How to remove paint from a carbonfibre monocoque?

[funformula]

What is the most effective but careful way to remove the paint from a carbonfibre monocoque?
Shotblasting with sand, glass, dry-ice, ...?
I heard that the Formula 1 teams remove the paint with sandingpaper before respraying the monocoques. The reason for that is the sensitivity of carbonfibre on waterabsorbation.
Does anyone has experience with this?

[JohnMiller]

DA.

[JimW]

Originally Posted by JohnMiller

DA.

It may not be the funniest post I have seen but is certainly the most obscure.

Regards

Jim

[Mackmot]

I think its a fairly obvious post and quite correct. Use a DA sander for quite some time. F1 teams have one advantage though, they use electrostatic painting so you end up with a lot less paint to take off.

[trikesrule]

Have experience with this. Acetone on a rag folded four times won't harm the epoxy and you will end up with a chemically free surface. And it doesn't put stress risers into the surface that sanding does. Will u be repainting or leaving a carbon finish? .........trikes

[JimW]

OK; the addition of "sander" gives Google enough to bite on. Why anyone might want to sand a Duck's ---- is still beyond me.

Regards

Jim

[funformula]

Originally Posted by trikesrule

Have experience with this. Acetone on a rag folded four times won't harm the epoxy and you will end up with a chemically free surface. And it doesn't put stress risers into the surface that sanding does. Will u be repainting or leaving a carbon finish? .........trikes

I don´t want to repaint the car. The carbon is looking fantastic.

My native language isn´t English, what means DA ?

[terence]

Its a make of Orbital Sander.

[terence]

Originally Posted by trikesrule

Have experience with this. Acetone on a rag folded four times won't harm the epoxy and you will end up with a chemically free surface. And it doesn't put stress risers into the surface that sanding do es. Will u be repainting or leaving a carbon finish? .........trikes

But it will take forever if the paint is a 2k,or for those who dont know Thermoplastic.

[trikesrule]

Terence could be right. Do u know what sort of paint is on it? ....trikes

[funformula]

The paint job was done properly by professionals, this was documented in an article in a tuning-magazine, so I guess its a 2K paint.
The car is the Reynard 913 which won the 1991 Monaco Formula 3 race with Jörg Müller. The car was repainted in 1993 in white/yellow Opel-Motorsport colours for being displayed in Japan.
If it´s impossible to remove all the paint, I would think about the original blue/yellow colour-scheme.

[sereneseven]

I've gone through this a few times and I agree to an extent that sanding is a good method...but I also have found that wallnut shell blasting works very well, the key though is to make sure your blaster is trained how to do it since if done incorrectly you can still damage the carbon you have to be very carefull and fight the urge to get greedy.

[StephenRae]

As the tub is 15 years old I would guess that the resin has cured as much as it ever will and will be completely inert, in which case a proprietary paint stripper based on dichloromethane will not do any harm if used sparingly.

[ss_collins]

out of interest what integrity tests do you do on a 15 year old tub?

Audi use a film instead of paint on the R10 - could make your life easier next time.

[funformula]

Originally Posted by ss_collins

out of interest what integrity tests do you do on a 15 year old tub?

What do you mean with integrity test? Can´t find a translation for that which is making sense for me.

Originally Posted by ss_collins

Audi use a film instead of paint on the R10 - could make your life easier next time.

The nose cover on my car was painted white and additionaly sealed with a white film. This happened back in 1993. Seems that they wanted to make their job 110% perfect.

[cnova]

When I was working in CART (1988-1998), we used several different media in a "blasting" process. They were crushed walnut shells, granular corn cob, soda & dry ice. Since meeting the minimum weight requirements were never a problem (we always had to add ballast) the paint shop would use a sandable PPG primer, wet sand it and then shoot the top coat. When they went to strip the top coat, by blasting, they wouldn't direct the nozzle perpendicular to the surface, rather at a ~20 - 40 degree angle to the surface and they would only remove most of the top coat, leaving the primer. They would then remove the rest by sanding.

[ss_collins]

by integrity I mean to check that the chassis has not aged, that there is no delamination or cracking anywhere in it, there are chassis makers who life tubs. One prominent firm said they do not like having people using their tubs for more than two years without a proper integrity check (which isn't that cheap).

Back on topic does stripping the paint damage the top layer at all? Also does the paint have any effect on the resin?

[Chris Wilson]

I removed years of colour changes on a 893 Reynard using water soluble Nitromors paint remover. there was no carbon or epoxy damage. It took ages as some areas had many coats and colour changes, but the end result was clean bare carbon. I reskinned the bonded and rivetted alloy floor of the tub, but if yours hasn't a full carbon floor be aware Nitromors will slowly corrode the alloy if not washed off properly. Hope this helps.