Yeh I agree ^ 

How much time did you spend trying to get the reinforcement in position? You have a dramatic amount of bridging there, that isn't the fault of the mould. Of course mould shape will help/hinder you, but at the end of the day you always need to put the time and effort into really forcing the reinforcement into the corners when you pull a vacuum.

you just need to a lot more care when draping the fabric. i really needs to be in contact with the mould otherwise you will always get defects. use a fine mist of a spray tack that is made to be used on the moulded surface directly, then place the fabric in the mould while working it in all the crevasses from the center towards all the corners. Do this layer by layer and you will be golden with the mould you have!

So as planned, I removed all the sharp angles by sanding until 240  on the mould and tried another infusion


but it was exactly like the first time



So I'm now trying to do another mould using polypropylene sheet than I putted almost flush with the edge of the tray.



I'm actually adding the release agent and thinking about what I will use to mould it.
I'm thinking about green epoxy gel coat, one or 2 coats of 200g black stuff carbon and 3 layers of 366g surplus carbon.
What do you think guys?

Typically on Uni-Mould its a minimum of 4 hours before doing the coupling coat.

If the primary cause is bridging of the fabric, you won't get an improvement by vacuum bagging as the problem hasn't been solved.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

thanks for your answer
I will follow your advices when remade a mould for sure, using polypropylene sheets for doing flanges in the same axis than the part edges.

Actually I try to same my 2 moulds sanding the egdes and adding gelcoat in the holes using a putty wedge to have in smooth, not easy but I will see.
Do you know how long it take for the unimould tooling gelcoat to cure at ambiant temperature (25°)?
I find for post curing on the technical sheet but nothing about ambiant. (I have one done with unimould to repair too)

If the problem remains for infusion, I suppose this mould will still be fully ok for classic vacuum bagging .

Cheers

Definitely looks like a lot of bridging on that edge which has caused all the voiding issue you have.

As you suggested, its probably in part due to the rounded edge with the wax. 

You could round it a bit on those edges to reduce the bend radius which would help.

If you remade the mould, I would cut a recess into the baseboard so the tray edge can sit flush much closer to the baseboard so the area filled with wax is much smaller and much flatter. 

A simple fix that may work is using some snips, cut a relief cut into the corner of the carbon as you lay it so the fabric is not so taught on the edges.  Cut just shy of the finished parts edge line so nothing shows up on the finished part.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Hello there and thank you for your attention
English is not my main language so I apologise if my explanations are not as accurate as it should be.
I did my first mould and infusion since 10 years and it resulted as a disaster. I hope I can find help/solution and my experience could help other people.

I did the mould of a little tray with green tooling epoxy gelcoat and epoxy moulding paste on a glass. I used filling wax to fill the gap between the edges and the glass as you can see below:

So I did the mould, did my first infusion and had this as a result:


I forgot to take a picture but I had a looooot of bubbles  visibles behind the vacuum bag.
I did the infusion as this: [ -- Dry Reinforcement -- ] / Peel Ply / R100-MP22 Perforated Release Film / FM105 EasyFlow Infusion Mesh / Vacuum Bagging Film
I can see too there is a difference of thickness 



Perhaps I'm wrong but I think the problem comes from me doing too sharpen angles with the wax. I think it results with air traps.


What do you think guys? Am I right? Don't hesitate if you have any other clue to solve my problem, I wouldn't want to influence you

If yes, I was thinking about putting back in place the original tray (to protect the mould) and sand the gel coat where there was wax to flat this and to have this sharpen angles rounded.
I think it's possible to had the same gelcoat if I go too far or if I need to had a gap filled, can you please confirm?

Thank you mates, I have my other mould (unimould) done with the same way so I don't dare to do the infusion if it's for the same result