hi guys im new to the site but have often visited to serch for answers. i recently switched from west systems 105 resin to RR since it seems to be standard. my problem is when i get to the hot coat and gloss coat it doesnt level it self out. iv checked my mix many many many times and this is the second board im having this problem with. iv heated it, cooled it and used heat lamps but the same thing happens to me, when i first apply the resin it looks nice and level like glass. no ripples or pimples, but in about 2 minutes i notice it starting to pull together leaving tons of craters and starts to leave dry patches almost like there is a repelent on the previous coat, ?! the rails also look TERRIBLE like i took my bucket and ran drips down the whole thing. im so frustrated i dont think ill ever try RR again, i have to literaly brush and brush untill it gells and then sand out the brush marks to come out with a level finish. >:( you can say i use alot of sand paper… i work in a room moisture free and wind free so now i can only immagin that i was sold a bad batch??? does any one else have this problem
ps iv also used it on acrylic paint and tempra paint same problem
Hi - It sounds like possible surface contamination. Did you maybe handle the glassed blank with bare hands before fill coating? Finger prints are a likely source of surface cratering. Compressor oil from spray lines is another.
Maybe a waxy residue on your chip brushes. Did you change brands of brushes? I had this issue too and It stopped when I started doing a light wipe down with denatured alcohol and I also use a clean rag in alcohol to “pull out” my brushes before I use them.
I still haven’t found a chip brush that holds all it’s bristles straight from the wrapper, but I can’t see spending $10 on a brush I’m going to throw away in 15 minutes. I tried using a good brush and cleaning it after but it was still too stiff to use again after a few hours.
you know what i do have a 10 gallon aircompressor pretty close to the boards! so wipe down brushes and board with alcohol, would acetone work i have lots of it.
Are you using the additive F surfacting agent? That helps quite a bit. You can also try thinning the resin out a bit to help it level. I havent done it in a while but I believe I had used denatured alcohol to do this, it evaporates out before the epoxy kicks. Good luck
yes actually the first time i used additive F is when it happend but i soon realized it wasnt the culprit.i use heat to thin the epoxy and yes it does help and saves resin. i dont microwave it, i use a hot plate of alluminum i have lots of welding equipment so makeing things hot is not a problem i feel like it might be the oil in the air compressor. i used my paint gun to do this board and maybe some oil got onto the board, i am starting on a 511 quad next week and will post results
Maybe GL could chime in on this, but I’ve had bad experiences with acetone and “Not fully cured epoxy”. I’m pretty sure it will dissolve epoxy even if it seems cured. I was using it to wipe down some tools, (I was out of alcohol) and it softened epoxy that had already set for 24 hours. So if you’re doing your fill coat as soon as your laps are sandable, I think acetone would be bad.
ah yes it does say epoxy thinner on the can its just so depressing to do your gloss coat and have it turn out horrible. do you think it was oil in the aircompressor that got into my paint? i painted ontop of the hot coat instead of the blank this time. thats the only diffrence i can think of other than the resin
oil would be horrible for an epoxy that you’re trying to wet out with additive F. Degreaser, light sand, even a denatured alcohol wipe or a tacky cloth wipe before you gloss/fill coat. I know a guy that had issues due to silicone contamination from the crap he had right next to his glassing stand (in a garage) and most likely on the cloths and rags he used to “clean” stuff with.
silicone wrist bracelets are not allowed in clean rooms due to their contamination ability.
so it turns out that my aircompressor is oil less… hmm but i sure wont touch the board with my bare hands and i will wipe down with denatured alcohol prior coating wish me luck!
"i painted ontop of the hot coat instead of the blank this time. thats the only diffrence i can think of other than the resin"
Possibility of a paint incompatability? I would take some of the paint and spread it on a piece of window glass or an old board. After it dries. spread your epoxy on it and see if it does the same thing?
I've definitely had some weird stuff happen over the wrong kind of paint.
My guess is the paint. I Have done paint on Hotcoat then RR over and even with the same brand of paint some colours caused seperation (red and blue) as you described while other colours were fine (yellow).
So as John suggested test the paint, test different colours and really let it dry. any moisture in the paint and your stuffed. Let it dry fully. For Acrylic paints I wipe the dry paint down with light detergent and water and then rinse off with water. Let it dry again before you gloss with RR. Gloves on from that point on.
I am getting ready to try some hotcoat painting and wonder if you would care to state what paints/brands to avoid? Which to recommend? So far I have not had any resin issues (knock on my wooden-head) and want to keep it that way…
OK I have had this happen to me also. I will tell you this acrylic and epoxy don’t mix well at all unless you airbrush on the foam. I have tried 2 different kinds of acrylics (Nova and Golden) to airbrush on the hotcoat and 2 different epoxies (Aeromarine and Composite or whatever it is they sell at Mitch’s in La Jolla) to gloss with and I have gotten the worst separation ever. I need to break out the experimental board and post this, because you can scuff the acrylic or not and it doesn’t matter at all. Also 2-pac polyurethane that you spray will not adhere to acrylic either.
So if you want to airbrush or use acrylics on the hotcoat then you are going to have to do a polyester gloss. That was my solution and it seems to work. For whatever reason polyester will stick no problem to the acrylic. But if you have areas where there is no acrylic the polyester will have a tougher time adhering to the epoxy. I usually sand the board with 80 grit then do my airbrush work then give it a poly gloss and I haven’t had a problem yet doing it this way. The only thing is you have to do a good tape job if you airbrush since the board is roughed up with 80 grit. I hope this info helps…
Have tried a bunch of different brands of "craft" style paints from my local arts and craft supply shop. They seem to go OK but clog the airbrish if you do fine stuff and didnt stick to the epoxy fill all that well.
The best results I have had are with testpots (You know the ones you get at the hardware store for trying different colours on your wall) From brands like Dulux, Resene, British paints Taldmans... and the like. Thinned down with a little futures floor finish. They stick well and have fine pigments so dont clog the airbrush. Resene has been the best!
Hope that helps, there are plenty of people on here better qualified to comment on this one...speedneedle?
When you're beating your head against a wall trying to solve a problem, sometimes fresh thinking from another direction is useful....
From what I've read, epoxy is very sensitive to even the slightest surface contamination. You do lots of stuff that can create airborne particulate or mist, you got no chance to get good results.
So don't use epoxy! At least not for the finish coat. Fine to lam and hot coat, but as several have mentioned, poly resin is pretty easy to bring to a real nice shine. Yes you can get it with epoxy if you wet sand and buff forever, but poly resin, particulary UV cure, will provide the result much more quickly and with less expense.
i used Basic tm* liquitex arcrylic paint, i also used tempra poster paint. i use a automotive kawasaki touch up paint gun its GREAT! cost about 20 bux from pep boys and actuall sprays better (flatter and more even) than my bouble action airbrush. i guess the polly finish is the way to go my brother has a whole lot from a boat project so at least i get to save my expensive RR.
another thoght has anyone mixed the resin and shot it in a paint gun like they do clear coats on cars. its basically the same process, primer, paint, and the clear coat i think is actually a polly resin… might save some sanding
Paint is generally filled with silicones, surfactants and wetting agents. Resin doesn't like any of these. paint on the blank and laminate that and finish with clear resin. Putting resin over paint just doesn't work very well. If you want to paint the hot coat then gloss, gloss with a two pack urethane. Their made for this stuff.