Best method to set spur gear mesh

[Huggybear87]

What's everyone's opinion on the best method to set spur gear mesh? I tried the paper method but that didn't really work for me, I ended up just going by ear I must've gotten it right or pretty close because I haven't destroyed the gear... Yet

 

[HPIguy]

This is the tried and true method;

1. Loosen up your motor mount screws, not sloppy loose, just loose enough where you can move the engine with a bit of pressure.
2. Take a sheet of notebook paper, cut a strip about 1/4" wide, fold it in half and feed it through between the pinion / spur or clutch bell / spur.
3. With the paper wedged in there, tighten your bolts back up.
4. Remove the paper and rotate everything by hand, you shouldn't feel any binding anywhere. There might be a tighter spot in one place on the spur, plastic spurs are never completely true in my experience, but that won't hurt anything.
5. If it all checks out, go have fun!

With time, you'll just get a feel for it, and be able to just set it by eye / hand and be good to go. What you don't want is too loose or it generates heat and wears the gears down prematurely, or too loose and it shells out teeth.

 

[Rolex]

You need to make sure you are holding the engine absolutely square to the spur so you get the mesh set evenly across the teeth.

 

[moe7404]

if this is to far off please forgive me. back in 60s i helped build dragsters. we only had stock rear ends. trying to hold 1,000-1,300 HP what we did was set the pinion and ring gear quite a bit tight. so when the power comes on the gears and housing flex and gears are alined up just right. and the gears would make a sound when you towed the car. just something that came to mind.

 

[Rolex]

When our RC cars put out 1000 HP or better, we'll try that.
Until then, the paper is almost 100% perfect.

 

[goodgamer]

I have always looked and listened. If I think everything is fine I run it a bit and listen (if it's electric, kinda hard to listen on a nitro), check all the screws again to see if they are tight then I am on my way. It a has always worked for me since day one. Hopefully it will still work knock on wood!

 

[Nitro Nerd]

I learned simply by feeling and hearing that "tick". The smallest play you can get while still having play, AND it's smooth. Paper trick does not properly teach someone how to set it by sight/sound/feel.

 

[2revo1maxx]

^^^That's it right there, The best way.

 

[frickenjoey]

That is how I do it now. When I was a noob I used the paper trick. But once you have felt it the right way so many time you can then do it without the paper just by feeling the right amount of play in the bell/spur. I would use the paper method until you get the hang of it then take off the training wheels.

 

[ozziii]

Making sure you have good light to see properly is a big help & using a good small flash light or torch to shine onto the teeth can make it easier to see if they are aligned properly.
Like stated above, a very small amount of play is all thats needed, I do mine so when I hold the spur I can move the clutchbell a very small amount & I make sure the teeth are as straight as possible to each other. Normally of they are to tight you can hear a slight winding noise, even on a nitro, if to looses then a chattering sound.
With a nitro you can just push the car along the floor/ground & listen to see if its making a noise then re-adjust if needed.

 

[Nitro Nerd]

Making sure you have good light to see properly is a big help & using a good small flash light or torch to shine onto the teeth can make it easier to see if they are aligned properly."

Yes. For some vehicles (like Mugen) where where everything is a tight fit, just remove the fuel tank. This will give you all the access you need. Most important...don't forget to thread lock once you've got the mesh set.

Curious if any of you have quick change mounts that save you from having to reset your mesh (like my D8T in the attached pic). I remove/install my engines a lot but have never used it. I'm sure it's handy, and will try it one day.

 

[ozziii]

Yeah I run a JQ Products THE Car & its a pretty narrow chassis so everything is very tight so removing the tank always helps, it has the dual mounts as well but I normally just remove the lot anyway, mainly because I don't have the ball end hex drives & the normal hex drives don't quite fit properly but I'm pretty fussy when it comes to the mesh anyway so don't mind re-aligning it, it doesn't take much once you get the hang of it.

 

[jose.28]

Its not relly hard at all to set it in the first place. Its more of common sense.

 

[Cornholio]

Its not relly hard at all to set it in the first place. Its more of common sense.

I agree. I've never used the paper trick or whatever. Just align it straight with a tiny gap and you're good to go.

 

[ozziii]

Yeah as long as its straight & only has a small amount of movement then its fine, if it makes a noise when driving then that normally means there is a problem.

 

[Nitro Nerd]

Just remember, it's all a moot point if you don't thread lock! ;-)

 

[Huggybear87]

Just remember, it's all a moot point if you don't thread lock! ;-)

Very good point

 

[2revo1maxx]

I never use thread lock on rc stuff.

 

[Nitro Nerd]

I never use thread lock on rc stuff.

Wow. The few times I've ever forgotten to thread lock any metal against metal, I found out about it pretty quickly. ;-)

How are you able to keep things intact without thread lock?

 

[maddmike]

I would like to know too I always loose screws when I dont use loktight