Dupont Chromaclear 7600s and 7776s used to be my main clears. They were great; however, I recently switched to a high solids PPG Omni MC161 and I haven’t looked back. Not only is the Omni cheaper, but it is more clear and builds better thickness. The only drawback is the 12-16 hour time to polish; whereas the Dupont was only 2 hours.
As for safety, technically resiprators aren’t good enough. Isocyanates will pass though skin and worn (old) respirator cartridges.
400 will be fine. I have no experience with polyurethane enamel clears. The type of clear you are currently using is fine. Although, IMO, you should find a more inexpensive brand. The Dupont I used to use cost about $55 for 1.25 sprayable quarts (1qt clear, 1 pint activator). The PPG I use now costs about $45 for 1.5 sprayable quarts (1qt clear, 2 pints activator).
Paint work is an entirely different ballgame. You will have a lot to learn =).
grrr… i knew you’d say that last line =\
If you just sand a part and do not carefully degrease using panel wipe product intended for use before painting, then this is almost certainly the cause of your problems.
Parts need to be grease and dust free, and you must not touch them after you have degreased.
+1 on the PPG clear works great I use the 2021.
this place is close by, do u guys recommend anything here?
thanks!
i guess ill have to order it from a paint place =. one stupid guy on the phone said i could use brake cleaner. yeah right! it will kill everything. or , what do u guys think?
my god dont use brake cleaner!!!
its a brake cleaner and not a paint prep product.
Just use what I use…DENATURED ALCOHOL.
It will desolve the wax from pulling it out of the mold and not eat the resin (unless you bath in it of course)
I use the HOK clear as well and its a great clear…you just have to have it prepped right. Paint is only as good as what it sits on.
lol i know i was just testing you guys. and i was going to try the alc. first thing tonight
i have to be doing something freaking wrong. there are dimples on the part right after clear coating =(. i think its dust, but how the HELL am i going to get a dust free part!? HELP!
Dimples are not caused by dust. It’s either fisheyes or porosity in your part. Fisheyes are cause by surface contamination such as wax and grease. Porosity will cause what appears to be fisheyes but is cause by tiny pinholes in the surface of the part. Got some pics?
Are you using ANY silicone based sparys in your shop? (like WD-40)
Nope, i do but far away. also, i washed the part down with soap and water. the surf. is very smooth before spraying, not smooth but dimple free. i have tested it. i think i will run 1 -2 more coats to cover this up then sand down and buff. UGH!!!
Larger dimples are called fisheyes…they are from contaminants in your part…ie wax.
YOU CANNOT SAND YOUR PART WITHOUT GETTING THE WAX OFF IT FIRST!
The wax will get imbedded into the part by the sandpaper if you sand it off.
USE DENATURED ALCOHOL TO WIPE THEM DOWN.
doh! i didnt know that part! i thought it was only AFTER you sand. ok, so demold, dewax or take off ALL the crap, then soap and water, sand, clean again and soap and water again. then let dry. tack cloth, spray clear coat… gosh,
Using soap and water to degrease parts is really not a very good idea! Get hold of some proper pre-paint degreaser, and I think probably your problems are going to be over. Always apply this using new soft paper wipes, so you can be certain you are not using rags that have silicon on them.
Soap and water to remove basic contaminants such as sanding dust. Then a quality cleaner/surface prep.
if you have a gel coat why are you wanting to apply a clear coat? For some UV protection?
…just curious and trying to figure what way I should go…
it gives it an extra layer of protection and i dont want to buff or sand the gelcoat (afraid of hitting the weave )