Talk Composites - The Forum for Advanced Composites

Help with Mould Design!

http://www.talkcomposites.com/Topic14753.aspx

By baja_patient - 1/23/2015 3:33:28 PM

Hello Guys!

Have been off the scene for a while, but I feel a project coming up very shortly. Have been flying a lot of model aircraft lately and have a beauty of a waterplane. The thing is it came with some very very light glass fiber floats, I assume about two layers max. of some light cloth. Some harder landings cause them to crack in sum places and flex causing paint to chip off. I would like to produce them in Carbon Fiber, (2 layers light cloth 90 or 130 g per sqm) in infusion, possibly with inmould coating/gel coat.

My initial questions to everybody out there now are, what would be the best way to go about making these moulds, ideally I would make a two part (seperate, not split) vertically down the center line, so the parts could be subsequently joined.

The pictures show the potential plug I will be using.

http://www.talkcomposites.com/Uploads/Images/f1075238-00a6-4730-b906-d43b.JPGhttp://www.talkcomposites.com/Uploads/Images/5205788a-2dd5-4f10-86b8-1cab.JPG
http://www.talkcomposites.com/Uploads/Images/28b1fbfc-a82f-4e1b-b168-9755.JPG
 
http://www.talkcomposites.com/Uploads/Images/70ec63b1-f6e3-4f73-b9f3-3e60.JPG

http://www.talkcomposites.com/Uploads/Images/f5de71e3-459b-4426-89f0-53a9.JPGhttp://www.talkcomposites.com/Uploads/Images/d079d349-d39f-4704-8e81-6c62.JPG

I would make two moulds (halves) for one float, because they are symetric, apart from the tabs, which can be subsequently installed in a mirrored fashion.

I would be willing to cut a float lengthways if needed. Was planning to try the unimould system.

All ideas are welcome! Lets hear them!

Cheers
By Hanaldo - 2/9/2015 11:34:42 AM

True, but in my experience the tooling gelcoat itself will give a degree of stiffness. Certainly strong enough to apply the first layer of reinforcement to, and then after that you can lean on it a bit harder. You really shouldn't have to push on the roller that hard for one layer of glass, if you do then it's better to work the air bubbles out a bit with the brush first, then roll it. 

In any case, I'm sure these things would be more than strong enough to take a mould from. If the plugs aren't sacrificial and you want to keep them in good order, then the important thing will be to design the mould so that it releases very easily. But given the shape, this shouldn't be an issue.