Middle of Epoxy Moulding. NEED FAST ADVICE

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#1

Hey guys.
I started making the mould yesterday. I had an emergency and absolutely had to leave. I did two layers of 3 oz fabric and one layer 10 oz fabric.
This is epoxy resin and surface coating.
I have wood framing to allow me to attach the gussets.

The resin has already cure although it has only been 20 hrs at this point.
Can i keep adding layers? I need to add at least 5 more layers fo 10oz and 2 more of 3oz. Then mount my wood and put my diagonol bracing.

What is the longest I can wait, if at all, after my inital setup has cured to add more layers.

I attached pictures for help


#2

yes, as long as you sand it first you will be fine. when I build epoxy molds I will laminate over 3 different days building the laminate up to thickness I want. I also vacuum bag all my epoxy molds.

#3

Okay, so i can leave the mould there as long as I want and start laminating again after i sand?

What grit sandpaper should I use?
I noticed that the epoxy wouldn’t stick to the wood framing i have in there. Should i rough sand that to help it stick?

Am I screwed since i didnt vacuum bag my mould? I thought about it, I didn’t it it was nescessary because of the large radius on the panel.

#4

You are not screwed since you did not bag your mould. I never have and havent had many issues. Sand with a rough grit to allow better bonding. You can also drill tiny holes in the wood to increase surface area.

#5

You might want to wash the cured surface with warm water and a red Scotch Bright pad, to remove any amine blush. After a good drying, scuff the surface with 80 grit for the following layers.

#6

yep 80 grit would be fine. i also add layers with days in between, i dont have much free time and these things are very time consuming.

#7

Excellent! news

Im going to give the layers a few days to dry before i touch anything. My scale was a bit off so I want to make sure everythign is fully hardened.

Let me ask you all something while I have your attention.
I was having a lot of trouble during the layup procedure for the second layter. Because these were cut so that I can lay my material at an angle.

What did you do to help your fabric from moving while you were saturating adjacent areas?

What are some layup technique when dealing with this epoxy resin?
The rubber squeege seemed best for me.

#8

So I sanded the mould using 150 grit then used 80 grit. This is what i had around.

Im not sure how much sanding I should have done, but It seems smoother now. Maybe a little more sanding wouldnt hurt.

I also cut my layers and have everything ready for the next time i laminate.I’ve got 3 layers down, gonna do 4 more. Possibly a few more of some lighter fabric.

Then, Going to add all my wood and bracing for support. This is all pretty new to me, so Im learning as I work.

#9

If you want to eliminate the sanding stage between cures,have a pre-cut piece of peel ply to cover up the wet epoxy (cut to the pattern size). After the initial cure, peel it off to leave a nice texture for the new layer(no washing and sanding).

#10

Coool little trick. Thank god this mould is done! I just need to add the wood and gussets, then touch up any damaged areas of surface coat.
I hope my parts work, keeping fingers crossed…