some wear measurement quantities

[macem]

hi all,

i replaced the blade-grip bearrings (both axial and radial) for the first time, and found the axial one nearly flatted (!) , one radial broken.

so flying the mini about 70 hours (1000 flights) raises the question about mechanical wear of the mini? (whitout consequences of crashes of course...)

i know somewhat about motor pinions, belt, servos... but do you have some experiencies ?

macem

[desertstalker]

Bearings and belt would be my major concerns (including the one-way in the pinion) check all of them for wear (especially the ones in the guide pulleys).

[ziper_it]

I can count more than 800 flights, and only had to replace the axial after crashes, thrust being still good.

The weakest are the ones on the tail, as the slightest touch may destroy them.

[kjoer]

1000 flights is massive! I'd expect the thing to drop out of the sky without thorough maintenance, but I guess it didn't.


Over 300 flights here, no crashes yet.

Belt and pinion are completely toast, replaced them, waited too long with it though, should have prolly changed them after around 150 flights.

I've changed the tail blade grip bearings a few times. Other than that, nothing. Oh, the dampers, but they were still ok.

[ziper_it]

Dampers, I forgot about them. Changed two or three times. Belt I probably would have had to replace it if it wouldn't have been damaged in a crash.

[baui2000]

Dampers get changed every crash on mine. Other than that...stretch belt shows no signs of wear with some 300 flights and couple major crashes on it, pulley bearings all good, 15T one-way is ok.
Radial and thrust bearings in blade grips get replaced after each crash.

The only thing I change as a precaution are motor bearings, all my Scorpions get sealed high quality ones right out of the box.

[kjoer]

Didn't use silicone spray on my first belt, might explain the wear.

[macem]

thanks a lot ... so i have some more open items on my check-list

for most of us the motor pinions seem to be the most critical parts (replace after 150 - 300 flights), followed by the tailrotor-bearrings, dampers and belt (although esp the dampers seemed to me undestructible... )

furthermore i found the endurance of the servos (i tested hs65hb, savoxsh0254, align ds410) very similar by 400 flights on average, the old motor adapter by 500 flights (the special shaft will keep much longer...) - and now the bladegrip-bearrings by 1000 flights... but it should be replaced a little bit before, i guess

macem

[baui2000]

Almost forgot servos... SH-0257MG on FBL cyclics developed noticeable slop in about 150 flights, all three of them at pretty much the same time.

[kjoer]

Same with my MKS DS95's and DS95i, a bit of slop after 300 flights. No idea how their wear compares to other servos though.

[ziper_it]

Already replaced one pinion and half (the second was still usable but I wanted to try the 17T).
Lot of slop on 5065 compared to the same servos mounted on my other old, non-FBL 450. May it be due to the higher stress from the FBL system?

[th0rg0d]

Originally Posted by kjoer

Didn't use silicone spray on my first belt, might explain the wear.

I have some silicone spray, how many flights should I be applying it?

[kjoer]

I have no idea about the interval, am rebuilding the Mini Protos right now with a new belt, sprayed with silicone. You can see the difference when a belt is completely dry or not though.

(Doesn't seem critical for this heli. With a brand-new Gobler, if you don't use silicone spray on the initial build, the main motor belt starts protesting after 20 runs. You can hear it there, made me start to use silicone spray.)