Throttle Bracket

I made this bracket to hold the throttle assembly on the front of a 928S engine after the mechanical fan assembly had been removed. The bracket is made from two pieces of 6061 aluminum - one piece roughly 4"x5"x1/2" and one piece roughly 2"x4"x1/2". After being machined I welded the two pieces together and added a gusset made from 1/8" aluminim.

This was my first attempt at machining the back plate. Unfortunately I turned the wrong handle on the mill and moved the Y axis instead of the Rotary table and managed to flatten half of the lower boss. :/

I didn't have any appropriate t-bolts for the rotary table so I welded some from some steel stock and some M10 bolts.

Here's the piece of aluminum after being cut on the bandsaw. I also drilled out the two upper holes before starting to machine. The piece is clamped to my rotary table.
I used a Sharpie magic marker to scribe the outline because I don't have a real scribe.

Here's the initial triangle cut out on the Mill. I didn't do the bottom corner on the mill because it was quicker to just sand it down.

The piece has been roughed out and the two heights are set. The clamping method here is a little awkward because I don't have three of the correct sized clamps and one of my t-bolts is too short.
Everything up to this point was done with a 1" 6-flute cutter. For the rest of the work I switch to a 3/8" 4-flut cutter.

Here's the backplate mostly finished, although I clean up the upper arches a bit better later on.

Here's the upper arches cleaned up and the pieces has been polished on my buffer.

The Jet belt sander is indispensible! I had no idea how much use I'd get out of it before I got it!
Unfortunately I didn't take any pictures of the front piece as I was making it. Here the two pieces are welded together and I'm about to machine on side of the weld down to clear the bolt.

This picture shows the inside weld seam before I added the gusset.

The gusset is welded on. I welded both sides of the gusset and then machined the top side down just for looks.
You never know when you'll need a big hammer.

Here's the completed bracket, polished and ready to go!

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Text, photography and layout by C.S. Mo

Comments and suggestions to: randoma@vui.com

	This was my first attempt at machining the back plate. Unfortunately I turned the wrong handle on the mill and moved the Y axis instead of the Rotary table and managed to flatten half of the lower boss. :/
	I didn't have any appropriate t-bolts for the rotary table so I welded some from some steel stock and some M10 bolts.
	Here's the piece of aluminum after being cut on the bandsaw. I also drilled out the two upper holes before starting to machine. The piece is clamped to my rotary table.		I used a Sharpie magic marker to scribe the outline because I don't have a real scribe.
	Here's the initial triangle cut out on the Mill. I didn't do the bottom corner on the mill because it was quicker to just sand it down.
	The piece has been roughed out and the two heights are set. The clamping method here is a little awkward because I don't have three of the correct sized clamps and one of my t-bolts is too short.		Everything up to this point was done with a 1" 6-flute cutter. For the rest of the work I switch to a 3/8" 4-flut cutter.
	Here's the backplate mostly finished, although I clean up the upper arches a bit better later on.
			Here's the upper arches cleaned up and the pieces has been polished on my buffer.
	The Jet belt sander is indispensible! I had no idea how much use I'd get out of it before I got it!		Unfortunately I didn't take any pictures of the front piece as I was making it. Here the two pieces are welded together and I'm about to machine on side of the weld down to clear the bolt.
			This picture shows the inside weld seam before I added the gusset.
	The gusset is welded on. I welded both sides of the gusset and then machined the top side down just for looks.		You never know when you'll need a big hammer.
	Here's the completed bracket, polished and ready to go!