Twenty years old and still in the rotation. This is from a local event that I ran or race walked several times. I imagine 20 years ago I was still running. I'm not sure when I started race walking. I started the blog in 2008, so no help from the archives. The shirts held up well, though. There's a couple of grease spots on the front but the collar's not all frayed. I think that's because it's green - not really a fan of green shirts.
Paper pattern to check fit and size before making the real one. I made a layout on the bench top first. First step was determine the circumference of both ends, then lay out the lines for the length and sides equidistant from the center line. I then double checked things by actually doing the layout for a truncated cone. That gave me the required arcs for the ends. I transferred the layout to a piece of pattern paper, rolled it up to check the sizes and then stuck it on the #1 cylinder tube to see how it was going to look on the car.
I transferred the paper pattern to the sheet metal, cut it out and then made a "joggle" along one edge. Rolling the cone was a little difficult. The 16 gauge is pretty stiff and the small end is smaller in diameter than the rolls on my roller. Plus, in spite of the fact it's a slip roller, I've never had much luck getting the sheet to slip properly so both ends roll evenly. The joggle on the one side is to allow me to lap the ends rather than trying to butt weld the seam. I ended up with a couple of dents while squeezing it together that I'll need to planish out but that shouldn't be a problem.
I'll get the seam welded up today and see for sure if I've got enough bends to finish the job. I think I might have to buy one more U-bend. If so, I'll order a couple of plates and gaskets to join the collector to the tailpipe while ordering.
No comments:
Post a Comment