I figured out a way that I might be able to insulate the pipe from the wood in order to keep the wood from catching fire. I got some fiberglass pipe wrap from the BBHIS. It cost all of $3.94, so if it doesn't work out I am not out a bunch of money. While this insulation is not intended for use with such high temperatures, I think it will help. According to the interwebs, the melting temperature of fiberglass is about 700° to 1000° F, so I don't think it will melt at the temperatures I am using.
Here is what I bought.
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Pipe Wrap Insulation is the correct Search Term
Before I put down the fiberglass, I chiseled out some of the charred wood. I just wanted to get rid of it and to see if it chars again.
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Chiseling the Charred Wood Out
The fiberglass batt is 3" across, which is just about perfect for my jig. It fits between the screw holes.
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The Fiberglass is the Correct Width
Since this batt is only 1/2" thick, I doubled it over on the wood.
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That is Two Layers of Fiberglass.
The pipe fits nicely on the batt.
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It Looks Like Everything Fits
So I put it all back together and screwed it down.
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We Will See What Happens Next Time
With that chore done, I went back to planing my next practice piece thinner. I figured out that I can clamp the board at one end so that the board is under tension when I plane, not under compression.
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This is Working Out OK
There is just one clamp at the tail end of the board, but it seems to hold it down well enough.
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The Clamp Holds Down the Board
After using the plane, I got out the cabinet scraper again to finish it off.
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The Cabinet Scraper Works Great
After planing and scraping, I got out my electronic calipers to measure the thickness of the wood. Most of the web sites I have gone to specify the desired thickness of the wood in millimeters, and this caliper reads back millimeters directly.
I measured the thickness of the board in several places, trying for a 2 mm thickness.
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1.98 mm
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2.21 mm
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1.96 mm
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2.34 mm
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2.15 mm
That isn't a perfectly flat board, but I ran out of time and had to quit. That might be as good as I can get it for now. I don't want to make it too much thinner in the thin sections. So I will use it like it is. This board is around 1/16" thick, and the one that I bent last time is around 1/8" thick. So I have cut the thickness of the wood in half.
My next step will be to try to bend a side again. Given the charring that I saw on the other board, I might try to adjust the temperature of the iron down somewhat and see if it will bend anyway.