AARGH...Sanding perfectly flat 90 º?

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shrugger
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AARGH...Sanding perfectly flat 90 º?

Post by shrugger »

Well, the leading wing edges of my CC X-wing need a little smoothing.
Little bit rough and a couple tiny bubbles here and there.
So I'm wet sanding as carefully as I can to keep the flat edge
but its still coming out slightly curved.
Probly no one would ever notice the very slight curve, but being the
anal retentive that I am its really pissin me off :evil:
I've tried sanding it on the counter but I guess theres too much flex in my hand.
any ideas?
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Post by Andrew Gorman »

Tape your sandpaper down to a sheet of glass with duble-stick tape. This will keep you on the straight and narrow.
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Kylwell
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Post by Kylwell »

I use a large, fine flat file, about 12 inches long by 1.25 inches wide. Then tape some 400 or 600 sandpaper to the workbench and take off anything the file left behind.

And work slowly, checking the progress regularly.
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TER-OR
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Post by TER-OR »

To do it correctly, you have to take all rotation out of the equation.

Build a jig, secure your piece in that. On a flat surface, use a square block with sandpaper attached to it. Then you can slide your piece along that surface perfeclty flat.

Unless you do that, "good enough" will have to be good enough.
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Mark Yungblut
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Post by Mark Yungblut »

What ter said....

Although here is something I have found to be a very valuable tool to have around. Just tape the work to it then run it along the sand paper taped down.

http://www.ares-server.com/Ares/Ares.as ... t&ID=60626

I use mine quite often.

Another possibility is to get the small one and double sticky the sand paper to the angle. then jig your wing to where it is level.
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TER-OR
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Post by TER-OR »

Those might be even better. Thanks, Mark.
Though I should get a block of nice granite or soemthing for a perfectly flat surface.

I have blocks of wood in my shop for use with my saws and drill press. It's easier than tilting the table most times.
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Post by Mark Yungblut »

A granet block can be expensive. I used (I broke it after 7 years of use) to use a marble cutting board that I got at Pier 1 Imports. It cost 20 or so and you could tape down the sandpaper and wetsand as well. It made ofr a nice smooth surface to slide the angle blocks along.
"Tell me and I forget. Teach me and I remember. Involve me and I learn."
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Post by Kekker »

For smaller bits, and awkward places (I think the edges of an X Wing s-foil count!), I use one of a couple of things, depending on scale involved. A piece of aluminum t-bar, a steel ruler, or a thick piece of brass strip - 1/16" or so. All are rigid enough to prevent any curving you get with a sanding stick or doing it by hand. Often, I'll superglue the wet 'n dry to it so there's no slippage, and I find I can get right up into an inside corner without messing up the other side. With metal bits like these, the superglue can be scraped off easily with a razorblade.

For any apps that don't require absolutely precise angles (like doing the edges of parts that must fit together perfectly), eyeballing the angle usually works out fine. If it's good to a magnified eyeball, the average eyeball won't notice anything off, either.

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shrugger
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Post by shrugger »

Thanks everyone. :o
With buiding the wings open it's ok if the angle is off just a slight bit
so long as the edge is flat. Now if I was going with closed, then it would have to be absolutely perfect
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Mr. Badwrench
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Post by Mr. Badwrench »

If the wings were to be posed closed, they wouldn't have to be perfect either. They'd just have to be sanded together.
I speak of the pompatous of plastic.
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Post by TrekFX »

For a light-duty marble or granite work surface, just hit the flooring department at Home Depot or Lowes!!!!!

Still looking for a good-sized unglazed quarry tile (terra cotta or equivalent) for use as a pizza stone, though!!!
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