i can see a double blade disk after a rebuild

[Snake_uk]

after a fairly low speed tip over on my blade 450 i needed to replace the following:

1 x pair of blades, they hadn't snapped but the plastic covering had come off the ends
1 x main gear, how the hell you screw the one way bearing in square is beyond me, the gear is running up and down the drive pinion by about 3mm
1 x tail boom

anyway after the rebuild i spooled it up in the back garden and i can see 2 disks when the blade spins (seperated by about 10mm) if that makes sense,

so i assumed that the feathering spindle was bent as well, i've just replaced that but its too dark to try it.

am i barking up the wrong tree or could the blades be warped, or the main shaft be bent (though it did look and roll ok along a flat surface)

i need to join a heli-club

[challis349]

If it's still out now, all it will want is setting up again with the links, it's due to there being one blade higher than the other, it's called blade tracking

[Snake_uk]

at least i know what to search for now

[Made2Fade]

adjust your blade tracking as Kev has suggested...
what heli is it? Need more info

[Snake_uk]

adjust your blade tracking as Kev has suggested...
what heli is it? Need more info

its a blade 450, im just watching you-tube tutorials on blade tracking, looks easy enough know i know what its called

[heliward0]

feathering shaft is bent mate..

[Made2Fade]

well if you find you adjust and no matter what you cant get them to track straight then you have a bent feathering shaft (the shaft that goes through the 2 main blades grips and mast).

[Snake_uk]

ok an update,

i test flew it after fitting a new feather shaft, no change, tracking was still out so i followed a you-tube tutorial and stuck a piece of black tape on one blade so that i could see which blade was high. Went to adjust the links and the ones i was going to adjust were solid links with no adjustment

so i changed the only part that i hadn't replaced and that was the main shaft, test hovered it and its bang on now

im going to take the old shaft into work tomorrow and get a turner to stick it in his lathe just to see how much it had bent, it looked ok on first inspection.

so it looks like i can never track the blades on this helicopter

thanks for all your input

[Made2Fade]

adjusting the long link that goes from the swashplate up will do your tracking. That one is adjustable the others are fixed. All collective pitch helicopters need to have adjustments for tracking

[sacko]

Instead of using black tape etc, just get each blade a 0 degrees pitch at mid stick.

If changing the pitch in each blade doesn't work, try a decnt set of blades if you haven't got some already.

[challis349]

Also I just put a little dot with permanent marker on the root of the blade, as any tape on a balanced set if blades will mage them out if balance, and then possibly cause the same issue

[Snake_uk]

Another update:

just put the old main shaft in a lathe and its running true, no bends whatsoever, so i dont know how the blades managed sorted themselves out

[nicobec]

Roll the shaft on a hard surface like glass. If it lifts on one side it is bent.

[bikerflier]

i need to join a heli-club

Try Midland Helicopter Club, near Twycross Zoo. Some top class fliers there and all the help you need.

Midland Helicopter Club website - Home