Sunday, February 12, 2012

Part 17 - Covering the seat

With the seat pan in hand, it's time to cover or upholster the seat. Since this was my first attempt at making a seat, I used lower cost vinyl bought from a fabric store. The seat padding consisted of an exercise mat bought from Walmart with a layer of soft 2 inch foam glued to the top of it. A sharp long blade knife was used to shape the padding. After the rough shape was complete, an angle grinder with a 50 grit abrasive disk was used to improve the profile and smooth the padding. If the padding is not smooth, you will see the ripples under the final vinyl covering. This smoothing operation didn't work too well with the soft white foam mind you.

Foam padding before smoothing

Trial fitting - testing for comfort

The vinyl was cut into a sheet about twice as large as the seat. Working roughly from the middle of the seat, the vinyl is riveted to the seat pan on one side, then pulled really tight and riveted on the opposite side. Then the next hole on the original side and then more pulling for the opposite side. After that it was pretty much free-form watching for ripples in the vinyl as I went. I punched holes in the vinyl with a sharpened piece of all-thread - I recommend a proper hole punch. The warmer the vinyl is, the easier it stretches. Careful use of a heat gun may be helpful to help stretch the vinyl to remove ripples before it is riveted in place. I folded the edges over double to decrease the chances of having the vinyl rip at the riveted holes.

3/16" aluminum rivets
Under side - vinyl riveted to seat pan

Completed seat

Final test fit

Another view

The seat is extends over the side rails which gives it good lateral stability. To secure the seat to the frame, a plate was welded between the two side rails and a 3/8" clearance hole drilled through the middle. A 3/8" bolt is inserted from the under side of this plate and threads into the t-nut epoxied into the seat pan during Part 16.
Seat attachment point

Now that I have some idea how to go about upholstering the seat, I intend re-doing it with leather at some point in the future.

1 comment:

  1. i have the same pipes on my el bruto 113, and they sound AWESOME with no baffles, although i do pucker a bit when i go by the cops, lol