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How to accurately cut out plywood?

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Greetings all... looking for some top tips on how to accurately cut out various pieces in plywood. They are shown full size in the plans but too big to photocopy and not wanting to cut the plans up obviously. Is there a better system than tracing paper?
Always keen to learn and improve :)
Thanks
 

BJC

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If there are no dimensions on the drawing that you can reproduce on the plywood, you could get some poster board, lay the plans over it, and prick the outline with a pin, then connect the pricks, cut out the board, and transfer to the plywood.

I probably would consider the drawings consumables, and attach them directly to the plywood, and cut the parts.

What airplane?


BJC
 

Dana

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Get some drafting Mylar and trace onto that. I'll be much more durable and stable than tracing paper. Hint: use a mechanical pencil with polymer lead, then it won't smudge.
 

TFF

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1 to 1 lofting. center lines and measure. That or buy a second set and cut out.
 

Jay Kempf

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Get some drafting Mylar and trace onto that. I'll be much more durable and stable than tracing paper. Hint: use a mechanical pencil with polymer lead, then it won't smudge.
Oh Gawd that gave me a creeping flashback! :)
 

Jay Kempf

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I'm just old enough to remember ink on linen with those little ruling pens where you adjusted the gap and put a tiny drop of ink in between.

You guys are killing me. It took me so long to get off the drawing board and into the computer. Don't wanna go back. Although I liked the skill and quality of the presentation you could do with ink. Bloody capillary pens couldn't do a day without clogging. ACK!
 

Jerry Lytle

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Use a sewing type tracing wheel. That is what I used to transfer my full size paper loftings onto the rib material for a sail boat. The full size loftings were on standard printer paper. Use tacks or staples to hold the paper in place on the plywood during the process.
The prik marks were easy to see when it came time to do the cutting. Try to transfer oll the matching parts in sitting and under the same humidity conditions. Once tranferred the plywood will remain stable until time to do the cutting. The paper not so much.
 

Dana

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I'm just old enough to remember ink on linen with those little ruling pens where you adjusted the gap and put a tiny drop of ink in between.

You guys are killing me. It took me so long to get off the drawing board and into the computer. Don't wanna go back. Although I liked the skill and quality of the presentation you could do with ink. Bloody capillary pens couldn't do a day without clogging. ACK!
And even after CAD became mainstream, the pen plotters had the same **** Rapidograph pen tips... it would spend an hour plotting a complex drawing and clog just before it finished...
 

Topaz

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If there are no dimensions on the drawing that you can reproduce on the plywood, you could get some poster board, lay the plans over it, and prick the outline with a pin, then connect the pricks, cut out the board, and transfer to the plywood.
Or temporarily affix the plans to the plywood, prick the drawing (Wartenberg Wheel), sprinkle fine colored chalk powder over the holes. Pull away the plans and you'll have tiny dots of colored chalk directly on the plywood. You can use that either to connect with a pencil or pen (recommended) , or cut directly using the dots (don't sneeze!). The process is called "pouncing" and is a staple in the fine-art and woodworking worlds for transferring drawings from paper to the finish medium.
 

Geraldc

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I got a broken led tv and took the outer display panel off.
This makes a great light box to put your original on and put your paper on to and trace.A tv hire place gave me the tv to get rid of it.
 

Pops

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My wife and her sisters are all avid quilters. She has a quilting room with all kinds of nice tools, ( not allowed to touch without permission :) ). In building and covering the SSSC she even let me use her tools to make all of the pinking tapes. Has light tables and layout tables and rotary pinking shears, etc, etc.
 

miketun

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If you do decide to stick the paper pattern to the plywood, you might want to use a 3M peel-able adhesive. The pattern wont move while you work with it and you can peel it off afterwards. Use a very light tack-coat.
Using a water-based glue for this purpose is not a good idea. The paper will stretch, bubble and crease.
 
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lol... thanks all for the insight and comments all - much appreciated :)
Sadly the largest photocopying available here is A3 size... I called everyone in town previously!
I like the graphite paper idea and might give that a try in the first instance...otherwise the prick and wheel will be plan B...
Thanks again :)
 

robertl

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Greetings all... looking for some top tips on how to accurately cut out various pieces in plywood. They are shown full size in the plans but too big to photocopy and not wanting to cut the plans up obviously. Is there a better system than tracing paper?
Always keen to learn and improve :)
Thanks
A drafting business should be able to make copies.
 

geraldmorrissey

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Aug 11, 2008
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Lay it out. Get a pencil, a straight edge, a circle guide, a 12" scale (or longer), a compass, sit down and lay it out. I don't care how big the part is. By the way, try ink on mylar left handed.
Gerry
Bearhawk Patrol #30
 

cdlwingnut

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go to copy works and have them print you a copy you can cut up.
 
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