I tried something out of desperation and it worked well. While at the Team Trials in Muncie one of the Robart tires on my model finally went so flat that the drag caused the plane to ground loop. So I went to the hobby shop adjacent to the AMA site in hopes of either buying a new set of Robart tires or getting the foam inserts that are available.

Alas the shop had neither but they did have some Dave Brown Lite Flite wheels. Those are basically foam tires. So I bought a couple pair of the Dave Brown wheels (enough to make some mistakes) and went back to the motel. The Dave Brown wheels have a smaller hub so I used the poor excuse for a knife that I carry in my flight box to carve out a bigger hole in the middle. I only cut myself twice. Then I stuffed the DB foam inside the Robart tire and reassembled the wheel. The plane worked perfectly the next day.

I was so happy with the results I decided to do a better job and put new foam-filled tires on my model. A hole saw proved the perfect tool.

Here are the parts I used-3 1/2" DB tires go inside the 4" Robart tire

Off to the drill press. I had to drill from both sides.

DB foam partially forced into the Robart

With the foam completely inserted the tire looks a little fat. But after screwing in the hub the width is OK. There is only a slight bit of slop where the OD of the DB tire is smaller than the ID of the Robart, but you have to try real hard to notice.

Tip Submitted By: Chuck Snyder, USA