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Hello:

This new member was rummaging through files yesterday afternoon and found this:

/g/Unimat/photo/0/46015.56320.0?p=Created%2C%2C%2C20%2C2%2C420%2C0

I can recognise it as a device to adjust/improve backlash in our dear and very backlashy DB200/SL1000 and Unimat 3.

But that's all.
No text, no details.

Is there a post for it somewhere here?

Thanks in advance.

Best,

JHM

Hello:

Hello:

> ... sure about that?
Yes ...
Although today it has a higher price: US$8.41
Are you looking at the link I posted?

This is what I paid, the total amount reflected both on the confirmation email and my credit card movements:

Motor US$? 7.92
Collet US$? 2.72
S+H?? US$19.58
Total: US$30.22

There was a US$4.00 coupon/discount for orders over US$5.00 somewhere along the line.
ETA ~ early August.

No taxes as the orders is not over? the US$50.00 limit.

Best,

JHM

On Mon, Jun 13, 2022 at 02:26 AM, @juliushenrymarx wrote:

Earlier today I ordered one similar to the one referenced by NapierDeltic in his post.
Only US$7.92.

https://www.aliexpress.com/item/33009729521.html?gatewayAdapt=glo2esp

Are you sure about that? According to my currency convertor that's about 95 USD. Available on Ebay UK for about ?45 from China. Probably taxes and things on top of that. Also says 55 USD.

Hello:

> ... look at my album ...
Will do. Thanks for the heads-up.
> ... used a 130 W ...
Earlier today I ordered one similar to the one referenced by NapierDeltic in his post.
Only US$7.92.

https://www.aliexpress.com/item/33009729521.html?gatewayAdapt=glo2esp

> ... polyurethane belts and found they never slipped.
Yes, I have heard that they don't slip.
But I cannot help but thinking that a slipping belt is a sort of insurance.
And could eventually save a locked lathe.

> ... shock had been efficiently transferred to the motor bearings ...
> ... needed to be replaced (with high quality ones - I suspect the originals were a bit cheap and cheerful).
Yes.
Maybe I should do that directly do it before installing the motor.? 8^/

> ... motors get longer ...
Yes.
The version I ordered is only 80mm long (200W/280mN. m)
I think the 300W version is 172mm long and 400mN. m.
Just over twice as long for ~43% more torque, same diameter.

> ... shafts are 8 mm so a direct fit for the U3 pulley and the fixing screws line up with the slots in the U3 ...
That's good to know.
I also ordered a ER113mm chuck spindle just in case I want to use a different pulley.?

> ... new set of pulleys ...
> ... speed controller for it ...
> ... get the speed nearly right with the belts ...
Yes, same here.

I wonder if there's a power curve graph available for these motors.
It would help in finding the speed range with the highest torque.

Thank you very much for your input.

Best,

JHM

If you look at my album?Keith's DB_SL in Photos you will see the motor type many of us use successfully. I used a 130 W on my SL and it had plenty of power. I can't see why the U3 should need more. I ran it with Doug Feistamels polyurethane belts and found they never slipped. When I did have a problem (big bang - everything stopped) I found the shock had been efficiently transferred to the motor bearings, which needed to be replaced (with high quality ones - I suspect the originals were a bit cheap and cheerful). These motors are available from 100 to 200 W (that I have found). The motors get longer and slower as the power goes up. The one I used on the SL was shorter than the U90 motor, and gave more space around the chuck. They all have the same fixings on the shaft end, but the brushes (and therefore the cable entry) can be at either end. Generally the shafts are 8 mm so a direct fit for the U3 pulley and the fixing screws line up with the slots in the U3, so no mods to the motor plate are needed. The ones with a toothed belt pulley have a better shaft than the ones with a chain sprocket, but the sprocket is easier to get off. If you can find one with a longer shaft that will also be better.

I have a 150 W motor just waiting to go onto my U3, and I don't expect any problems. However I might make up a new set of pulleys, to compensate for the loss of the two speed motor. I do have a speed controller for it, but I like to get the speed nearly right with the belts before tweaking the controller - on the SL I rarely use the controller. Continuous use for an evening did not cause the motor to run hot, just a little warm.

There are a few other photo albums of fitting these motors to the DB/SL, but it is much simpler on the U3. I know it has been done, but it does not require much explanation, drawings, or photos.

Hello:

> ... 150w motor purrs and does not even get warm.
> ... like a safety feature.
Indeed.
And a good one too.

Replacement parts for these thinguies (with all respect) are quite/increasilgly? hard to come by.
And expensive.

One more question if I may, with respect to the PS to use for this motor:

Which one/type/spec do you use in your respective setups?
Any links you could share so I can find one?

Thanks in advance,

JHM

Hello:

I have recently purchased a Unimat 3 and am currently in the process of finding a suitable motor to replace the original 90W one.
I plan to eventually set it up on the grinding column so as to avoid the unmount/mount/mount process each time I need to mill something.

One option I have seen are the ubiquitous 220V/7000rpm sewing machine motors which are supposed to be made for continuous use but, like the original Unimat 3 motor, are at the most rated at 100W, at least the ones I can get locally.

I'd be very obliged if you could share your insight/experience with this spindle motor, which seems to be a much better option.

- Using it @24V, how long can you use it before it needs to cool down?
ie: have you found it to be prone to overheating?

- @200W, it is over 2X the original motor's rating. Have you found it necessary to install an overcurrent protection to protect the lathe in case of a lock-up or jam?

Thanks in advance,

JHM

Thanks for this!

When I first looked at the belts, they seemed like they could be Sherline belts, only a second look showed them to be much too long.? So since they were in the same box as the Unimat bits, I assumed them to be Unimat belts.

But now, I think you may be right, they may be for one of my wife's sewing machines and somehow creeped into MY storage area.? (The nerve!)

As to the handle, it's not bent and it's not rusty.? There is some wear, it has been used, for sure.? The factory "blackening" is gone, but that seems to be all the wear, the surface black.

Anyway, we'll see if anyone is interested.? I'm not about to put them on eBay .. too much hassle, methinks, and I don't really care about the money.? But I need to start minimizing, if only to save my wife some bother.? ?My days may well be numbered (with a smallish number) and it would be a sin to just toss them.

You have the feed handle for a Unimat DB or SL (same lathe for most purposes) and a dead centre for the same Unimats. The centre is not anything special, but the feed handle is much sought after.

The belts are a standard Vee belt commonly used on sewing machines and similar light machinery. I have often wondered whether they could be used on a Unimat, but I never found out. They are easy enough to find on Ebay if you know what size you need.

In summary - belts - probably no interest here.

Centre - someone might want one. Current price $15 (US) for two on Ebay - you rarely need two.

Feed handle - should get a decent price. I'm currently seeing none on Ebay worldwide and it looks to be in good condition - no rust, handle not bent, no visible wear. I think this is very little used, if at all.

Not of any use to me as my SL has gone to Australia and I haven't!

the handle is a unimat part, the center is likely one as well would need to know the shafts size to be sure, the belts i have not seen that style used in any of the unimat stuff I have looked into since starting, they also seem very big? my biggest belt that I have thats pre-made could not fit the handle in it.

good luck in selling them?