SDP-SI Module 1.0 SS Pinions
 

I bought some SS Mod 1 pinions last week and got them in the mail today. Is it just me, or do they have a REALLY SMALL set screw in them? I don't even have an allen key small enough! I might try and drill them out and tap it for a 4-40 set screw; or do you think grinding a flat in the motor shaft will be enough? I know some of you have bought these pinions before. Have you had any trouble with them spinning on the shaft? Seriously, who thought it was a good idea to use a 1.5mm (diameter) set screw in a Mod 1 gear? Does anyone even make a 0.5mm allen key? :no:

Thoughts, anyone?

Yeah, I think it'll be fine as long as you have that flat spot. The only downside to smaller grub screws IMO is that the hex driver to loosen/tighten them is smaller and may tend to strip out easier if you use red lock-tite or really torque down on the grub screw.

Thanks for the reply, Brian. I'm definitely gonna use some thread-locker. Do you know what size set screw Mike uses in his Mod 1 gears? I would really prefer to have some with a larger screw because I am afraid I'll strip these and/or just break the allen key (once I find one to fit).

I would just drill it out and re-tap if you can...really not worth it to use a micro sized set screw when the whole point of having Mod1 pinions is to hold up to the power...

IIRC, the ones I have from Mike use 3mm hex wrenches...

You took 'em right out of my mouth. :yes: I'd like them back... :mdr:

3mm sounds much better, Brian. I'll have to pick up a few from RC-M. They really couldn't be worse, ya know?

Yup, Brians right. There 3mm.

I could be wrong but I thought they were 2mm.

Hmm, well, they're either 2.5mm or 3mm since those are the only wrenches I have. :smile:

Mine use 2mm hex, and some of my smaller ones (before he went to all hardened gears) use a 1.5mm hex.

Can you drill and tap stainless steel gears? Most stainless that I've run across is pretty brittle.

thats what I thought.

Just rechecked my pinions. My older ones (the silver non hardened ones) that are 15t and under have a 3mm grub screw with a 1.5mm hex.
My carbon steel 16t and 20t pinions use a 4mm grub screw with a 2mm hex.
And the newer hardened steel ones which I received yesterday also have a 4mm screw with a 2mm hex. Mine are 17t and up, so I'm not sure if the smaller ones use a 4mm or a 3mm.

I have a couple 20t mod1 5mm bore pinions from Mike, the most recent one being from maybe 4-5 months ago. Both use 4mm set screws, which are driven by a 2mm hex driver.