View Full Version : Evan...Unimat??

05-09-2004, 08:39 AM
Hey Evan,
How is the unimat coming? What changes have you made and what have you done with it? Are you happy with it? Fred

05-09-2004, 09:42 AM
Yes, I like it a lot. It has it's place in the spectrum of machining. I will show you what it can do with the small modifications that I have done. I am kind of busy right now with other projects, like mowing the lawn, but I will try to demonstrate what can be done with a few simple mods to the machine.

With the mods I have made I can take a .125" cut in brass without chatter, It is almost like my SB9 on the small stuff.

My imperative is to leave the machine alone, with no modifications. I will make it work better by adding removable accessories.

Give me 'til tonight and I will take some pics of how to improve the rigidity of the Unimat by several degrees.

[This message has been edited by Evan (edited 05-09-2004).]

05-09-2004, 01:29 PM
First, I milled a couple of shim blocks that can be placed under the round stock ways. They give serious rigidity to the the ways and can be moved as needed.


Sneak preview of the rotary table:


A Teflon strip to take up the slack in the cross slide on the Unimat.


With these simple mods it really makes a difference how it turns.

Mike W
05-09-2004, 01:41 PM
That reminds me of my Taig that I have sitting on a shelve somewhere. http://bbs.homeshopmachinist.net//biggrin.gif

Spin Doctor
05-09-2004, 01:51 PM
I've been playing around wth designing a modern alternative to the Unimat bar lathe that would employ linear bearing assemblies for the bed. Of course the cost would be a little exrteme

05-10-2004, 09:33 PM
I don't own a unimat, probably never will. But looking at your pictures, I was wondering if adding an adjustable roller under the bottom of the tailstock would help take out some of the deflection of the ways? Kind of like what his block does under the chuck, but at the other end, to shorten the span considerably.
David from Jax

05-10-2004, 10:38 PM

I use two blocks, one on each side of the carriage. They are ever so slightly tapered so they wedge in under the ways lightly and can be instantly moved as needed. It really works quite well. Also you may note that heavy chunk of aluminum plate the lathe is bolted to. That also helps a lot.

05-10-2004, 11:33 PM
Thanks for the clarification, Evan.
Makes sense to put them where you did, under the chuck.
One other question about Unimats.
What size collets do Unimats use? I bought some E-16's that were listed on ebay under the unimat title. I try to find all of them I can, since they fit some of the Volstro stuff I own. I wondered if that was a mistake in the listing, or if they do fit the Unimat lathe.
Thanks, David from jax

05-11-2004, 01:13 AM

I'm not a Unimat expert and I have no clue what size collets it uses. I'm sure someone here knows.

05-11-2004, 06:47 AM
Unimats had a special spindle which allowed the use of "W-W" collets. These are specific to wathcmakers lathes, but I'm not sure if they were 8mm size. If I could find my Unimat manual, I could let you know for sure. The spindle referred to was an option and had to be changed by the user if my memory is correct.

05-11-2004, 07:42 PM

Is the teflon strip (in cross slide.....3rd photo) taking up vertical or horizontal (left/right....front/back) slack??

Does it move with the in/out motion of the cross slide or is it stationary?

Thanks........(Oh, did I remind you that you do "NICE WORK").


05-11-2004, 07:49 PM
The teflon strip is lightly stuck to the bottom of the cross slide and stops most of the flex of the bars it slides on. It slides with the cross slide.

05-12-2004, 02:03 AM
My manual doesn't say much about the collets for unimat, except that the collet chuck comes with the adapter plate that is threaded for the chuck to allow custom fitting. The picture shows a box of 20 or so collets, which are available in inch or metric. Or should I say were available. There are no numbers given in my manual, except the Unimat thread sizes, which are -headstock and tailstock spindles, M12x1, leadscrews, M8x1. This is for a DB200, though some pics in the manual show SL on the headstock.

05-12-2004, 02:25 AM
DB200 and SL1000 are the same except for the pulleys.

BTW, 12 X 1 mm taps are available from KBC for reasonable $$$.

[This message has been edited by Evan (edited 05-12-2004).]