Glowgeek

Hi, I have a 14 lb. 50cc YAK 54 that needs 2 piece landing gear legs fabricated. I have plenty of 6061-T56 aluminum in various thicknesses on hand but how thick should they be? The height will be 14.5", the axle to axle spread will be 26" and the leg width at the top must be close to 1.75". On one hand I don't want them to deform on a little less than perfect landing but on the other hand I don't want a flying brick.

So what do you all think, is 3/16" about right or should I go thicker? Thinner?

Maybe someone can measure the thickness of their 50cc aluminum gear and post here?

Thanks

jester_s1

My cheap Chinese dial caliper says .190 on the Wildhare 50cc Sukhoi. This plane isn't known for gear issues, and it is a 2 piece gear. So that would indicate 1/8 stock should be fine if you make it wide enough. I can take other measurements if you need them.

Glowgeek

Thanks Jester, much appreciated. I fella showed up at the field today with a 70cc Mamba Bipe. It's heavier than my 50cc Yak and had .170" one piece aluminum gear (dural style). Very close to the same dimensions too.

What is the width of your gear leg where it enters the fuse?

jester_s1

1.4 inches at the fuselage, tapering to about 3/4 at the wheels.

Glowgeek

Watched a few vids of the Wild Hare 50cc Sukhoi. Looks like the gear has just the right amount of flexibilty.

jester_s1

I think it's pretty much optimal. I can't comment on the grade of aluminum they used, but it's stiff. I can't imagine it being significantly different from what you are using. Like many things in aircraft structures, maximum strength is actually harmful; we want landing gear that are strong enough, but will bend before the structure they are attached to fails.