Gear mesh

[kavic5150]

Having a bit of trouble getting the gear mesh just right. I've had the motor on and off a couple of times and know that it should be smoother than it is. Does anyone have any tips they would like to share?

Also has anyone had problems with 6HV gears being out of round? I did spin it and didnt see any up/down wobble but I'm not getting my face close enough to look for horizontal wobble, even without main blades on.

[sewerfly]

What works for me is to use a piece of paper on the main gear between the pinion hold the pinion against gear then tighten the motor mounts take paper out and your gear mesh should be good to go, As far as the main gear goes it might have a slight bit of play but I'm not worried about it'

[Ah Clem]

The method that Corey described above works very well and has been proven over time.

The main gears on most model helicopters are quite good, but not perfectly round. There is almost always a high spot.

Snug the motor mount bolts, not tight, but enough so that it takes a small amount of pressure to move it back and forth, and press the motor/pinion against the main gear.

Rotate the gear until you find the highs spot, and put a dot on it with a Sharpie (felt pen).

Rotate the gear around, stopping every 1/8 turn to rattle it back and forth-there should be the slightest amount of play that you can detect at the high spot (there will be a little more play everywhere else). Move the motor back and forth until you get it just right.

Tighten the motor and check it again (sometimes things move a bit when you tighten the motor).

If the mesh is still good, make sure all the screws are tight (so the motor cannot possibly move) then pull them out and re-install them one at at time, with thread lock.

I use this method on all of my model helicopters, regardless of brand.

[kavic5150]

Thanks for the replies. I'll try to see if there are any spots where the gear is tighter and go from there.

[Rob43]

Dang, RAK, that should be copy/pasted on Compass document template and leveraged as Pro Tips!

[Ah Clem]

Thanks Rob!

I did not think it worthy of that.

[Jason O'Connell]

Originally Posted by Rob43

Dang, RAK, that should be copy/pasted on Compass document template and leveraged as Pro Tips!

+100

If there is a big difference between the high and low spots then I will set it with very little backlash on the high spot then fly a few flights and recheck. The high spot is usually reduced or removed this way.

[kavic5150]

Problem solved. Thanks for all the help.

My main gear has no wobble, its perfectly round from what I can see. Gear mesh was a hair too loose is all.

I did notice that the pinion shroud (dont know the proper term for it) sits awfully close to the main gear on the right side but not on the left. I removed and reinstalled it to confirm it was not installed crooked.

[Rob43]

[sewerfly]

[LinusLarsson]

Anybody else got problems with gear stripping? I run a high powered 6hv, Scorpion 4035-560, using VBar gov. I have stripped quite a few this season. The latest I tried is to run the mesh tighter than usual, perhaps a tad to tight at the tightest spot from what would seem perfect. I also use a light oil the first few flights. This seem to have cured my problems, have been running a month without stripping.

I do not use the counter bearing, don't know if this could cause issues but it shouldn't be needed.