Make a mat finished Carbon part

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#1

So… I still need to do some finishing here on the plug but i was wondering if you guys had any thoughts on how to use this as a mold. What i am trying to do is create a dash with a matt finish so that i don’t get glare when driving around. My though process was to:

  1. finish the seams off with Plasticine, apply mold release do the layup, add peel ply on the top (for a matt finish), infuse.

  2. Add bondo to the edges, coat the top and polish, do the layup, add peel ply, infuse.

the issue i see is getting the peel ply flat so that there isn’t any wrinkles and keeping it in place.

What do you guys think? Maybe a different process? I am trying to avoid a mold…i highly doubt the dash will come under any damage from regular use so having a mold doesn’t make much sense. I hate storing those things too for one offs.

#2

Hey mjalaly,

sorry if I should have got this from your post… are you pulling a part off the plug or from a mold? is this a part that you could lightly spray with a mat finish clear coat once the part is built?

#3

I concur with Central.

Maybe spray after with satin/flat two part paint. There are additives so you can create the sheen you want.

#4

Yes, I would like to pull a part directly from the plug without needing a mold. Like in the attached drawing. The problem I see is getting the peel ply to stay where it needs too without creating wrinkles. This would give the finish i want without having to make a mold.

#5

It’s important to remember that peel ply is a woven material and can be manipulated in the same fashion as carbon or glass. I usually start with my 0/90 and work out the corners. This is obviously not as easy as cutting and splicing but the result will look great! I (lightly) use supper 77 spray glue to keep the plies in place.

I am curious though, aren’t you worried about this part deteriorating in the sun without any UV protection?

This part had one piece of peel ply on the back and the fron was similar to secondary spray with mat additive.

#6

Those look like i want however I cannot get my peel ply to stick to anything even with the 3m 77. it is great what it is so easy to remove but bad that i cant get it to stick for the life of me.

Yes it will need a clear something for UV protection. So you used peel ply on both sides? were those infused?

#7

We use one of the economy lines from Airtech for our peel ply. I think it is Econostitch G but don’t quote me on that. Anyway its harder to pull out but much easier to lay in. Using a peel ply with less release coating insures that we don’t over do it with contaminants like spray glue which also helps to keep resin flow at its best.

The finished side of those parts is actually that way out of the mold. We lay in clear gel coat into a mat finish aluminum mold and then peel ply the back. No secondary UV protection is needed.

#8

I’ve noticed a trend on this forum, as well as some others, to apply a lot of tech to simple problems. This doesn’t appear to be a part that is highly structural or something that needs to be absolutely the lightest construction. Why not just do a simple wet layup? Infusion comes with it’s own set of issues. Infusions need an airtight mold to be successful. The mold also needs flanges and some beef to keep it’s shape. Not to mention the problems you’ve already identified with peel ply.

You could easily use the materials you have there (melamine?) to create the form you want. Lay up the laminate over the form and do a minimal amount of finish work and have what you want without all the hassle of a infusion quality mold.

#9

I agree with this statement, in general, but truth is there is always an “easier” way to solve a problem depending on the opinion of the person giving advice. Personally, I avoid hand layup at all costs and figure out ways to get what I want without smearing resin around. Besides part quality and consistency, I don’t like to go home smelling like chemicals. In this case, I would forget the flanges altogether and envelope bag the entire assembly. Once the dash was made, I would grind off the edges to separate the two.

Another option might be to build your dash out of a really good cardboard and wet layup a couple layers on the top and bottom. As long as you don’t go too heavy on the resin the cardboard will soak in the liquid and act as a hollow core. Using what you have, this could be a good alternative?

I am really curious to see how you proceed.

#10

I have redone this mold quite a few times. Right now i think i will make a plug, pull the mold and make a part.

#11

Does anyone know of a peel ply that will leave a smoother finish than most?? Less texture. I want to lay this dash up this weekend but i think my stuff will leave too rough of a surface… thoughts? I don’t think it can be sanded smoothed without adding a clear coat to build above the carbon layers.

Some how spyderco does this to their knife handles…

#12

http://www.elitecomposites.com.au/vacuum-supplies-equipment/vacuum-bagging-consumables/release-fabric-peel-ply-fine/

#13

know of a us supplier?

#14

If you want UV potection then you’ll have to add a top coat, so there is no point in using peel ply on the surface. I’d say go with a wet-lay skinning type of technique, as this is going to be faster overall. Once you have the resin built up and flatted properly, finish it with a matte lacquer.

…Anything else (i.e. making a mould) is just a waste of time - take it from someone who’s wasted a lot of time recently!!