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dockrat
11-07-2009, 05:18 PM
Tailstocks seem to be the topic today so in keeping with that, here is my tailstock rant. My lathe is a chicom BVB25L (Tiffie, it’s the same as yours) As a hobby lathe it is adequate except for the tailstock. Whoever designed it for this lathe should have it tied to an ankle just before he goes for a swim. The saddle on this lathe is so wide that the tailstock will not reach across it . In order to use the tailstock I have had to add an mt2 to mt2 adaptor. So although I get no rotational deflection I do get lateral deflection. A few pictures to show you what I mean.

Here is the tailstock right up against the saddle with the ram retracted:

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1327Medium.jpg

And again with the ram at full extension:

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1330Medium.jpg

The ram with the adaptor. Way too unsupported, hence the deflection.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1331Medium.jpg

What a POS eh? One day when I feel capable to do so, I am going to bite the bullet and cut off the top of that tailstock and try to make something better. John, Brian, Anyone??? Have you got a good design???

John Stevenson
11-07-2009, 05:23 PM
Any chance of a picture of the saddle without the toolpost and tailstock in the way ?

dockrat
11-07-2009, 05:38 PM
Any chance of a picture of the saddle without the toolpost and tailstock in the way ?

Sure.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1333Medium.jpg

Walter
11-07-2009, 05:41 PM
Dockrat,

What about making an extended ram for the tail stock, I'd think you'd probably eliminate some of that deflection at least...

Jim Caudill
11-07-2009, 06:51 PM
Hardinge is guilty of doing the same thing.

John Stevenson
11-07-2009, 07:10 PM
Many makers are, my small TOS is very similar.
There are some machines that have remedied this by overhanging the tailstock nose.

Dr. Rob
11-07-2009, 08:08 PM
Looks like the total range of movement is like 40 mm. That is just really strange. The tailstock body looks like it would be about 150 mm.

Maybe the screw is just too short, and the guy who assembled the machine just didn't care.

Take the thing apart and see if you can't fit a longer screw inside.

.

J Tiers
11-07-2009, 08:33 PM
What is the ram length? How far in can it go?

Some of the old-time lathes that came from a watchmaker's lathe background had some WAY long rams, with really long supports as well.

Of course, the whole tailstock ram is a kludge, its about the only part of the machine that should have some sort of gibbing, but it does not due to being round.

There is NO adjustment for wear. And it is difficult to see how to make one that is sensible. One could do a design somewhat like an ER collet, clamping inwards as an adjustment collar is tightened. I've never seen one, but I;d be surprised if it was never done.

But most machines don't have that, and don't even have ram wipers. So from day one, the ram gets looser and looser, more and more wiggly, sloppy, and imprecise. Bellmouthing is the order of the day.

Now, there is NO particular reason that the ram HAS to be round, and no particular reason it must be enclosed in a tubular part of the tailstock, either. It never turns except in a watchmaker's type lathe, all others have some form of key.

It could easily have been made like the ram of a shaper, with dovetail ways , or square ways. That wouldn't bother the action at all, but that is not the traditional way to do it.

This is a case where tradition should have been broken long ago. But as far as I know, not ONE lathe maker ever made a non-round tailstock ram. If any did, I'd love to see a picture, because they would be the only maker that had the brains to see past tradition and easy manufacturing and focus on function. But they were probably punished by the market for being so sensible.

Andrew_D
11-07-2009, 08:46 PM
Now, there is NO particular reason that the ram HAS to be round, and no particular reason it must be enclosed in a tubular part of the tailstock, either. It never turns except in a watchmaker's type lathe, all others have some form of key.

It could easily have been made like the ram of a shaper, with dovetail ways , or square ways. That wouldn't bother the action at all, but that is not the traditional way to do it.


Actually, I was trying to think of ways to improve the side-to-side adjustment on my little 7x SIEG lathe and after looking at it for a while and reviewing the many different ideas on the ole WWW, I've decided that I am going to rebuild from scratch.

Now keep in mind, I haven't done it yet (haven't got me one of them round-tuit's!), but my idea was to use dovetails on the side-to-side adjust (with a screw for movement) and dovetails on the ram-in-out. I was originally thinking a square ram, but figured the dovetails would be better since they are adjustable and (reasonably) easy to make.

Great minds think alike!

Andrew

J Tiers
11-07-2009, 08:48 PM
Smart man! ;)

Black_Moons
11-07-2009, 09:09 PM
Iv thought of replaceing the pin in the tailstock with a wedge shaped key that would be held in a precision slot in the tailstock with gib screws behind it.. that would compensate for wear and help wedge the ram in place against the top of the ram bore. But I like the dovetail tailstock idea more :)
mmmm.. very temping to make my own tailstock sometime in the future.. if I only I had the castings

darryl
11-07-2009, 09:14 PM
Hmm. That's got me thinking- I was actually needing a support, a steady rest I suppose, where there could be some motion like a dovetail slide. For my use, I would have machined the business end of that with a tool held in the chuck. Anything turned to fit that business end would be about as on-axis as you could get.

And guess what- the thing I did make has a round ram just like a tailstock. Sometimes its hard to see out of the box.

dockrat
11-07-2009, 09:28 PM
Dr. Rob....the total travel is 1 7/8" (47.6mm)

Jerry....over all length of the ram is 5" and it will retract into the tailstock body by 1/4"

I don't think a longer screw is the answer. With that 5" ram I think you would need at least 3" of the ram inside the tailstock for support. The real answer is a longer tailstock body WITH a longer ram.

J Tiers
11-07-2009, 09:40 PM
Dr. Rob....the total travel is 1 7/8" (47.6mm)

Jerry....over all length of the ram is 5" and it will retract into the tailstock body by 1/4"

I don't think a longer screw is the answer. With that 5" ram I think you would need at least 3" of the ram inside the tailstock for support. The real answer is a longer tailstock body WITH a longer ram.

The Logan has a 5.25" ram, and the housing is 6". The ram does not retract inside, it only goes to flush, which is enough. Total travel is about 2.375", at which point slightly over half the ram is still inside. It isn't enough, the slop gets rapidly worse near full extension, although it is nearly non-existent in the first 0.75" of travel. I've been meaning to do something about it, but I actually have not even assessed the conditions yet. I just do my work-arounds.

I'm with you on both points.... the ram needs as much as possible inside teh barrel for stability. The lever is a multiplier for slop..... if you have only 0.002 slop, and the ram extends half it's length, the slop at full extension is 0.004. More is clearly NOT needed.

A considerably longer ram would have to wear a lot more to get to the same slop. But it would have less force on it, and therefore might actually wear slower, due to the reduced lever arm.

yes, the longest ram, with the longest tailstock barrel is best. That would give the smallest 'slop multiplication" possible, and the best performance of a round ram.

It would be the same with a dovetailed ram, but at least there you could adjust the slop with gibs.

Robin R
11-07-2009, 09:52 PM
It sounds like J Tiers is describing a bed turret, see the second picture from the bottom. http://www.lathes.co.uk/hardinge/page4.html

Black_Moons
11-07-2009, 10:21 PM
Btw dockrat, Why do you need a center on such short parts?

tdmidget
11-07-2009, 10:25 PM
Tailstocks do not have rams, unless they are also shepherds and have a male sheep. They have quills. The quill need not reach all of the way over the apron as short workpieces do not usually need its support. This inability is of course a hallmark of a cheap machine, as you must be aware since you probably bought it for that reason.. So what's to complain about?

dockrat
11-07-2009, 11:25 PM
Btw dockrat, Why do you need a center on such short parts?

No, that was just posed to show how short the "quill" is trying to reach over the table. When I am using it with a long piece of stock I can reach the stock but can't get the carriage back far enough to start a cut without it hitting the tailstock hence the extention. Take another look at the second pic in the OP. The tailstock is up against the carriage and the ram is fully extended. Look where the cutting tool is. I could roll the compound back to start the cut but that then puts the front of the carriage in jeapardy of getting hit by the chuck if I am turning a larger piece of stock. Ask me how I know.

dp
11-07-2009, 11:42 PM
No, that was just posed to show how short the "quill" is trying to reach over the table. When I am using it with a long piece of stock I can reach the stock but can't get the carriage back far enough to start a cut without it hitting the tailstock hence the extention.

I have the same problem and is why I didn't use a center when turning this screw-making project: http://metalworkingathome.com/?p=40

Just too crowded.

dp
11-07-2009, 11:46 PM
Tailstocks do not have rams, unless they are also shepherds and have a male sheep.

Quill, barrel, and ram are common terms and I doubt anyone is confused.

oldtiffie
11-08-2009, 02:38 AM
I've taken a few pics of mine that might help.

I will post them later - after I have edited and up-loaded them.

Dr. Rob
11-08-2009, 03:31 AM
...Why do you need a center on such short parts?


... The quill need not reach all of the way over the apron as short workpieces do not usually need its support... So what's to complain about?

True perhaps, but clamping blank discs, drilling / tapping small jobs and faceplate work all ask you to reach a little further.

.

EVguru
11-08-2009, 04:13 AM
This is a problem to some extent on most Lathes.

Someone (Dave Piddinton?) came up with the idea of an extended tool holder to fit the Dickson toolpost and you can now buy such a thing direct from Myford. Copies are also available like this T1 size holder from Chronos

http://www.chronos.ltd.uk/acatalog/EXHML.jpg

It would seem to me that this is the most rigid (for the least work) solution for tailstick interference.

Doc Nickel
11-08-2009, 05:45 AM
I'm ahead of my time. :D

Back in 2004 I mentioned something very similar: here (http://bbs.homeshopmachinist.net/showpost.php?p=91543&postcount=11) I pondered making a shaper-ram style tailstock with a capstan wheel for drilling, here (http://bbs.homeshopmachinist.net/showthread.php?t=4707) I asked about the possibility of fitting a sort of "gib" to the quill, and I mentioned both again here (http://bbs.homeshopmachinist.net/showthread.php?t=9195) after replacing the handwheel screw in my Logan tailstock.

Since then I've revisited both ideas a couple of times, but only in passing. I'd still love to have a drill-press-quill style tailstock with a spider wheel rather than a handwheel.

I once even ran across a junked import drill press for cheap or free, and I recalled someone's post here where they sawed up a cheap import press to make a sort of toolpost grinder. I figured I could use the quill, handles and gear for the tailstock, but I hesitated and the guy threw it away.

And, one of the ideas I toyed with for the local art troupe to cast for me in iron was a new tailstock body- my Sheldon TS quill falls off the screw at exactly 2-1/2", with half an inch taken up by the tang of the tool, giving me an effective working range of two inches- really only about 1-3/4" to be sure it doesn't pop off the threads. More than a few times that just hasn't been enough.

One of these days I might even get around to trying one of 'em. :D

Doc.

Bguns
11-08-2009, 05:56 AM
People have skirted a simple idea...

A tailstock Quill,Ram, whatever..

Mounted in a set of 5C collets (for example) facing out from both ends of tailstock. One end (I would use outer, would have a simple closer wheel)

One of the 5C's would have reverse threads...

Outboard of that, is a thrust shoulder that can be involute splined for centering/antirotation effect, but still loose enough to allow the 5C's to center both ends... Square 5C's could be used for cheaper lathes :)

Would make for a longer tailstock top, but accuracy should be there...

Another handwheel used to run quill in and out...

Could even be CNC controlled...
With ram having no inner side key to let debris in, a seal could be used on inner side.

Worn ram/quill, either new ram or a regrind and new collets...
Back to my beer :)

John Stevenson
11-08-2009, 06:15 AM
Could be long, get a coffee and may run into two posts because of the pictures.

Actually this is a pet peeve of mine beside the crap Bridgeport and I have done a lot of study on it.

First the traditional design has just been copied over and over again, see my other post on tailstock's but there have been alterations. One was the CAV [ not to be confused with the 10EE clone the CVA ]

http://www.lathes.co.uk/wade%20cva/img13.gif

A quite cheap in it's day lathe but it did address the issue.

Possibly one of the better thought out designs was the French Cazeneuve which has lever, hand wheel, fine feed and power feed.

http://www.lathes.co.uk/cazeneuve/img4.gif

A very modern design with little of the grandfathers rights design.

But to get back to the OP question. The problem lies in the fact that the body is short therefore the barrel is also short, add to that the internal crew arrangement that is designed to be self extracting gives a travel that is in proportion to the body length and can't be altered.

Two obvious ways this can be addressed, the easiest way is to turn the barrel arrangement from an internal screw to external screw.
Not new, Myford's did this to address the same issues on the ML7, in fact when they brought out the new Super 7 they had to fit a longer tailstock to get anywhere near the same travel which reduced the between centres distance of the lathe.

http://www.lathes.co.uk/myford-ml7/img0.gif

7" swing and 20" between centres, because it has no self extracting facility, the barrel is hollow and you use a brass knock out bar, but it has a far greater travel than if it had an internal screw. The handwheel is retained by a keep plate fitted into the large diameter casting on the handwheel end.

This handwheel can be removed and a simple lever feed fitted instead very easily.

http://www.lathes.co.uk/myford/img18.gif

No alterations have to be done to fit this, it's a pure bolt on solution. The clamp that bolts onto the barrel clamps directly to the top of the square threads for ease of manufacture.
These work very well and I used one for years.

Continued on post two due to the 4 picture limit.

.

Bguns
11-08-2009, 06:17 AM
Guess I have to add.. a lever and handwheel, would work for my idea also :)
For lever feed with handwheel adjustable friction control quill/ram lock...

Loosen 5C's, run feed wheel off, slide new lever quill/ram in..

With spline selfcentering, and wear adjustment built in.. :)

Hollow center knock out if desired.. Or even a 3rd wheel for that ....

Not a cheap way to go.. But classy :)

oldtiffie
11-08-2009, 06:22 AM
Sorry - posted to wrong thread - deleted

John Stevenson
11-08-2009, 06:40 AM
When Myfords brought the Super 7 out [ S7 ] they tidied the design up and mage the tailstock similar to what was then the industry standard.

http://www.lathes.co.uk/myford/img8.gif

However this reduced the between centres distance by 1" not the extra length to carry the longer barrel and screw for the designed travel.

This body length / barrel length is critical if you use an internal screw.
They also offered a lever feed conversion.

http://www.lathes.co.uk/myford/img17.gif

However this was expensive as it needed a new longer barrel to achieve the same travel as the screw tailstock but unfortunately it didn't achieve this.

It is possible to get both lever feed and handwheel, AND retain the original barrel and screw IF you study the design correctly.

http://www.stevenson-engineers.co.uk/files/myford_leverfeed1.jpg

This is a S7 tailstock, ignore the coachwork as it's a working concept design and I'm not wasting money on new tailstocks.

Lever feed and handwheel using all the original components, no alterations to castings or any parts. Besides the lever components there is a barrel extension and a screw extension fitted internally, that is all.

Using just the lever feed the stroke is nearly 4", about 3/4" greater than the Myford lever design.

http://www.stevenson-engineers.co.uk/files/myford_leverfeed3.jpg

However the use of lever and fine feed via the handwheel can be used in any combination, just lever, just handwheel or handwheel in and quick retract with the lever to clear chips, in fact any combination you want.

New post.

Bguns
11-08-2009, 06:45 AM
Nice upgrade John..

The Myford at least, had a decent length of tailstock bore...

Saw a lever that kinda looked like that recently, from some Canadian :)

John Stevenson
11-08-2009, 06:51 AM
Using the lever and handwheel adds the original screw travel to the setup.

http://www.stevenson-engineers.co.uk/files/myford_leverfeed4.jpg


Once the screw is right in the handwheel can then be deployed.

http://www.stevenson-engineers.co.uk/files/myford_leverfeed5.jpg

In this case giving a massive 6" of travel but with the barrel / barrel extension fully supported. Chances are you would not use this travel but it's nice to know it's there if need for say deep hole drilling.

The Chinese ones can be done exactly the same way and I have one here but because of a conflict of interests I can't post those pictures.

One problem that still exists is the play in the barrel that I addressed in my other post on tailstocks and by designing a new keyway system that can also be rectified.
I have also come up with a sealing system that will double up to reduce wear and play but again that I can't mention but there are many many ways to achieve the same aims.

End of post.

.

Bguns
11-08-2009, 06:58 AM
That is pushing the length to diameter stiffness ratio, just a tad :)

But the travel is welcome in many applications...

My old SB with a wrench operated tailstock to bed clamp, and short quill travel... has eaten up a few hours of deep hole drilling time..

My bigger lathe has not limited me much yet... but will someday..

J Tiers
11-08-2009, 09:28 AM
Btw dockrat, Why do you need a center on such short parts?


The quill need not reach all of the way over the apron as short workpieces do not usually need its support. This inability is of course a hallmark of a cheap machine, as you must be aware since you probably bought it for that reason.. So what's to complain about?

Aside from the un-called-for slam against the OP in the second quote, you guys aren't thinking outside the box here.

Not ONLY does teh carriage/crosslide need to FIT under the tailstock ram, it would be nice if the carriage was actually USEFUL under there.... instead of just sitting there looking pretty. That means you want to have some carriage travel.

And then also you might someday want to actually turn a feature on the part which is close to the tailstock end. You may not have much travel towards the headstock either.

In the picture of the short ram, the carriage is not movable closer to the tailstock, so unless you can use the topside as a substitute workaround for longitudinal movement, you can't do the job that way.

If you happen to be turning a taper on part of the work, and straight portions on the rest, you might be doing a lot of taking off, resetting, putting back and continuing work. With a sensible tailstock-to-crosslide width ratio, that would not be necessary.

Or in some cases the topslide feed handles may graze or interfere with the tailstock when trying to get the topslide parallel to the axis for use as a substitute workaround feed.

That all-purpose wide crosslide was probably designed for milling, but causes some severe compromises.

On lathes designed for lathe work, without extra features, the carriage is purposely made narrow in the middle, specifically so that you WILL be able to actually use the carriage feed when working on small parts between centers. it also means that a sensible tailstock ram travel can be used and be quite functional.


Finally, length is relative.

if your part is 1.5" long, but 0.156 diameter or maybe smaller in places, you can't really expect to stick it out of the chuck and do work. You are going to use centers.


It sounds like J Tiers is describing a bed turret, see the second picture from the bottom. http://www.lathes.co.uk/hardinge/page4.html


Not really, I have a bed turret, they are totally different animals. but the design approach would work OK.

tdmidget
11-08-2009, 02:57 PM
Quill, barrel, and ram are common terms and I doubt anyone is confused.
There are a lot of "common" terms". Being "common" does not make it correct or acceptable.It could be that one of the differences between a HSM and a professional is knowing the terminology.

tdmidget
11-08-2009, 03:24 PM
J Tiers, the OP refers to the machine as a "Chi com BVB25L" and a "POS".
He knows what he bought. The question is "Why?". Even a chi com POS is a sizeable investment so why did he buy it if it is so bad?
However I'm not sure I see the problem here. Why not travel the saddle under the chuck? If it won't fit, get a smaller chuck. Any lathe can be fitted with a chuck so large that it impedes the cross slide travel.

dp
11-08-2009, 04:16 PM
There are a lot of "common" terms". Being "common" does not make it correct or acceptable.It could be that one of the differences between a HSM and a professional is knowing the terminology.

Or it could mean something else, entirely.

dockrat
11-08-2009, 04:23 PM
J Tiers, the OP refers to the machine as a "Chi com BVB25L" and a "POS".
He knows what he bought. The question is "Why?". Even a chi com POS is a sizeable investment so why did he buy it if it is so bad?
However I'm not sure I see the problem here. Why not travel the saddle under the chuck? If it won't fit, get a smaller chuck. Any lathe can be fitted with a chuck so large that it impedes the cross slide travel.

Tdmidget, if you refer back to my original post you will see where I said “As a hobby lathe it is adequate except for the tailstock.” The POS that I was referring to was the tailstock design only. From what I read in the posts in this thread, my cheap Chinese lathe isn’t the only one with this problem. As to why I bought it….at the time I had absolutely no knowledge concerning lathes. It was more a case of what I could fit in the available room. This fit and I have used it to do a lot of stuff and so far I have not had any case where I have not been able to find a work around to overcome its failings. On reading through your posts I can tell that you know everything there is to know about machines and machining so instead of slamming us HSM’ers for our terminology and cheap machines, how about adding some positive input to the question at hand?

Timleech
11-08-2009, 04:33 PM
http://i559.photobucket.com/albums/ss38/Timleech_2009/DSCF2771.jpg

A full 11" of quill travel.
OK it's a 19" lathe. but I do have to watch out for compound and tailstock interfering with one another...

Tim

S_J_H
11-08-2009, 08:42 PM
Well most of the small import lathes just have not been given much design thought period. Everything is boxy and square. The problem is not really the tailstock. The entire saddle/tailstock relationship is just poorly though out. This effects many of the import machines and not just yours.
The saddles on the these machines also do not have long enough "wings", for the lack of a better term. The saddle wings give the saddle much extra bed contact, making for a more solid foundation. Having long saddle wings allows for a narrower cross slide which improves tail stock reach.

Also the QCTP's usually reduce tailstock reach as the tool is mounted off to the side which results in the need to move the carriage more to the right.

My SB9-
http://i109.photobucket.com/albums/n48/S_J_H/SOUTHBEND%209/IMG_1652.jpg
http://i109.photobucket.com/albums/n48/S_J_H/SOUTHBEND%209/IMG_1651.jpg

My Artisan 11x24-
This machine I love. Note the unusual saddle. It has 3 saddle wings due to it's unusual bed ways and excellent tailstock reach. The tailstock slides over the center wing.
http://i109.photobucket.com/albums/n48/S_J_H/SOUTHBEND%209/IMG_1654.jpg
http://i109.photobucket.com/albums/n48/S_J_H/SOUTHBEND%209/IMG_1641.jpg

Steve

S_J_H
11-08-2009, 09:04 PM
ahhh, I see that the BV25 lathe is also sold as a combo machine. That might explain the wide saddle and cross slide. The extra wide cross slide would surely come in handy for milling.

Steve

J Tiers
11-08-2009, 09:24 PM
ahhh, I see that the BV25 lathe is also sold as a combo machine. That might explain the wide saddle and cross slide. The extra wide cross slide would surely come in handy for milling.

Steve

At first I thought it WAS a 3 in 1 machine.

Black_Moons
11-08-2009, 09:58 PM
Maybe an idea for a group project would be a range of tailstock castings we could buy and then do with what we wish (since we all have our own ideas, just a big block of iron that looks like a tailstock body would likey be best, can bore or dovetail or whatnot ourselfs)

I don't exactly wanna modify my existing tailstock to be longer because as is I allready had to take the handle off the handwheel because it limits my bed length as my tailstock hits the wall before it hits the end of the bed :P (Small workshop)
But an second extra long/rigid tailstock would be swapable.

My lathe for example just uses the single prismatic way and flat way for the tailstock, so milling it for alignment/fit should be easy..

johnnyd
11-08-2009, 11:39 PM
You might present this problem to Craig Donges over on the PM forum. He's doing some casting work(having it done)
Maybe he could do a "series" of castings that would cover a range of lathe sizes that you could order by "length"?

tdmidget
11-09-2009, 03:49 PM
Dockrat, pull your panties out of your crack and read my post. If you fit a smaller chuck the saddle can pass under it and your tailstock will be closer.

dockrat
11-09-2009, 04:28 PM
Dockrat, pull your panties out of your crack and read my post. If you fit a smaller chuck the saddle can pass under it and your tailstock will be closer.

A smaller chuck isn't going to help me if I am trying to turn 7" OD stock. I can barely hold it with the 5" chuck I have with the jaws sticking out far enough to cause a major crash against the saddle if I ain't paying attention. However even with normal turning where I can get under chuck with the saddle, I can't get back far enough to start a cut as the backside of the saddle is against the tailstock. Hence the need for the adaptor. Here, lemme show you. I just went and took a picture. Note that the "quill" is at full extention, the compound is as far out as it will go without the screw dropping out, but I can't get back far enough to start a cut as the saddle is up hard against the tailstock and ya can see where the cutter is.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1334Medium.jpg

John Stevenson
11-09-2009, 04:39 PM
How about remounting to top slide further back?
Don't know how much of a job that is as we can't see how it pivots underneath.

.

tdmidget
11-09-2009, 04:44 PM
Well I think someone already mentioned this but have you disassembled the quill to make sure that you have no more travel? There appears to be plenty of length there. A malfunction keeping you from full travel perhaps? Do you have the specs for the machine? What does it say for quill extension?

dockrat
11-09-2009, 04:53 PM
How about remounting to top slide further back?
Don't know how much of a job that is as we can't see how it pivots underneath.

Like this John.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1337Medium.jpg

I don't think that moving the topslide would be an option. I get by fine with the extention. I just have to make sure I start a drill hole with a spotting drill otherwise it wanders a bit with the deflection. Actually it kinda acts like a wiggler when I am fine tuning a center position in my 4 jaw.:D

Timleech
11-09-2009, 05:48 PM
I don't think that moving the topslide would be an option. I get by fine with the extention. I just have to make sure I start a drill hole with a spotting drill otherwise it wanders a bit with the deflection. Actually it kinda acts like a wiggler when I am fine tuning a center position in my 4 jaw.:D

How about a drill chuck holder for your QCTP? You could mark the cross slide with a 'centre' position, or even arrange an indexing peg.

Tim

dockrat
11-09-2009, 05:52 PM
Tim....thats an option worth exploring as long as it could done accurately

John Stevenson
11-09-2009, 05:58 PM
Or even making a dummy tailstock that bolts to the end of the cross slide if you can wind it back far enough to be useful but stay out of the way when the tool is cutting.
taper pin drilled and reamed thru the top slide so it always drops onto centre when needed.

Also allows power feed drilling from a known centre reference, problem with using tool posts is that they may not be square to the lathe axis, rely on top slide position etc

.

Timleech
11-09-2009, 06:22 PM
Or even making a dummy tailstock that bolts to the end of the cross slide if you can wind it back far enough to be useful but stay out of the way when the tool is cutting.
taper pin drilled and reamed thru the top slide so it always drops onto centre when needed.

Also allows power feed drilling from a known centre reference, problem with using tool posts is that they may not be square to the lathe axis, rely on top slide position etc

.

If you look at my pic 'showing off' the quill travel on my lathe, in the background is the 'power drilling attachment' which is the same sort of idea. That one clamps into a Vee groove on either side of the cross slide, which allows it to be pushed well out of the way when not needed. Even without that facility it could be useful to you if there's enough cross slide travel.
Indexing on mine is dead simple, there's a small block screwed to the underside, you wind it back on the cross slide until that block sits against a matching block on the saddle. I'll do a pic tomorrow if you wish, if my explanation isn't clear.

Tim

dockrat
11-09-2009, 06:30 PM
tim pics are always good :)

oldtiffie
11-09-2009, 08:47 PM
ahhh, I see that the BV25 lathe is also sold as a combo machine. That might explain the wide saddle and cross slide. The extra wide cross slide would surely come in handy for milling.

Steve

You are dead right Steve.

As the OP said, it is the same as my lathe - except that I bought it as a very good "3-in-1" machine. I junked the really good "round column" mill attachment as I have 3 other mills (1 x Sieg X3, 1 x Sieg Super X3 and a HF-45 - all vertical dove-tail column mills). The large flat - and very handy big flat top on the cross-slide is to take a very good tee-slotted de-mountable work table:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Part_off1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathe1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/AirSmith09.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/AirSmith06.jpg

It is a very good lathe - very solid and accurate -but does not have a power feed nor a quick-change feed/screw-cutting gear-box but that does not concern me at all.

I have a few pics and comments to add to this thread as soon as I get the pics edited and up-loaded - hopefully in the next day or so.

TexasTurnado
11-09-2009, 09:34 PM
Why not just build a new tailstock using the base from the present one?

http://i288.photobucket.com/albums/ll168/TexasTurnado/Photo25-P1010114.jpg

This allows you to up a size in MT taper, if desired, and more quill travel. :)

Then trash that puny headstock and replace it with a spindle with decent thru bore and non-threaded mounting so you can turn in reverse without worrying about the chuck coming loose. :D

http://i288.photobucket.com/albums/ll168/TexasTurnado/Photo24-P1010112a.jpg

BadDog
11-09-2009, 09:47 PM
Or just save the hassle and buy a bigger lathe to get on with making stuff besides tools. ;) Which reminds me, I've got a 1.5" tie rod awaiting my attention. It will need that spindle bore I purchased to easily cut, face and thread both ends...

oldtiffie
11-09-2009, 10:29 PM
Why not just build a new tailstock using the base from the present one?

http://i288.photobucket.com/albums/ll168/TexasTurnado/Photo25-P1010114.jpg

This allows you to up a size in MT taper, if desired, and more quill travel. :)

Then trash that puny headstock and replace it with a spindle with decent thru bore and non-threaded mounting so you can turn in reverse without worrying about the chuck coming loose. :D

http://i288.photobucket.com/albums/ll168/TexasTurnado/Photo24-P1010112a.jpg

That's one helluva nice job TT. How well does it work?

dockrat
11-09-2009, 10:56 PM
That's one helluva nice job TT. How well does it work?

No kidding!!! It impressed the hell out of me too.

TexasTurnado
11-09-2009, 11:03 PM
Or just save the hassle and buy a bigger lathe to get on with making stuff besides tools. ;) Which reminds me, I've got a 1.5" tie rod awaiting my attention. It will need that spindle bore I purchased to easily cut, face and thread both ends...

What? And miss all the fun and challenges of precision tool making? Nah, loved every minute of it..... :) This conversion will even handle your 1.5" tie rod job - bore is 1 5/8. :D

BadDog
11-09-2009, 11:55 PM
What? And miss all the fun and challenges of precision tool making? Nah, loved every minute of it..... :) This conversion will even handle your 1.5" tie rod job - bore is 1 5/8. :D
Hehe, even though your skill clearly eclipses my own, I do know what you mean. I've enjoyed tool making, rebuilding, AND using since I caught the bug.

Very nice indeed...

oldtiffie
11-10-2009, 07:48 AM
For those that may have forgotten - or side-tracked themselves - or perhaps inadvertently tried to divert or hi-jack the thread (again?), the OP is here:

Tailstocks seem to be the topic today so in keeping with that, here is my tailstock rant. My lathe is a chicom BVB25L (Tiffie, it’s the same as yours) As a hobby lathe it is adequate except for the tailstock. Whoever designed it for this lathe should have it tied to an ankle just before he goes for a swim. The saddle on this lathe is so wide that the tailstock will not reach across it . In order to use the tailstock I have had to add an mt2 to mt2 adaptor. So although I get no rotational deflection I do get lateral deflection. A few pictures to show you what I mean.

Here is the tailstock right up against the saddle with the ram retracted:

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1327Medium.jpg

And again with the ram at full extension:

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1330Medium.jpg

The ram with the adaptor. Way too unsupported, hence the deflection.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1331Medium.jpg

What a POS eh? One day when I feel capable to do so, I am going to bite the bullet and cut off the top of that tailstock and try to make something better. John, Brian, Anyone??? Have you got a good design???


For Dockrat (Ernie)

To recap - here are the previous links to my lathe - wide flat face on the top of the cross-slide and all:

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Part_off1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathe1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/AirSmith09.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/AirSmith06.jpg

Now to move on-wards:

This is how mine is and some of the things I've done or considered with my lathe - which as you say - is similar to yours.

Rather than be limited to just addressing the tail-stock I decided to just address drilling holes in the lathe as well as turning small lengths and see where I went or got to from there.

Here are some comments and links to my pics. There are a lot of pics and at a maximum of four images a post it would be a real PITA - especially for those with slower connection.

So bear with me.

Here is my lathe in the situation you are concerned about. I have no problems here.

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock2.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock3.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock4.jpg

I bought a "Quick Step Mill" from UK for my lathe as I intend to try it out with thread milling - with it set over for the thread helix angle and not. It is mounted in my lathe tool-post but could be mounted on my cross-slide as well. It has ER-20 collets and 90 speeds and lots of "grunt" for a small-ish machine and motor. I bought it for thread milling as it can be tilted for the thread helix angle etc. etc. It has the capacity to do a lot of drilling work that I may otherwise have to use my tail-stock for/with.

Cross drilling:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock5.jpg

Doing the tail-stock drilling"
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock6.jpg

Tilted as for thread milling:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock7.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock8.jpg

The belt (3 speeds) and gear-box gear change (3) = 3 x 3 = 9 speeds:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock9.jpg

Gear shift (3 positions):
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock10.jpg

ER-20 collets (1>13mm in 1 mm steps):
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock11.jpg

The tilting "quadrant" (plate) - held in lathe tool-post:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock12.jpg

Other views:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock13.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock14.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock15.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock16.jpg

I thought of modifying or adapting my "John Stevenson Special" spindexer with its C5>ER-32 collet adaptor as well (bought from Arc Eurotrade (UK). There is no reason that this won't work as it could act in place of the tail-stock as the collets will handle anything from 2mm (~0.080") to 20mm (~0.800"). In this use there is no need for the tail-stock as I can feed the drills etc with my lathe carriage - as long as the lathe bed will allow:

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock17.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock18.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock19.jpg

An over-view of my lathe:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock20.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathetail-stock21.jpg

As the Quick Step Mill has an excellent ER-20 collet system and a very good spindle as well as a top speed of 4,000RPM (no "typo") it will also works pretty well as a tool-post grinder as well.

I hope this helps.

TexasTurnado
11-10-2009, 11:26 AM
That's one helluva nice job TT. How well does it work?

Thanks for the kind comments. :o It works very well indeed - there was some concern originally about vibration because I used steel instead of cast iron, but I have not found the steel to be a problem. Maybe it's because the cast iron bed dampens any vibration, or maybe it's just because it is so much stiffer than the original...

dockrat
11-10-2009, 11:55 AM
Tiifie, thanks for your input. You have done some neat mods on that lathe!! I am quite happy with mine also except for the one issue with the tail stock that you didn't address. That is the issue of trying to start a cut when the carriage is up against the tailstock. I am sure yours is the same and I wonder how you overcome this. On mine I would need almost one more inch of quill extention. See the following pic.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1334Medium.jpg

Note that the quill is at full extension, the compound is back as far as it will go, and the saddle is right up agains the TS. Now look where the cutter is. I would need to move that cutter back another 3/4" in order to start a cut. Hence my rant:D

Timleech
11-10-2009, 02:41 PM
Here are a couple of pics of my power drilling attachment, something along these lines might help with some of dockrat's problems but not the one of starting a cut from a centre. A LH tool would help there, but might mean changing tools partway through a cut. Can the QC post be turned to any angle? if so, that can sometimes help with tight situations.


http://i559.photobucket.com/albums/ss38/Timleech_2009/DSCF2774.jpg

The cross slide has a vee groove in either edge, this serves as a dovetail for locating & clamping the bracket.
The bracket is parallel bored, with a screwed cotter clamp. The sleeve is an old tailstock quill, turned down to fit. The lathe makers supplied an MT holder with ejecting screw, that was missing when I got the lathe and a new one is silly money. I find the drift ejection serves perfectly well.
The parallel bore is also handy for holding die boxes etc., using simple split reducing sleeves.

This one shows the indexing stop:-

http://i559.photobucket.com/albums/ss38/Timleech_2009/DSCF2776.jpg

You just clamp the bracket to the cross slide, somewhere near, then wind out the slide until the two blocks make contact.

Tim

small.planes
11-10-2009, 04:21 PM
Not ideal if you need to turn upto a 90 shoulder, but why dont you twist the toolpost to the right?

Dave

oldtiffie
11-10-2009, 04:48 PM
Ernie.

My reply would have been the same as Tim's.

Rotate the tool-post right/clock-wise which will move the point of the tool right as well and will get your cut started.

Try using the tool in the tool-holder on the front of the tool-post.

If you have to re-start/"pick-up" the job and use several cuts along its length - well that's normal and just the way it is. You should be able to do that within "tenths".

That sort of "stop - move back - re-start" a cut is the classic way of countering a taper in a lathe.

Its not the "journey" - the way you do a job or how you get there - that counts, but the "arrival" - how the job finishes - that does count.

If I have time today, I will "dummy" your set up, take a few pics and post them.

There is no reason why you can't use or modify Tim's set-up and mount a centre on an adaptor on your cross-slide, lock the cross-slide and saddle and use your top-slide/compound-slide to turn the job (set it at zero). Depth of cut can be regulated by clamping the tool-post (not too tight!!) and "tapping" it to rotate the tool-post slightly on the top-compound slide to vary the depth of cut. It seems a bit "Heath Robinson" but with a bit of care and patience (and luck?) - it works.

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

http://images.google.com.au/images?hl=en&q=heath+robinson+%2B+images&um=1&ie=UTF-8&ei=B975StSWMNOGkQXEw9CoCw&sa=X&oi=image_result_group&ct=title&resnum=1&ved=0CBQQsAQwAA

http://www.google.com.au/search?hl=en&q=heath+robinson+%2B+images&btnG=Search&meta=&aq=f&oq=

dockrat
11-10-2009, 05:22 PM
Tiff-Dave you guys are right. There are many work arounds and I have used them all to get the job done in spite of the short tailstock but your all missing the point of my rant here. I wasn't whinning because I couldn't get the job done. I was whining because why couldn't they design a tailstock with one inch longer reach so we wouldn't have to jump through all these hoops to get the job done. I think I am starting to sound like my wife here. "All I want is one more inch" :D

Alistair Hosie
11-10-2009, 05:23 PM
As always Tiffe I am impressed with your work. Also texas tornado nice job on the headstock and tailstock too.I would have been temted either like Evan (since you have the skill) to make a lathe from scratch. also Johns device using an existing 5 c collet to take on a new life of it's own I have one of his for using 5c collet chuck which I have with a D1-4 camlock now I can use E R 32 collets in it too you guys keep me and everyone else here young.:D Alistair

BadDog
11-10-2009, 05:32 PM
How about turn the compound and slide the tool post over closer to the TS end? Still square to cut to a shoulder, and as long as the compound doesn't foul the chuck, should give you back full range. Or is that one of those with the stud and no adjustment? Even then, you could kick the compound a bit past 90* to the other side and then extend it flush with the end to get that last little bit closer to the TS.

lynnl
11-10-2009, 06:00 PM
There are a lot of "common" terms". Being "common" does not make it correct or acceptable.It could be that one of the differences between a HSM and a professional is knowing the terminology.

Or it could be that someone is just determined to try to force useage of the one term he knows.

My LeBlond manual describes it as the 'spindle'.
This link shows it as 'barrel' or 'spindle' or 'ram' or 'shoot', tho the picture just shows the first two terms:
http://www.lathes.co.uk/latheparts/index.html

This link (referring to Southbends) uses the term 'spindle' (see part no. 201)
http://www.strippingknives.com/email/Lathe/lathe_partlist.htm

"Quill" to me describes a housing through which a rotating spindle runs, e.g. a Bridgeport mill quill or a drill press quill.

oldtiffie
11-10-2009, 06:26 PM
Tiff-Dave you guys are right. There are many work arounds and I have used them all to get the job done in spite of the short tailstock but your all missing the point of my rant here. I wasn't whinning because I couldn't get the job done. I was whining because why couldn't they design a tailstock with one inch longer reach so we wouldn't have to jump through all these hoops to get the job done. I think I am starting to sound like my wife here. "All I want is one more inch" :D


Thanks Ernie.

Impo(r?)tent things first.

Was that "one more inch" meant to be longer, diameter or circumference? My problem was not so much getting it in as keeping it in. Sometimes it was or like a clapper in a bell.

Now that we have got back to basics and have addressed the really important (impotent??) issues - let's get back to the lathe.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1334Medium.jpg

When I first used a lathe in my pre-apprenticeship Trade/Technical School days - age 11 - 61 years ago - we used the classic "lantern" type tool-post - which did the job nicely - just as it will on your job. The "lantern" TPH held the tool on the axis of rotation of the tool post on the top-slide.

http://img.photobucket.com/albums/v11/horteniv/DSC06377.jpg

http://www.practicalmachinist.com/vb/showpost.php?p=1115038&postcount=13

http://www.google.com.au/search?hl=en&source=hp&q=lantern+tool+post&btnG=Google+Search&meta=&aq=f&oq=

dockrat
11-10-2009, 07:40 PM
http://www.practicalmachinist.com/vb/showpost.php?p=1115038&postcount=13

LOL ya had me laughing with that link!!! What a great response!!! Another 1/2" would have done it. Too funny

oldtiffie
11-10-2009, 08:11 PM
Glad to help Ernie.

I do hope you didn't "end up" (and succeed in??) laughing your cock off!!!

tdmidget
11-11-2009, 05:14 AM
Hmmmm What is wrong with Baddog'sdea? I too wondered why tthe compound is parallel to the z axis. Turn it 90 degrees and slide the QC where you need it.

jackary
11-11-2009, 06:24 AM
I know I'm a late contributor to this thread its because I have been having problems downloading this website has is been going wrong or is it my computer? Anyway here is my way or getting the topslide close to the tailstock with minimum overhang and a long 5" tailstock travel. Obviously a bit to drastic a mod for a normal lathe but it works well.
Alan
http://i107.photobucket.com/albums/m287/jackary2003/P1010375.jpg
http://i107.photobucket.com/albums/m287/jackary2003/P1010376.jpg
http://i107.photobucket.com/albums/m287/jackary2003/P1010377.jpg

oldtiffie
11-11-2009, 07:07 AM
Jackary.

That is a brilliant job - from concept, planning and execution.

I never get tired of seeing it - ever!!

Can you please post the link to it in full - you posted it some time ago. There will/may be some here who have not seen it to appreciate it.

As regards your problems with accessing this site/forum - can you please explain/detail what the problems are or seem to be please?

I expect that there may well be some others here with similar problems.

There will also be some here who can identify the cause, the effects and the solution.

EVguru
11-11-2009, 07:22 AM
I was trying to remember a solution I'd seen to the tailstock problem I'd seen and Jackary's post prompted my memory.

http://www.lathes.co.uk/metalmaster/img0.gif


http://www.lathes.co.uk/metalmaster/index.html

Black_Moons
11-11-2009, 07:33 AM
hhaha at some of the other design choices on that.. Lets move the entire bed up/down to work height while milling, No compermising the lathe design there!
Im sure keeping that bed within an arc second of alignment is fun :P

Here I thought I had seen it all, but now iv seen the round collumn lathe/3in1 im sure I have.

small.planes
11-11-2009, 07:42 AM
Tiff-Dave you guys are right. There are many work arounds and I have used them all to get the job done in spite of the short tailstock but your all missing the point of my rant here. I wasn't whinning because I couldn't get the job done. I was whining because why couldn't they design a tailstock with one inch longer reach so we wouldn't have to jump through all these hoops to get the job done. I think I am starting to sound like my wife here. "All I want is one more inch" :D
Yeap, I think I missed that....
Mind you the solution is simple:
Go get a piece of HRS, Use lathe, Make 1" longer tailstock barrel :p
You could probably have done it by now ;)

Dave

Black_Moons
11-11-2009, 08:15 AM
Or buy a live center that sticks out an inch longer then most, some even have a fine taper after the point to give extra space for the tooling/toolpost.

One of those replaceable point centers, you could make a new point for.. http://www.lathemaster.com/images/TN_LIVE_CENTER_SET_-_MT2.JPG

lazlo
11-11-2009, 09:03 AM
Jackary.

That is a brilliant job - from concept, planning and execution.

I never get tired of seeing it - ever!!

Tiff, if you get Model Engineering Workshop, they have a 2-part series about Alan's lathe.

As EVGuru noticed, it's a high-tech version of the Metalmaster.

dockrat
11-11-2009, 11:46 AM
Tdmidget….been there, done that.

Black moons. Got one of those and have made quite a few different points for it.

Small.planes. that’s what’s going to happen.

But you are all still missing the point of my rant which is why would they not design the tailstock to fit the saddle?

jackary
11-11-2009, 04:20 PM
Old Tiffie wrote
Can you please post the link to it in full - you posted it some time ago. There will/may be some here who have not seen it to appreciate it.

As regards your problems with accessing this site/forum - can you please explain/detail what the problems are or seem to be please?

I expect that there may well be some others here with similar problems.

There will also be some here who can identify the cause, the effects and the solution

If you search " Stepperhead" on this forum or Google you will get some feedback. As to the computer problem it seems to have fixed itself after I asked the internet provider why was it so slow and threatened to change supplier. I may not be good at computers but how did it fix itself without any effort from my end apart from complaining? Any computer experts can give the reasons if they know the answers. Sorry to digress but the problem was that when I selected this group I got the reply that it could not be contacted and try again. Nothing I did or knew fixed it: it mended itself. The strange thing is that it only seemed to apply to this website so I thought I had been deselected. Paranoia rules.
Alan

dp
11-11-2009, 04:57 PM
I know I'm a late contributor to this thread

Thanks for popping in here. I'd been searching through all my stuff looking for a link to your pictures as I recalled you'd come up with a very elegant solution and a fine looking machine in the process.

lazlo
11-11-2009, 05:16 PM
Here's Alan (Jackary's) thread on the Stepperhead:

http://bbs.homeshopmachinist.net/showthread.php?t=32574