciated. So it's not wholly down to the medication? or lack off ? :D

-Truthfully, in all seriousness, I'd expect a fair amount of it is due to isolation.

He's told us at length how sparsely populated the area is, how far it is to town, how rarely he travels there, and so on. He's married, but we hear little or nothing about his wife- we've heard more about his dog, point in fact.

His internet presence is, therefore, a significant percentage of his daily, person-to-person interaction.

But unlike having a single, good friend over for a beer and a chat, posting here is like trying to have a conversation in the same room as fifty other guys also trying to have forty other conversations, so things get sidetracked, and he ends up having to talk to or argue with people he didn't want to talk to in the first place, about things unrelated to the original topic.

Worse, the more one tries to force a topic in a certain direction, the more that topic drifts, which just adds to the frustration in that sort of situation. Note the rather telling bit from a recent post, saying he'd like to start his own BBS, so that he can control (IE, lock, exclude and delete) who posts and what- just as Adrian "3 Phase Lightbulb" did, and for curiously similar reasons, a few years ago.

Add to that the aforementioned absolute intolerance to criticism, and you have a curmudgeon. :D

Doc.

Evan
01-11-2009, 08:28 AM
Alan, you have to understand that Evan is a bit of a curmudgeon. He has fine skill and plenty of book-learning, but a rather poor "bedside manner", and he absolutely, positively, cannot tolerate criticism in any form.



Thank you. I will explain a bit. I am indeed sensitive about matters related to my machining skills but it isn't because of an inflated ego. To the contrary it is because I have lost the ability to do most of the things that I used to enjoy because of my medical condition. I can no longer take long wilderness canoe trips, pedal a bicycle for more than a minute or two, run more than a 100 feet even though I once ran the mile in full combat gear and boots in just over six minutes. Because of my sleep disorder I can't even drive for more than about 30 minutes without the very likely consequence of falling asleep at the wheel. I tend to fall asleep in any situation that I find boring and driving is number one on that list.

About the only thing I have left to me that I do well is machining and related activities. Attack that and you attack all I have that is worth doing.

John Stevenson
01-11-2009, 08:43 AM
About the only thing I have left to me that I do well is machining and related activities. Attack that and you attack all I have that is worth doing.

Quick pass my violin.............

OK points above accepted but why seeing as we are getting down to the nitty gritty do you have to bullshït so much ?

Why is everything precision?
Why does everything have to be THE BEST.?
Why does everything have to be to microns?
Why have you got the ONLY plank of unobtainium wood ?

Everyone else is happy to drill 100 holes on a job, you are / were able to drill 20,000 [ from your post] holes per hour for pop rivits.

Why do we not believe all this bullshït ??

Your issue is with me but in actual fact it's not, I'm just a convenient linch pin, read the replies to your whining post.

Just as you are sensitive about matters relating to your machining skills I'm hyper sensitive about bullshït

This was caused by me having to work with a grade A bullshïtter for 4 years non stop. Everything this guy did was better than anything anyone had ever done.
He was born in 1948, same year as me but had somehow managed to serve in all 3 armed forces in WWII and the Falklands.

I could go on but my blood pressure won't stand it, what is even worse that bullshïtting is the fact that they EXPECT you to be as gullible as them and BELIEVE it.

That's the worse part, expecting you to come down to their level.

End of rant.

.

MCS
01-11-2009, 08:44 AM
About the only thing I have left to me that I do well is machining and related activities. Attack that and you attack all I have that is worth doing.

Which puts you in a very vulnerable position.

Once I was paid for metalworking, I also designed title-winning motorcycles.

I know now that everybody who passed a shop where they sell lathes has a far more superior knowledge about the subject than I have, a knowledge they increase every day by copy and paste from the internet.

It makes me that humble so that all my projects are strictly in-house. It satisfies me, the more so because most advise can be construed as "how not to do it".

I also know now that "bearing" is a triggerword on the internet.

Your Old Dog
01-11-2009, 08:47 AM
I understand where Evan is coming from. I'm in a similar situation with health and locale. I have two broken ankles that prevent me from doing all that I wanted to do during retirement. About the best I can do is a few hours in the house and a few hours in the shop goofing around. I have a TV in the shop so I can watch TV out there instead of in the house where I seem to be all the time. I am embarrassed to tell you how often I check this site every day. It's a large part of my (hang on for this one) "social intercourse".

This board is a larger part of my life then it really should be but that's the way it is. I count damn near everyone here as a friend and, as I have a poor memory these days, even the one's who have taken a rare shot at me :D

I was raised by a father who couldn't find the instructions for me and thought he'd make me better by criticizing me me and so I don't take criticism well either. But I guess that's my problem and not yours. I just offer it as an explanation.

Doc Nickel
01-11-2009, 08:48 AM
About the only thing I have left to me that I do well is machining and related activities. Attack that and you attack all I have that is worth doing.

[Bolding mine]

-And that is precisely your problem. You view even the slightest criticism, or even just an opinion on an alternate methodology, as an "attack". An 'attack' on your skill, an 'attack' on your intelligence, an 'attack' on your process, whatever.

And until you understand that different people will offer different opinions and different viewpoints, and that, especially here, they are rarely, if ever, offered as an "attack", then you will remain a curmudgeon.

Moreover, if you treat those alternate viewpoints as "attacks", then other curmudgeons will respond by counter-attacking. I mentioned earlier "blowups"- you and I, you and John, you and JTiers, ad infinitum.

What's the common denominator in those?

Doc.

A.K. Boomer
01-11-2009, 09:08 AM
I think thats about enough you guys.

J Tiers
01-11-2009, 10:08 AM
[Bolding mine]

then other curmudgeons will respond by counter-attacking. I mentioned earlier "blowups"- you and I, you and John, you and JTiers, ad infinitum.

What's the common denominator in those?

Doc.

hey, now, where's lazlo in that list?

besides, I think you have it all wrong.... it is nothing to do with being (or not being ) a 'curmudgeon".

merriam-webster definition (hey at least its better than Fox news)

1) Miser

2) crusty, ill-tempered, and usually old, man

Nor is it truly involved with what Evan alleges concerning machining.... although I'll allow that might be part of it, why not?

Nope, it mostly is related to a person's tolerance for seeing/hearing another person "be wrong".

Some folks can do that and simply think to themselves "that's silly" and move on.

Others feel the need to convince the other person of what is "right".

That might be due to preferring not to see misinformation distributed unchallenged, which is at least useful, if generally unwelcome. Or it may be just because their pet peeve is "wrongness" and they have a compulsion to correct it.

There is no problem at that point.

The issue arises when the party of the first part (the one who was "wrong"), refuses, rightly or wrongly, to admit it. And the party of the second part (the accuser) likewise refuses to admit they themselves are actually wrong (again rightly or wrongly).

Mind, I am not assigning names to these parties of first and second part......

Usually the "wrong" position is maintained in the face of very good evidence to the contrary, which evidence is generally dismissed as irrelevant or BS, or is simply ignored. Naturally, the dissing of good evidence inflames the one who is actually correct, and it goes on.

Added interest occurs when one or the other party cherry-picks the points of the other, deliberately or inadvertently mis-interpreting them, and then attacks the points per the misinterpretation. This is very common, when one party 'skims" through what was written and misses the point.

Evan
01-11-2009, 10:21 AM
This is very common, when one party 'skims" through what was written and misses the point.

You mean like where I said I was going to put a belt drive "back gear" on this lathe?


What's the common denominator in those?



Quite often it's you. You are the one person on this board that has openly admitted that you will argue a point merely for the sake of argument and no other reason.

J Tiers
01-11-2009, 10:49 AM
You mean like where I said I was going to put a belt drive "back gear" on this lathe?



Quite often it's you. You are the one person on this board that has openly admitted that you will argue a point merely for the sake of argument and no other reason.

Sigh............ No, I am NOT going to get into it yet again....

Please re-read and note that I specifically declared I was NOT pointing fingers at ANYONE as the party of whichever point.

"ANYONE" includes Evan Williams, in case you were wondering about that.

And I don't think you got the point of the other matter either. I won't argue just to argue, or make up an argument. I have a tolerance for "argument", an enjoyment of a good argument, always assuming there is a basis for both positions, even if one is wrong..... I am not a general-purpose Sophist, nor do I enjoy arguing against the "I know you are, but what am I" style of debate (if you can call it that).

Many people consider that after one point & counter-point, that then the discussion has to stop because both people have made their positions clear, and further discussion is "an argument". They must have grown up in a pan-throwing, wife-beating house, because they equate "an argument" with name-calling and violence. I do not agree with that "politically correct" concept.

And AGAIN I am not suggesting anything with respect to Evan Williams, aside from what is inevitable in replying to a specific post.

Bye-bye, now.

Evan
01-11-2009, 10:59 AM
Did you not notice the quote? I make the asssumption that you know what you said. Doc said that, not you. You are responding to my reply to Doc.

Evan
01-11-2009, 11:23 AM
OK points above accepted but why seeing as we are getting down to the nitty gritty do you have to bullshït so much ?

Why is everything precision?
Why does everything have to be THE BEST.?
Why does everything have to be to microns?
Why have you got the ONLY plank of unobtainium wood ?

Everyone else is happy to drill 100 holes on a job, you are / were able to drill 20,000 [ from your post] holes per hour for pop rivits.

Why do we not believe all this bullshït ??

Your issue is with me but in actual fact it's not, I'm just a convenient linch pin, read the replies to your whining post.

Just as you are sensitive about matters relating to your machining skills I'm hyper sensitive about bullshït

This was caused by me having to work with a grade A bullshïtter for 4 years non stop. Everything this guy did was better than anything anyone had ever done.
He was born in 1948, same year as me but had somehow managed to serve in all 3 armed forces in WWII and the Falklands.

I could go on but my blood pressure won't stand it, what is even worse that bullshïtting is the fact that they EXPECT you to be as gullible as them and BELIEVE it.

That's the worse part, expecting you to come down to their level.



You do machining for a living and from what I can tell you do it very well. I do machining strictly as a hobby. I am a perfectionist. I do things in that regard that you don't and I am quite sure you don't understand why I do. I do not bullsh*t about what I do. I hold myself to that standard I set, not anybody else.

Everything that I do that requires precision often requires extreme precision. For example, the tracking accuracy on my telescope drive must be accurate to within less than one arc second per hour. That isn't my standard, it's what it must be to take good photos. You don't do what I do and don't have to deal with those matters. I do. Get used to it.

About the only thing we have in common is the total lack of a floor.

Bruce Griffing
01-11-2009, 11:28 AM
Evan-
I have a slightly different point of view. I appreciate your build posts a lot. I think you have been able to accomplish a great deal with a very small collection of resources. Good for you!! Further, most of your areas of interest are self taught. Again - good for you!! Finally - you are very creative. You pursue interesting things and find interesting stuff - you exploration of "the sound of light" being an example. All to your credit.
That said, I do think it is true that at times, you mistake many innocent comments as attacks. Please don't. You are a good contributor to the board. We appreciate your contributions. If one of your threads starts a long conversation - so much the better. Just let it go!!

J Tiers
01-11-2009, 11:35 AM
Did you not notice the quote? I make the asssumption that you know what you said. Doc said that, not you. You are responding to my reply to Doc.

Well, since "I" certainly have openly admitted that I like to "argue" (did someone else say that also? You stated it was a single unique individual), and the other point was applicable to a specific point I recently made to you, I did suppose you were replying to me.....regardless of the SECOND quote.....

The first quote was directly from my post....... The second from Doc. And you posted under mine.

Your disclaimer is BS, or else you have made a mis-quote.

dp
01-11-2009, 12:01 PM
What's the common denominator in those?

Doc.

Argumentative people who are intolerant of perfectionists? What'd I win?

John Stevenson
01-11-2009, 01:24 PM
Don't know but don't forget folks to copy and paste this thread tonight as when George come in fresh as a daisy in the morning it will be gone.

in 10 years time this will be a collectors item :D

Together with this classic.

http://www.stevenson-engineers.co.uk/files/evans%20saw2.jpg

.

Bruce Griffing
01-11-2009, 01:40 PM
John-
Being a vassal to the queen and guardian of Sudspumpwater, don't you think baiting Evan is beneath your station?

Rustybolt
01-11-2009, 02:29 PM
while we are so off topic now

may as well post a question that may get deleted if i did it elsewhere

can anyone tell me why the Israeli's always have a north American person as their spokes person ........i don't think Ive seen a true Israeli yet in all broadcasts .

all the best.markj


Israelis immigrants come from all over so it isn't inconcievable for a spokesperson to N. American.

noah katz
01-11-2009, 03:55 PM
Evan,

“Clamp a pair of locking pliers to the bar next to the tool holder. Alternately I use a hefty brick of lead and just place it on the rear skirt of the cross slide.”

I presume you mean that this was effective from the additional mass/lower resonant freq, but you’ve also added stiffness and damping.

“The lower the resonant frequency the less chance of exciting it in the first place. A given impulse can easily excite a resonant fundamental that is a higher harmonic of the exciting frequency. If the resonance fundamental is lower than the exciting impulse it is much less likely to be excited even if it is a submultiple.”

You can make the same argument about exciting a resonance with integral multiples or submultiples of the resonant freq; in fact it’s generally accepted in mechanical engineering and control systems (think CNC) that once you approach and/or exceed resonance, you’re toast, and that the surest way to avoid resonance issues is to stay well below resonant freq.

Except when you want isolation, like in vehicle suspensions, where the goal is that bump freq be higher than suspension freq, but in machining that’s the last thing we want is to isolate the cutter from its mechanical commands.

I’m trying to think of an example where only the resonant freq is different, but the mass/stiffness are pretty much always intertwined.

Let’s see… if you had an aluminum boring bar that was 1.5X the diameter of a carbide boring bar, they would have the same bending stiffness, but the aluminum bar would have a 30% higher resonant freq.

Not sure if that’s enough difference to give a clearcut result.

“I once ran the mile in full combat gear and boots in just over six minutes.”

Most impressive. That’s about the best I’ve done unemcumbered.

dan s
01-11-2009, 04:13 PM
If a few of you have a problem with what Even posts, why the F do you read them then? Last time I checked no one what holding a gun to your head forcing you to read his posts and respond.

Peter N
01-11-2009, 04:24 PM
If a few of you have a problem with what Even posts, why the F do you read them then? Last time I checked no one what holding a gun to your head forcing you to read his posts and respond.

Ah, but that's just human nature Dan.
Plus, if you know better then the OP (any OP, not just Evan), and can correct a misconception or inaccuracy, then as public-spirited forum brothers surely we're obliged to do so?
However, the manner and tone can also vary due to that same human nature, but that's just people :D

Peter

John Stevenson
01-11-2009, 04:28 PM
John-
Being a vassal to the queen and guardian of Sudspumpwater, don't you think baiting Evan is beneath your station?

One has to rise to any occasion...........

.

SVS
01-11-2009, 04:37 PM
N. American spokespersons make sense-Our national greatness is inextricably linked to our support of Israel, and their survival depends on our support.

To get back on topic-I find the multiple repetitive suggestions for riser blocks and sub headstocks a lot more annoying than anything else about this thread. Does anyone really think that Evan had not considered, could not execute, or just over looked riser blocks. If that is what he wanted it would have already been done-He wants to build a lathe, wish him well, or sit back and wait for it to fail but telling him to close the gate after the chickens are out proves only an astounding grasp of the obvious.

I lurk often, post rarely, and I swear the hissy fits around here happen like clockwork, the hand wringing is predictable to the last detail, it's always deja-vu all over again, the only change is which actor gets which lines.

That was the boringly predictable "caring yet stern fatherly rebuke" right there. It's one step nicer than my all time favorite movie line-"You aggravatun suns a bitches, Ya'll are like playing cards with my brothers kids."

dan s
01-11-2009, 04:45 PM
Plus, if you know better then the OP (any OP, not just Evan), and can correct a misconception or inaccuracy, then as public-spirited forum brothers surely we're obliged to do so?

They are doing a piss poor job then, that or they are being very selective of who they correct. For example about half (exaggerating) the information on this forum about insert tooling is wrong.

Peter N
01-11-2009, 04:54 PM
For example about half (exaggerating) the information on this forum about insert tooling is wrong.

Then start a new post titled "Everything You Need To Know About Insert Tooling" and point out how it should be done. If it's a good post then I'm sure you'll get the plaudits, but if not then you may have to expect the brickbats too. :D
You may also have to accept that different people find that insert tooling works better in conditions that aren't strictly textbook, and of course show that you're bothered when they disagree with what you post.

Peter

speedy
01-11-2009, 04:59 PM
Thank you. I will explain a bit. I am indeed sensitive about matters related to my machining skills but it isn't because of an inflated ego. To the contrary it is because I have lost the ability to do most of the things that I used to enjoy because of my medical condition. I can no longer take long wilderness canoe trips, pedal a bicycle for more than a minute or two, run more than a 100 feet even though I once ran the mile in full combat gear and boots in just over six minutes. Because of my sleep disorder I can't even drive for more than about 30 minutes without the very likely consequence of falling asleep at the wheel. I tend to fall asleep in any situation that I find boring and driving is number one on that list.
About the only thing I have left to me that I do well is machining and related activities. Attack that and you attack all I have that is worth doing.

There you are: the cause, the symptom and the cure.

I put it down to the Northern hemisphere having a terrible Winter. Snowed in, rained on or Flooded out; it has got to be draining.
Perhaps it is taking its' toll on the emotional wellbeing as well??

Get over it.

It is a beautiful fine day here and I'm off outside on my crutches then into my wheelchair to tend the garden, try to introduce some order into the mess in my shed, make the handle for my welder, strip down a bicycle ........and count myself effing lucky to have life and what health I have.
I also get down at times but that is part of the cycle.

dan s
01-11-2009, 05:11 PM
Then start a new post titled "Everything You Need To Know About Insert Tooling" and point out how it should be done.
you post.lol I'm not that dumb, the "HSS is the only way" pundits would be all over me like a drunken sailor on an easy stripper.



You may also have to accept that different people find that insert tooling works better in conditions that aren't strictly textbook, and of course show that you're bothered when they disagree with what you post.
Peter,
I'm not referring to gray area stuff, like what insert shape is best for a given job. I mean when people screw up black and white stuff. For example I have read on more than one occasion (pretty sure in this forum) that the G in CCGT means ground. The G is nothing more than a tolerance designation. The fact that the only way that tolerance is currently reached is by grinding is irrelevant.

John Stevenson
01-11-2009, 05:24 PM
lol I'm not that dumb, the "HSS is the only way" pundits would be all over me like a drunken sailor on an easy stripper.




Seriously dan, that's not dumb, that's having conviction and knowing what you are talking about.
perhaps you won't convert everyone [ no correction you WON'T convert everyone ] but if you get your point of view over in a clear and concise manner then people will respect you for it and take note.

It is a grey area, there has recently been aa few articles, 3 consecutive ones I think, in MEW on just this subject

I must admit I didn't read them, not because I know everything, but because I'm tied into the fact i have at least 10 years supply of the inserts I use care off a large auction a few years ago.

But I say do your homework and go for it.

.

Doc Nickel
01-11-2009, 05:36 PM
lol I'm not that dumb, the "HSS is the only way" pundits would be all over me like a drunken sailor on an easy stripper.

-To add to what Jon said above, write your article to the average reader, not the loudmouths.

Look at the views vs. posts of the average thread- five or six posts, but fifty or sixty views. This board has a large number of quiet readers that post little, and just watch and soak up the knowledge.

I can't count the number of threads I've read, and learned something useful from, but didn't have a pressing need to post a reply to. The bulk of this site's readers are like that.

Personally, I know just enough about carbide to get by, but I'm always looking for more data- especially easy-to-digest stuff written for the home-shopper rather than the aerospace exotic-metals factory tool buyer.

Doc.

lazlo
01-11-2009, 08:22 PM
For example I have read on more than one occasion (pretty sure in this forum) that the G in CCGT means ground. The G is nothing more than a tolerance designation.

Most of the CCGT inserts you find are molded, and not ground. I think you may be referring to the CCGT aluminum inserts like the Kenametal CCGT-AK's, that are frequently discussed here. The CCGT aluminum inserts have a non-standard chip breaker with an extreme back rake and are up-sharp (honed) to a razor-edge, so they work great in soft materials, but they're very fragile.

I also use the SEHW aluminum inserts (can't remember their designation for up-sharp), which have the same extreme rake and honed edges, and they're just as fragile as the CCGT-AK's. Top right in this picture, compared with the normal SEHW left of it:

http://i164.photobucket.com/albums/u15/rtgeorge_album/SEHInserts023s.gif