Trex lubrication

[Caravan9927]

Yes Folks, its me again with yet another question.

I note that some of you lubricate the tail belt with a silicone spray ( see Noob Threadlock and Belt Question below ) What about lubrication of other moving parts of the Trex namely the plastic main gear, tail drive gear, main mast and rudder spindle ?

Most of my fellow club members are against it because they say it tends to collect dust and dirt from the ground on start up but I would have thought some lubrication would be essential, especially the main gear where it wears against the motor pinion. The manual offers no guidance so any views on this would be gratefully received.

[SRH990]

The main gear is plastic and is self lubricating, greasing or oiling it will actually make it wear faster. I do use a drop of Triflow oil occasionally on the tailshaft/pitch slider and on the mainshaft for the washout mixer block, I don't lubricate anything else.

[Caravan9927]

Thanks Steve. Although I have read or heard of this before, I have never really understood the reasoning behind why plastic should be self lubricating. I am not doubting your word but I have never seen anything in print from any of the heli manufacturers or build guides to say that plastic main gears are self lubricating and my suspicious nature makes me wonder if this is not simply a myth passed on by fellow fliers but without substance. If you could show me a link or something that would confirm this, it would help squash a niggling doubt I have on the subject.

Regards

Bernie

[DemonJim]

I haven't got any links, but have personal experience and reasoning to help convince you that the main gear should be ungreased.

I would say it's not so much that the plastic self-lubricates, it's that there is less resistance when the plastic gears are clean and free to mesh together without having to constantly displace grease.

Not knowing any better, I lubricated the main gear on my old Twister 3D once, and was amazed how much power I had lost. The teeth aren't actually sliding against each other so much as making and breaking contact. The oil's viscosity actually increased drag in this rapid meshing and releasing wasting power from the motor. As the motor pinion runs so fast it's better to leave it free from obstruction, and as there's so little actual friction anyway the gear lasts ages without any lubrication.

Also lubricating the gears attracts dirt, and this grit will wear the gear out a lot quicker than clean dry teeth.

Or something

[Caravan9927]

Many thanks DemonJim. What you say makes sense and bearing in mind Align as well as Hirobo and Thunder Tiger, don't mention lubrication of the main gear, I assume they must have a good reason for not doing so. All I needed was a practical reason for not lubricating them which you have provided, so many thanks.

Bernie

[SRH990]

You will find that if you lubricate a main gear, it will flick off when the heli is running and cover everything with sticky s**t

I can't point you in the direction of anything that says unequivocally that you shouldn't lubricate the main gear but I've never done it in 20 years nor seen it done. I've put a few hundred flights on my Trex 600N and there's no noticable wear, the only time I've replaced a maingear is after a crash. The point DemonJim makes about grease or oil attracting dust and grit is very valid and will lead to increased wear. The only time I lubricate part of the drive train is to use silicone oil on tail drive belts as this does reduce drag and helps combat static.

[ShinOBIWAN]

Not an Align but Raptor 90SE, I figure this talk is pretty universal for all heli's.

I don't lubricate the main gear etc. but I do put a very thin smear of Triflow on each end of the torque tube, as without it tends to rumble and seems slightly notchy. This isn't exposed to any dirt though since its sealed in the tail boom.

I bet a few folks have seen the finless build video's on here, I can't say as I ever remember him greasing the gears during his numerous builds and the guy knows what he's doing.

[Caravan9927]

Thanks all of you for putting my mind at ease on this. It was just that my logic said I ought to lubricate any part subject to friction but bearing in mind how cheap the Trex main gears are I suppose it doesn't really matter either way. However, I take your point about dirt and oil contaminating the rest of the Trex and will restrict lubrication to the rudder spindle.

Bernie

[supafastsupra2]

the lubrication of the tail belt is mainly to reduce chance of static discharge and possible brown outs/ signal loss

[shaun.e]

Check out Finless Bob's advice on maintenance on the Heliguy.com website. I use an oil pen which allows a small drop of watch oil to be placed with the needle. I sparingly lube the washout block/main shaft area, see-saw bearings, tail slider for each flying session.