Creating a matt-finish on carbon

This is my first trial having a go at matting down carbon parts with a sandblaster. Used crushed walnut as it is really not that abrasive.

Part is a Carbon Performance swingarm cover that I never fitted. It has an extremely high gloss finish in the gel coat. Tried masking off the surface with a Superduke logo to see whether it has the ability to survive the blasting and create a two-finish effect. Seems to work OK but you do have to be careful to not start working away at the edges otherwise the sharp cut-off is lost.

I'm still working with a total loss set up so really need to get, or make, a blast cabinet or it will be expensive and wasteful to do all my bits. Also I guess you can afford to take a lot more time when you're not losing the medium and do everything more gently checking as you go. I was a bit rushed this morning and conscious of how much medium was just blasting away into the yard!
Gloss finish

Masked with transfer

Matt finish

It's really hard to show on photographs the finish. It changes so much when you move it about and the light changes.

This has a lot of promise, I like it so far. Are you going to experiment further or just do all your parts based on this? You shpuld be able to re clear if you are not happy with the result.

I need to do some more trialling I think. Only used one grade of walnut shells so far and they are still leaving a microscopically pitted surface in the finish. Maybe I can get finer / softer grit which will give a more perfect finish. Or maybe I have to T-cut a finish back onto the surface afterwards.

I also need to play with the different ceramic gun nozzles I have and the different pressures that the gun will operate at. And to do all this I really need a blast cabinet because otherwise my yard will fill up with wallnut shells and I'll be ordering it by the tonne!

My main concern is finding a technique that will give an even finish across large surface areas. Like this Confederate mudguard...

Well.

Spent about 4 hours yesterday experimenting and found a way to get the finish I want that is uniform and matt. It looks just as I wanted but I didn't use the walnut and blast gun. This was done with good old fashioned wet and dry and finished with wire wool. The finish then is so matt it picks up every finger print but a light wipe over with WD40 to clean and adds a finger print proof finish.

It's time consuming. Doing half of this front mudguard, (for finish comparison), took about two hours.

I want to paint a design/numbers on the matted carbon surfaces but want a distressed look.

Here's a first test on a spare swing-arm carbon cover. Sprayed in gloss white over a Superduke decal used as a mask and then removed. This works well - better than the edge from the rubbish masking tape edge I got round the edge. Will use Sellotape for the real thing - much crisper line.


Distressing options a bit vague at the moment. It's either hand-worked with wet and dry, the sand blaster or throw it in a cement mixer drum with a load of nuts and bolts and hope for the best!
Here's a few pictures I like for inspiration..

First go quite positive, this is sort of the look I'm after..


I think that what I will try next is building up the paint layers using some different tones of white. A base layer then a layer of off white, then white then a grey and then white again. If I build up thick layers of paint they will show when distressed and make the effect look older and less virginal.
I'm going for a look that seems like it's been through the wars a bit, like military vehicles with identification numbers that were stencilled on and then seen a tour of duty.

I've always loved old planes, WWI and WW2. Flying tigers and Werner Voss, (one of Richthofen's flying circus.) Both did similar things to their personal planes.

Toying with the idea of doing this on the fairing panels. It suits the SD I think.

Bic, did you ever find a suitable finish for your carbon parts? I've been involved in a bit of carbon development in the past and for production we use a clear coat with flattening agents mixed to the required sheen, but in prototyping we commonly use this:

It lays down thin and leaves a very consistent finish.