Alternative motor for the Unimat SL
Good evening,
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This is my first post to the site so apologies if I ramble a little.
First of all, many thanks to all involved in sorting out the recent situation.
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I am a retired combustion engineer from the steel industry and have developed an interest in the repair of grandfather clock movements.
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Very quickly it became apparent that some form of lathe was required for this and after much internet searching, during which I found this site, went for the EMCO Unimat SL due to it's compact size.
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After repairing, repainting and general repairs the original motor was refitted but I found it too noisy and time restrained.
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The lathe also came with an old 90w sewing machine motor controlled via a foot pedal.
I tried this but it proved problematic due to not being able to control my left foot and the old motor was not powerful enough to achieve higher speeds under load.
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After research I bought a 230v 550w DC servo motor from Amazon, designed for an industrial sewing machine.
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It was simplicity itself to fit and is more than adequate for my needs. Very quiet, up to 4500 rpm and reversible at the touch of a button.
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It comes with sufficient brackets to fit most needs. I inverted the original motor bracket and mounted it through the idler pulley bearing hole. This gives the ability to adjust belt tension as well.?
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It has a very efficient electrical braking system, sensible as it is designed for a sewing machine and an operator would not want it to run on if they were in difficulty.
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It will stop, with a thump, from 4500 rpm to zero in the blink of an eye.
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Unfortunately for a Unimat SL this leaves more than enough momentum in the chuck for it to screw itself off and end up anywhere in the workshop, at speed.
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This motor braking is simple to turn off in the parameters of the controller, but by default it is set to maximum.
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The normally foot pedal activated on/off and speed control switch was fitted in an appropriate place for hand operation and the return spring removed.
This switch increases the motor speed in steps from 0 to 100% of the desired speed set in the main motor controller. It does this with a Hall effect sensor with a magnet.
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There is a hole in the top of the switch and this means it does occasionally get swarf on it and in it. This would eventually cause electrical problems.
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As part of a normal lathe clean down I inspect and remove any debris to avoid this.
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Some photographs of the setup have been included for your perusal.
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I am very happy to provide any information you may require.
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kindest regards,
David
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Re: Helping Beginners start....
Here's a simple project that may appeal to some
-Guy-
On November 7, 2021 at 1:15 PM Tamra <tamrabrogdon@...> wrote:
Bill, nice attachment... perhaps we can load this in the files.
I've not once used a center punch.? I've used a nail set many times when we have put up moldings.
Still learning...? I can see the usefulness of a center punch, having a wandering drill bit experience
multiple times in my life, even with a manual pin drill...?
its humbling to miss the obvious.
Dick, what is turning to a shoulder?? Is this applicable in Bill's center punch plans?
Eugene, does any of this have any interest for you?? I know the uni is a cool tool and I do know it can take a while to bond with a lathe... It took me about 4 years to bond with my jet VS wood lathe, but once I did, I have a list of things to create in wood...first things first... is what do you want to make, and then what skills do you need to accomplish that project?
There is a book for unimat projects that you can consider as your basic course of cool things to make.??
Who said this in our group?? Certainly there are tool collectors, people who make tools for the tools, and people who use the lathe for other projects...
I limit my interest to making tools when it helps me make my other projects....
Tamra
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Re: Helping Beginners start....
Wow - I'd love to have one of those!
On November 6, 2021 at 9:22 PM Pete <pmerriam9@...> wrote:
John/Tamra
I believe the German u-boats might have carried the Hommel UWG lathe, seen here:
These were very interesting machine tools.
Peter
On 11/6/2021 10:04 PM, John Pratchios wrote:
Tamra;
It has been said that German U-Boats carried a small metal lathe similar to Unimats.
I remember seeing the American Edelstaal Unimat advertised in the ads in the back of Popular Mechanics and Mechanix Illustrated magazines in the very early ¡®60s.when I was a teenager (I¡¯m now 73). The price was $99 at the time. I wanted one very badly back then but $99 was a lot back then.
I did get one in 1971 when my newly wed wife¡¯s Uncle who worked at Sears could get a great discount at Sears who was selling them at that time. I still only ended up with a very basic SL-1000 with a couple of accessories. Since around 2000 I added accessories obtained on eBay and now have most of what I ever wanted, but now I want to convert one to CNC.
Best regards,
John
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Re: Helping Beginners start....
I would love to hear more about knurling in general.
At this?point I do not have a knurling tool. It's?a skill that I would like to acquire though. I have searched for a scissor style tool that would fit my Emco Unimat 3. I believe I need a tool with a 1/4" shank but so far no luck.
I have also never understood completely?how the pattern repeats as the work rolls under the tool. It seems like unless you had a circumference that was a perfect division?the pattern would smear.
Hopefully this makes it through - first post, one of the ones that tried before. Loving this beginners?start - exactly what I need,
Eric
On Sun, Nov 7, 2021 at 7:38 PM Dave Seiter < d.seiter@...> wrote:
I'm still trying to make descent knurls...? I have three scissor types, one being hand held, and a boxfull of different dies, but just when I think I'm going to do a good job, it goes sideways.??
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Re: Helping Beginners start....
Bill,
Forgetting our last measurement is common amongst us older folks.?
The old adage is ¡°measure twice - cut once¡±
Sometimes I end up measuring 3 times.
Dick
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Re: Annual $220 Group fee.
Hi Martin, donation sent through Paypal. If you require more please let me know. Many thanks, Mike Szreider.
I will certainly not turn down donations. Last year there was about $35 left over.
If anyone wants to contribute, send to my PayPal account at mdupreno1@...
Thanks everyone!
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Re: Annual $220 Group fee.
Hi All
Many thanks to Eugene for his very generous donation towards the annual fee, perhaps Martin will confirm sufficient funds have been donated to cover
the cost for the next year.
If this is the case then no further donations are necessary at this time.
Marcus
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Re: Helping Beginners start....
Mr. Pete222 has a series of videos on how to grind the tools for lathes. Here is the first one:
??He uses a wooden model to show the correct angles for a right-hand turning tool, which is about the most commonly used lathe tool. Mert Baker used to sell a set of these that he made himself.?
Here's a search on Tool Bit Grinding Mr. Pete222
It includes the four main videos he did, which are set up mostly for the larger hobby lathes by South Bend, Atlas, Logan, and Montgomery Ward. There are also links to BlondiHacks. She has a slightly larger import lathe, similar to the 7x and 9x lathes. You can learn a lot from her videos, too.?
Watch the videos, and look for recommendations from those folks, to give you more info. Or you could cheat, like I did, and take a class. ;) The class I'm in taught us how to grind our own tooling, and they used 3/8" mild steel for practice materials before we did the real high speed steel (HSS). That being the size tooling we were using in the class. You might want 1/4" or 1/8" stock, depending on what you have as tool holders for your lathe. Harbor Freight has sets of 5 small HSS tool blanks. Item 40641, Drill Master mini tool bits.???There is one each 1/8", 3/16", and 1/4" square 2-1/2" bits, a 1/4" round bit, and a 1/16x1/2x4-1/2" parting tool blade. You can use them as cutting tools, parallels for a milling vise, and a couple of the round bars could be used for gauging small dovetails, among other things.?
Mr. Pete222 talks about the South Bend and Atlas lathe books. They are available free as PDF files on the internet. Archive.org has a lot of the old (late 19th & early 20th century) books on machining, and they have helpful info, too. The ones from about 1924 and earlier are out of copyright.?
You will need some sort of bench grinder, or a belt sander can do many of the things a bench grinder can do, and they often make it easier to set angles, and use finer grinding media.?
You can also buy pre-ground tooling in high speed steel from MicroMark.?? For what a couple sets of those cost, you can buy a small grinder, and a bunch of the unground tools from HF.?
HTH!
Bill in OKC
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Re: Helping Beginners start....
I'm still trying to make descent knurls...? I have three scissor types, one being hand held, and a boxfull of different dies, but just when I think I'm going to do a good job, it goes sideways.??
Speaking of dies, about a year ago I found a partial set of dies that are meant to cut parallel lines on a small handle or shaft by pressing the rod through the die.? I'd never seen nor heard of such a tool before.? Came from a Bulova factory, and may have been made in-house.
-Dave
On Sunday, November 7, 2021, 05:53:58 AM PST, OldToolmaker via groups.io <old_toolmaker@...> wrote:
I think a good beginning project for the Unimat would be to make a center punch.
The skills learned would involve:
(1) straight parallel turning.
(2) taper turning.
(3) turning to a shoulder.
(4) knurling (if you have a scissor knurling tool.
(5) facing.
These are all basic operations and when taken in small steps are easier to master.
Dick
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Re: How to contact Group Owner?
Kevin Groenke @ PersonMakeObject
Info for members having trouble posting:
A common reason for inability to post to groups is attempting to send from a different email account than they are registered under.? If your messages aren't posting, confirm the email address you're sending from.
Kevin Groenke
human of planet earth
Hi Keith
Ian Adam is an Unmoderated listed member from 2009 so there should not be any problem with him uploading messages.
Marcus
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Re: Helping Beginners start....
Hi Gang:
Don't forget heat treating, a soft steel center punch won't stay sharp long.
It might be easier to grind something that is hard allready.
Carl.
On 11/07/2021 8:53 AM OldToolmaker via groups.io <old_toolmaker@...> wrote:
I think a good beginning project for the Unimat would be to make a center punch.
The skills learned would involve:
(1) straight parallel turning.
(2) taper turning.
(3) turning to a shoulder.
(4) knurling (if you have a scissor knurling tool.
(5) facing.
These are all basic operations and when taken in small steps are easier to master.
Dick
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Re: How to contact Group Owner?
Hi Keith
Ian Adam is an Unmoderated listed member from 2009 so there should not be any problem with him uploading messages.
Marcus
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Re: Helping Beginners start....
Hi Gang:
One of my prised tools is a center punch. I was having trouble transfering holes on location. I decided the small Starrett punches just didn't let me punch deep enough. So I made a punch from 3/4" tool steel 6 inches long. With it I can make a 1/4" crater in steel that never misses.?
Carl.
On 11/07/2021 1:15 PM Tamra <tamrabrogdon@...> wrote:
Bill, nice attachment... perhaps we can load this in the files.
I've not once used a center punch.? I've used a nail set many times when we have put up moldings.
Still learning...? I can see the usefulness of a center punch, having a wandering drill bit experience
multiple times in my life, even with a manual pin drill...?
its humbling to miss the obvious.
Dick, what is turning to a shoulder?? Is this applicable in Bill's center punch plans?
Eugene, does any of this have any interest for you?? I know the uni is a cool tool and I do know it can take a while to bond with a lathe... It took me about 4 years to bond with my jet VS wood lathe, but once I did, I have a list of things to create in wood...first things first... is what do you want to make, and then what skills do you need to accomplish that project?
There is a book for unimat projects that you can consider as your basic course of cool things to make.??
Who said this in our group?? Certainly there are tool collectors, people who make tools for the tools, and people who use the lathe for other projects...
I limit my interest to making tools when it helps me make my other projects....
Tamra
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Re: Helping Beginners start....
Thank you all for your suggestions, especially Tamra for the reference suggestions. ?The first things that I'd like to do don't even involve using the machine - they include making the cutters/chisels, learning which to use for what, and how to position them relative to the direction of cut. ?I'm amazed at how little I know. ?But I'd certainly like to get started. ?Thank you all again.
Eugene
On Sunday, November 7, 2021, 01:14:09 PM CST, Jay Perez <jay.perez1@...> wrote:
Hi Tamra,
I have the good fortune to have a 200+ member Makerspace 5 minutes from my house. Lots of diverse talent and everyone anxious to share their knowledge.
I've converted my Unimat to CNC using a GRBL controller and have also been involved in setting up several?CNC Routers using a variety of controllers including Mach 3 & 4 and Linuxcnc.
If you've already mounted and wired up the stepper motors and drivers and have a PC with Mach3 (requires a 32 bit Windows 7 or older O/S) installed you have already done the hardest part !
Configuring the software, microstepping, and motor tuning can be intimidating the first couple of times you do it but it will be much easier and make more sense afterwards and you'll easily master it.
Any good information on setting up a 3 axis router will directly apply to your 2 axis lathe. The biggest difference is how the Work Coordinate System (WCS) is positioned. On most mills the Z axis is the vertical axis and plus is in the up direction. On a lathe the z axis is parallel to the axis of rotation and Z+ is away from the headstock.
I'm available to provide help and encouragement if you'd like.
Jay
There are so many wonderful beginners projects...?
I still haven't made my 1/12th scale oil can from brass... but I want the top to unscrew and I want to hollow it out inside and the tip..... so you know why it isn't done.? All these years later, it can be intimidating to just try things... I like to work in 360 brass - reasonably inexpensive...
But I remember Coach / Mert Baker telling me that I need to learn to sharpen my tool bits and I think that was wise advice.? I'm ok with sharpening my tool bits now, and still haven't made a leather apron yet.... I've got holes in shirts from sparks from my bench grinder... so I've learned and retained a few bits of experience.
So, for all of our very experienced unimat users, what is the beginners project you would like to start.
I still like the make your own miniature cannon project as a beginner's project - was that popular mechanics?? I will have to search the emails.
John, I started to convert a sherline to 2 axis CNC - but got stuck....I should try and work through that again.? I'm to the point of calibrating the steppers in Mach 3 and stopped... got cold feet and then Covid 19 arrived with a multiple miniature chair project and real life got in the way and I haven't returned to the project... Your post is a good reminder, although I walk past that lathe 5 of 7 days a week.? I wish I had a makers space that had some people interested in DIY CNC conversions on lathes... I found that a lathe was the least in demand of CNC Conversions... Wood Router #1, Lasers, Mills, etc, and lathes were at the bottom of the list... To me that is the place to begin with only 2 axis to cut your teeth.? You may want to consider an ELS conversion - and I was considering this for a taig lathe, if I can't finish the Sherline -?
Tamra
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Re: Helping Beginners start....
Hi Tamra,
I have the good fortune to have a 200+ member Makerspace 5 minutes from my house. Lots of diverse talent and everyone anxious to share their knowledge.
I've converted my Unimat to CNC using a GRBL controller and have also been involved in setting up several?CNC Routers using a variety of controllers including Mach 3 & 4 and Linuxcnc.
If you've already mounted and wired up the stepper motors and drivers and have a PC with Mach3 (requires a 32 bit Windows 7 or older O/S) installed you have already done the hardest part !
Configuring the software, microstepping, and motor tuning can be intimidating the first couple of times you do it but it will be much easier and make more sense afterwards and you'll easily master it.
Any good information on setting up a 3 axis router will directly apply to your 2 axis lathe. The biggest difference is how the Work Coordinate System (WCS) is positioned. On most mills the Z axis is the vertical axis and plus is in the up direction. On a lathe the z axis is parallel to the axis of rotation and Z+ is away from the headstock.
I'm available to provide help and encouragement if you'd like.
Jay
There are so many wonderful beginners projects...?
I still haven't made my 1/12th scale oil can from brass... but I want the top to unscrew and I want to hollow it out inside and the tip..... so you know why it isn't done.? All these years later, it can be intimidating to just try things... I like to work in 360 brass - reasonably inexpensive...
But I remember Coach / Mert Baker telling me that I need to learn to sharpen my tool bits and I think that was wise advice.? I'm ok with sharpening my tool bits now, and still haven't made a leather apron yet.... I've got holes in shirts from sparks from my bench grinder... so I've learned and retained a few bits of experience.
So, for all of our very experienced unimat users, what is the beginners project you would like to start.
I still like the make your own miniature cannon project as a beginner's project - was that popular mechanics?? I will have to search the emails.
John, I started to convert a sherline to 2 axis CNC - but got stuck....I should try and work through that again.? I'm to the point of calibrating the steppers in Mach 3 and stopped... got cold feet and then Covid 19 arrived with a multiple miniature chair project and real life got in the way and I haven't returned to the project... Your post is a good reminder, although I walk past that lathe 5 of 7 days a week.? I wish I had a makers space that had some people interested in DIY CNC conversions on lathes... I found that a lathe was the least in demand of CNC Conversions... Wood Router #1, Lasers, Mills, etc, and lathes were at the bottom of the list... To me that is the place to begin with only 2 axis to cut your teeth.? You may want to consider an ELS conversion - and I was considering this for a taig lathe, if I can't finish the Sherline -?
Tamra
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Re: Helping Beginners start....
Tamra, I've been going to a school for precision manual machining for over 6 years now, very part-time. Every time I watch her videos, I learn something new. It will be easier and faster for her to do some things on her much larger lathe, but anything she can do, you can do, just perhaps a bit slower. To me, the key skill is getting accurate measurements. Not being able to do that was why I was having so much trouble with my HF 7x10. I wasn't getting accurate measurements, so my parts weren't ever the right sizes. With a little care, I can get within .0001" or 1 ten-thousandth. now. Most stuff a machinist will make only needs to be with about .005, or 5 thousandths. That's a common tolerance on stuff for mass production. One of the reasons I've been taking so long in my class was trying to get to the tighter precision levels. And another couple of reasons are getting in a hurry, or forgetting what I measured last. Neither have good results for me.?
Bill in OKC
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Re: Helping Beginners start....
Hi John,
We have two of the DB200/SL1000 models. I converted one to CNC. A small amount of info posted on YouTube.
Jay Perez
Tamra;
It has been said that German U-Boats carried a small metal lathe similar to Unimats.
I remember seeing the American Edelstaal Unimat advertised in the ads in the back of Popular Mechanics and Mechanix Illustrated magazines in the very early ¡®60s.when I was a teenager (I¡¯m now 73). The price was $99 at the time. I wanted one very badly back then but $99 was a lot back then.
I did get one in 1971 when my newly wed wife¡¯s Uncle who worked at Sears could get a great discount at Sears who was selling them at that time. I still only ended up with a very basic SL-1000 with a couple of accessories. Since around 2000 I added accessories obtained on eBay and now have most of what I ever wanted, but now I want to convert one to CNC.
Best regards,
John
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Re: Helping Beginners start....
I looked up turning a shoulder... I did not know the name of this skill.
I think I need to go watch the blondi hacks series on YouTube...
Tamra
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Re: Helping Beginners start....
Bill, nice attachment... perhaps we can load this in the files.
I've not once used a center punch.? I've used a nail set many times when we have put up moldings.
Still learning...? I can see the usefulness of a center punch, having a wandering drill bit experience
multiple times in my life, even with a manual pin drill...?
its humbling to miss the obvious.
Dick, what is turning to a shoulder?? Is this applicable in Bill's center punch plans?
Eugene, does any of this have any interest for you?? I know the uni is a cool tool and I do know it can take a while to bond with a lathe... It took me about 4 years to bond with my jet VS wood lathe, but once I did, I have a list of things to create in wood...first things first... is what do you want to make, and then what skills do you need to accomplish that project?
There is a book for unimat projects that you can consider as your basic course of cool things to make.??
Who said this in our group?? Certainly there are tool collectors, people who make tools for the tools, and people who use the lathe for other projects...
I limit my interest to making tools when it helps me make my other projects....
Tamra
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Re: Helping Beginners start....
Attached is a extract from that book I mentioned, showing the hammer and tap wrench. Mine was made with a 3/8" head, instead of the 3/4" in the book. That was long, long ago, and far, far away, and in another universe, so I couldn't tell you why the variation. Might be a little bit long for the Unimat, too, but if I could have a different hammer head size, anyone else could make whatever variations they wanted.?
Got the power straightened out, need a longer cable for the gigabit ethernet, but WiFi works fine
Bill in OKC
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OldToolmaker
Bill in OKC too
Carl
Tamra