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Re: Unimat 3 mill headstock alignment problem

 

You don't need to clamp so hard that you deform the part. Just enough to hold the part firmly. If the part already has the slit, put slices of aluminum can metal in the slit to fill it, and clamp the slit closed.?

On any Unimat, you're going to take very light cuts. In inch measurements, 0.003" or less would be about right. It will take around 40-41 cuts to get close, 1/8th inch being about 3mm. Or? 0.125 decimal inches. Then take 0.001" cuts while testing the fit after each cut. Do not get in a hurry.?

Rather than buy the fittings, maybe you can find slices of aluminum? stock to make your own.? Your shop where you had the machinist work on the other part might be able to provide the material from off cuts. Those are pieces too small to clamp in their machines. And they can often be had cheaply. I'm all about cheap! ??

Stack them together to machine them, if the stack will fit your lathe. Step drill the holes as you've described. Then bore or ream to finished size, all still in the stack. Super glue, or cyanoacrylate, will hold a stack together, and can also hold a part to a faceplate for machining. The faceplate then used instead a chuck. Working individual parts makes it more likely they won't be a perfect match, but it might be necessary if you don't have enough room for the stacked parts.?

HTH!

Bill in OKC?

William R. Meyers, MSgt, USAF(Ret.)

Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better.
Expect in one hand, expectorate in the other. See which one gets full first.



On Thursday, December 5, 2024 at 06:55:30 AM CST, Julius Henry Marx via groups.io <sawbona@...> wrote:


Hello:
?
On Wed, Dec 4, 2024 at 11:45 PM, John Hutnick wrote:
... do not quite understand some of the comments ...
@John: Julius will do ...? 8^¡ã
?
I'm sorry, my command of the english language is rather limited.
Specially in technical matters.
... what I suggest.
... 3 or 4 of the original type shaft collars ...
I was on my way to doing exactly that when I realised that they were ?25 and the U3 column ?28.
... few dollars each one ...
... of little consequence.
In my case, the consequence depends on the total cost.
There are steep shipping charges and import taxes for me to pay.
A bad local currency/US$ exchange rate makes things worse.
... clamp the rounded end in your chuck, and bore to 28mm.
Clamp the rounded end securely enough to bore 25mm -> 28mm I will surely alter the original diameter.
ie: deforming it, like if I were clamping it around the ?25mm rod but without the rod.
The resulting ?28mm will be off center (and probably not round) with respect to the mounting holes.
?
I once had a similar clamp made for me at a shop.
The chap making the piece (an old timer kind enough to let me watch the process and explain) emphasised that the slit was the last thing to do.
... drill out the outside holes up to 10mm ...
Yes, that can most probably be done albeit with the proper precautions.
In small steps, I guess.
eg: 8.25 / 8.50 / 8.75 and so on or with a stepped drill from below (?).
... not satisfied ...
... throw out the pieces, nothing much lost.
I beg to differ, see above.
... then buy something else.
Or maybe look for a different solution, like my previous post?
You clearly have much more experience that I.
I'd appreciate your comments on it.
?
That said, in my opinion there is a reason for this problem not ever getting solved without great expense or complications.
eg: the severe limitations posed by Emco's quill holder / headstock adapter design and cost cutting measures.
?
The Heminway Kits, UPVLA (and maybe others) never gained much momentum.
Even with a high market price there was demand for them but in both cases a limited number were made.
It has proven all but impossible to find usable traces of them on the web. eg: flyers or instruction sheets.
?
Maybe they did not work as well as intended / advertised?
No idea, I have not seen reviews.
?
Thank you for your input.
?
Best,
?
JHM
Re: Unimat 3 mill headstock alignment problem

 

Have we got to the situation of all talk and no action?
I have posted previously the device that I made for the Unimat SL.
Since we are on the subject of the Unimat 3, can members please post photos of what they have made?? And not something that you could buy at one time in the past, no longer available, etc.
Regarding milling a keyway in the column, then making something in the head to align with it, etc.: for myself, I would not try this because I might screw it up.? As far as the local very cooperative machine shop that will do this for you economically, I do not think that we have these where I am.? Also, if I would try to do this, I want a spare column as back up.? I always want to be able to put something back to where it was.? There have been very few Unimat 3 spare columns on Ebay.
So if I wanted to do this for myself, I am back to making something with shaft collars.? The parts are not that expensive, and you can always take apart and revert to original.
Re: Unimat 3 mill headstock alignment problem

 

For full size round-column milling machines, the procedure shown in this video is quite adequate for quickly re-aligning the head after moving it in the z-axis.
?
?
Would a similar approach work in principle with the Unimat?.... recognizing that a smaller and slightly different variation of the apparatus might be required in order to fit between the head and milling table of the Unimat.
?
~Hans
Re: Unimat 3 mill headstock alignment problem

 

Hello:
?
On Thu, Dec 5, 2024 at 04:39 AM, Keith S. Angus wrote:
... limited to the U3 ...
It is.
For the older Unimats, John H. found an easy and clever solution with which he is satisfied.
... there is room in the casting for a keyway ...
I take it that you are referring to the headstock adapter.
ie: column clamp, to the left or right of the column?
... plenty of material in the column for a groove.
Yes, seems that there is.
... cut a groove and fit a key for the full length of the column ...
... tight fit on the key ...
Like the attached file?
... cut a keyway in the milling bracket ...
This part I don't understand.
?
I think the headstock adapter does not have enough material for this.
If I measured correctly, there is no more than 5.0mm to either side of the column.
... cutting the long keyway in the column is beyond a Unimat only workshop ...
Quite so.
But it does not have to be the whole length of the column.
?
Whether you are mounting the column on the U3 bed or the Unimat milling table, you can start at 100mm from the bottom end.
You could stop at 10mm from the top but you may not want to if you want an easy way to slide everything off.
Still, you need an accurate milling machine for that.
... rest could be done with hand tools and some care.
Provided you are properly acquainted with the assorted how to's.? 8^ )
... get my hands on a milling head.
... draw something up and see if I can make it work on paper.
I have mine and can measure it for you.
Let me know what you need.
?
Best,
?
JHM

groove_key.jpg

Re: Unimat 3 mill headstock alignment problem

 

Hello:
?
On Wed, Dec 4, 2024 at 11:45 PM, John Hutnick wrote:
... do not quite understand some of the comments ...
@John: Julius will do ...? 8^¡ã
?
I'm sorry, my command of the english language is rather limited.
Specially in technical matters.
... what I suggest.
... 3 or 4 of the original type shaft collars ...
I was on my way to doing exactly that when I realised that they were ?25 and the U3 column ?28.
... few dollars each one ...
... of little consequence.
In my case, the consequence depends on the total cost.
There are steep shipping charges and import taxes for me to pay.
A bad local currency/US$ exchange rate makes things worse.
... clamp the rounded end in your chuck, and bore to 28mm.
Clamp the rounded end securely enough to bore 25mm -> 28mm I will surely alter the original diameter.
ie: deforming it, like if I were clamping it around the ?25mm rod but without the rod.
The resulting ?28mm will be off center (and probably not round) with respect to the mounting holes.
?
I once had a similar clamp made for me at a shop.
The chap making the piece (an old timer kind enough to let me watch the process and explain) emphasised that the slit was the last thing to do.
... drill out the outside holes up to 10mm ...
Yes, that can most probably be done albeit with the proper precautions.
In small steps, I guess.
eg: 8.25 / 8.50 / 8.75 and so on or with a stepped drill from below (?).
... not satisfied ...
... throw out the pieces, nothing much lost.
I beg to differ, see above.
... then buy something else.
Or maybe look for a different solution, like my previous post?
You clearly have much more experience that I.
I'd appreciate your comments on it.
?
That said, in my opinion there is a reason for this problem not ever getting solved without great expense or complications.
eg: the severe limitations posed by Emco's quill holder / headstock adapter design and cost cutting measures.
?
The Heminway Kits, UPVLA (and maybe others) never gained much momentum.
Even with a high market price there was demand for them but in both cases a limited number were made.
It has proven all but impossible to find usable traces of them on the web. eg: flyers or instruction sheets.
?
Maybe they did not work as well as intended / advertised?
No idea, I have not seen reviews.
?
Thank you for your input.
?
Best,
?
JHM
Re: Unimat 3 mill headstock alignment problem

 

If the discussion is limited to the U3, there is room in the casting for a keyway, and plenty of material in the column for a groove. I would cut a groove and fit a key for the full length of the column, making it a tight fit on the key (I'm imagining about 6 mm square). Then cut a keyway in the milling bracket, wide enough to take a tapered gib strip which can be adjusted to take out the slack, or maybe set by a screw so it can be tightened when milling, and released for movement. I don't have a milling head for my U3, so I can't work it out in more detail. Obviously, cutting the long keyway in the column is beyond a Unimat only workshop, but the rest could be done with hand tools and some care.
?
I may be able to get my hands on a milling head. I so I'll draw something up and see if I can make it work on paper.
Re: Unimat 3 mill headstock alignment problem

 

For Mr. Marx and others, I simply do not quite understand some of the comments re the Uni 3 head.
So here is what I suggest.? Buy 3 or 4 of the original type shaft collars that we started this discussion with(the ones that the Chinese seller says are all no good).? The cost of a few dollars each one way or another is of little consequence.??
I measured the ones that I used on my Uni SL conversion.? There is enough room that you can clamp the rounded end in your chuck, and bore to 28mm.? If you are carefull. you can drill out the outside holes up to 10mm for a guide rod on one side and threaded on the other.? With 3 of these collars, you now have something that fits your Uni 3 column, and provides 10mm rods for rigidity.? Clamp the Uni 3 quill tight and use the threaded rod to move the head up and down.? If when you are done you are not satisfied, disassemble, throw out the pieces, nothing much lost.
Now somehow there always seem to be questions about the famous "rigidity".? What I have descibed is the best that I think that you can do.? If that does not suit, then buy something else.??
Unimat 3 mill headstock alignment problem

 

Hello:
?
It seems that solving the problem with the Unimat 3 (?28mm column) milling head cannot be solved as easily as with the older models (?25mm column)so I had another look at what I had seen on the web.
?
Most if not all the viable solutions I have come across rely on an external arrangement, be it with one or two rods to maintain the head aligned as it is moved up / down.
?
They all have the advantage of not having to alter the column or associated parts the possibility of additing a vertical screw for positioning the head.
?
On the other hand, the question of just how much rigidity such a system offers has been raised a few times, something that (depending on various factors) would make it unsuitable. I share that thought: not rigid? Not worth the trouble / expense.
?
Among notable solutions that have come and gone are the solution and the UPVLA solution recently brought up by Dick.
Then there is the only one I have found to be in the market but requires replacing the whole shebang with the exception of the quill holder.
?
Interesting approach but rather expensive. It can be had from the for a nice and tidy sum, which in my specific case would amount to ~US$350.00 and only because it is shipped from the UK and not the US which would make it a ludicrous proposition.
?
Evidently not an easy matter to solve post market without having to put up an interesting sum which can be used for other much needed tooling.
?
Maybe the problem is that we simply cannot have everything?
?
In my case (YMMV) the real problem to solve is losing head alignment when having to raise/lower the head.
The limited travel provided by the quill cannot be solved so raise/lower it is.
?
If the alignment problem gets solved, I'd be more than happy to permanently surrender the possibility of swinging the head.
After all, it is rather worthless when using the Unimat 3 milling table with its small size and limited travel.
See attached file u3_milling.jpg
?
So I came up with a possibility I'd like to ask the group's opinion about.
?
---
?
1.
See these two views of the quill holder (part A3Y 100 010). ?
See attached files qholder_0.jpg and qholder_1.jpg ??
?
For reasons, the quill holder is has a conical hole in it.?
I can understand the conical part of the hole, it is the mere existence of a hole in that part/place baffles me.
?
2.
See this front view of the headstock adapter (part A3Y 100 020).
See attached file hadapter_0.jpg
?
As we all know, the quill holder is inserted into the headstock adapter and is locked in and tightened in place by a M6x30 allen head screw.
ie: loosening the allen head screw allows the holder to be tilted, separation of the quill holder from the headstock adapter requires the removal of the allen head screw.
?
3.
I was curious to see just how these two parts registered against each other so I got out the blue, painted the surfaces and tested them.
See attached files register_0.jpg and register_1.jpg
?
Comparing photo of hadapter_0.jpg with register_1.jpg shows that besides the two cylindrical surfaces of the quill holder (which fits quite tightly into the headsock adapter) the only other surface which registers is the one to right next to the scale.
ie: no other part of the quill holder registers anywhere.
?
The amount of material separating the bottom of the headstock adapter (see bear and number 87 in hadapter_0.jpg) from the actual column is an incredibly massive ~3.0mm.? 8^¡ã
?
The idea I came up with is this one:
?
Why not use the hole in the quill holder to lodge (locktite or similar) a ?10mm rod (hard bronze, like a gib?) which would run in a 10mm x 5mm track milled into the ?28mm column. (just an idea for a number, maybe 10mm is too much)
?
As the holder/headstock adapter pair are assembled (would have to be in place), the rod would go into the 10mm x 5mm track milled into the column and keep the quill holder/headstock adapter pair in aligned.
?
The only problem I see with this is that the conical hole in the quill holder (~8mm at the bottom, ~10mm at the top and 30mm deep) does not look like it has been machined, meaning that getting the rod properly centered with respect to all the axes at play means lightly machining the cone or machining the rod after being locktited on the quill holder.
?
See attached file sketch.jpg to get a rough idea of what I meant with all this.
?
I'd appreciate any input/suggestions.
?
Best,
?
JHM

qholder_0.jpg
qholder_1.jpg
hadapter_0.jpg
register_0.jpg
register_1.jpg
sketch.jpg
u3_milling_1.jpg

Re: Triangular Gib Key For Unimat Vertical Column

 

Hello, Carl!
Regarding the true center of a threaded shaft, if the thread was single point turned
and threaded in the same setup on the lathe it can be then be assumed to be on true center of the thread. If not all bets are out the window.
Just me Two cents worth!
Dick
--
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?SMALL TURRET TOOL POST PLANS?
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Re: Looking for collets from mystery collet holder

 

As always, many thanks for your exhaustive reply, Keith.
?
Jan van der Laan, who is also on this forum, had suggested to me basically the same thing. According to him too, the collet system is a dead length type, for which he provided (in Dutch). Seeing that it was called there a QTH 161E, I searched for that term, which then led me to QTH for Traub lathes.
?
I am glad that my set of collets is now a few steps closer to identfication. Not sure whether I will try to push stock through the collets, though. As it is, they are quite precise so for the time being I simply use them as "normal" collets. Just missing collets of size 1, 1 1/2, 7 and 9 mm but I am happy to have this set anyhow. One final consideration though - the set came in a sale which also contained the EMCO Unimat clockmaker's package, Could it be that horologists might have seen a use for these dead length/push type collets?
?
Herman?

Op 03-12-2024 07:13 CET schreef Keith S. Angus via groups.io <keithsangus@...>:
?
?
I have a box of collets like these, but bigger, probably as described on your linked page. I always assumed they were the sort of collets you would use in a machine having a bar feed through the headstock. They can be arranged to close from behind so they don't retract, so the bar doesn't move back when you tighten the collet. The set I have came with an old Myford, which had no holder or anything else which could be used with them. Thanks to your link I can at least identify them. I've seen lots of these around but never seen them used.
?
Looking around I found this link which includes the title of the standard - Collets - dead length type. This suggests that My earlier thoughts are along the right lines. Looking further I find which shows them being used on bar feed machines, and just about shows how they operate.
?
This leads me to think abut the collets or whatever that are used on NC lathes, where I've seen them feeding the bar through while turning it to size, so the bar moves past the toolbit, which stays still. So the collet has to relax enough to let the bar slide, but maintain drive and concentricity. Something clever going on.
?
Anyway, the DIN 6343 seems to cover a limited range of sizes. Maybe another standard covers smaller ones, or someone decided to make some similar to the standard ones. Then again I suspect quite a range of these collets were made before the standard existed, and I bet each manufacturer made theirs a bit different to everyone else, so you couldn't easily switch to a different supplier

Re: Looking for collets from mystery collet holder

 

I have a box of collets like these, but bigger, probably as described on your linked page. I always assumed they were the sort of collets you would use in a machine having a bar feed through the headstock. They can be arranged to close from behind so they don't retract, so the bar doesn't move back when you tighten the collet. The set I have came with an old Myford, which had no holder or anything else which could be used with them. Thanks to your link I can at least identify them. I've seen lots of these around but never seen them used.
?
Looking around I found this link which includes the title of the standard - Collets - dead length type. This suggests that My earlier thoughts are along the right lines. Looking further I find which shows them being used on bar feed machines, and just about shows how they operate.
?
This leads me to think abut the collets or whatever that are used on NC lathes, where I've seen them feeding the bar through while turning it to size, so the bar moves past the toolbit, which stays still. So the collet has to relax enough to let the bar slide, but maintain drive and concentricity. Something clever going on.
?
Anyway, the DIN 6343 seems to cover a limited range of sizes. Maybe another standard covers smaller ones, or someone decided to make some similar to the standard ones. Then again I suspect quite a range of these collets were made before the standard existed, and I bet each manufacturer made theirs a bit different to everyone else, so you couldn't easily switch to a different supplier
Re: UPVLA ?

 

Hello:
?
On Mon, Dec 2, 2024 at 01:45 PM, Julius Henry Marx quotes himself:
But I found these 72 individual posts ...
And a photograph ...?
?
Here.
At groups.io???? 8^D
?
See the thread here.
?
Best,
?
JHM
Re: UPVLA ?

 

Try this photo album:?/g/Unimat/album?id=195752

Bill in OKC?

William R. Meyers, MSgt, USAF(Ret.)

Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better.
Expect in one hand, expectorate in the other. See which one gets full first.



On Monday, December 2, 2024 at 10:05:45 AM CST, Julius Henry Marx via groups.io <sawbona@...> wrote:


Hello:
On Mon, Dec 2, 2024 at 11:40 AM, OldToolmaker wrote:
Does anyone on this forum remember the ¡°UPVLA from the old Unimat ...
No.
I'm one of the new kids.
?
But I found these 72 individual posts, probably many from the same thread (?):
?
?
But names there may help.
This was a ~US$275.00 attachment back in 2013 ... 8^¡ã
But it seems to have had a strong demand, a clear indication Emco's lack of foresight / design criteria.
?
Specifically these posts may be of use:
?
Best,
?
JHM
Re: UPVLA ?

 

Hello:
On Mon, Dec 2, 2024 at 11:40 AM, OldToolmaker wrote:
Does anyone on this forum remember the ¡°UPVLA from the old Unimat ...
No.
I'm one of the new kids.
?
But I found these 72 individual posts, probably many from the same thread (?):
?
?
But names there may help.
This was a ~US$275.00 attachment back in 2013 ... 8^¡ã
But it seems to have had a strong demand, a clear indication Emco's lack of foresight / design criteria.
?
Specifically these posts may be of use:
?
Best,
?
JHM
UPVLA ?

 

Does anyone on this forum remember the ¡°UPVLA from the old Unimat forum that was owned by Martin Pinkny who lives in Florida?
He bought a UPVLA?
That device was very well done.
If I am the only one who remembers then I must be very old indeed.
Dick
--
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?SMALL TURRET TOOL POST PLANS?
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Looking for collets from mystery collet holder

 

Good day,
?
Would anyone have an idea about the collet system for the attached collets and collet holder? I got these in a lot of unassorted tools and had to produce a new back plate - which had been missing.
?
Someone suggested to me today that the collets bear some resemblance to , but the collet angle and dimensions on mine are different. I will give these here:
?
d = 16
L = 29,9
A = 16,4
D = 20,8
¦Á = probably 25o
?
?
?
?

Bare colletholder.jpg
Bare colletholder viewed askance from above.jpg
Colletholder with collet, retaining cap removed.jpg
Colletholder with collet mounted.jpg
Collets runing from 2mm to 10mm.jpg

Re: Triangular Gib Key For Unimat Vertical Column

 

Hello:
?
On Sun, Dec 1, 2024 at 07:18 PM, John Hutnick wrote:
... very inexpensive ...
Indeed ...
But the prices I see vary greatly.
Of course, it all has to do with the quality of the casting and posterior milling.
?
Prices aside, I think I have run into a problem with these parts.
?
While the SB200 et al. mounting column is ?25mm, Emco saw it fit to improve rigidity, increasing the section for the new Unimat 3.
Unfortunately, the new diameter chosen for the improved Unimat 3 milling column turned out to be a nice but strange ?28mm.
?
That poses a problem when wanting to use that SHF25 part.
ie: it won't fit without some surgery.
?
Although we are only looking at shaving 1.5mm on the lathe, I expect that it needs to be a very precise operation.
It seems to me that it is critical that the relationship between the central (?25mm) guide and the mounting (?7mm) holes be maintained for the whole arrangement to work as intended. ie: perfectly aligned centres in all the parts to be used -> all parts perfectly aligned after machining.
?
The seller of one of the more expensive options offered at AliExpress argues for the quality of their product which costs ~US$4.71 shipping included but if you purchase a lot of 20. I have nevertheless inquired about the posibility of a lot of 4 pcs.
See attached screen captures.
?
There are many other options, some as low as US$1.33 in a pack of 4 but I think the seller clearly makes a point to consider.
?
That said, how would I go about machining the three / four parts I would have to use to match the ?28mm section of the U3 column?
?
Best,
?
JHM

SHF25.jpg
shf25_quality.jpg

Re: Triangular Gib Key For Unimat Vertical Column

 

Hello Bill:
?
On Sun, Dec 1, 2024 at 09:15 PM, Bill in OKC too wrote:
... have a pair of 12mmx600mm rods sitting here ...
Thanks for the offer, much obliged. 8^)
As I may have mentioned before, in the last few years the USPS has become very expensive for shipping anything abroad.
Fortunately I can get that type of round linear locally and avoid the import tax on the whole thing (item+shipping cost).
?
Best,
?
JHM
Re: Triangular Gib Key For Unimat Vertical Column

 

Just looked at a mill for sale - I think it was Schaublin, and definitely not cheap. The round column had a square key on it to prevent rotation but then the entire column could be rotated in its base. This requires a good sized well fitting base, but it gives a good solution regardless of the type of key used. The column could even be square above the base. Can't see a good way to apply it to any Unimat I've ever met.
Re: Triangular Gib Key For Unimat Vertical Column

 

This device brought back a memory of a device years ago called something like UPLA. Does this sound somewhat familiar?
A few were sold on EBay and were somewhat expensive.
--
http://www.homemadetools.net/forum/?OFF-SET-tailstock-center-65965#post105972
?SMALL TURRET TOOL POST PLANS?
?LARGE TURRET TOOL POST PLANS
?MINI-LATHE CARRIAGE LOCK PLANS
?SMALL QC TOOL POST PLANS?
?QUICK CHANGE LATHE TURRET
?MINI LATHE COMPOUND PIVOT MODIFICATION
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