Installing wheel pants
Danny,
It's been a year since I installed the new wheel pants on my older -6 but I remember the plans seemed confusing until I figured out what Van was trying convay. You have the plane leveled like it was inflight so you have to line up the pants so they are too. The hard part was finding points on the pants like lines or centers on a rounded object. I came up with a couple tricks to help.
Remember, all your trying to do is have the pant fly straight with the plane and not be a trim device.
First, to find the centerlines on the pant halves, I put them big side down on a large piece of paper, like the back of the plans. Then draw/mark the edge of the pant on the paper, remembering to mark the tire opening points so you can put the pant back on the paper in the same place. Once you have it marked, hold the paper up and fold the oval marking in half onto itself. The crease will tell you the center point of the top and bottom. So once the paper is creased, put the pant halve back on it and mark both points. At some point, you have to mark the front nose point. I set the front half on its nose on a table and looked for the point. Then look at it straight on and mark a point. Then go to the back pant trailing edge and mark the halfway vertical point. With the above information, you should be able to mark lines vertically and horizontally and have a front point and a rear point! you don't really use the lines for much other than helping you align the pant with the tire assembly. I used a piece of sheet metal to bend over the curves to mark the lines with.
With the fuselage leveled and gear off the floor in "flight mode". find the center of the firewall, plumb down to the floor and make a mark. Now go to the rear of the fuselage, find the center and plumb down again and make another mark. Now chalk a line between the two marks on the floor. Now mark parallel lines over closer to each tire. This closer mark makes it easier to measure from the pants to the parallel line.
Also I used a piece of heater hose 1 inch OD and taped it onto the top centerline of the tire and this let the pant rest on it and get the correct spacing above the tire.
Now comes the tricky part, imagine a skewer passing thru the front point and the rear point. That skewer is what is suposed to be level to the floor and parallel to the chalked line on the floor.
The idea is to just mount the pants with the lines lined up with the tires.
So I marked the centerline on the tape that is holding the heater hose to the tire and you can look thru the fiberglass and align the lines.
With these lines on the floor and the lines on the pants, you are ready to start rough cutting the axle and tire trimmings to get the two halves to fit together around the wheel/tire assemble.
Trust me, it takes longer to type this than do it!
I cut only what was rubbing at first and once I was sure of the alignment, I enlarged the cutouts as needed. I checked other guys pants and read how other guys worked on making a tight tire to pant fit and I settled on 1/2 inch clearance and it has served me well. Once that is done you can install the nutplates to mount the 2 halves together.
Once you are ready to mount the pants to the brackets. You have to assmeble the 2 halves together, align it correctly front to back and left to right.
You feel a little like a juggling act but the pants should be a snug fit on the brackets and I used a small stick under the rear tip of the pant to help hold it in place while I got everything in place to drill the mounting holes.
Then you have to drill the holes in the fiberglass to hit the nutplates you already mounted in the attaching brackets. I bought small light sockets and lamp cords and spliced up a network of small bulbs to tape in place behind each nutplate so I could easily see the correct spot to drill the hole.
Don't forget to install a few extra layers of fiberglass cloth at each attachment point to reinforce the local attachment area.
I hope this helps and doesn't just confuse you more. I figured it out so you should be able to also.
Bob Martin
RV-6