Will The $150 Chinese Servo Motors From Ebay Work On An Old Adler 68?

[Vinculus]

In Germany I find 12 mm and 14 mm bores, no 13 mm. I'ld try a 12 mm and a 13 mm drill. Or a 14 and a little bit of sheet metal to fold around the shaft.

Greets

Ralf C.

I found that the Jack motors have a 13 mm. straight bore shaft.

I am wondering, however, if a 15 mm. straight bore could work. The pulley has a notch and the shaft should have the key for this notch, so it's not like a 15 mm. bore pulley will spin around freely. What do you guys think? The pulley might rotate 2 mm. off-center, but otherwise it should work, no?

Could you give me a link to where I can get a 12 or 14 mm. bore pulley?

[Kohlrausch]

Could you give me a link to where I can get a 12 or 14 mm. bore pulley?

http://keilriemen24.eu/index.php/cat/c12295_1008-1008.html

http://www.wdn.de/artsearchresult.php?STICHWORT=riemenscheibe+40&x=0&y=0

http://www.mercateo.com/p/102-238341%282d%29BP/Keilriemenscheibe_aus_Aluminium.html

Seems you can only get 50 mm diameter with taperlocks.

HTH

Greets

Ralf C.

[Vinculus]

Oh well, custom made it is, then.

It'll work itself out eventually I guess.

[dikman]

I must admit that I'm surprised that it's not 15 mm (particularly as it appears to be your basic Chinese servo). We live and learn. The keyway is pretty standard, and is the same on all my Chinese-bought pulleys, plus the locally bought ones (same thing) and also the two generic clutch motor pulleys. As there's only 2 mm difference, you could try some thin sheet tin or aluminium to sleeve the shaft, cutting a slot for the key. If you can get a snug fit then it should be pretty close to centred and tightening the nut should lock it in place. Considering that you don't intend running at high speed it should work fine.

[TinkerTailor]

If you look at the picture, that shaft coming out of the motor is about 2mm wider and then steps down. I think they turned then down for some reason, perhaps due to poor original finish or to use up a bunch of pullys with incorrect center holes with the keyways already cut..

[dikman]

Well spotted, I didn't see that. Guess we'll never really know why it was done.

[Darren Brosowski]

????

The motors originally asked about in this thread use a 15MM bore with 6mm key.

China tends to use one standard and they do not do low volume specials

[Vinculus]

????

The motors originally asked about in this thread use a 15MM bore with 6mm key.

China tends to use one standard and they do not do low volume specials

Yeah, but I didn't end up buying the motor in the first post. Instead I got a Jack JK-513A from College Sewing. Turns out it has a non-standard bore, as seen in the attached picture. I will probably try dikman's suggestion and buy a 15mm bore pulley and wrapping some sheet aluminium around the motor shaft; at least before investing in a custom made pulley.

[Kohlrausch]

????

The motors originally asked about in this thread use a 15MM bore with 6mm key.

China tends to use one standard and they do not do low volume specials

Darren,

do you know how slow the motors of the first post can turn?

Greets

Ralf C.

[TinkerTailor]

Yeah, but I didn't end up buying the motor in the first post. Instead I got a Jack JK-513A from College Sewing. Turns out it has a non-standard bore, as seen in the attached picture. I will probably try dikman's suggestion and buy a 15mm bore pulley and wrapping some sheet aluminium around the motor shaft; at least before investing in a custom made pulley.

Hard to see in this photo, is the hole in the pulley 1/2 inch exactly? If so, a farm supply store, or mcmaster-carr will have a pulley for you. 1/2 inch is really common outside sewing machines.

In the bicycle world, the is technical term for this process is a beer can shim. Been keeping seatposts up since '78....

Edited December 11, 2015 by TinkerTailor