Any tips for flattening hot coats? I use my x strokes and last passes (flattening with the brush). Is there anything else that may get the hot coat flatter?
-warm conditions with low humidity is the ideal, that way you can get the extra styrene to adequately boil off.
-brush strokes matter, plus progressively lighter touch with each phase, but it sounds like you have it figured.
-work very fast, and set up for a 15 minute kick time to give time to flow out.
-spread out quickly, lengthwise strokes, cross-strokes, lengthwise strokes, lengthwise again (light).
-use a GOOD brush. 4" wide is best. very clean, bristle. “Purdy” makes a good re-useable pro-grade brush.
-sometimes thicker hotcoats will level out better if the added weight/bulk is not an issue.
What Plus One said.
I’d only add to make sure your stands are level, prep the board to remove finger prints, dust etc.
Once the resin is on and spread out check for pinholes and fish eyes and sort these out quickly before starting to level.
keep wetting the tape line to assist flow. Let the resin flow and level a bit between brushing in a different direction.
Make sure you strokes are long and even, across the whole length or witdh of the board, start beyond the tape line and dont stop or change speed till your off the tape at the other end.
Once done, walk away and don’t be tempted to fuss with it. dont touch it till its set.
Slop it on, spread it out, walk away…don’t fuss with it. Gravity is the best leveling tool you got. This might be fairly obvious, but make sure you pour the resin on to the board in even tip to tail line. Use multiple, full length pours. No reason to over the work the resin and pull it all over the board with a paint brush. Then all you got to do is conect the dry spots and level it out, just like you have been doing.
There is a fine line between too much hotcoat which will cause slabbing and orange peal, and too little which will leave tacky spots. Make sure you use enough cat to kick it off properly. The whole process shouldn’t take more than 3-5 mins to spread, and a total 15-20 to gel time. If the resin sits for 30-40 mins before kicking, then the bugs, dog hair, slabbing etc. appear. When hot coating & glossing gel time is you enemy. Get a little egg timer, and set the bell at 3-5 mins, that way you’ll know when its about time to stop.
One trick I use is right after I lay down the hot coat, level it out and tip it out…it’s still really green and wet. I tap the bottom of the board or jiggle it for 5-10 seconds of so to give the leveling / gravity process a jump start. But thats it, best is to walk away and let it do it’s thing. Do the jiggle too late in the process and you got some funky rails going on.
Temp, wind, humidity, UV vs Cat…all play a huge part in good hotcoat. You just can’t tell when it’s going to go bad on ya sometimes…That’s what they make 60 grit for.
NO AIR MOVEMENT !!!
LEVEL RACKS FROM SIDE TO SIDE !!!
Pour it out and brush it out quick…wiki-wiki,ya !!!
A clean brush is a clean coat !
Don’t keep f@#king with it…let it set and gravity will do the rest.
…the hot coat is not a problem, you can sand heavy like Resinhead said (but if you need to sand with 60grit, well, you f—ed the Hot coat)
the problem is with the gloss coat, cause there, no possibilities to sand heavy…so sometimes the brush strokes are really a problem
Quote:
...the hot coat is not a problem, you can sand heavy like Resinhead said (but if you need to sand with 60grit, well, you f---ed the Hot coat)
I’ve improved at hotcoats I think, but since I’m still green as they come, I use 60g on the hotcoat but only to quickly take down the glassed over fin box lips and the overly raised edges of the rail tape dam along the tail
Thanks to all the replies so far. One thing I did forget to do was check the racks with a level. (Did it by eye). But no majors with hot coating, I’m just trying to make sanding as quick/easy as possible.