Easier mould-making for a ultralight Low Aspect Ratio

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wsimpso1

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As wrtten, the method in posts18 & 19 seems in complete. How are you establishing the flange and its angle?

You may search on "flange transfer" to see how we do it, and it may work. We first put on a flange over the top of rib using the plate, then laminate the angle.

Will Oratec bond on at your wing loadings or will you have to rib stitch? Also, remember that fiberglass is about 20% as stiff as aluminium, so these flanges might be kind of flexible...

Billski
 

Richard Roller

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Feb 15, 2018
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Olathe, Ks.
SUUUUPER thanks for this info. I didn't know. Makes work on my project really easy.
Packing tape, cool! I learned something new! When I was still doing composite work on the heavies I would quite often use peel ply on metal shapes for small quantity repetitive parts making. Sometimes I used the blue high temp nylon tape we had for the same situations. Both worked well.
 

Butch_58

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Jul 23, 2022
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Mansfield Texas
There are several ways to do what your wanting but 99% include sanding. Sanding sucks till you learn how to do it. I have never liked making a mold and trying to get it the way you want it. I always make a plug and pull the mold off that. If you make a plug, than you know what your finished parts will look like. If you use bondo, use a piece of spring steel to spread it. It will adjust to your contour much better and you will have to sand less.
 

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speedracer

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Packing tape, cool! I learned something new! When I was still doing composite work on the heavies I would quite often use peel ply on metal shapes for small quantity repetitive parts making. Sometimes I used the blue high temp nylon tape we had for the same situations. Both worked well.
Silver duct tape works too, as does clear packing tape. EZ builders use duct tape all the time. It's in the plans. I looked at a Varieze project for someone once. It had the worst workmanship I've ever seen. In 3 different places I could see duct tape UNDER the layup.... man!
 

Rik-

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Sep 13, 2019
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San Rafael, California
This is a simple means to make a mold or a plug to make a mold off of.

Formica sheets. They are thin, flexible and not very expensive (I feel if I had said cheap, well some cheap SOB would want to argue that point)

The sheets are slick and thus make for a great surface to pull parts from as this follows the garbage in garbage out rule very well.

I had a customer who built a boat plug and he sheeted the plug with white sheets of ordinary Formica, counter top material. Waxed it and then coated it with gelcoat glassed up a nice mold.
 

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Bille Floyd

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Sep 26, 2019
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In the end , it is hard to do better than a foam shape, covered
with 1 layer of 3oz to stabilize the foam ; wax + PVA-release
to build a mold.

Small parts ; I use the PFP process ,(epoxy faced Hydrocal-30
or Ultracal-30, with hemp to stabilize it). I knew a guy and his
daughter, molded a rented Dino Ferrari , (in sections) ; they did
it in 1 weekend !

Bille
 

Cardmarc

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Jun 16, 2021
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Ok, how about how to do a modified cowl nose bowl? Who could scan the existing cowl, modify the scan, then use a dxf file to cut a foam reverse mold for me? Or lay up the new nose bowl for a test fit? I may want to made several after they
Or, how would I make a mold of the original bowl and then modify the mold?
 
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