Z-Axis - Measuring Shaft Coupler size?

Long time lurker, first time poster. I just put in my order for my maslow kit and am looking to add the Z-Axis kit as well. I have a Craftsman router (this one: https://goo.gl/3iEs4u). It is very similar to the recommended Rigid router, so I am going to give it a try.

I’ve removed the adjusting knob exposing the shaft (picture below), but I’m not sure what size coupler to order. Measuring from flat side to flat side it is 1/4 inches, but curved side to curved side it is 5/16 inches. Anyone know what size I should order? I’m very new to this, so I appreciate any help.

Thanks so much!




The shaft coupler has a round opening which will fit over the entire end of the shaft so I believe that 5/16ths inches is the shaft coupler you want. That type of shaft end where there are flat and round sides is pretty common among routers and we haven’t seen issues with them so I wouldn’t worry too much about it being different than what you might have been expecting

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Perfect. Thank you!!

The coupler that came with my Maslow Z-axis doesn’t fit my Ridgid router. Do you know the coupler size for the Ridgid router, and the Z-axis motor?

Thanks in advance.

The shaft is 6mm and the rigid shaft is 3/8" so it can be a tough shaft coupler to find.

If we sent you the wrong one email us at info@maslowcnc.com and we’ll send you the right one free right away!

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You sent exactly what I ordered :slight_smile: I didn’t know at the time so I just picked a size. I have the recommended Ridgid router and I will be glad to purchase and pay for shipping. Thanks again!

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Great! Shoot us an email and we’ll get you the right size!

I have found an 8mm kit online, which router would this fit if any? And/Or I am trying to make a z axis motor since the kits are out in your store. Any suggestions or links for me to find everything I need.

Thank you

Better to find a suitable router, measure both the motor and router shafts, then pick the coupler. Cart/horse.

Available routers in Estonia will be different than those in New Zealand or Mooseville

For anyone with a 3d printer I made a solid coupler for my ridgid router.



There’s a plethora of connector designs on thingiverse too, some configurable

I didn’t see one that would press fit the d shaft of the motor and the slot of the ridgid router when I went looking. Sorry to duplicate effort.

Any additional help figuring this measurement process out? I need to buy the Z-Axis kit, but have no idea what to measure to obtain the final numbers for ordering the kit. I purchased this Ryobi router

Any help would be greatly appreciated guys!


Not sure if these really answer that but might be useful…

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Right on man! Thank you! The first one you listed I think clears up my question as to which Z-Axis kit to order. As for how to measure for the coupler, I guess I’ll just have to figure it out once everything arrives!

Thanks again KingOfScolboa!

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