Adam
Here are the directions Dana posted on the BOG reguarding SEM dyes and how to get good results. I hope this helps.
Ok, so ya want to change the color of some parts you have, or change the interior color all together or just make it look better. SEM as many of you know makes plastic dyes and vinyl dyes. Here are some basic guide lines for you to follow so that you can obtain good results and save some money paying someone else to do it. You should know this work is pretty easy to do if you can wield a rattle can somewhat well. The dyes are very forgiving, more so than paints. So this winter, take on this project, you CAN DO IT.
First you need to know that vinyl and plastics are slightly different. SEM makes a prep spray for plastic, and another for vinyl. Now, with that being said, I've used plastic prep for vinyl and had good results, but to play it safe, get the right prep spray for the job.
You will need the following materials.
1. SEM plastic prep.* ( or vinyl prep if your doing vinyl parts)
2. SEM Dye* in the color you choose. ( some paint houses can custom mix your colors )
3. A bunch of CLEAN rags. and several white ones for the final cleaning.
4. A soft tooth brush.
5. A soft bristle brush. ( this is used for doing door panels, seats, or kick panels, textured surfaces etc. )
6. Tac cloth, you can get this at any auto paint place.
*** depending on how much your doing will determine how many cans you will need. One can should do a complete set of door panels front and rear. Just make sure you have enough. too much is a good thing on this job.
Remove the part from the car you wish to dye and clean it up.
I can't stress enough about how much to clean the part. Use the prep spray well. It dries fairly quick, so figure that into your work pattern.
You should spray the part with the prep spray and scrubbing with the CLEAN rag and don't miss any thing at all. Use the tooth brush for hard to get to spots, and if doing vinyl, use it for the welting edges and threads in the seats. Use the brush for larger areas. Change rags often so your not just smearing stuff around and wasting the prep spray. Don't miss ANY spots at all and if your not sure, do it again. Do the entire part several times and with a WHITE cloth, do it again. If you see ANYTHING on the white rag. Do it again until the white rag is clean after you wipe it off. This is VERY IMPORTANT.
Let the part dry totally, if doing seats with thread or welting, let stand till the thread is try and use a rag along the welts to ensure it's dry and DID I MENTION CLEAN!
Once you have your part TOTALLY clean. Use the tac cloth to remove any fuzzies from the rags.
Now, as normal, shake the crap out of the dye as stated in the instructions.
If your doing something like an "A" pillar piece, spray a light coat ( tac coat ) on the piece. The dye dries pretty quick, and when dry apply another coat. Continue this until it's color is solid and not missing anything.
If your doing a seat part with welting, start off your tac coat by shooting the left and right sides of the welting so that you know the dye is getting down in there where the welting is near the seat. Do the welting ribs a couple of times lightly and then after dry, it will be time to do the whole seat.
Normally when I do seats or door panels I'll start by spraying across the sewn or pressed lines in the part. Next pass is with them, next is diagonally, and then repeat the steps again. Ending with a pattern that matches the lines on the part. Light coats work well and a good coat on the final run at it. Do allow the dye to dry between coats as the dye needs to be able to de gas.
If possible, try to do this on a warm day, or a heated area. It helps your work time greatly, but can be done in a dry area. As I said, this stuff is pretty forgiving. You will notice that after it totally dries, the textured surface will show again even if you got a little heavy on the spray in most cases. The stuff is great!
Once done, let stand for awhile till totally dry and install your part again and admire your fine work.
I've done carpets, headliners, door panels, kick panels, dash pads, A pillars, consoles, the works! You should be able to re do your complete interior of your car in a day or two.
Now, I'll say it again, don't scrimp on using the cleaner or fresh rags!
There is no need for a primer or any adhesion agent when using SEM dyes. Figure it this way, an adhesion agent or primer are what your putting on the part to stick to first, so there is no way the DYE can DYE the part if your doing that. The Dye will do exactly what it is billed to do if these instructions are followed and you CLEAN THE PART WELL. You will enjoy it for years to come.
Should there come a time where somehow you damage it, you can clean the area and blend in the color of dye again and repair it. Unless you have white, then normally the part must then be done all over.
As for doing seat belts, I've had mixed results for some reason there. So do those if you choose. I did a set of seat belts from blue to black and in the sun, they still had a gun metal look to them. I even tried boiling them in Rit dye with very limited results.