Re: What is the Best Unimat ? and WHY !
Hello Steve,
I'll write up a new thread showing images of what I have done, the Indexer and controller I made so I could move between different machine's CNC, Miller, Lathe it has it's own power supply it is so easy to move and setup to use.
I wanted a small lathe to use for clock work and some miniature wood work at a later date and came across the little cast SL which is just right, but what I did not like was having use a lot of time moving the axis by hand so I came up with make new bed bars to fit the stepper motors and found the single axis controllers from China and they work fine takes a little thinking to set them up but works well, and yes the steppers are through shaft which helps sometimes.
Phill
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Re: Unimat pc basic: question on dead center / alignment bar
For reference this is a picture of the unimat pc tailstock spindle. It has m14 threads for screwing on chuck / collet / live center.?
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Unimat pc basic: question on dead center / alignment bar
Hey all
Bit by bit I'm learning more about my lathe (as a total newbie)?
I'm moving to the point where I'm trying to align my tailstock and have but a couple of stumbling blocks?
- I dont have any form of alignment bar (length shd be approx 150mm to fit in the unimat pc)?
- I don't have any Dead centers
Questions?
1. Are the dead centers for unimat pc the same as unimat 3? Ie. Non tapered and must slide them into spindle? If so I'll find unimat 3 dead centers online.?
2. Is the mounting of dead center as simple as sliding them into the spindle? If so Won't it be loose / have play?
3. Any online options for an alignment bar that stretches the full working distance of the unimat pc? By measurement it's abt 150-180mm
4. Unimat pc has an eccentric off center spindle on tailstock that allows adjustment supposedly in one axis (to front / rear of) Wouldnt this? adjustment would move the center point in both horizontal and vertical directions?
Any advice is much appreciated :)?
JP
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Interesting - I¡¯ve been kicking that idea around for a while. The old 1900s collector toy trains are pricy items, but can I build something similar? Good question. Right now I¡¯m wondering if I can mill slots into the semi-solid barrel armature from a hysteresis motor. It has a laminated field frame, bearings and enough room to add a commutator. Almost done, hah!
chestofbooks.com has reprints of those old Popular Mechanics articles, including some motors. Here¡¯s one example:?
DW
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Re: Emco Unimat 3 Lathe Attached To Wooden Box/ Accessories for auction on Goodwill site.
Hi Gang:
Do check on shipping, the lathe is in Alaska!
Carl.
On 04/07/2023 12:29 PM Richard Burrows <bluerandonee@...> wrote:
There ia a?Emco Unimat 3 Lathe Attached To Wooden Box/ Accessories for auction at the Goodwill site.
The auction ends at??04/07/2023 07:46:00 PM PT.
Richard B.
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Re: What is the Best Unimat ? and WHY !
Hi Phil,
I really like your power feed setup, and am intrigued by your dividing head index controller.? Could you post more information and pictures? I'd like to explore this, but haven't had any practical experience in cnc/electronic lead screws. Have you posted any writeups or videos on this anywhere?
Cheers,
James
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Re: What is the Best Unimat ? and WHY !
Hi Phil, I'd love to see more pics of your setup, hi-res if possible, as I plan to do something very similar. Especially interested in the indexed divider, am thinking about the same for my vertical mill setup (I have 2 SLs). Are those steppers with a thru shaft? I've not seen them before, would be interested in where you sourced them.
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Emco Unimat 3 Lathe Attached To Wooden Box/ Accessories for auction on Goodwill site.
There ia a?Emco Unimat 3 Lathe Attached To Wooden Box/ Accessories for auction at the Goodwill site. The auction ends at??04/07/2023 07:46:00 PM PT. Richard B.
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
I forgot to add I looked at adding plastic washers but guessed they might wear in time, I don't like the bent compression washers I think that would introduce some movement, I think by adding a hardened washer then the roller then a washer it has worked by far the best, cost a few ?'s or should I add $'s but that is it now I can go on and enjoy the lathe.
Phill
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
Hi Dick, I never gave it a thought about making two like you have I just went looking at bearing supplies and found just what I was looking for, it has improved my little lathe 99% I don't have any problem with back lash on the screws and nut they are working really well.
?
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
On my 7x16 minilathe I made a small ball thrust bearing on the cross slide and was able to remove virtually all back lash on the cross slide of my minilathe. It was made from tiny loose balls in a circular groove. I see no reason this could not be adapted to the Unimat cross slide.
Dick
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
Additionally it¡¯ll add friction to a point in the system where you really don¡¯t want additional friction.?
I find the best thing is to make a small washer out of a piece of plastic shim stock. ? That seems to smooth out the surface between the knob and the casting a little. ? I did that on my 3 in 1 mill which uses the same technology as the SL.?
But in the case of my Unimat, most of the backlash is the result of wear in the cross slide on both axis.? That would be more trouble to fix than it is worth.?
Hi:
The problem with the wave washer is, under a cutter load the side force will collapse the washer and the cutter path won't be straight.
Carl.
Perhaps using a curved, or wave, disk spring washer under the handle would give enough pre-load to minimize the backlash.
Something similar to one of these:
Richard B.
-- Quinn Golden
603-491-1451
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Hi Jeff:
The usual method is to take two motors apart and combine the stampings. I have used my Unimat to rewind a small can motor for one of my Lionel trains. I used my Erector set motor to turn the spindle slowly, a counter to keep track track of the windings. I made a holder on the face plate to hold the armature. The motor worked fine. Also counted the windings when I took the damaged wires off.
Carl.
On 04/06/2023 2:55 PM Jkle379184 via groups.io <jkle379184@...> wrote:
The hard part would be the layered sheet steel stampings for the armature. You need them for it to work instead machining a solid armature.
?Jeff
-----Original Message-----
From: Steve Johnson <steve@...>
To: [email protected]
Sent: Thu, Apr 6, 2023 12:24 pm
Subject: [Unimat] Electric Motors #db200
I've been musing about building a small electric motor from scratch on my Unimat SL.? Just for the fun of it and to learn something new. Seems like a doable project, including using the lathe to assist with the windings. Anyone on the list done anything like this?
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
Hi:
The problem with the wave washer is, under a cutter load the side force will collapse the washer and the cutter path won't be straight.
Carl.
On 04/06/2023 1:01 PM Richard Burrows <bluerandonee@...> wrote:
Perhaps using a curved, or wave, disk spring washer under the handle would give enough pre-load to minimize the backlash.
Something similar to one of these:
https://www.mcmaster.com/9714k323/
Richard B.
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
Hi Gang:
To improve the casting is just half of the job, you need to improve the runout on the knob. Both can be corrected with a file. Use some Persian Blue, coat the back of the know and run it up to the carriage. Look for where it rubs off the know and onto the carriage. File both spots down un till the Blue rubs off the whole knob and onto the whole casting. A bent lead screw will mess this up some, but it should help.
Carl.
On 04/06/2023 9:37 AM Quinn Golden <quinngolden@...> wrote:
When I rebuilt my SL, reducing the backlash as much as possible was a goal. However, there was a point of diminishing return as the hand wheel rubs against a rough uneven casting. With any flex in the screw train that gives a ¡°tight spot¡° as the hand wheel is rotated, exacerbating the problem. I tightened the hand wheel until it touched the casting, put on the nut and then tighten them together by hand, felt it then after a few tries gently tightened the nut. I had hit the ¡°sweet spot¡° that seems to work best. So short of machining that piece of casting behind the hand wheel to make it smoother, one needs to revert to the old primitive machining days of always moving your cutting tool into the work piece. Which is to say, you always back off a couple of turns on the handle and then go forward to remove the backlash and make your cut. ?I think that the casting is a poor enough bearing surface, so even placing thrust washers behind it would not illuminate the ¡°problem¡±. ?
That is to see if you consider it a problem, which I really do not. Anything that uses a lead screw into a tapped casting is going to have backlash. It is actually engineered that way.?
I have equipped my Unimat with dial indicators on both axis ?to enable me to see the backlash with every cut made.?
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The hard part would be the layered sheet steel stampings for the armature. You need them for it to work instead machining a solid armature.
?Jeff
-----Original Message-----
From: Steve Johnson <steve@...>
To: [email protected]
Sent: Thu, Apr 6, 2023 12:24 pm
Subject: [Unimat] Electric Motors #db200
I've been musing about building a small electric motor from scratch on my Unimat SL.? Just for the fun of it and to learn something new. Seems like a doable project, including using the lathe to assist with the windings. Anyone on the list done anything like this?
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Re: Unimat black crackle jig-saw
Hammertone paint used to be considered a very rugged industrial coating that was also oil and solvent resistant.
?Jeff
-----Original Message-----
From: g steinback via groups.io <Gsteinba52@...>
To: [email protected] < [email protected]>; alan.ehrlich@... <alan.ehrlich@...>
Sent: Thu, Apr 6, 2023 12:53 pm
Subject: Re: [Unimat] Unimat black crackle jig-saw
Thanks Alan, I stand corrected (I'm in the US.)
Personally I would have preferred a machine gray finish on my DB200 (maybe if I ever have to repaint it) and wonder why the hammertone silver/green was used. There was a note on one of the product descriptions suggesting that hammertone paint 'hid' slight surface imperfections better than a flat paint - even though the Unimat castings seem very well done.
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
Just to confirm, what is this cross slide nut material?
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Re: Unimat 3 / PC Cross Slide Backlash from HANDLEWHEEL
Perhaps using a curved, or wave, disk spring washer under the handle would give enough pre-load to minimize the backlash. Something similar to one of these:
https://www.mcmaster.com/9714k323/
Richard B.
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Re: Unimat black crackle jig-saw
Thanks Alan, I stand corrected (I'm in the US.)
Personally I would have preferred a machine gray finish on my DB200 (maybe if I ever have to repaint it) and wonder why the hammertone silver/green was used. There was a note on one of the product descriptions suggesting that hammertone paint 'hid' slight surface imperfections better than a flat paint - even though the Unimat castings seem very well done.
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Dave W
Carl
Steve Johnson
OldToolmaker