¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
  1. Unimat
  2. Messages
Expanded Topics Messages Polls
Date
Re: Simple Threading on the Unimat

 

?
Adding the drive required making a new end plate (thicker to act as a bearing) and a new stub shaft with the long fork and groves.
?
It all worked as designed (being a "fair" copy of an earlier design). And was in regular use for machining and threading for a long time. Now not used (well switched on and spun occasionally) as I now have a 41/2 inch boxford together with a Prazimat. Both of which have been fitted with stepper motor drives and electronic threading controls. So sadly the unimat 3 is covered in dust and no longer used.
Re: Simple Threading on the Unimat

 

Theres another way to do thread creation on a unitmat. I have a model 3. A friend had inherited another unimat with a threading attachment that I had not seen before. I duely set out to copy it.
It intails adding a "meccano" toothed sprocket onto the back of the final pulley driving the chuck.
That was then used to drive (via a meccano chain) another spocket on the threaded shaft of the carriage drive. A series of different sized sprockets then gave a range of threads that could be tapped.
?
The"real problems" started at this point.
There is an inversion needed to get a normal RH thread. To do that the "normal" threaded rod that drives the carriage has to be reversed. (normal is LH thread). So a RH threaded rod will do the trick. But the thread in the carriage is cut into the body of the carriage. So the carriage body was drilled out and a threaded bush was installed !! once done more threaded rods and bushes could easily be added to improve the range of threads possible...including LH threads.
One of the "nice" benefits from all of this was that the old very well worn carriage drive was now replaced by a new threaded bush. I also added a section on the front of the bush that could be squeezed by a clamp to remove all backlash. And of course adding a LH imperial threaded rod changed that portion of the lathe to imperial.
?
The next "bit" was to add a toothed gear to the fine feed which was going to drive the carriage driving rod.
?
Simple Threading on the Unimat

 

Threading on the Unimat can be done without special chasing equipment. I am going to make an ER32 collet chuck without any special equipment. I bought a cap screw with the same thread pitch as the ER32 collet and a matching tap. I am going to drill drill and tap a starting hole in my bar stock and use the as my leader. With this setup I should be able to cut a single point internal thread to fit an ER32 ?collet nut I have. If it works as I intend it to I will be home free. We will see how it goes.
Stay tuned!
Dick
--
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
Re: Thanksgiving trip, selling Unimat Accessories

 

US Prices for accessories¡­

indexing attachment, $145?
circular clamping plate, $95
Steady Rest, $140
Collet Chuck, $180, $30 each collet, or $100 for all four.?
Slow Speed Bracket, $180.
?
Shipping via USPS from Thornwood, NY.?
?
let me know BEFORE Tuesday so I can pack them for trip¡­
?
Regards,
Jeff??
Re: Induction Unimat motor?

 

Update.
I since aquired a unimat with induction motor and used it a bit. It is definitely an improvement over more common brushed one. Does not bog down as easily and its the performance is almost as good as my 150W DC. It's got a cooling fan and is probably constant duty cycle. Still, gets quite warm.
Re: Thanksgiving trip, selling Unimat Accessories

 

Should read;
?
¡±that I have locally for sale.
?
On a platform in Canada called ¡°Kijiji¡±?
?
Jeff??
Re: Mistery Unimat 3 with interesting modifications

 

Hello:
?
... gear box on this U3 is powered from the head spindle ...
... with a rubber belt ...
... has a disconnect on the end of the box ...
Sounds a lot like the OEM Unimat 3 power feed attachment (see attached image).
An nicely made albeit quite expensive little thingy, these days going for ~US$250/275 from the usual suspects.
?
Problem is that, being driven by the U3's spindle you have a direct relation between spindle speed and carriage advance.
ie: no fast spindle speed + slow feed.
?
Like I mentioned in another post, the OEM spec o'rings (used as belts) you get these days tend to stretch, as a result the belt slips and you get interrupted cuts, not a good thing.
?
I have been thinking (on/off mode) of a way to solve those two drawbacks by driving it with an independent variable speed motor which can be powered from the same 350W / 24v PS I use with the U3's motor.
eg: a proper belt drive to the existing PF pulley.
?
... fitting a DC direct drive inline to the gearbox drive shaft slung under the end cover ...
The problem with that is that you will have no provision for 'accidents'.
ie: a tool jamming with a direct drive will have no belt slippage to protect the work | tool | motor and/or PWM unit.
?
... would it be better to go as has been made on the lathe in MEW mag ...
Not sure what you are referring to.
?
But I would suggest / am for the idea of taking advantage of what we have (the U3 OEM power feed) and adapt it to be able to use it with an independent motor/pulley belt arrangement and a PWM control.
?
That said, every article I have seen published in MEW has had the virtue of seeming (at least to me) a bit difficult to follow/understand.
A great many, very creative/usefull ideas I have read about usually require tools I don't have at hand, the experience and/or cash needed purchase them.
eg: I finally replaced the bushings on my U3 milling machine but it is still waiting for me to finish the ER collet adapter, the precision vice holders and purchase decent quality milling tools for it. Cheap milling bits are a waste of money.
?
Best,
?
JHM

u3pwr_feed.jpg

Thanksgiving trip, selling Unimat Accessories

 

Hi Guys

Im driving to NY state to see family for American Thanksgiving
?
?
and wanted to see if any group member wanted any of the accessories I have locally brought along so I could ship via USPS FLAT RATE BOX.
ALL PRICES CANADIAN SO NEED TO CONVERT, ABOUT 35% LESS.
Here¡¯s the list of available items:
?
Indexing/Dividing attachment (24 or 48 tooth wheels, $200 with choice of wheel)
Circular clamping plate $130
Steady Rest $190
Collet Chuck & 4 collets. $250 for Chuck, $40 each collet added
Slow Speed motor Bracket $250

Any questions let me know?
?
Cheers,
Jeff??
Added photo album Cut-off Blades #photo-notice

Group Notification
 

Carl <carl.blum@...> added the photo album Cut-off Blades : Two cut-off blades
Re: Mistery Unimat 3 with interesting modifications

 

From: [email protected] [mailto:[email protected]] On Behalf Of Peter Brooks
Sent: 23 November 2024 18:51
To: phill005; [email protected]
Subject: Re: [Unimat] Mistery Unimat 3 with interesting modifications

?

When I changed over to DC motors I built the controller box with two PWM units (the transformer had two 24V DC outlets anyway), with the idea that I could power the lathe and mill at the same time (the mind boggles¡­).

?

For thread milling/grinding ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­?


Virus-free.
Re: Mistery Unimat 3 with interesting modifications

 

I had the standard U3 power feed attachment but didn¡¯t much like it¡­
?
When I changed over to DC motors I built the controller box with two PWM units (the transformer had two 24V DC outlets anyway), with the idea that I could power the lathe and mill at the same time (the mind boggles¡­).
?
So I¡¯ve been considering a direct drive to the leadscrew also. I¡¯m in no rush, plenty of other things to do first but I was thinking of a simple sliding carriage arrangement with a mechanical lever disconnect (as well as the off/on and direction on the controller of course).
?
Just my tuppence / two cents :-)
Re: Mistery Unimat 3 with interesting modifications

 

Many thanks Bill now a member.
?
Phill
Re: Mistery Unimat 3 with interesting modifications

 

Sent you an invite to your email address.

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 Saturday, November 23, 2024 at 11:49:18 AM CST, phill005 via groups.io <phill05@...> wrote:


Hello Bill, could you send me the details to join Mini-Mills group please.
?
Phill
Re: Mistery Unimat 3 with interesting modifications

 

Hello Bill, could you send me the details to join Mini-Mills group please.
?
Phill
Re: Mistery Unimat 3 with interesting modifications

 

Hello Julius,
?
The gear box on this U3 is powered from the head spindle with a rubber belt and it has a disconnect on the end of the box you push it in to drive, pull out to stop, so you have full control with the hand wheel, what I have been looking at is fitting a DC direct drive inline to the gearbox drive shaft slung under the end cover it looks like it will fit.
I have two options I have another motor that has a geared end but the motor would be sticking out.
So still some thinking to do, would it be better to go as has been made on the lathe in MEW mag and take off the the U3 gearbox or go my way under the end cover??
?
I'll get some images tomorrow so you can see what I mean.
?
?
?
Phill? ?
Re: Mistery Unimat 3 with interesting modifications

 

Look at the Mini-Mills group, which I own, and can send you an invite to join, if interested. They have a few things about add powerfeeds to mills, which can be applied with a little skull sweat to lathes. They tend to use a coupler that can disconnect the motor from the feed screw when needed for hand positioning. Ought to be some stuff like that in the 7x12 mini-lathe group. I don't think my mini-lathe group has much of that info, but it does have a bunch of modifications for 7x mini-lathes by Ralph Patterson. Some of that might be a good inspiration for you, even though 7x machines are much larger than the Unimats, even the U3.?

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 Saturday, November 23, 2024 at 10:30:34 AM CST, Julius Henry Marx via groups.io <sawbona@...> wrote:


Hello:
?
@Phill005
... have a Emco power feed ...
?
Yes, so do I.
But it is rather a hassle to use.
Belts (o'rings actually) stretch too easily and slip, interrupting the cut.
Even if you use the right OEM spec. ie: 2-222/N674-70
... drawing up a way of fitting a DC motor ...
Are you looking at a servo motor like those used for turning the U3 to CNC duty?
Or something like a Johnson type RS-555/775/895 with gear reduction?
?
It would have to be an arrangement allowing manual use of the carriage feed when not in use.
?
Best,
?
JHM
?
?
?
?
?
Re: Mistery Unimat 3 with interesting modifications

 

Hello:
?
@Phill005
... have a Emco power feed ...
?
Yes, so do I.
But it is rather a hassle to use.
Belts (o'rings actually) stretch too easily and slip, interrupting the cut.
Even if you use the right OEM spec. ie: 2-222/N674-70
... drawing up a way of fitting a DC motor ...
Are you looking at a servo motor like those used for turning the U3 to CNC duty?
Or something like a Johnson type RS-555/775/895 with gear reduction?
?
It would have to be an arrangement allowing manual use of the carriage feed when not in use.
?
Best,
?
JHM
?
?
?
?
?
Re: Saw blades for the Emco Unimat jig saw accessory

 

Saw blades for the Unimat fret saw are available in most big box stores such as Menards and Home Depot. ?Also known as coping saw blades.
Dick
--
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
Re: Mistery Unimat 3 with interesting modifications

 

Hello Neil:
?
... can't download them?
I received Clive's files but I checked and yours are perfectly accessible.
No problems.
?
Thank you.
?
Best,
?
JHM
Re: Mistery Unimat 3 with interesting modifications

 

Hello Clive:
?
Sent!
Yes.
And received perfectly.
Thank you for that.
?
Best,
?
JHM
?
861 - 880 of 64887