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DICKEYBIRD
05-04-2008, 01:54 PM
I’ll preface this post with the statement that this project is still early days and if ya’ll see something I can add or modify (short of pitchin’ it in the trash) yell out.

It all started with a chance encounter at H/F with a 4” cross-slide vise on sale for $29.99. Here it is http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=538 I couldn’t pass it up for that price, even knowing up front it was just a kit. I had to straighten up several surfaces in the mill and added bearings to the leadscrew/handles. I did a little crude lapping of the dovetails and gibs and it moves pretty smooth now and appears to be fairly tight with the gibs adjusted carefully.

http://i57.photobucket.com/albums/g227/DBAviation/XYBrgParts.jpg

http://i57.photobucket.com/albums/g227/DBAviation/XYBrg.jpg

The next component is the 5C endmill sharpening fixture available from CDCO and many other places. Seems to me to be a good value at $32.00 and should guarantee the proper angles being ground into the ends of medium size 2 and 4 flute HSS endmills. It just occurred to me that the diamond wheel could be installed and carbide endmills could be touched up as well. I drew it up in CAD so I could visualize what would be needed to offer an endmill up to the H/F Baldor grinder clone at the proper angle. 4 - 3/8” UNC holes were drilled/tapped in the fixture so it could be bolted solidly to the vertical plate. The steel it’s made from is pretty hard and it was tough going but I got ‘er done with HSS tooling.

http://i57.photobucket.com/albums/g227/DBAviation/5CEndmillJig.jpg

http://i57.photobucket.com/albums/g227/DBAviation/EndmillSharpenercopy.jpg

DICKEYBIRD
05-04-2008, 01:55 PM
I printed out the sideplate drawing on the shop inkjet and glued it to to 2 pieces of 3/16” plate, bolted together with 10-24 c/sunk allen screws. This was clamped on the mill table and the slots and holes were machined easily and accurately. Once the holes & slots were completed, I put 2 - ¼” bolts & nuts into the holes so I could cut out the outer shape & finish up on the disc sander. Machining them as a pair insured accuracy. I took the trouble to machine the slots so it could be adjusted in & out for different lengths of endmills.

http://i57.photobucket.com/albums/g227/DBAviation/EndmillFixturePlates1.jpg

http://i57.photobucket.com/albums/g227/DBAviation/EndmillFixturePlates3.jpg

Rough measurements showed that the combined cross-slide/5C fixture would be too low if it was just bolted down and needed a spacer to bring it up to the grinder centerline. Eureka…the Grizzly mill vise rotary base was perfect for a spacer and would allow it to be swiveled for most any unknown future grinding chores. I’ll have to machine a plate to bolt to the cross-slide base with a slot milled in to fit the centering dowel in the vise rotary base. This will allow rotary movement and some back & forth movement.

http://i57.photobucket.com/albums/g227/DBAviation/EndmillFixtureMockup.jpg

http://i57.photobucket.com/albums/g227/DBAviation/EndmillFixtureMockup2.jpg

These pics are of the thing just mocked up and held in place by gravity so I still have a ways to go yet. I thought I’d post what I have accomplished so far to see what ya’ll think. It seems to be rigid & tight enough to be useful but that remains to be seen. I’m going to bend up some aluminum sheet covers for the exposed sliding surfaces and add a couple cheap dial indicators or digital calipers to accurately readout the movements. If the thing works OK, I may try to save up enough to get a CBN wheel instead of the soft A/O wheel.

I haven’t taken the time yet to work out how to gash the ends but hopefully, I can cobble up something.

DICKEYBIRD
05-04-2008, 02:30 PM
Your basic 5C spin-indexer bolts on nicely as well. Dunno if it'll do anything useful or not but looks the part anyway.;)

http://i57.photobucket.com/albums/g227/DBAviation/EndmillFixtureSpinDex.jpg

BobWarfield
05-04-2008, 05:04 PM
Getting quite the arsenal of machines there in your Grinding Department, DB.

When's the big belt sander coming? :)

I ordered steel for mine and a couple of flange bearings. It'll be a little while before I get started on it though.

Best,

BW

John Stevenson
05-04-2008, 05:13 PM
Wish I'd have thought of that ...........

.

DICKEYBIRD
05-04-2008, 05:15 PM
No belt sander in my immediate future Bob. Gotta stop these tool projects and actually make something more mainstream...like a steam engine, or a flame licker or....I'm thinking about joining A.T.B.A. (Amateur Tool Builders' Anonymous) so I can kick this addiction to building tools instead of making "real" things.;)

DICKEYBIRD
05-04-2008, 05:19 PM
Holy Cow, I didn't get a "clumsy bastid" out of Sir John...The dang thing may actually work!:)

John Stevenson
05-04-2008, 06:31 PM
Oh it will work.
Read post #8 in this thread dated 24 - 4 - 2003

http://bbs.homeshopmachinist.net/showthread.php?t=2424&highlight=tool+cutter

The link to the pic is broken due to change of ISP but the same picture is here.

http://www.stevenson-engineers.co.uk/files/T&Cgrinder.jpg


.

DICKEYBIRD
05-04-2008, 06:57 PM
Yup, I remember that pic well Sir J. I'm sure that's one of the many swirling images that was spinning around in my head when this project rose up from the murky depths. Looks like you made a bracket to mount the spin-dexer in the cross-slide vise jaws? I didn't have that much room so I just sawed off the movable vise jaw and mounted a grinding fixture bracket directly to the lower vice ways.

Anybody got any ideas how to gash an endmill after the end is sharpened? I have trained my brain to avoid all thoughts on that subject. It's easy, I just call up an image of Kiefer Sutherland in the old 70's movie Kelly's Heroes: "Hey man, stop with all them negative waves.":)

John Stevenson
05-04-2008, 07:01 PM
It was Donald.

.

DICKEYBIRD
05-04-2008, 07:05 PM
Crap! You're figgin' right. Brain glitch I guess...not enough pineapple juice in my pineapple juice this afternoon! No comparison between the Dad and his son.

BobWarfield
05-04-2008, 07:16 PM
One of the all time great WWII movies!

Have a little faith baby, have a little faith!

BW

quasi
05-04-2008, 07:48 PM
this post is like deja vu all over again!

tiptop
05-04-2008, 11:53 PM
It looks to me like you have everything you need to knash endmills except the proper wheel. You have pretty well covered your bases on angles and such. You will need a cup type wheel or I have used a cut off type wheel to get in close with. I have found that having a air bearing works well as most of the wear on my end mills occours at the edge rather than on the end. There are a couple of good articles in HSM on making them. You will probably want one sooner or later.
You are doing a nice job and keep posting pictures of your progress. Jay

lenord
05-05-2008, 01:26 AM
It looks like it can sharpen an end mill with little more effort on your part. Looks so good I may spring for the parts and copy your design. It looks like it's easily made and cheap, my two top concerns. The Lisle is $$$, even used off flea bay. The other ones I have seen look like they will take a while to make, lots of really kewl parts, but too time consuming to make.

But, how do you hold the 5C EMS fixture securely ?

Isn't the end mill suppose to be a some certain height in relation to the wheel ? How do ya figure that out and then keep the vise there ? Maybe some flat stock under it and a few bolts ?

How hard is it to put another fixture in the vise to sharpen drill bits ?
(I still can't sharpen them on a grinder). I have about 30 S&D bits that need sharpening......and that may more end mills. :eek:

Thanks
Lenord

DICKEYBIRD
05-05-2008, 08:03 AM
Lenord I drilled & tapped 2 - 3/8" U.N.C holes on the 2 seating faces of the 5C fixture. I figure 2 - 3/8" bolts will hold it at least as securely as a mag vise on a surface grinder would. That's how the fixture was originally designed to be used.

When I get it all finished, I'm going to try a couple of old drill bits using the endmill sharpening angles. That's one of the reasons I added the swivel base...so the fixture can be rotated around to the proper angle to do a "4-facet" grind on a drill.

T/T, if this thing works, I'll probably spring for a better wheel.

hwingo
05-05-2008, 10:09 AM
Dickeybird,

It looks like you've fabricated a triangular plate to add support to the feed screw.

How did you do that? What I am really asking is, how did you round the corners *and* how did you hold the piece so the plate could be milled? Did you simply place 3 holes in a round piece of stock then flatten the sides with the Mill or did you use a rotary table when flattening the sides. Mainly, I would love to know how you held the piece so it could be milled (???).

Harold

hwingo
05-05-2008, 10:26 AM
Well, after reading what I had written, it made little sense so I've changed sentence structure and I forgot to select instant notification.

Duh!!:o


Harold:)

DICKEYBIRD
05-05-2008, 11:00 AM
Hi Harold,

If you're referring to the aluminum bearing block in the 1st picture in the post, I started with an oversized square chunk of 1/2" aluminum clamped in the mill vise, drilled/bored the hole for the bearing, drilled the holes for the 2 mount bolts, cut the outside to rough shape on the bandsaw and refined it (incl. the radiused corners) on my home-made disc sander. I look for excuses to use my rotary table but in this case, I took the easy path.:) That disc sander has made my life a lot easier!

A.K. Boomer
05-05-2008, 11:41 AM
DB thats good stuff, I have that exact HF crosslide vise and went through it with similar mods,,, I used roller thrusts I had laying around --- This will kill you guys but HF's little drill press (there real little drill press) was my attempt at a milling machine, I got the cross slide for 30 bucks and paid just over 40 for the drill press, It shattered carbide like no tomorrow :o
But it did cut plastic -- sometimes... Hey -- a guys gotta start somewhere.:)

hwingo
05-05-2008, 04:18 PM
Hi Harold,

If you're referring to the aluminum bearing block in the 1st picture in the post, I started with an oversized square chunk of 1/2" aluminum clamped in the mill vise, drilled/bored the hole for the bearing, drilled the holes for the 2 mount bolts, cut the outside to rough shape on the bandsaw and refined it (incl. the radiused corners) on my home-made disc sander. I look for excuses to use my rotary table but in this case, I took the easy path.:) That disc sander has made my life a lot easier!


Hi Dickeybird,

Thanks for your explanation. Now, please explain your reason for using a bearing on the cross feed screw. How does placing a bearing on the screw improve things? I ask because I don't know.:o One would think that the design would be ok as is. Does the bearing make it feed smoother, or, does it add strength to the overall operation?

Thanks,
Harold

DICKEYBIRD
05-05-2008, 05:27 PM
Mine came with nothing to accept the thrust from the leadscrews on either axis, just metal on metal which added more backlash and tons of friction. After adding the bearings to both axes, the overall smoothness and "feel" is MUCH better. I was able to snug the gibs up a bunch and it still moves pretty smooth. Without the bearings, it was a joke trying to move either axis with the gibs tightened at all.

I suppose the mission could be accomplished without the bearings but it was pretty easy to make the mod...and I had the bearings lying around from my previous hobby. (Rear crankshaft bearing from a .45 cu. in Japanese r/c model aircraft engine.)

hwingo
05-05-2008, 10:13 PM
Mine came with nothing to accept the thrust from the leadscrews on either axis, just metal on metal which added more backlash and tons of friction. After adding the bearings to both axes, the overall smoothness and "feel" is MUCH better. I was able to snug the gibs up a bunch and it still moves pretty smooth. Without the bearings, it was a joke trying to move either axis with the gibs tightened at all.

I suppose the mission could be accomplished without the bearings but it was pretty easy to make the mod...and I had the bearings lying around from my previous hobby. (Rear crankshaft bearing from a .45 cu. in Japanese r/c model aircraft engine.)


Hi again Dickeybird,

I have more questions and would appreciate your “bringing me from darkness to light”. I have a keen interest in what you have done for more than several reasons. First, I am lacking in vision. My lack of vision is not because I am stupid, rather, my lack of vision is a direct result of ignorance, i.e., very limited contact with use of bearings. I openly admit to this. Ignorance can be corrected but stupidity can’t. My desire is to *learn* enough about the use of bearings that when thinking for myself, I can design “better mouse-traps”. Stated differently, I need to learn when bearings would be useful and how to utilize them. Others learn from personal experience and others learn when drawing on the experience of others.

From your explanation, I understand that the use of bearings have improved the workings of your apparatus. I think you have said enough that I can surmise why. What I would like to know is, was it necessary to press the bearing on the screw and is it necessary to press the bearing into the tri-lobed bracket that you fabricated. How do you know which member is to fit tightly with the bearing and how much “tightness” is required? Slip fit? Press fit?, Just slight interference? Slop? When would one contemplate the use of a bronze race rather than ball bearings?

If you had at your immediate disposal roller bearings and ball bearings, which would you have chosen for this project and why?

A second reason for asking these questions is, I have need for such a jig. I have the same indexer you have shown and all I need is the X-Y vise that you have shown. I would love to make this set-up if for no other reason ….. experience.

So I would greatly appreciate your taking the time to answer these questions. For that matter, I welcome a response from others as well.

Harold:)

oldtiffie
05-05-2008, 11:13 PM
It looks to me like you have everything you need to knash endmills except the proper wheel. You have pretty well covered your bases on angles and such. You will need a cup type wheel or I have used a cut off type wheel to get in close with. I have found that having a air bearing works well as most of the wear on my end mills occours at the edge rather than on the end. There are a couple of good articles in HSM on making them. You will probably want one sooner or later.
You are doing a nice job and keep posting pictures of your progress. Jay

You've got it right TT.

An air-bearing or similar is the way to go.

So far all that is being addressed is grinding the ends of the end mills where-as most of the wear is on the sides of the flutes. If you have got any more than say 1/16" (60 thou) of blunt flute you've got an awful lot of end-grinding to do. This even worse as it is quite likely that the end teeth edges are quite OK other than at the periphery.

Provide that the "Spin-dexer" or similar has very smooth easy-moving bearings and your machine bed longitudinal movement is equally smooth and light, you can simulate/emulate a tool and cutter grinder.

An end milling cutter is for all practical purposes just a smaller diameter but longer length version of a "side and face cutter". I don't think that many would consider sharpening the peripheral cutting edges on a S&F cutter by grinding the side faces!!

I suggest that the following Wikipedia article be read in some detail.

http://en.wikipedia.org/wiki/Milling_cutter

It not only shows but explains what "conventional" and "climb" milling are, but also the forces and processes in play and the need for "razor sharp" cutting edges - in both processes.

A blunt cutter will not only further over-load and blunt-en itself but will be to the detriment of the cutter, that milling machine and the work-piece.

I never put a blunt cutter away for use, consideration or sharpening later. As soon as I have finished with them - either because they got blunt during the job or where not sharp enough for another job - their fate is decided there and than - into the T&C bin for re-sharpening, hand-hone, the bin for re-use for other projects, or straight into the rubbish or trash bins.

I hand-hone the peripheral cutting edges on my end mills (all milling cutters actually). When they are past that stage they either get replaced or sharpened on my Tool & Cutter grinder.

DICKEYBIRD
05-06-2008, 08:25 AM
Tiff I have no aspirations to emulate a proper T/C grinder with this admittedly crude device. It's intended purpose is to (hopefully) freshen up the ends of worn HSS (maybe even carbide) 1/2" through 7/8" endmills. I have some that still have sharp side flutes but dull ends due to they way they were used. If the sides get worn, they're done. No way do I think I could build a proper machine to grind the sides.

Having said that, I hope it will also be useful in the future as a fairly precise tool to grip and grind some unknown widget into submission more accurately than the tools I have at present: my clumsy hands.;)

DICKEYBIRD
05-06-2008, 08:43 AM
What I would like to know is, was it necessary to press the bearing on the screw and is it necessary to press the bearing into the tri-lobed bracket that you fabricated. How do you know which member is to fit tightly with the bearing and how much “tightness” is required? Slip fit? Press fit?, Just slight interference? Slop? When would one contemplate the use of a bronze race rather than ball bearings?

If you had at your immediate disposal roller bearings and ball bearings, which would you have chosen for this project and why?
Hi Harold, sorry I'm so late with a response, I missed your question last night.

I turned & polished the leadscrew shafts down until the bearings would just slide on with no slop. The aluminum bearing brackets were bored for a light press fit and I just warmed them (the brackets) up with a heatgun and slipped the bearings in.

In my case, I chose ball bearings that will accept thrust loads in both directions (dunno the term for that) since it has to accept thrust loads from the leadscrew in both directions. For this low speed application, any old bearings that you can make fit would be fine.

Roller bearings or bronze bushings would require more work because a separate thrust bearing system would be needed.

Bill Pace
05-06-2008, 09:09 AM
I think I can see what you were/are aiming at with this rather ingenious set-up ... and, it should do that well.

To branch off further into doing the flutes would require a whole nuther angle of attack, and what you have there is not gonna contribute much to the construction of a means to get it. And I dont know that I agree that the flutes need more attention than the ends, I find I often bring an EM back by a quick pass over the cutting tips.

After seeing a couple other guys trying to make up an air spindle out of one of the 5C spin indexer, I thought it was a good idea and made a run at it ..... with only marginal success, -- they are precision tooling and dont tolerate sloppiness. I have since acquired a dedicated T&CG, the Cuttermaster, and can even more see the rather complex and far reaching requirements to get, what would seem on the surface to be, a simple grinding/sharpening of cutting tools.

As if one would need to be reminded of the far reaching needs to attain sharp cutters, I have been following Lanes building/rebuilding of a K O Lee to try and have it be a "cutter/grinder for all occasions" and it looks like something off the Enterprise in Scottys engine shop!!

hwingo
05-06-2008, 11:16 AM
Hi Dickeybird,

Really appreciate your reply. Slowly, my pea sized brain is forming images and acquiring a better understanding (I think:eek: ). Paraphrasing what I think I'm hearing you say, just because bearings have "pin rollers" or "balls", all of which are encased in a precision housing, in no way make them equal with regard to application. A thrust bearing functions differently than a roller bearing. Am I correct so far?

With regard to your application, you want the shaft to rotate smoothly (lateral forces??) yet require the bearing to reduce axial loads applied when advancing or withdrawing the lead screw making advancement or withdrawal easier.... especially when under a load. Is that correct?

Additional to the after-fore mentioned, the bearing will serve a function of significantly reducing or eliminating "back lash" when the screw is turned from one direction to the other. Is that correct?

So that I can "give" to this discussion ..... and not "just take", I would like to offer the following contribution. Years ago, during my doctoral training, I was required to be active in research (publish or perish!!). I ran across a company (Small Parts, Inc out of Miramar, FL 33027) that sold high quality parts (from A to Z) often used in scientific research. I have been dealing with these people for the past 30 years and I have grown to rely on them heavily. Among a plethora of things they sell bearings (metallic and non-metallic). The following links will give you an idea of what I am referencing.

http://www.smallparts.com/products/descriptions/br-%20bmr.cfm

http://www.smallparts.com/search/search.cfm

I highly recommend that you, and others, request of them a catalog that can be physically held in the hands. To peruse their web site sheds NO LIGHT on what these folks carry. It's amazing what you will find and quality is remarkable. I hope this to be beneficial in the future.

Harold

DICKEYBIRD
05-07-2008, 08:49 AM
With regard to your application, you want the shaft to rotate smoothly (lateral forces??) yet require the bearing to reduce axial loads applied when advancing or withdrawing the lead screw making advancement or withdrawal easier.... especially when under a load. Is that correct?

Additional to the after-fore mentioned, the bearing will serve a function of significantly reducing or eliminating "back lash" when the screw is turned from one direction to the other. Is that correct?

http://www.smallparts.com/products/descriptions/br-%20bmr.cfm

http://www.smallparts.com/search/search.cfm
Yessir, that was my thinking.:)

Unfortunately there's still a lot of backlash in the leadscrew/slide threads due to a very sloppy fit in the threads. I decided to leave that alone since, for me, there has to be a limit to the time & money spent trying to make it something it will never be. The backlash shouldn't be a problem in this application since one axis will be locked down solid and the other snugged up as much as possible and the slide will only be moving in one direction when the tool is being ground. There are far better X/Y slide units available that don't have these problems, but not for $29.99.

Great links! The BR06 bearing should work fine. I would order a catalog but there's so much neat stuff there I'd be ordering too many things I can't afford.;)

Milton

Norman Atkinson
05-07-2008, 09:01 AM
I have a Quorn- no air whatsit
I have a Stent- no air whatsit
I have a Kennet- no air whatsit

I also have a Clarkson who made tool and cutter grinders. Clarkson made cutters- of which you all should be aware.
Mine and I have the manual- makes no provision for air whatsits.

For my pains, I subscribe to YahooGroups Quorn_owners.
There is a lot of hot air but the cold air to these air whatsits is far from 'being in the right place, at the right time'

Now as we all proceed along a branch, the branch gets thinner.
Perhaps we could all get air mattresses to cushion(oops) the blow( more oops)

Let's get real?

Norm

Mcgyver
05-07-2008, 09:22 AM
Norm, seems you have all the peripherals.....now just get a whatsit, you'll be pleased that you did. The great model engineers of yesteryear gained their status with treadles, but I don't feel less of man for wanting my electric motor :)

hwingo
05-07-2008, 09:53 AM
For the love of Pete, what is a "whatsit:eek:

Harold

Norman Atkinson
05-07-2008, 10:08 AM
Commonsense suggests that if there is something that one doubts its usefulness or even possibility, it is fair to call it a whoosit or a whatsit.

Quorn_owners has waxed long and lyrical about trying to get an air rotavotor to work.

The great minds who like me started on a threadle lathe never got a 'roundtuit' either. They designed everything that we have got now- and let's face it, this forum is redolent( nice word) with questions about how the stuff just after they motorised after abandoning their treadles, works.

Just call me a septic! In fact I am a sceptic septic!!!!!!
So there.

Mumble mumble!

Norm

JCHannum
05-07-2008, 10:12 AM
For the love of Pete, what is a "whatsit:eek:

Harold
It is an air bearing spindle for sharpening the flutes of end mills and such. It is a nice accessory, but I agree with Norm, somewhat overrated.

Norman Atkinson
05-07-2008, 10:48 AM
Hooray for Jim!

OK, fellas! Of course I know all about air drills- my wife is No2 Lady Fellow of the Royal College of Surgeons in Dentistry in Edinburgh and my daughter is following and one off consultant. Son in law is a cardiologist. Fine but here we have in blue corner a cheap sh1te grinder made out of scrap from the harbour in HongKong and others are talking about fitting air driven spindles to rotate a drill and costing more money than the American National Debt.

To be fair, I made a grinder like that one. Milled the vice off and put on a sub table to exclude the grit- blah, blah! And then someone had a Clarkson for $200 and round the corner!.The bloody pedestal was about the same weight as the Statue of Liberty- and I gave the guy it to weigh in for scrap for lifting the rest of it into my--------Skoda!

It was only a few days ago that Sir John's Odds and Sods adverts brought up a Stent. It was around the corner and was the princely sum of $300 complete with motor, grinding wheels and a poster with a Spitfire on it with
'Nil Illigitimi Carborundum' on its nose. Heave ho, into the Sanctus Sanctorum and . well, this is fun! The Stent, I shudder to admit, was not made of approved castings but welded up out of mild steel.

Air rotors???? Does anyone appreciate that they invented by Hero of Alexandria? I did all this in 1944!
Sorry,and all that

Norm

Dawai
05-07-2008, 10:52 AM
OOKS like to me.. one of you genius'es would have done a cnc tool sharpener by now.

Considering I spent about $400 on endmills a year or so back and didn't get much more than a handfull.

I powered up a HF 4" indexer for such a purpose.. I got dead end mills everywhere.. now if I could just talk that old bridgeport into sharpening them itself?

Norm.. take your meds..

Norman Atkinson
05-07-2008, 11:32 AM
Ah, David, you forget that I am just the peasant boy. None of this CNC stuff but you see me with a slate and chalk. You see once Euclid and me got our heads together, the world was at our feet.

That new boy called Leonardo da Vinci did a lot on grinding.Time you read him up. Nah, not the Dan Brown thing but doing up armour and things.
The hint is that he was left handed and you'll need a mirror to read it.

I keep forgetting Archimedes- he was into spirals.

Medicine??? No fear, alcohol- YES!!!!!

What happened after I left school at 14- did it all go back to the Dark Ages?

Take care, lad

Norm

lazlo
05-07-2008, 11:40 AM
It is an air bearing spindle for sharpening the flutes of end mills and such. It is a nice accessory, but I agree with Norm, somewhat overrated.

An air-bearing is really for sharpening the side flutes. It's very difficult to get the endmill to rotate through the helix angle without stiction without an air bearing. If you get any stiction at all, you end up nicking the flute.

Phil Duclos has an air bearing project in HSM magazine. Lane built one -- you can see it on his web page:

http://www.cp-tel.net/mary/LanesPhotos/LTooling1.JPG

Then Glenn Wilson included a slightly improved version of Phil Duclos' air bearing on his miniature Cuttermaster clone (tool and cutter grinder) project, and the "Much Improved Quorn" articles included a build of Glenn Wilson's version of the air bearing.

Building an air bearing seems like one of the most challenging projects in HSM. The bore has to be straight and round within something like 2 tenths along 4". Several people on the Quorn group have tried to build one, but the bearing wouldn't float without excessive air pressure.

I have a K.O. Lee air bearing fixture, but one of these days I want to try building Phil/Glenn's design, especially since I just bought a benchtop Sunnen hone :)

BobWarfield
05-07-2008, 11:53 AM
Careful of all this blather, the trolls will hear and come runing.

BW

Norman Atkinson
05-07-2008, 12:24 PM
Hi Robert,
If you recall, I did say that a Stent could be fabricated. This guy certainly proved it. 'Popped his clogs' but I have quite a toy!

This air bearing! I was going on a bit about Archimedes. I was trolling!
If I recall, the principle that Prof. Chaddock adopted was a piece of string/cord and the lot was wrapped around the chuck and a weight at the end. So it is back to Archimedes as he 'invented the screw'

I keep telling you lot, it is all been done before. You lot are simply making it difficult!

OK, fellas light the pyre! Heretics, form an orderly spiral?

Norm

lazlo
05-07-2008, 12:34 PM
Careful of all this blather,

Who's post is the blather?

TGTool
05-07-2008, 05:45 PM
Building an air bearing seems like one of the most challenging projects in HSM. The bore has to be straight and round within something like 2 tenths along 4". Several people on the Quorn group have tried to build one, but the bearing wouldn't float without excessive air pressure.


There's been an apparently quite successful air bearing posted recently on the Quorn Yahoo group so maybe he points the way to other applications. Video's show it supporting a couple kg several inches out from the housing and rotating freely on as little as a couple atmospheres.

davidwdyer
05-07-2008, 07:25 PM
Has anyone tried to use a 5C spin-indexer instead of an air bearing? The one I have seems to have almost no play.

Could it not be modified to use with a surface grinder with a little rod to stick in between the flutes and turn it?

Maybe some has already tried this.

New chips
05-07-2008, 08:29 PM
I have one of the X Y drill vise from HF as well. I was able to adjust out the play on the top axis but could not figure out how to take the bottom axis apart to stone and adjust. The lead screw would not come out. How did you take your bottom axis apart?

oldtiffie
05-07-2008, 08:47 PM
Has anyone tried to use a 5C spin-indexer instead of an air bearing? The one I have seems to have almost no play.

Could it not be modified to use with a surface grinder with a little rod to stick in between the flutes and turn it?

Maybe some has already tried this.

Hi David.

There is no real reason why an accurately machined and low-friction "Spindexer" with collets mounted on a surface grinder could not work as a tool and cutter grinder when mounted on a good surface grinder. It will require a bit of work and care but the basics and fundamentals are there.

This is my surface grinder which is a very nice piece of machinery and it is very accurate and as smooth as silk.

http://www.machineryhouse.com.au/Products?stockCode=G202

http://i200.photobucket.com/albums/aa294/oldtiffie/Surf_Grinder1.jpg

All that is required essentially for grinding the spiral flutes of an end-mill or slab-milling cutter is a machine which has a very low co-efficient of friction both axially (along the machine) and rotationally (around the axis/centre of the end mill or the spindle/mandrel) so that the cutter will move extremely/very smoothly as the cutter follows a spiral path as it passes the grinding wheel.

A slab-cutter and side-and-face cutters are mounted on a mandrel, hobbing cutters are mounted between centres and and end-milling cutters are mounted in collets (usually) in the rotating head.

http://i200.photobucket.com/albums/aa294/oldtiffie/Stub_arbor1.jpg

When I was Tool & Cutter grinding in the Tool Room I was using a fabulous (USA) "Cincinnati" (Sp?) T&C grinder. The bed ran on balls and rollers and the rotating head had no evident axial or radial "play" but was as light and a smooth as silk. It did not have an "air bearing" as they were not available then (50+ years ago).

I have a Chinese clone of the US "Cutter-Master" (Sp?) T&C grinder and just about all of the attachments. It has an air-bearing which as lazlo says is a superb piece of engineering. It is lapped (female) and precision ground and lapped (male/spindle) and is an extremely close sliding fit. It is difficult to assemble and great care is needed. The head is supplied with a constant flow of air from my compressor. That spindle will slide to the end of its travel at a grade of less than 1/8" per foot (1:96)!!! and if tilted and not constrained will fly out of the housing. It has no/negligible "play" at its ends when extended 8" + from the head. It only requires a very light oil in terms of viscosity and volume. I have an oiler in the air supply circuit.

The air spindle referred to in tool and cutter grinding is not a high speed "motor" as used in die-grinders or dentists drills etc. as Norm seems to have advised.

My T&C grinder is at:
http://www.machineryhouse.com.au/Products?stockCode=G196

[url]
http://i200.photobucket.com/albums/aa294/oldtiffie/ToolCutter_Grind1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Stub_arbor1.jpg

The makers code is CT-610:
http://www.chitseng.com/main2.htm
http://www.chitseng.com/product2.htm
http://www.chitseng.com/product5.htm

lane
05-07-2008, 09:42 PM
OK Ok I got a Qourn A piece Of S--T You want to grind end mills . Buy a cutter grinder . Even a Darex E90 , a Cutter Master will do get a surface grinder with a Waldon air bearing fixture and a cup wheel Their are all kinds of ways to come up with something. Besides with coming up with something that will only half way do the job. I still like what Dickeybird built it shows that he is trying . keep up the good work.I did the same thing when I started out. build what I aint got Untill i can get better.

DICKEYBIRD
05-07-2008, 10:19 PM
...it shows that he is trying.Funny, that's the SAME thing my wife says: "You're trying...VERY trying!" ;)

Seriously though, thanks for the kind words Lane. You're very right; I build what I can afford, which ain't much right now but I am learning and having fun. So far, every last piece of tooling I have built has an almost uncanny way of either doing the job it was meant to do of if it fails, it shines at another task later on. That's why this one is being made as adjustable as possible. Who knows what rocket surgery it may perform next year?;)

dp
05-08-2008, 01:53 AM
Hi Dickeybird,

Thanks for your explanation. Now, please explain your reason for using a bearing on the cross feed screw. How does placing a bearing on the screw improve things? I ask because I don't know.:o One would think that the design would be ok as is. Does the bearing make it feed smoother, or, does it add strength to the overall operation?

Thanks,
Harold

I have that same model. If the feed screw is anything but perfectly aligned with the nut it will bind. There's enough slop in the plate to allow the screw to twirl as you turn the crank and the motion is extremely uneven. The bearing prevents that twirling and the action is vastly improved.

It's a very heavy lump and the dovetails are substantial. It is generous to call them gibs - I've seen smoother skids on logging sledges; lapping them is beneficial.

It can be further improved by replacing the miserable screws with well made acme thread. Mine are poorly plated with something that resembles chrome and for the most part I don't recognize the thread type as they're so badly made. The dial is without doubt the kruftiest such thing I've ever seen and completely useless. After all the rework it is actually a rather decent tool for the drill press.

Norman Atkinson
05-08-2008, 02:46 AM
Old Tiffie,
I have your grinder. Well, not quite. Mine is the £150 or$300 version and is called a Stent which is a 'baby' Clarkson. Earlier, I did say that I also had a Clarkson which cost £100 or $200. So. apart from the disparity in prices, we are pretty much alike. Our differences lie in a means of evenly rotating a flute in the process. I simply cannot justify the purchase of an exceedingly expensive bit of kit and having to supply an air supply into the bargain. Sorry, me old mate, but I'm a bleedin' bean counter.

As for comments about the Quorn, I do think that Lane is almost correct about the complexity of the Quorn. Mine is 'under the bench' Like my comments to OT ealier, I am a bean counter and there is an easier way.

So let's move on. In the Sanctus Santorum- or me shed, I have a Kennet.
Also by Model Engineering Services in the good old UK. The geyser who seems to run the show- or part of it was at the Society of Model and Experimental Engineers stand at Harrogate. He was using the very basic Kennet. He, like me, was using the 'easier' way or machine for everyday use.
His Quorn came out on feast and holy days!

Now, if you will excuse me, I have a possible row with Quorn-Users brewing.
Meantime, have fun!

Norm

DICKEYBIRD
05-17-2008, 03:18 PM
This morning I got the PMTG (Poor Man's Tool Grinder) finished enough for a trial run. I still have dust covers to make and dial indicators to mount but I couldn't resist trying it out. I bolted it down to the grinder table and aligned it so the X-axis is parallel to the face of the wheel and dressed the AO wheel with a diamond sharpener. It controls the movement of the tool very smoothly with good precision. Stepper motors under CNC control would be nice but hey, my funds are very limited.:)

I didn't want to try a real endmill 1st time out so I ground the end of an old 7/16" drillbit flat and tried to make a 2 flute endmill out of it. I got pretty close by eye with no measuring but it still has a little nubbin right in the center. It's hard to get a picture to show it though.

http://i57.photobucket.com/albums/g227/DBAviation/EndmillSharpen1.jpg

There's some basic rule of sharpening I'm missing here. Does anyone have a favorite book or website with the basics of tool grinding? I'd like to know the correct order to grind the angles and how to get the edges symmetrical. I'm happy with how the original idea turned out and I think it will work fine with further refinement of the operator's skill. Any words of wisdom from tool grinding vets?:)

tiptop
05-17-2008, 04:46 PM
Milton and everyone,
I had this in the other thread started by Milton and thought I would copy it here for those of you that are interested.

I have posted some pictures at my imagevent site, showing the Air Bearing fixtures made by Cuttermaster and Harig that I have. These are just for the proverbial "food for thought" crowd. Not trying to steal the thread Milton, I just figurered some of these folks may be interested, since you have them walking down the road, so to say.

Here is a link to them.

http://imageevent.com/aatiptop/tools...ndcuttermaster

John Stevenson
05-17-2008, 06:45 PM
I got pretty close by eye with no measuring but it still has a little nubbin right in the center. It's hard to get a picture to show it though.

http://i57.photobucket.com/albums/g227/DBAviation/EndmillSharpen1.jpg


That's because you have ground the cutter symetrical.
The front 'nicks' have to be ground one longer that the other to force one face to also be longer.
The idea is to get one face longer so there is no pip and it can centre cut.

BTW that's now three of these running with the Chinese XY tables and a spindex to make a grinder.

DICKEYBIRD
05-17-2008, 06:49 PM
Da-yum...ya' learn somethin' new every day! Thanks. :)

lazlo
05-17-2008, 06:57 PM
BTW that's now three of these running with the Chinese XY tables and a spindex to make a grinder.

You going to start charging royalties John? :)

John Stevenson
05-17-2008, 07:40 PM
No Lazlo, I'll wait until the CNC tool and cutter grinder that uses 3 off the shelf modules comes out.
Then I'll retire to my rocking chair and rake it in :D

Then again it may come to a store near you as the Chinese are interested in the concept.

I'm over to China again in 3 or 4 weeks and it's on the list.


.

oldtiffie
05-17-2008, 08:35 PM
I got pretty close by eye with no measuring but it still has a little nubbin right in the center. It's hard to get a picture to show it though.
http://i57.photobucket.com/albums/g227/DBAviation/EndmillSharpen1.jpg


That's because you have ground the cutter symetrical.
The front 'nicks' have to be ground one longer that the other to force one face to also be longer.
The idea is to get one face longer so there is no pip and it can centre cut.

BTW that's now three of these running with the Chinese XY tables and a spindex to make a grinder.

That is a nice job DB - very.

Just a couple of comments and suggestions.

What you are doing is generally fine as you have provided a cutting edge with - say - 5 to 10 degree "front clearance" as well as relieving the back/shoulder (say 15 to 20 degree) to provide clearance.

My guess is that that the cutting edges are square (90 degree) to the drill centre-line. That's fine for using the drill for flat-bottoming or counter-boring - just as it is. The "little nubbin" in the centre is of no consequence as it will be in the "pilot" hole or clearance hole for the bolt or screw if it is for use as a counter-bore.

If it were an end-milling cutter the cutter grinder should be set so that the cutting edges are 1 to 2 degree off "square" so that you will have an included angle of say 176 to 178 degree so that the cutter is only cutting at the "points". If you put a straight edge over the ends of opposite teeth on a end-mill cutter you will see that the cutter only "touches" on the "points".

John Stevenson is correct if you want to "plunge" cut without a pilot hole.

You can get rid of the "nubbin" just by hand-grinding (by eye is good enough - either on the corner of a wheel on a pedestal grinder or by using a die-grinder or a "Dremel" or the like.

I would pay attention to the face of your "cup wheel" that you are using. Keep it "dressed" so that it remains "sharp" and cuts easily and does not "rub". "Rubbing" overloads the wheel which in turn over-heats the work being ground.

Dress the wheel so that you only have a 1/8" "land" in contact with the work-piece - it will work much better. Go as quick as you can as going "slow" or "dawdling" can cause heating as well.

There is nothing wrong at all with an Aluminium Oxide (AlOx) wheel as you have for HSS. It will work fine. Just keep it "dressed" and "sharp". A diamond wheel is not needed for High Speed Steel (HSS).

A "green" (silicon carbide) wheel will "do" for tungsten carbide tips most times. Sure, you are going to have to re-dress them more frequently and perhaps get through more "green" wheels but they are a lot cheaper than diamond or its equivalent "boron" wheels.

If you don't have a diamond dressing rod (which are not too dear and with care will last you almost forever) just use an emery "dressing stick" that you can buy at any good hardware store. They work well and last for-ever. I use a diamond dresser on my surface grinder and most times on my tool & cutter grinder. I use the emery dresser to "shape" my T&C grinder wheels and to put the relief on to get the "land" I want.

That "X"/"Y" table and "Spindexer" units you have are very handy units. I have used both on my rotary table as well as on my pedestal drill at times. The XY table "end-play" at the ends of the lead-screws takes some getting used to as does the "rough and ready" dials, but under-neath it all is a pretty good and useful unit.

You are doing very well. The way you have used your "stuff" is a good example of "lateral thinking" and it works!!

DICKEYBIRD
05-18-2008, 12:05 AM
Thanks 'Tiffie. I'm cautiously optimistic about the thing now. With some more learning, I think it's actually going to do useful work for me. I need to catch a plane to Nottingham and swap Sir John a couple racks of Memphis barbeque ribs for an hour or 2 of concentrated tool grinding lessons.:)

The slight concave effect of the cutting edges you mentioned is there, just hard to tell in the picture. That 1 or 2 deg. angle (not sure exactly) as well as the clearance and relief angles are all built into the collet fixture by it's manufacturer. Takes out all the guesswork.

oldtiffie
05-18-2008, 12:24 AM
Thanks DB.

The wheel you have in your pic is mainly for grinding stuff like drill bits and wood-working chisels etc.

http://i57.photobucket.com/albums/g227/DBAviation/EndmillFixtureMockup.jpg

There are lots of profiles of AlOx wheels "out there" although many will have the standard Tool Room grinder 1 1/4" (31.75mm) bore. Many come with "plastic/nylon?" sleeves (tubes) to "bring it down" to most common grinder shaft/spindle diameters.

Some of the types available are:
http://i200.photobucket.com/albums/aa294/oldtiffie/Grinding_Wheels/Grinding_wheels1.jpg
http://i200.photobucket.com/albums/aa294/oldtiffie/Grinding_Wheels/Grinding_wheels2.jpg
http://i200.photobucket.com/albums/aa294/oldtiffie/Grinding_Wheels/Grinding_wheels3.jpg
http://i200.photobucket.com/albums/aa294/oldtiffie/Grinding_Wheels/Grinding_wheels4.jpg
http://i200.photobucket.com/albums/aa294/oldtiffie/Grinding_Wheels/Grinding_wheels5.jpg
http://i200.photobucket.com/albums/aa294/oldtiffie/Grinding_Wheels/Grinding_wheels6.jpg

I'd suggest "cup" or "saucer" wheels. "Medium" grade is quite sufficient as an "all-round" grade. Get sizes to suit your grinder. These wheels are ideal for forming (by "free-hand") "lands" on.

http://i200.photobucket.com/albums/aa294/oldtiffie/Grinding_Wheels/TPG9.jpg

I wouldn't get "hung up" on wheel speed either. Perhaps its better faster in a commercial shop, but the slower speed will work OK. Might have to dress the wheel a bit more often - so what of it? As long as it does the job - which your machine will - then all is OK.

oldtiffie
05-18-2008, 12:43 AM
Thanks 'Tiffie. I'm cautiously optimistic about the thing now. With some more learning, I think it's actually going to do useful work for me. I need to catch a plane to Nottingham and swap Sir John a couple racks of Memphis barbeque ribs for an hour or 2 of concentrated tool grinding lessons.:)

...............................................
.

Thanks DB.

While you are talking to John Stevenson, I'd suggest you ask him about and how to get the very good CD on "Tool & Cutter Grinding" that he/his wife sells on the web - used to be eBay but not now. Perhaps when John reads this he will post the address of his/her site.

I have a copy if that (very cheap and very good value) CD and while it is for specific machines and general principles, the info is there.

I hope it helps.

DICKEYBIRD
05-18-2008, 06:53 AM
I'm sure you're right about the cup type wheels 'Tiffie. Thanks to a very kind and gracious forum member, I'll have a few different ones to try out soon!:)

Swarf&Sparks
05-18-2008, 11:47 AM
No milling cutters, but some good info on drill geometry here
http://www.mmsonline.com/articles/068901.html

clutch
05-18-2008, 06:40 PM
I'm sure you're right about the cup type wheels 'Tiffie. Thanks to a very kind and gracious forum member, I'll have a few different ones to try out soon!:)

But your hub uses screws and not a locking ring on threaded center of hub like a surface grinder.

Clutch

DICKEYBIRD
05-18-2008, 07:15 PM
I'll figger out sumthin'. :)

Chipslinger
05-18-2008, 07:16 PM
[QUOTE=JCHannum]It is an air bearing spindle for sharpening the flutes of end mills and such. It is a nice accessory, but I agree with Norm, somewhat overrated.[/QUOTE

Unless you pick one up at a garage sale or auction for 20 bucks.

JCHannum
05-18-2008, 07:21 PM
I agree with that. I got Cuttermaster air spindle at auction for $5.00. It had a well tooled KO Lee T&C grinder attached as well.

Alistair Hosie
11-19-2009, 04:39 PM
pics please .Alistair.

Alistair Hosie
11-19-2009, 04:42 PM
sorry comps gone wonky

70 malibu
11-19-2009, 07:20 PM
Yup, I remember that pic well Sir J. I'm sure that's one of the many swirling images that was spinning around in my head when this project rose up from the murky depths. Looks like you made a bracket to mount the spin-dexer in the cross-slide vise jaws? I didn't have that much room so I just sawed off the movable vise jaw and mounted a grinding fixture bracket directly to the lower vice ways.

Anybody got any ideas how to gash an endmill after the end is sharpened? I have trained my brain to avoid all thoughts on that subject. It's easy, I just call up an image of Kiefer Sutherland in the old 70's movie Kelly's Heroes: "Hey man, stop with all them negative waves.":)
I think you mean Donald Sutherland,,, Kiefer was only 4 years old in 1970.

Great movie !!!

DICKEYBIRD
11-20-2009, 05:24 AM
Sheesh, dredging up old threads to point out my mistakes!;)

Besides, Sir John corrected me in post #10.:)

John Stevenson
11-20-2009, 08:27 AM
I am actually pleased this got resurrected because ther is another post on the 5C sharpener running at the moment and I have just been sent two from China.

I'd also like to add something to this post later but working day at the moment [ well dinner actually but a cup a soup, because of this abscess isn't really dinner ]

DICKEYBIRD
11-20-2009, 11:26 AM
I'd also like to add something to this post laterAWRIGHT! (Rubbing hands together and waiting anxiously.) Oops, I'll have to catch up later....gotta install a new front storm door and then help #2 daughter move into her new apartment.

John Stevenson
11-21-2009, 06:59 AM
Your basic 5C spin-indexer bolts on nicely as well. Dunno if it'll do anything useful or not but looks the part anyway.;)

http://i57.photobucket.com/albums/g227/DBAviation/EndmillFixtureSpinDex.jpg
Without any sort of tilt arrangement on the Spindex all you can do is flat grind the ends.

However if you present the cutter onto it at above or below centre the diameter of the cutter comes into play and applies the necessary clearance.

Some T&C grinders work this way, they have no tilt facility and rely on the wheel for the clearance angle, Boxford is one.

http://www.stevenson-engineers.co.uk/files/Toolangle.jpg

There is another chart I can't lay my hands on that allows you to do the ends using the outside of the wheel

.

DICKEYBIRD
11-21-2009, 08:15 AM
So I would need to rotate my Spindex 90 deg. and this setup would be used to sharpen milling cutters that are used mostly on horizontal mills? Pretty cool that!

John Stevenson
11-21-2009, 08:29 AM
Yes and once I find the other table the same setup, 90 degrees rotated from the picture, will enable you to do the ends on end mills without that 5C jig.

DICKEYBIRD
11-21-2009, 08:38 AM
Thanks John, I hope you can find it.:)

I also missed the fact that my above query was my 1000th post. Look out Evan, I'm catching up to yer!;) Now where's that bottle of bubbley, time for a Sat morning Mimosa.