Carbon Console Overlay

Dang, I completely understand if you're getting frustrated as I've been there before.

at my previous shop, we had a customer who had several business jets in their fleet. They wanted carbon panels in specific places, much like your trying to do. This was my responsibility to produce samples for the customer as well as accurate quotes for both my company and the customer. Long story short and one of my career lows was that I completely failed and ended up not locking down the contract.

I tried everything I could think of at the time. Different resins, sprayed the clear coat on my surface, let it cure then bulk up layers of carbon, hot bonding and even prepreg. at the end of the day all that stuff did was enter new problems and new products to learn. Im sure there are people who can do what your trying to do with any combination of the above and have success but at what cost.

what I've found is that I had everything i needed and it would be difficult, near impossible (but doable for sure) to pop out a perfect panel and the ONLY way in my experience was with Vacuum Infusion. flat glass plate with wax and or PVA, brush it, spray it, it doesn't matter because your gonna need to finish it with and automotive clear coat for UV protective anyway. layup your material and definitely degas your resin. let it cure, scuff it with 400 or higher and spray clear. this was the best way to pop out near perfect finishes.

the home garage way I've been doing panels is a little more work but offers consistent results. flat panel wax and PVA, wet out carbon by hand, use a squeegee to move the resin around, peel ply, breather and pull vacuum. the side facing the panel will always have air bubbles, voids and defects that can be overcome but at a cost so I don't mess with that side. the side with the peel ply is the money shot. it will have a very very consistent texture and no air pockets or bubbles or defects unless I set it up poorly. sand it with 120 grit. because of the bleeder and peel ply there wont be much resin on the surface and therefore you wont have the white resin dust filling up holes. you can sand carbon fiber quite a bit before you damage the weave, however, i just sand it until the sanding dust turns slightly chalky in color. from this point depending on how flat your part is you can either start clear coating or add a layer of brushed on or rolled on epoxy. sand in between the epoxy and add as many layers as needed until its as flat as desired.

I think i've posted my longboard I built before. I used a 12k almost 20 oz carbon the weave strands are almost 1/2 thick. this stuff is crazy thick and difficult to work with. for my layup I did the garage method. just straight up wet layup vacuum bagging. sanded it put 10 or more layers of automotive clear on it. the clear was used almost like a high build filler. I did a final sand at the end and buffed it out. I was concerned about the clear being too thick but its been 8 years of riding it and its still like new, it even flexes a little over 1/2 inch.

it seems like a lot of monkeying around and it is but it really doesn't take that much more time. you could layup a 2x2 sheet in 30 mins, let it cure sand it for 10-20 mins, wipe it down, spray 1 layer of clear takes 1 minute, wait 10 mins, spray another coat, rinse and repeat. sand it flat and buff. maybe 2-3 hours of actual hands on time and your done.



sorry for all the words, im pretty geeky about this kind of stuff.

-Mark

 

Well, I started another sample today.

I made a dust tent so the part is covered for the cure.

Quite an adventure. I used Gringuard mold release and it fisheyed quite a bit; even with acetone.

I brushed it a lot! And was ready to give up.

sprayed it more and it started to look good

Tented it.

 

Well, I heated the part all day and it released nicely from the mould. It looks really good.

There are some lines in it related to my process in some fashion. Either a ridge in the peelply which I did flatten, or an unevenly laid bleeder film? I think I did not care about the bleeder and will need to next time. Part of me wondered about using no bleeder, but the release will be a nightmare and the part might end up dry. Think I will make sure it is flat in the stack.

Other than that the part looks nice.

The Sunshield came in a little thin at 0.010" or 10 mils. I think I can double it?

 

Excellent progress.

I'd never used Grignard mold release.

It appears to be carnuba semi permanent polymer mix.

Sunshield doesn't like semi- permanent release agents, they tend to be far too slick (slick and/or slippery is how the release people talk about the surface tension. Surface tension can be difficult to explain to the average guy on the shop floor).

Paste waxes work well, and left long enough so the solvents evaporate off.

TR, Honey wax, Green wax, and other similar products.

 

A big help. I really had trouble getting partall#2 to polish out. Took it off with steel wool actually.

I had planned for the big go tomorrow. But maybe I will hold off until I get better wax.

It was really disturbing when I started to brush out the fisheyes; they multiplied! Eventually; they all got littler and that was how it finally got to no fisheyes.

Do you have a preferred way to lay down the resins on the mould? I mostlt want to make sure the mold is wetted well so the carbon lays down nice. The Sunshield in my 3rd try was still a bit sticky at 6 hours cure; enough that the carbon would have stuck. So I wetted with a 4" paint roller.

 

I can't really understand what you mean by the other waxes.

partall#2 would not polish out for me..might have applied to heavy?

TR high temp is a carnauba wax. Is it not semi-permanent?

The supplier and I are both cornfused.

 

Carnuba is a simple wax base, not semi permanent. Semi permanents are polymers and aren't sacrificial, they tend to stay in place much longer.

With waxes some of it is lost to the part, so after a few parts being built it needs to be reapplied.

Semi perms can have a very low surface tension, this can result in fisheyes.

Green wax needs to be applied to a small area and removed immediately. If left to haze over it can turn to concrete.

TR has a few versions, each has a somewhat different set of directions, so read the can. The 104 and 108 work well. Get 108 if they have it.

There are a huge number of mold release products out there, it's hard to test all of them.

The windshield treatments even work, Rain X is used sometimes.

 

I used honey wax today. **** ton of fisheyes again. I was a little short on Sunshield. I had like 18 oz for 3' square area.

It is under the cure tent. Can't get more Sunshield until Monday. I have a tiny bit I could maybe eye dropper into the fisheyes after they cure...feel like it is a bit thin...

Do I

A-try to spot repair
B-get more Sunshield and try to spray more on Monday?
C-remove it and start over?

I think thin and some fisheyes will result in epoxy on the surface that chalks and yellows...

The honey wax proabably gave me the best beading yet!

post script

it is a redo, see the pic; it got worse after I walked away; not fisheyes; fish craters

 

You can use a brush over those places during application, or later.

When you get a spot like that its usually from wax residue that wasn't removed.

Honey wax has a good bit of solvent in it. It takes a while for it to flash off. I always come back and thoroughly buff the surface just prior to spraying.

One of the better waxes I've used was the water-based Honey wax.

It is very easy to both apply and buff out, I saw fewer fisheyes with it too.

 

I pulled the Sunshield off. Gonna retry it Monday after I get more of it.

I noticed quite a bit of pull back from all the edges of the glass. In the morning; I'll go mic it and see how thick it was..

 

Here is what I used. Carnauba wax it says.

Honey Wax Mold Release Agent https://fiberglasssupplydepot.com/Honey-Wax-Mold-Release-Agent.html

 

I've used Honey wax for about for about 45 years, it works well for most things.

I did fisheye testing with sunshield on glass with about 10 mold releases.

Sunshield is a bit more prone to fisheyes, it's one of those compromises on formula.

If you want a clear UV resistant product, that is compatible with epoxy and polyester in both in-mold and post applied applications, there are some tradeoffs. If it didn't perform like it does, then there wouldn't be a market for it.

There's a learning curve to spraying it, starting with very light dust coats, then slowly building it to where a full wet coat can be applied.

Flooding the surface tends to allow it to move around and create those bare spots.

Back to the mold release products.

Most worked well enough, but only when the exact directions are followed for that product.

Semi permanent releases tended to have more problems with fisheyes, but even some of those worked OK when used as instructed.

Semi perms tend to suffer from being easy to over apply, the surface can get so slick tape won't stick to it. If tape doesn't stick, coatings don't have a chance.

Applying a coat of wax over a semi perm can fix the problem though.

 

I gauged it an it is only 12mil. I am hoping for 20...

So, 12 minutes is all I have per batch at 2% and say 7% acetone?

if you get the craters; will swamping them work? Or next day, fill the puddle?

 

What gun are you using, and what tip size.

 

I am using a cheapo gun. I have an expensive one, but I can't find it? Wondering if it grew legs.

Tip is 2.0.

They say to stay around 40, but it seemed better when I tirned it up to 50 psi.