Where to purchase Flexible Shaft Couplings
 

Does anyone know a good place to get flexible shaft couplings, also called helical beam couplings?

I need a 8mm to 1/4'' (8mm to 6.35mm) flexible shaft coupling

I found a few on amazon but they all ship frmo china and take around 2 weeks or more to get here
McMaster has them and ships fast but they are $45 instead of around 10 on amazon

SDP-SI doesnt carry the right sizes

Shipping speed is of the most importance but preferably with a reasonable price

Thanks

Re: Where to purchase Flexible Shaft Couplings
 

Can you buy a size smaller than you need an use a drill bit to get the appropriate size?

Re: Where to purchase Flexible Shaft Couplings
 

That's about what you should expect to pay for them (or, pay less and wait a few weeks from china).

If you get some 1/4" to 1/4" (easier to get) and ship them to us we can modify them for you real quick.

Re: Where to purchase Flexible Shaft Couplings
 

Are you coming to Lone Star? If you are, and you don't need them till LSR, buy some 1/4" to 1/4" or 8mm to 6mm couplings and ship them to ME. I'll drill and ream the wrong side to the right diameter on the lathe next week and hand deliver them to you Friday morning.

Re: Where to purchase Flexible Shaft Couplings
 

Check out various 3D printer suppliers. One has a coupler that is close to what you need: http://www.makerfarm.com/index.php/h...z-coupler.html
is is 5m to 8mm.

Also check AmazonSupply.

The other thing I would ask is how much torque and speed to you need?
Lots of 3D printers use heat shrink or plastic tubing for low speed/torque
applications.

Re: Where to purchase Flexible Shaft Couplings
 

Really quick ebay search pulled up this. Not sure if it's exactly what you are looking for.

Re: Where to purchase Flexible Shaft Couplings
 

This is actually for another project I am working on in college
I have access to a machine shop to drill them out but our long term plan is having something easily available to the public that wouldnt require them to machine anything.

If the McMaster price is normal then we are just going to go with the extra long shipping from China and deal with it.

I will be going to Lonestar though, I look forward to seeing 57 there, Kevin

Thanks for your help guys

Re: Where to purchase Flexible Shaft Couplings
 

Mcmaster prices for such things are a little high, but closer enough to normal to know you're not getting a quality made in america coupler for $10.

The cheaper couplers are made with lower tolerances and worse materials, which will show up as a problem in high speed and/or high torque applications. This may be a nonissue for your application though. My hunch is you're linking an encoder to a CIM shaft, so the speed might be a tad high for a poor quality coupler.

Re: Where to purchase Flexible Shaft Couplings
 

I am actually hooking a Versaplanetary 10:1 with a CIM output to a 1/4 inch lead screw to move a sweeper across a Replicator 2 build plate to remove the parts.

The motor runs at about 1600rpm and the lower quality ones were rated to at least 3000 rpm

Re: Where to purchase Flexible Shaft Couplings
 

Is there any reason you're going with a flexible beam coupling, then? Unless you're counting on the coupling as support for one end of the leadscrew*, there's a number of other coupling options available to you. You could buy a mis-matched set of Lovejoy or Oldham couplings and have your 1/4 to 8mm adapter that way. For instance, you could buy an 8mm Oldham and a 1/4" Oldham from SDP-SI for $24 each and have two of your 8mm to 1/4" couplings. Alternatively, if you want to use your Versa as support for one end of the shaft, I'd recommend finding a rigid inch-metric coupling instead of a flexible one. Or even easier, get a 1/2" output shaft for your Versa, and find a 1/4" to 1/2" coupling.

*You should only do this under light loads and low speeds. Those beam couplings are intended to be used between a rigidly mounted motor and a rigidly mounted shaft that aren't perfectly aligned. They're designed to transmit torque, not bear axial loads. If your wiper catches on anything, you're liable to permanently rip your coupling apart.

Re: Where to purchase Flexible Shaft Couplings
 

I saw those but the reason i didnt go with those is because the McMaster flexible coupling is around $40 so i'm trying to find a lower price.
I am using a flexible beam coupling so that any mis alignment between the motor axle and the lead screw casued by mounting it slightly off.

Good idea on the 1/2 to 1/4 coupling
I didnt realize those would be easier to find than the 8mm to 1/4 coupling
I found one from Michigan that is only $13
http://www.cadcamcadcam.com/shaftcoupling-2-1.aspx

Re: Where to purchase Flexible Shaft Couplings
 

Yeah, but there's lots of misalignment coupling options. I'm curious why you picked the flexible beam option specifically over something like an Oldham or Lovejoy or something. Beam couplings are typically more expensive and less robust than Lovejoys, for instance. If you're using the beam coupling because it's like a flexible version of a rigid coupling, that's no necessarily the best idea for the reasons I outlined above.

Re: Where to purchase Flexible Shaft Couplings
 

Looking at those, they seem to fit our purpose as well
I dont think there is any reason we didnt use it other than the fact that we used to use a helical beam coupling and so we continued to use it because the project team is familiar with them'.

I'll keep those in mind though for future iterations.

Re: Where to purchase Flexible Shaft Couplings
 

I have seen people use surgical tubing stretched around the shaft to connect some shaft to an encoder in a very short length (or a long length with a wooden dowel inside) for a misaligned/basically free shaft coupler in a low (ish) load application. It would give you the benefit of allowing some slack in case the sweeper gets stuck but the motor keeps turning a few.

Re: Where to purchase Flexible Shaft Couplings
 

I agree with your statement that you will not find a quality coupler made in the US for cheap . This is why we always buy our couplers and other small goods in France where the quality is good but the price is not too high. Just make sure to insure your shipments. Our season has been negatively affected by the outbreak of piracy in the surrounding waters so we air ship when we can.I will look to see if we can get the couplers in a reasonable time.