RV9A main wheel pant to tire distance

RV9A,,,,Trimming main wheel pant for mounting what?s good clearance for sidewall of tire to wheel pant opening and clearance pant to tread area of tire?
Ron in Oregon

I went with half an inch all the way around, the same as many others, and it worked out fine.

Tom
RV-7

Hopefully this is not a thread highjack, but I think it is on the same subject. The instructions have you determine the top center of the wheel pant. How do you draw that line front to back when there are no obvious markings or llines on the top of the pant to help determine center. Do you measure from the scribe lines up and over the pant?

Looking back at my build log it's not entirely clear. Just says I aligned things the best I could by eye. You just want a few plumb bombs and tri-squares to help you get things close to center as possible. I think there are some posts by Dan Horton in the archives on this that are worth looking at.
This is the time you want to think hard about the bigger tires, if you are ever planning on operating off grass or gravel. I had to go back later and re-trim my wheels again. If you do go down the path of 380-150x5 tires, they are and inch wider and an inch larger in diameter, so you just use a 1/2" spacer block on the top instead of the 1" specified. They fit so well it's almost like the wheel pants were made for them. If you are only operating off sealed airfields, then stick with the smaller tires, as these larger ones are more expensive to replace, however this is not an issue on grass as the tires essentially never wear out. Mine came out great, and very glad I did it as 90% of my operations are off grass or gravel. There will be a 3lb weight penalty however (1.5lb each tire). You can re-use the same tubes.
Tom.

Thanks Tom I?ll go with that advice. Dave on setting up square I was told to start with the trailing vertical fin straight edge. Center of fin to be 8 5/8? off the pavement then I used a square to place against the fin. I found the pant wheel hole was just a hole and wasn?t centered or square. Set the pant on a table with the square at the table fin. Look at the bottom of the wheel pant hole and trim the longer side of the wheel pant on the table surface so the pant sets up level on the table surface with the square at the fin. Now I looked at the pant nose and to my best eye figured the center. Just on drawing C-2 this point will be the spot to measure the 8 5/8?. I used a laser level to shoot a line between the two front and back 8 5/8? points on the sides and over the top. Now measure the width of your tire add half inch cut that opening in the aft pant but only on the sides this allows the pant to be slid on to the mounting brackets with the one inch spacer on top of the tire. Use the bracket plans location and trim the trailing edge of the pant wheel hole to gain the fit of the tire. You are very close to the permanent location. Assuming you have fitted the two halves to perfection with platenuts and screws I slid the front half of the pant toward the aft and trimmed the wheel hole to fit. That?s where iam at now. Oh I jacked my plane up on to wood blocks to level the cabin longerons as stated in the plans. Then I stabilized the aircraft from moving,jacked up one wing and took the blocks out from under one of the main tires and releveled the plane to see how the landing gear axle and wheel changed in a airborne configuandration. As I am at this point I used the plans direction to figure centering the flying wheel pant location by projecting a chalk line on the ground under the center line on the tire thread. I have read the instructions over and over and your wheel pants may not be the same size or configuration. I hope I wasn?t confusing on my dissertation experience. My laser level shoots two laser lines at the same 90 degrees from each other. It gives me a good tilt angle when looking straight on to the wheel pant from the front of the plane. Course I have flown the plane for two years and now it?s wheel pant time. I hate it! Ut iam told I?ll love it when it?s complete. Ron