Gear Mesh - Motor

[ridgehead44]

Hey all!

I've never had problems setting gear mesh with my motors before. That said, I've never tried to set the gear mesh for a 6S rig. Before tonight, it's just been 3 and 4S cars. First I tried to go by feel, but then that bound up the transmission too tight for the motor to even run. Then I tried the paper slip trick. Here are the results:

It sounds...wrong? I'm trying to set the mesh on a 19t pinion with a HW Max6 system. Maybe it's supposed to sound like that? Again, this is the biggest motor/pinion combo I've ever worked on, so I'm not entirely sure.

Any advice ya'll can offer is super appreciated. Thank you!

 

[WickedFog]

Hey all!

I've never had problems setting gear mesh with my motors before. That said, I've never tried to set the gear mesh for a 6S rig. Before tonight, it's just been 3 and 4S cars. First I tried to go by feel, but then that bound up the transmission too tight for the motor to even run. Then I tried the paper slip trick. Here are the results:

It sounds...wrong? I'm trying to set the mesh on a 19t pinion with a HW Max6 system. Maybe it's supposed to sound like that? Again, this is the biggest motor/pinion combo I've ever worked on, so I'm not entirely sure.

Any advice ya'll can offer is super appreciated. Thank you!

That sounds about right.

What I do is snug the bolts as close as I can and still be able to move the motor. Abiut 1/4 to 1/2 turn from pretty snug. You don't want to set your mesh with the motor not sitting perfectly flush against the motor plate.

Then I check the movement in the spur. If I can rock it and "just" see it move just a tad while the pinion stays still, I give each screw a very small turn to tighten just a bit more. Then I check again. I also check the spur in like 4 spots to check for runnout.

If the mesh is still OK, I snug each screw a bit more. Check again, then tighten back and forth between the screws til it's fully torqued down. Then I check again

 

[Greywolf74]

That sounds about right.

What I do is snug the bolts as close as I can and still be able to move the motor. Abiut 1/4 to 1/2 turn from pretty snug. You don't want to set your mesh with the motor not sitting perfectly flush against the motor plate.

Then I check the movement in the spur. If I can rock it and "just" see it move just a tad while the pinion stays still, I give each screw a very small turn to tighten just a bit more. Then I check again. I also check the spur in like 4 spots to check for runnout.

If the mesh is still OK, I snug each screw a bit more. Check again, then tighten back and forth between the screws til it's fully torqued down. Then I check again

This is basically the same thing that I do too. Setting the mesh is the same regardless of whether its a 2S rig or a 12S rig.

 

[ahr43]

+1 and +1 to the above.

ridgehead, you didn't mention if perhaps you were transitioning from a 48pitch to 32pitch gearing? Meshed, they sound all together different. Thinking its perhaps the more coarse gear count/ratio that 32p gives over 48p. To my old ears, 32p sounds 'clacky' and 48p sounds 'clicky'.

I set pitch on my RCs by sound as much as by feel. Again, either way, check mesh sound, feel or gap at multiple rotation locations of the spur.

My 2cents. Hope this helps. -AC

 

[ridgehead44]

Ugh. Tried and failed. Killed two pinion gears just testing on the bench. I am not good at this hobby, lol.

 

[ahr43]

Ugh. Tried and failed. Killed two pinion gears just testing on the bench. I am not good at this hobby, lol.

Hmm. That's unusual, ridgehead. First of all, don't give up. Enough brainpower on this forum to help you resolve this. You're better than you think you are.

O.K., what exactly failed on the pinions? Pinion teeth, bore, grub screw? Tried running the motor with a pinion in place but not engaging the spur? Maybe the motor shaft is not running true or is bent or has bad bearings? Motor mount square to the chassis so pinion engages the spur uniformly? Rotate a set of wheels manually with the pinion/spur engaged to feel if there is a bind anywhere. Center diff mounting the spur square to the chassis? It has good bearings?

Process of elimination. Something is definitely amiss. Buck up, mate. Hope this helps get you back on track again. Sure some of the other guys have a few suggestions as well. Cheers. -AC

 

[largaines]

I would double check the pitch, many moons ago I had one come labeled wrong and pretty much had the same issue. Sounded like a blender chewing ice until it chewed the teeth off

 

[CertifiedMike]

Gears are tricky.
You need yo make sure the gears you are trying to use are compatible. They need to give you the right gear ratio, they need to fit and then they need to be installed and set correctly...
Its not you.

 

[ridgehead44]

Thanks everyone! You're all very kind.

Yeah, so the grub screw came undone when I ran the motor. I did this twice Next time I'll use an Allen wrench to get an extra half turn or so on the grub screw and give the thread lock time to set overnight before I do any testing.

Thanks again, y'all!

 

[WickedFog]

Thanks everyone! You're all very kind.

Yeah, so the grub screw came undone when I ran the motor. I did this twice Next time I'll use an Allen wrench to get an extra half turn or so on the grub screw and give the thread lock time to set overnight before I do any testing.

Thanks again, y'all!

Try adding the loctite to the grub and let it set up, then install it.

@Littlemotor uses Loctite 248, which is a paste. I've never had a problem with either 242 or 243, but he says 248 holds better, so maybe try that.

 

[Greywolf74]

Try adding the loctite to the grub and let it set up, then install it.

@Littlemotor uses Loctite 248, which is a paste. I've never had a problem with either 242 or 243, but he says 248 holds better, so maybe try that.

This! And let it cure overnight.

 

[RustyUs]

Thanks everyone! You're all very kind.

Yeah, so the grub screw came undone when I ran the motor. I did this twice Next time I'll use an Allen wrench to get an extra half turn or so on the grub screw and give the thread lock time to set overnight before I do any testing.

Thanks again, y'all!

I'm sure you already know, but make sure pinion gear and set/grub screw threads are clean. I

From 2s to 6S platforms... 48P to MOD1... from 2wd to 4wd... basically how I check if mesh is great:

 

[ahr43]

ridgehead, looks like you are running steel on steel pinion/spur.

Many times steel pinions come new out of the bag with machining burrs still present. They feel and in fact are rough. As a matter of course I do a quick polish on steel pinions before an install. Grub the pinion on to a piece of rod stock and chuck it up in the drill press turning medium speed. Polish it using valve lapping compound - first coarse; followed by thin. Use a wire brush chucked up in a dremel to polish the teeth while the gear is spinning in the drill press. (Note: wear a face shield while doing this!)

Result is a baby-skin smooth gear tooth surface free of burrs. Makes for a super-reliable mesh setting. -AC