im trying to sand a gloss coat on an epoxy board and I can’t get anything sanded cause the paper is clogging immediately. I started with the sander and a 220 grit pad. Basically it wasn’t taking anything off and I looked at the paper. Completely clogged so bad so I can’t even take much off with a wire brush. I then tried 220 by hand and that clogged up just as fast
The gloss coat on the deck was put on 2 days ago. The bottom done last night. I’m in New Jersey and it is December so the shed is in the 40s-50s except when I put the heat on during the resin work. Could the epoxy just not be cured enough? I’ve brought the board inside and have it in a hot room but the epoxy feels hard.
What else can be done to keep the paper from clogging? Attached is a picture of the sand paper after I tried wire brushing.
First off, you know how the bottle says sandable in a few hours? Forget that, wait a day.
Next, you are pushing too hard, heating up. Lighter pressure, slower speed. Constantly blow the dust off before you pack it into the sand paper. Lastly, wet sand with a little dish detergent in the water bottle.
After that, surrender, because you can’t ever polish epoxy. You can get it close, but for gloss, you need to top coat with acrylics. UPOL spray works, after that 2 part auto spray finishes.
I know I’m not getting a great gloss to it but I’ve done a board like this before and it gave a good finish
How much pressure should you out on the sander? Do you press down at all or just let it rest on top of the board? The deck had been cured for over a day which is where I got clogging first.
also I tried going by hand and in a few swipes(about 10), my sanding paper was covered in epoxy. Almost no shine was even taken off and it was already clogged the first epoxy board I did in June/July didn’t have any clogging problems. Is my whole issue just epoxy curing in a cold shed? There isn’t much I can do about it other then wait till summer. I have heat that I keep on for a bit but I have to turn the burner off when I leave since its to dangerous unattended. I usually keep the heat on long enough to cut laps or pull tape.
Assuming that you properly mixed your epoxy…absolutely 100% the problem is the cold temperatures durring the curing process. Now the question becomes will it ever fully cure. Bring it indoors and crank your heat up to 75 for the day or create a heat box of some sort.
As for getting a gloss out of epoxy…absolutely it can be done if you wet sand to 1200 then compound and polish. You’d be surprised how much shine you can bring out.
That’s what I’ve heard. My first attempt I started out too low. With 120 grit and just never got the big scratches out as I went up. That’s why this time I wanted to start at 320 but I only had 220 and 400. So I went with 220.
Most epoxy come in a clear version , and can be polished to an acceptable level…they just don’t stay clear for long without a coating of something that has good UV filter…what this basically means , is that your epoxy is the filler coat , and only needs sanding , rather than polishing. Adding pigments to epoxy can make them soft , if you use poly pigments…and they melt too easy with sanding heat , and clog up the paper…the pigment powders seem to be the go , or epoxy specific pigments.
Are you saying that it won’t cure fully even with proper ratios since it was in the cold? It’s been in the 50s here but the shed was warned into the 70s and stays warm for a while after the heat is turned off.
If you want a really sandable epoxy resin, up to high polish, you need to increase barcol hardness. To do that, cured your board at 45/50°C for about 12 hours, with RR resin.
yeah, toaster oven, aluminum foil. put it in the attic, under a black tarp on a sunny day, in board bag on top of car hood over engine after driving, take it to the sauna at the gym with you, etc… lots of work for the gloss, but some people like it.
I’ve had some good luck polishing my epoxy boards with that stuff you use to restore car headlights. I tried it on a whim, and it fills in scratches and shines up nicely. That, and a random orbital sander seems to have a bit more bite and doesn’t heat up as quickly as the standard orbital. I use one that creates it’s own vacuum and the disks have holes, so it clears the dust for you and helps prevent clogging. However, to get a nice flat board, I hit it first with the orbital to make it all level, then switch to the random orbital and Abranet sanding disks. But if time isn’t a concern, bring them inside for a few days or cook them in a hot-box if possible.
It seems for me, as mentioned above, the main difficulty in sanding epoxy is it getting a little warm when sanding which is when it starts clogging up the paper.
I have had luck in wet sanding, from 180 up. It is harder in the sense you don’t have immediate feedback, i.e. you have to wipe the board with a towel to see any shinys. but my paper lasts alot longer, and doesn’t gum up.
A friend has a festool orbital sander, and that is magic. As mentioned above it doesn’t get clogged as easy, and seems to keep the surface cooler when sanding.
On my last board after taking it to 320, I used a marine varnish, e.g., epifanes high gloss marine varnish, and it worked really well. I thinned it 50% with their thinner, and it went on pretty good. So far after surfing it a fair amount, it still looks pretty good.
If I had the space, I would follow resinhead’s thread and spray it with 2part poly.
My goal is the least amount of effort so I can surf more, sand less
I’m in agreement melikefish less sanding more surfing I don’t sand my epoxy boards except sharp bits from the tape on the rails deck is covered in wax anyhow.
You can sand the hotcoat with 80, thoroughly wipe clean and use a xylene-thinned coat and leave it at that. Looks sort of glossy, and acceptable if it’s your own board and you’re lazy. On curing, I feel that 100F for 24 hours works for producing repeatable sanding results. Simple hot box made of home depot insulation panels duct taped together, $10 heater/fan, and some kind of thermometer. Use it also for drying painted blanks.
I never sand epoxy prior to post curing at 110F (the highest my space heater will hold it) for 24 hours. My laundry room is my baking room. Once you post cure, you’ll get it, and never not bake a board.
