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Old 09-19-2010, 05:07 AM
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Kwak Kwak is offline
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Join Date: May 2007
Location: Off the deep end
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OK, maybe it's no big deal that my template was off and my second set of molds were about to go screwy too. I just pulled out the original plans and traced the proper outline on the template and sanded it down to the size it should have been. Then I went and laid the template on all my cut boards and traced in the correct outline, and filling in the difference so that I had more than just a tiny line to guide by. I still had plenty of sanding to so there was still nothing lost except the little bit of time it took me to sand my template down - which was about an hour, tops.



Once that was done I tried to think about how I was going to sand the master board down. Yamaha Junkie supplied me with a makeshift spindle but using a hand drill brings in a measure of uncertainty so I tried to come up with my own fixed upright spindle on the fly:



It didn't seem stable enough though so I just made sure to clamp the board in the vise and handle the drill freehand, eyeing the outlines on BOTH sides of the board - and yes, I made sure they were lined up. Every so often I'd stop and overlay the board against the plans to see if I was getting close without going over:



I spent a couple of hours sanding with heavy grit sandpaper on the spindle and 100 grit wrapped around a piece of scrap wood. If I felt like the 100 grit wasn't getting the flat spots out I'd break out the drill again and give it a couple of passes "feeling" for the curve. Once it hit 11 PM though I decided to call it a night with the actual work. Here's how close I got:







They're actually much more accurate than they look here but that's because I wasn't pushing down on the board and the plans in order to take the pictures. The paper likes to spring back and the plywood is light in weight.

The next step is to get the other 3 boards to match this master board. Normally this would call for a router and a pattern tracing bit but I don't think I can get access to those so I might have to give my homemade spindle a shot!

BTW, after that I move on to finally cleaning up the bending forms. Here's a taste of how they look now against my new and improved acrylic template:



Yeah, they're off and I DO need to sand them a bit - but I'm told that they don't have to be perfect. I've heard that they can be about 3mm smaller than the outline of the mold to account for the thickness of the bent sides and that the wood will still spring back against the mold after it's been freshly bent.
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