View Full Version : Tail Gears

02-04-2010, 12:02 PM
Howdy all... I've used the MA closed gearboxes for decades without problem and for the last couple of years had a open box on my Stratus. Yesterday while cruising around I started hearing a clicking sound. After landing I found the output gear on the tail had lost a tooth. It surprised me because I really was just tootling round at 1,450 rpm head speed watching the parts rotate. Yea I did some pirouetting but nothing like I've done in the past. Any ideas?

I've ordered a set of the "MA123-96 - MACHINED GEAR SET FOR OPEN CASE" ( http://www.ronlund.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=heli&Product_Code=MA123-96&Category_Code= ) These are the right gears, correct?.?. Anyone had problems with the upgraded gears? Any advice for a long life?

I got lucky with this failure and landed without incident. And at close to $50.00 for a replacement set of gears I'd like to not have to buy these too often. I'm hoping someone tells me this is a one time, maintenance free, complete fix for this in-flight failure and I can fly reasonably assured I won't loose tail drive in flight. Any help?


02-09-2010, 11:37 AM
Are those crickets chirping?

02-10-2010, 04:55 PM
I haven't seen this yet, because I'm almost only reading the electric section. I haven't had enough time on the new tailgears, but I've never had them break. So I think the new gears are a lot better so far.

02-11-2010, 09:46 AM
I've been using the new tail gears for a couple months now with no problems

02-14-2010, 08:04 PM
Only times I've had that happen is after a tail blade and the planet have kissed ; even a gentle kiss has been enough too ;);)

I usually adjust the gear mesh after 3 flights with new gears , then forget about them !!

04-30-2010, 10:22 PM
It looks like the gear got hot enough to sort of melt????? I think we have gone backwards by going to an open gear case. I don't care what kind of material you use gears need some kind of lube. Even if they run dry some kind of cover seems like a good idea to keep the crud off of them. Dirt and grit gets embedded in the gear and then all you have is sandpaper.

Brian James
05-03-2010, 07:48 AM
The Machined Gears are much stronger. Make sure the gear mesh is set with zero backlash, and re-adjust after a few flights, and you should be good to go for a long time.