GI-7B Chimney Jig
by W4ZT 9/9/2006
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The finished jig. I made it from a piece of 6061-T6 aluminum stock 4-3/4" in diameter by 3" long.
Showing the mounting clamped in the chuck.
Inside. The jig is back cut to allow for cut pieces and to make for the extraction.
The PTFE blank fits snug
It must be driven in with a rubber mallet.
The PTFE fits flush with the surface of the jig.
I make a first pass to round the hole and then measure it.
Next pass finishes the hole to size.
Extractor made from a hex head bolt clamped in the tool holder.
Ready to go inside.
The bolt head slips behind the edge of the chimney.
Using the carriage I extract the chimeny.
Pulling in one spot works fine. It all slides right out...
and drops onto the extractor bolt.