8mm to 8mm Bore Rigid Coupling Set Screw L22XD14 Stainless Steel,Shaft Coupler Connector for 3D Printers, Motor Accessories,2pcs

I figured that I would give this a shot to join a 1/4 to 3/8 inch shaft for a drill. 3/8 is about half a millimeter smaller than the 10mm spec but I managed to get it set just fine. After a few tests I noticed a slight wobble. This was quickly resolved with a thin shim to steady and center the 3/8 in shaft in the 10mm hole. Precision demands such things. Now I know how tolerances are important if you want a quality tool. I’m really happy with how it turned out. Good coupling sleeve for mating two odd shafts. If I need another one in the future, I wouldn’t hesitate to order more of the same. Highly recommended.

Yep, I said "Almost". But it's my shortcomings not the product's shortcomings that make me say "almost". The set screws are really small and hard to see or insert. You have to put them in the right way or you cannot use an allen wrench to tighten them. In my younger days, before cataracts, I wouldn't have had any problem seeing these set screws. But today, it was difficult getting them screwed in and tightened. I would have liked the set screws to be locked into the holes so I only had to tighten them and couldn't take them out or lose them. I am building a linear stage which uses a 5/16" threaded rod and a 12VDC motor with a 4mm shaft. I needed to connect them together. I talked with employees at the big box hardware stores and department stores -- they had no idea what to use to make the connection. It wasn't until I realized that the motor manufacturer would probably have good ideas for how to make the connection that I found these connectors.

Seems well made and finished. Worked well for me.

I bought these for my Halloween yard decoration. They held up pretty good. I did have to tighten the little screws every so often, but they held up. The accuracy of the measurement is spot on. They are very easy to use and you dont have to torque them down to much. I would recommend using locktight with these.

Great couplings. I need them for a DIY project and I could not find anywhere except on Amazon. They fit perfect on the 8mm rod.

Excellent Product, Excellent Quality, Excellent value for the money.

Honestly it would be hard not to make a good set of shaft couplers like these. They work great, and will probably be reusable forever unless you make the mistake of stripping the threads somehow. The set screws (grub screws) included could be a mm or more longer depending on how you use the part, but if you are coupling shafts that fill the holes entirely then they will work just fine. In my case I was trying to grip a shaft that was undersized and this was the closest coupler I could find for my application.

I can’t describe how frustrated I am with almost all couplers on Amazon. Unless you are using this for something extremely light duty it will not work. I was attempting to use this as a very very small drive shaft as the torque from the motor and system were in range, but the set screw could not be torqued tight enough to prevent backing out due to vibrations. Instead it would strip leaving you needing to drill out the coupler instead. This coupler took years off my life, buy a reputable one from McMaster so you can buy once cry once instead of trying thousands of options

Worked as intended

Worked perfect to connect two ends in a stereo amplifier I was trying to fix.

Qualité!

Using this to connect a motor to a bike trainer to create a generator. Seems OK so far but needs to be aligned correctly. I have a flexible one on order just in case.

Works great from round shaft to hex