Thread: flawless high-gloss epoxy finish?

If the bubbles are just on the surface, sand away. If they are deep you have to sand back to wood and start over or put them in the giveaway pile and start over.

I think I can offer some advice in regards to the "luster coat" you're trying to achieve. I've done some finished carpentry and floor refinishing in my short years and I've used either a lamb's wool brush (for floors) or foam brush (for furniture). It keeps out brush strokes which can be a problem with final coats. The key is to use a light continuous stroke and not put pressure on the foam otherwise it will sort of squeegie the poly onto the epoxy finish (then you have to take steel wool to it in the case of furniture). Hope this helps.

could you use a heat gun rather than a torch? out of curiosity.

Red

Originally Posted by Big Red

could you use a heat gun rather than a torch? out of curiosity.

Red

Hell I use a BBQ style (long neck) cigarette lighter. Works just fine to help ease the bubbles out right after a pour.

Originally Posted by Big Red

could you use a heat gun rather than a torch? out of curiosity.

Red

You can use a heat gun, but the air may blow dust up and it tends to blow the finish off the scales, tried it once.

ToxIk - the curing problem is probably due to the mix ratio of the epoxy and hardener. Most of the stuff I have seen says to mix by weight rather than by volume - for example 50:1, so if you are only making enough for a few sets of scales you could be weighing out just a few grammes of hardener. Even with weighing-scales accurate to 0.1g, you could introduce a big error, especially if you measure into two separate pots - some of the mixture adheres to the side of the pot and doesn't get introduced into the mix. The only way around this that I have found is to increase the amount you mix - wasteful, but it reduces the magnitude of the error. I also measure both parts into one pot, as I also only do small pours. It helps to drip the accelerator in drop-by-drop while watching the weight readout - you don't want to dump a load of accelerator onto the part A! Wasteful, and potentially a fire hazard!

Another problem with curing is that the chemical reaction releases heat which begins the cure - if the stuff is too thin, not enough heat gets generated, resulting in delayed setting times or even no setting at all. PU under 2mm thick is a pig to set properly! Modellers use a light box to solve this - they fit a couple of 60 watt bulbs into a box, upend this over the workpieces, and leave the lights on for the initial setting time. You don't need much heat - around room temp is ideal. Plus you get dust protection.

In my experience, the latitude for mixing errors with PU is even smaller than for epoxy, although the PUs are quite flexible and nowhere near as brittle as some other acrylics.

Regards,
Neil.

Thanks for the info, Neil. But I'm not having much trouble with the it curing properly, it's just ending up with stuff in the finish. Also, the particular epoxy I have says to mix by volume in a 1:1 ratio. Also FYI, I find that syringes from the drug store work great for measuring

I just tried the polyurethane fix method too. It works well, but again, I'm having issues with flecks of dust getting in the finish even with it drying in a closed box. Before I go any further tinkering with the finishes, I'm going to revamp my curing/drying setup to make it more or less hermetic.

Aaargh - I missed the NOT bit in your first post! That'll teach me to speed-read! The 1:1 ratio sounds great - I looked for that but couldn't find it in PU clear-coat, only in a PU that is an off-cream colour that you are meant to add things to.

I have read of people hanging plastic sheeting in a small room to blank-off carpets, curtains, etc, then wiping everything else down with a tack-rag and letting the dust settle overnight, but that sounds a bit extreme for small volumes!

I'm lucky - I'm a photographer and have a darkroom fitted with a dust filtration unit - I leave that on for an hour or so and all the dust gets filtered out. You can get small units with the filters or small electro-static ones that don't cost too much.

Regards,
Neil

I just cover mine with a shoe box which I've wiped out and is clean for the first 8 hrs. then it is dust proof according to the directions with my epoxy.

We used the Mirror coat on a bar top made out of Australian Cyprus Flooring Material. It leveled ok, but there is this oily looking pattern on it almost like oil mixed in with the mirror coat - you can only see it when you look at it from certain angles, but it is noticeable enough to be a problem i think. Any ideas on what that might be from? We used propane heaters in the area to make sure the room was warm enough...I don't know if it would be from that?