7t2vette

I am dyeing some interior pieces, and have attempted to use the sand free on the hard plastic pieces with little luck. You are supposed to spray the part with sand free, then while the sand free is still wet, you are supposed to spray the dye. The problem is that when I spray the dye, it ends up drying all blotchy looking. How wet is wet? Am I letting the sand free dry to much? Do I spray the dye immediately after the sand free? HELP!!!!! What am I doing wrong here?

lbell101

The first coat of dye (misnomer) applied should be shot while the sand free is still wet. You need to apply a medium wet coat of sand free first. That means it's wet but not so wet that the application of the first coat of dye will cause it to run. The sand free bonds very well with the plastic. Shooting the first coat of dye while still wet will make the dye interface with the sand free for good adhesion. Subsequent coats of dye will bond well even after drying as it's the same product and will 'melt' together for good adhesion.

Does a subsequent coat of the dye make the blotches go away? It's possible the first layer could be blotchy due to the drying of the sand free but later coats should be fine. Are you shooting in high humidity? SEM dyes are very sensative to humidity and will appear blotchy or hazy if shot in that environment.

7t2vette

Yes, subsequent coats covered the blotchy parts, but it was many coats later. The blotchy parts were actually circles where the dye did not stick to the part. I believe that those circles were spots where the sand free had dried already. That stuff dries fast! I also was spraying the sand free quite "wet" because it seemed to dry so fast. Would I be better off to spray a section of the part with sand free followed by the dye as opposed to spraying the whole part with the sand free and then the dye?

lbell101

Yes - that is probably your best bet. It does dry fast.
What seems to work best for me is:
Spray the initial dye coat while wet.
Spray a light coat of dye on the parts - kid of a mist.
Then give it a wet coat after the mist coat is dry.

You don't need to use the sand free on most of the parts. Just the ones that have bad adhesion properties like PVC and ABS and Vinyl covering. The vast majority of trim in a C3 just needs a really good cleaning that will remove armor all and other stuff. I usually just use laquer thinner. I've used the sand free on small black parts like the dash inserts on later models and vinyl seats. The door panels and plastic trim in my 71 took the dye well without the sand free. No problems in almost a year now.

The_Dude

How will the sand-free work on the seats in my '79? I bought some covered cushions on ebay that are in better shape than the ones I have, but need to be dyed. I think they're vinyl and leather.

7t2vette

Thanks for the advice lbell101. I thought I had to use the sand free on all the hard plastic and metal parts of the car, and SEM's vinyl prep on all the vinyl parts. The vinyl prep is supposed to clean and soften the surface film
of the vinyl. Is that not the correct way to do it?

lbell101

They make a specific vinyl prep and leather prep and they recommend using it. It doesn't seem to be as good as using the laquer thinner and sand free to me. BUT I don't want to tell you not to use it as they do recommend using it. Really, the key to a good dye job is mostly cleanliness. The harder the plastic being dyed, the better the long term results will be.
Vinyl on door panels doesn't seem to be much of a problem but actually dyeing the seats has endurance problems. I've tried all the prep stuff on seats and no matter what, it's hard to get any real durability out of them (especially with a color change). The seats I've dyed using just laquer thinner as prep actually chipped off after a couple months. I couldn't tell a difference when I used the vinyl prep and ended up with the same results. The only time I was able to get any durability out of a color changed seat was using laquer thinner and sand-free... go figure. Even then it still wears through after a few months of daily use and needs a little touch up. Same color seats last longer for some reason. Probably has to do with less film buildup.
I've been buying new seat covers recently as I can afford it now and the results are much better.

If you take a look at my interior on my website....
That interior is almost all dyed except for the seats themselves. Even the new doorpanels and other parts I bought were redyed as I didn't like the match. It used to be much darker. I only used the sand free on the door panels and console. Everything has held up very well for almost a year now.


[Modified by lbell101, 12:38 AM 4/23/2002]

7t2vette

I agree with cleanliness as being the key to a successful job. The parts can not be clean enough. I first washed them with dish soap, then wiped down with 3M's wax and silicone remover, and then wiped down with laquer thinner, followed by Sem's plastic prep for hard plastic, and SEM's vinyl prep for vinyl. I have only tried to do scrap pieces so far as a precaution because I have never done this before. Thanks for all your help so far, I will ket you know how it turns out!