I Need Tail rotor help on Heli Max mx450

[pilotx]

The tail blade pitch control sticks badly, won't slide smoothly when giving rudder input. Replaced the shaft and plastic spacers, still sticks badly. Broke the plastic piece connecting the pushrod to the piece that slides on the shaft (name???) because of so much pressure. Should slide smoothly! Suggestions? I am not lubing the shaft per advice from hobby shop. I tried to smooth out the brass bushing that slides over the shaft with 400 grit sandpaper. Does not slide smoothly. HELP!!! I want to fly, not fight this infernal tail!!! :arggg:

[ChrisLaFollette]

The brass thing that slides over the shaft isnt smooth? There is your problem. Wrap some sandpaper around a drill bit and polish the inside of the brass piece and the output shaft a little at a time until they both slide smoothly. Then use a DROP of lightweight oil on there when its all together and sliding smoothly, Triflow preferably but 3n1 works also as I have used it before with no problems when I couldnt find my Tri-Flow. I would stay away from WD40 and stuff like that though. You have to eliminate the problem by going piece by piece and ensuring all is well until it works like it should. Do NOT fly it with the tail sticking like that as you could possibly crash if the tail isnt holding and could burn out your servo very quickly.

[pilotx]

The brass fitting that slides over the shaft IS smooth on its inner surface, but it doesn't slide smoothly over the shaft. Jerky and catchy. With or without the linkages hooked up. Shouldn't it slide as smooth as butter over the shaft? Thanks for your advice. I am wondering if I should replace the whole tail section, but there is a brand new one put together at my local hobby shop and it sticks too!

I will try boring the brass fitting out and making sure it is glass smooth, and try a drop of tri-flow. Not sure what else to do.

[Raven_darkcloud]

That part sould be perfectly smooth. You may have a bent shaft. The trex steal ones work great on the 400s so sould also fit the 450 as the only differance is the preinstalled upgreads and extended tail. I use them with the trex pully and it works good. Look for any side play in the pitch slider as you turn the main blades. The wobble can be small so look hard and spin the main blades slow so you can see it.

[xcellrc]

My MX450 had a sticky tail pitch slider also. I'm not sure about yours, but the tail output shaft on mine had a black oxide finish (like a typical hardened bolt) on it that caused most of the problems. I knocked the coating off with some 600 grit wet or dry sandpaper (wet). After that I polished it smooth with 1000, then 2000 grit wet or dry sandpaper. I also used a little metal polish on it to get it mirror smooth. The tail pitch slider moves easily now, even better with a drop of a graphite bearing light oil. The polishing might not be necessary, but its worked great for me. Typically I don't oil the output shaft of nitro helis, but this oil is extremely light, and has caused no problems so far.

[ChrisLaFollette]

Pilotx,

I know that the brass slider is smooth but it is probably slightly undersize therefor making it stick up on the shaft, it could also be bent/slightly ovaled on one side therefor making it catch up. Do what I said and sand the inside with some 400-600 until it slides pretty smooth and then put some 1000 in there and smooth it out and then apply a drop of tri-flow and be done with it as long as its smooth.

[pilotx]

Thank you all for your help. I polished the shaft smooth and put a drop of oil on it. I also replace the slider. Works much better so far, proof will be tonight when I fly it. Thanks again for the help!