Just bought a beautiful RTF Extra 300 from another flier at my field. Flew it first 2 flights today. The wheel pants are held on by a "wheel collar" type fitting with 2 screws through the wheel pants on one side and the pants are already cracking and not on firm or tight.

What are the best products, gadgets and techniques to secure the pants well so they don't move, crack, or fall off?

I had previously taken off all the wheel pants on my other planes since our field is grass but this Extra is big enough that the wheels should clear the grass without much trouble but a rough landing might do a job on them the way they are secured now.

Thanks!

I like to use 4-40 bolts and T-nuts, all you need is a plywood plate inside your wheel pant for the T-nuts to sit in and your bolts go through the landing gear and into the T-nuts. It's really a strong setup, just make sure that your bolts aren't so long that they will touch the wheel when installed.

Mendes,

Do you have any pictures of the setup? Also, what exactly is a "T-Nut"?

thanks

Sorry no pictures. A T-nut is a.k.a. a blind nut. If your pant is currently held on with screws all you need to do is enlarge the holes where the screws are, so that the larger size bolts will fit through. Then install the blind nuts inside the pant.


O.K. Here is my attempt at a diagram showing this installation.
Bear with me...

I use silicone rubber between the pants and the landing gear. It absorbs the shock when landing.

Richard,

That is one great attempt at a diagram! Very nice...

Ok, makes sense...question so I know I'm seeing it right though. There are actually 3 holes in the aluminum landing gear, correct? One for the main axle and 2 for the screws going into the blind nuts right? I have heavy aluminum gear (from tnt) and only have one hole for the main axle. I'm guessing I would need to drill 2 more holes on each side of the landing gear for this system, correct?

Marc

Thats right, also depending on the size of your plane you can go with bigger bolts if necessary. On a 40%+ plane I would go to 6-32

Do you glue the plywood to the pants or just leave it as is for support for the blind nuts? Have to check to see if I can drill a hole below the landing gear axle as I don't know how close the hole is to the bottom edge.

The current setup has a "wheel collar" type of fitting that goes over the axle and has 2 places on either side of it to screw into from the outside of the wheel pant. The screws are small and the pants are thin so they are already cracking and flopping around a bit.

marc

Glue the plate to the wheel pant, it will be much stronger that way. The diagram that I uploaded before didn't show the following:


The bolts should not be directly on top and under the axle, position them so that they are offset, that way you will have enough space for the holes. In the diagram below the big circle would be the axle and the two small ones are the bolts.

thank!

Been using wheel pant 'holders' by Sig for 10+ years now and rarely have they ever failed. Only two small screws through the pant into their holder and the wheel collar does the rest. They come in (I think) three sizes.

Simple, easy to use and 'They Work'!!!!

Jerry

You have a product name or number we could use to search online for it? I'd be interested in this myself.

Part number: SH-720
(2) Wheel Pant Mounts
Fits 3/16th dia. wire ldg. gear

Sorry, but that is the only one set I have left, and I think that is the largest size. I know it isn't the smallest because I'm using a 1/8" axle and broke mine on a rough landing.

Hope this helps,

Jerry

I think this is what i have but it is not enough support to keep the pants from cracking. The wheel collar slips over the axle and sits inside the pant. 2 screws from the outside of the pant go into the holder collar which is on the inside of the pant. I am on a grass field but have not had a rough landing and the stress from the limited support has allowed the pants to start cracking.

Found the sig item...different from what I was talking about and not sure how it's used....here is a pic.

Remember seeing in one of those 'How to' pages...to use the common nosegear steering arm - glassed against the inside of the wheel pant, with the collar centered on the axle hole - it has the advantage of a lot of torque movement.

Just a thought...

Jerry

That's an interesting one too. I can see how that might work pretty good. I'm going to have to try one of these ideas cuz next flying season those pants are going to shatter on landing in the next few flights...wonder which one of these would work best?

Still trying to figure out how that Sig solution is implemented?

Sig 5/32 SIGSH727
1/8 SIGSH726

http://www.sigmfg.com/cgi-bin/dpsmar...Z+Sig+tecu3025

With the method that I described you won't have a problem, until you make a REALLY hard landing. Basically all that would be left after such a landing would be the plywood plate and the bolts, the wheel pant just gets ripped off. Don't ask how I know

Marc,
What size of wheel pants are these that you are having problems with? (tire size would help also).

Kelvin.

Kelvin...have to measure the pants..I think the wheels are 3" or 3 1/2". A guess at the pants front to back is about 5-6 inches? I can get exact numbers if it helps.

Also, can you add RCU to your link page whenever you get a chance please? Helps to get the word out

thanx

Marc

Link is up

Sullivan also makes a good set of wheel pant brackets that attach to the pant and axle; doing it this way if the pant hits something solid threr is a chance the pant will pivot rather than breaking. I'ver used these for years without any problems. I've even glassed the bracket into the inside of the pant.

This is how I attach mine. Simple and very effective. Use a 5/32 long steering arm. Attatch to pant on lt ply plate at the far end of steering arm witha small screw. Use lt. ply plates on both sides and drill thru to other side to hold pant level with axle. I have one season of hard surface and rough grass field landings and no stress cracks in the pants yet. Hope this rough drawing gives you the idea.....

I have the feeling by the time I'm done with this I can drill my plane into the ground at 120MPH and it's going to be shattered to pieces yet my landing gear, wheels and pants will be unscathed

Simple answer is to invest in a Sig 'Somethin' Extra' and copy that, or bail up one at your local strip and have a hard long look.

That system seems to be one of the better ones as far as I can see.

Alan W