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Old 01-10-2012, 12:22 PM
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raptureboy
 
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Default RE: How flat should a workbench be?


ORIGINAL: cutaway

Depending on the plane, 1/64th of an inch can discernible in flight. I have a friend with a Sun Racer that has about 1/64'' washout in one of the wing tips (probably because it was popped out of the mold too soon before the resin had really set). I noticed the plane wasn't tracking through loops without a tendency to start rolling out about half way through. Then I saw he'd cranked some aileron trim in to try and counteract the slight warp, which of course only worked perfectly at the precise speed it was trimmed at. A fast pass at buck thirty, and that trim didn't work anymore.

FWIW, if you're serious about building, the gold standard would be a machinists table or piece of granite countertop. I noticed Home Depot has some relatively inexpensive granite these days. A couple hundred bucks worth of countertop would make for a very nice building surface.
If you call $ 25 a sqft cheap[X(] How flat do you think the building tables in China are? A reletively flat surface will do it for most all of our planes, except maybe the most precise pattern planes. I rather doubt most planes are that straight after being stored in garages and basements for the winter. Check the doors you buy for warp at the home centers, the way they lean standing up can put a pretty good bow in them. If you use a saw horse make sure you use 3 so the middle is supported.