Building chassis for hotrods and
customs means I end up fabricating a lot of brackets. I want the brackets
to look nice, serve their intended purpose and be straightforward to
fabricate. I used to spray dykem, layout the holes, and plot a nice shape
using a handful of French curves. It works, but is a little time
consuming, difficult to get good symmetry and is tough to change the design as
you go.
I’ve started laying out brackets
using a simple drawing package. A low end cad tool would work, I’m
actually using Microsoft Visio because I happened to have it on my PC
already. Anything that lets you draw actuate lines and adjust curves will
work.
I can lay out the brackets, tweak
the design and print the drawing. Next I clean the metal, and use some
spray adhesive to glue the drawing to the metal. Next I center punch the
holes, bandsaw the part out, clean it up on the belt sander and drill the
holes. It works super.
A variation that I’ve used is to
layout the part in the same way, but instead I glue the drawing to some
sheetmetal and cut it out carefully with some snips. I use a Whitney hand
punch to make small holes where the part needs to be drilled. Now I have a
master, I can spray dykem on the metal, scribe a batch of parts, center punch
through the holes in my master and cut them all out. I can also use the
master to check the shape as I sand the edges smooth to make sure I get all of
the parts identical.
Attached is an image of a bracket
that I just made, it is part of a transmission mount for a TH-400, the finished
bracket has another component welded to it. I made two copies of the part,
and annotated one with dimensions and comments – I don’t normally do that
because I know how the part will be used.
This has been a big time saver for
me!
Joe McGlynn
