Landing Gear

Howdy,

I have never built an airplane with dural or carbon fiber landing gear and was wondering how you put the wheels on. I know you can buy the axles from Great Planes but I have also heard you can use a 4-40 bolt to do the same thing. Any help will be appreciated.

LAST EDITED ON Aug-15-03 AT 11:28 AM (CDT)
 
Use a 4-40 bolt,or screw and some washers through a section of brass tubing used as a bushing in the wheel. I also use lock nuts to secure the whole assembly to the landing gear.

You can also use 5-40 bolts. They fit most wheels without needing a brass sleeve on the bolts. They are a little hard to find but Micro-Fasteners in NJ has them.

I second the motion on 4-40 bolts. Do use the brass tubing that fits over the bolts. If it is too small for the wheels, then bush the wheels with the next size up (and the next if needed). If it is too tight for the wheels, bore the wheels out.

The advantage of the brass tube is you make it a little larger than the width of the wheel and, with washers on the outside, lock it to the gear and it becomes the axle. You can double nut the bolt, and even use this method for wheel pants. Make the brass tube again just a little wider than the wheel and make the wheel pant that exact size inside. Then the brass tube becomes the axle and you can run the bolt all the way through the wheel pant, and tighten it down. Use thin plywood on the inside of the wheel pant and a washer to keep it from crushing.

LAST EDITED ON Aug-16-03 AT 01:48 PM (CDT)
 
I have been using 5-40 button head (socket head) machine screws with a "grip" long enough for the wheels used. Two elastic lock nuts and two #4 flat washers per axle and trim off the excess thread with a Dremel and abrasive disc. The washers are on each side of the wheel hub, and the nuts are on each side of the LG leg. The button head is a very svelt roundhead, so looks good from the wheel side. Works good, and is tough. Also, I asked Howard if his famous landing at the NATS broke his CF gear with epoxied-in axles. He said they didn't break or cause any problem. I think the axles are CF tubes. Steve