Epoxy resin for puzzle

January 28, 2019 8:14 AM

I have a big puzzle and want to encase it in epoxy resin. Any tips on how to do this?

I've never worked with epoxy before, and I didn't manage to find any tutorial that would help with this.

I'd like to end up with an object that is just the puzzle encased in the resin, no frame, just a layer of resin on the facing side and a thinner one on the underside, for protection. The idea is to end up with a big surface (the puzzle is rather big), a bit like a huge tablemat/ tabletop. I'd like the edges to be clean, clear, smooth resin.

How do I achieve that? Do I need to build a frame and a bottom? If I don't use a frame, can the resin be cut before it is dry, so that I neaten the edges if I pour the resin with no frame? Anything else I need to know? And how much resin do I need for a puzzle that is 1.40 x 1?

Thanks for any pointers.

posted by doggod to Grab Bag (13 answers total)

Best answer: You definitely need a frame, otherwise you'll have a big mess, the stuff is essentially liquid. You'll want to pour the thin bottom layer first, allow that to dry, place your jigsaw and then pour the rest.

I've seen pros use a blowtorch to reduce bubbles, although I've never tried it. I would definitely do a small practice run first!

You'll still have to sand the edges to smooth them most likely and you really don't want to breath that dust in. Make sure you have appropriate masks for this.
posted by stillnocturnal at 8:58 AM on January 28, 2019

Best answer: Search on YouTube for "epoxy bar tops" or similar.

Epoxy doesn't dry. It's a chemical reaction that cures. Please read up on using epoxy. The reaction can create huge amounts of heat and it's easy to burn yourself if you don't follow best practices. Very common rookie move to mix up a big batch, in a tall container, and then have that whole thing kick off in your hand. Sometimes it's annoying, but it can also maim you.
posted by humboldt32 at 9:12 AM on January 28, 2019 [3 favorites]

Best answer: Practice.

No really, epoxy is easy, getting it just right is hard. On a large surface epoxy paint has a process call tippling, using a dry very high quality brush to lightly pop the bubbles just as it's rolled out. Two person effort. Three if more than one batch of epoxy needs to be mixed during the pour. Not sure if it's an exact correspondence but bubbles are the bane.

Also do take care a mixed tub can get very hot.

Also cover the work area more completely than ever, it's sticky stuff and once tacky hard to clean up, two layers of gloves so the outer can be pulled off without a break.
posted by sammyo at 9:19 AM on January 28, 2019

Best answer: These guys seem to have a how-to on doing exactly what you want to, unless I misunderstood something. I had expected it to be a bubbly mess because of all of the little cracks between the pieces but it seems like they did it with "only" a blowtorch to help out.
posted by range at 9:30 AM on January 28, 2019

Best answer: How about this?
Spread a layer of long acting epoxy on a sheet of plexiglass that is larger than the puzzle. assemble puzzle to plexiglass. The plexiglass will give the assembly more strengh than epoxy alone.
Build some type of frame that is larger than the puzzle. Glue to plexiglass.
Pour epoxy onto puzzle to desired depth.
When hardened, cut epoxy on edges to size, with tablesaw or jigsaw.
Sand and polish edges.

Make sure epoxy is clear, many epoxys turn out yellow.
Cutting epoxy may make it gummy and clog your saw.
posted by H21 at 10:03 AM on January 28, 2019 [1 favorite]

Best answer: I recommend using artresin - it's non-toxic unlike many formulations. They have lots of how-to videos on the site but key things - you want to have some sort of a frame to contain it because it will leak and make a mess otherwise. It's good to use a torch to get rid of the bubbles. A gallon (half each - it's a two part product) will cover 64 square feet 1/8" deep - you need to do successive pours if you want more depth for it to cure well. There's a calculator on the website to help you figure out just how much you need.

I have built frames to do a pour around something - alternatively you could sit the puzzle on something and let it drop over the edges - wear gloves and wipe the edges to have a cleaner finish. It's quite sandable once cured but do wear a dust mask when sanding. I'd suggest doing something little first as a practice run - it's not hard but it is picky and you'll get a better sense of how it behaves on something smaller. Use a plastic dropsheet and have good margins to make sure it doesn't make a mess - oh and make sure it's level before you pour!
posted by leslies at 10:03 AM on January 28, 2019 [2 favorites]

Response by poster: Thanks a lot, really great info! Seems like Artresin is the way to go - doesn't seem to be flammable, and the spontanous combustion thing was having me in a tizzy.

Quick follow-up question: can I use a hair dryer instead of a blowtorch? The only tools I've got are a hammer and a few crooked nails...
posted by doggod at 10:57 AM on January 28, 2019

Best answer: I don't know if a hair dryer will get hot enough; but I'd also caution against the blowtorch (or use it carefully): when I did this, the blowtorch ended up "cooking" the portion I was trying to use it on. Heat gun seemed to be the happy medium (or carefully popping them as mentioned).
posted by booooooze at 11:45 AM on January 28, 2019

Best answer: One of the other how-to videos on the art resin YouTube site used a stick lighter like the kind to light a fireplace. Did the trick. Bubbles all gone.
posted by AugustWest at 11:52 AM on January 28, 2019

Best answer: I use a culinary torch but I use torches in my work all the time. Doubt a blow dryer would work - main thing with the torch is to keep it moving and not get too close. I work with resin a lot and have had not issues with torch igniting things or getting toxic - trick is to use it briefly just sweeping across the surface.
posted by leslies at 12:45 PM on January 28, 2019 [2 favorites]

Best answer: Yes, a matchlight type of lighter will pop the bubbles. I've stuck the flame right into the bubbles with no ill effects.
( I occasionally use resin to make jewelry, nothing quite as big as a jigsaw puzzle...)
posted by sarajane at 12:46 PM on January 28, 2019

Best answer: In my experience, epoxies start out clear, and yellow as they age. If you want this to last 'forever', I'd suggest you check this out carefully, as you will be investing a fair bit of effort into making it.
posted by GeeEmm at 1:27 PM on January 28, 2019 [1 favorite]

Best answer: Artresin is still an epoxy and will still generate heat as it cures. (I would also be leery of the "non toxic" billing, my understanding is that all epoxies are toxic.) The bigger the batch, the more heat it will make and the faster it will cure. They can spontaneously combust; I've seen it happen with a quart-sized batch of the stuff. It will happen quicker than you think, because you get a runaway effect of curing > heat > faster curing > more heat > faster curing > more heat > faster > more > fire!

Also a big batch of epoxy is a terrible thing to spill all over yourself, ask me how I know.

It's easy stuff to work with but do give it some respect.
posted by Anticipation Of A New Lover's Arrival, The at 3:21 AM on January 29, 2019 [1 favorite]