[SSN Vet]

I need a coupling for a ball screw with a 12 mm dia. end and a stepper motor with a 1/4" shaft. It needs to be at least 1" long, preferably a little longer.

I'd prefer an economical helical coupling with a clamp action vs. a set screw.

I'm having a tough time finding one that can mate these two shaft sizes.

Thanks for any help.

[Andre' B]

Have you given these guys a call?
http://heli-cal.com/cm/Products/Flex...ings/Home.html

[SSN Vet]

thanks for the link...

they don't have the 12mm / 1/4" size listed that I can see.

but I sent them an e-mail just the same.

[Al_The_Man]

Try Misumi USA they have different couplers that offer those shaft sizes, you will need to look for 6.35mm to 12mm, not 1/4"x12mm.
Do not get a helical aluminum for driving a ball screw, S.S. is the best, but Misumi offer other zero backlash styles such as Oldham etc.
Al.

[Andre' B]

If you pick say the MC Series and go to the bottom of the page it shows how to build a part number for custom sizes.
http://heli-cal.com/cm/Products/Flex...MC-Series.html
Note that they are probably not the cheapest place to get these couplers but unless I am mistaken they first developed them.

[TXFred]

McMaster Carr has a good selection. I'm very pleased with the aluminum couplings that I got from there.

http://www.mcmaster.com/#helical-beam-couplings/=8l4dfq

They offer metric to inch couplings, but not in the size combination you need.

My best advice is to get something that will fit one shaft and can be drilled or bored out to fir the other shaft as well.

Fred

[thumper650]

You might try http://www.dumpstercnc.com/. I have talked to him before on making me custom lead screw nuts.
He has the clamp on style clamps instead of setscrew. Steve

[SSN Vet]

case closed....

Michael at CNC Fusion has hooked me up and at a very fair price. Exchanged a couple e-mails, executed order on his web site with special note in paypal note to vendor block.... Done!

I started with McMaster, but saw no provision to do one side metric and the other Imperial units. I use them all the time at work, but if you need something special that's not verbatum from their catalog, it's kind of a pain to deal with them.

Heli-Cal responded to my e-mail with the exact coupling I wanted... but when I replied that I only needed one, they stopped talking to me