Making a mould is pretty simple, and anyone can make it, it's only time consuming.
Using the right cloth and laminating process makes all the difference.
I use Frewax as a releasing agent, apply a few layers of tooling gel coat, which gives the mould a solid surface, not allowing cracks etc. Let sit for 12 hours, tacky or not, as long as it isn't wet, start by applying 3 layers of 1/4oz chopmat. I do this as it's easy to work around the bends/creases/corners/edges.
Use a bubble roller after each layer is wet, roll the cloth, forcing all air pockets out (possibly why you had leaks too). This also helps by marrying the upper layer to the other end under.
Move onto laying a heavier gauge cloth, 3/4 oz chopmat. Usually you'd like a 3/8" mould wall thickness.
Moving onto making a part.
Cut the cloth to size.
I'd spray an in mould clear, I use duratec clear. Let it tack up, start laying your cloth, be nice to it, no kinks!
You've got the rest covered from peelply to bagging. Advise would be to put a full vacuum perimeter around the part with peelply strips acting as toes from the part to vacuum. Its also best to have some sort of flow media placed ontop of the peel ply. This helps move the resin equally onto the part. Also decreases thr chances of having dry fiber.
There are many ways you can place the feed line, feed run lines, and vacuum lines on a part. Each will give a different response.
Have good vacuum, 27 to 30 inHg, start the infusion. I'd mix one half kilo at a time. If you think you mixed enough, mix a little more until the resin/hardener is uniform with no resin toes (resin stringies).
I've been thinking of making a carbon hood, but the shop is very busy. Group buy is a possibility with enough interest. We can make one offs too. Top notch quality.
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