solvent welding corian type stuff? - Page 1
Forum section: electronics / general

author: coppercone2
author_rank: Super Contributor
timestamp: April 05, 2020, 09:43:18 pm
content: Is it possible? I managed to get something that looks like the beginning of a joint with SC-325 (THF+MC mix).Is there some kind of combination that will make it (for a frame that holds up a tank). I shudder at buying a glue gun and storing more exotic epoxy types.I think the SC-325 will be strong enough, especially when its clamped hard.. at least for bonding corian to something that is called 100% acrylic (some kind of counter top material).I really don't want to buy the acrylic epoxy from 3m. Infact a epoxy just went off and smelled up my tool box (the resin offgasses for no reason at all and spilled).My weld area big enough, and the forces are so low, that it looks like the joint that was formed might just be strong enough to work, or at least not fail catastrophically (expect a seam to appear that can be filled if it does happen, at the expense of like 60$+)Good luck with acrylic and polycarbonate so far, using SC325 and weldon#4, which should store very well for a long time because they are solvent based.. so long the container is good.Otherwise i need to make a whole bunch of back burner shit to make use of all the epoxy, if you must buy the fucking epoxyThese are just support frames for etch tanks, that probobly don't need them, but the material was on hand so I built them, and they even look nice..I actually think the corian like material + whatever this stuff that said something along the lines of (100% acrylic) bonds well with Sc325, but it totally failed on the corian+corian bond (which was made by accident, it happens to be that my frame so far is made of dissimilar materials, due to availability.Never ran into something that worked better because dissimilar materials are being bonded (by happenstance) before.

author: KL27x
author_rank: Super Contributor
timestamp: April 05, 2020, 10:47:50 pm
content: ABS solvent welds the best of anything I have used. ABS to ABS. ABS to acrylic. ABS likes to be solvent welded and the joints last years without cracking.For my etch tank frame, I used nylon bolts and nuts. The frame is plywood. The frame holds the acrylic pieces together to keep the silicone seams under constant pressure.

author: coppercone2
author_rank: Super Contributor
timestamp: April 05, 2020, 10:57:17 pm
content: well that joint failed completely. I will try superglue now. It just fell apart, but it was strong enough to be picked up despite being long (its like 20x20 inches or so)the etch tank is welded with the solvents with clear material, I just want something to put this into (caddy) that is heavy. It's just a frame and base that you insert the tank into (I glued rubber to the tank walls exterior for slip resistance and some armor). It has no leak problem so far.This corian stuff just does not wanna solvent weld at all.. some people say its only 30% acrylic and its not enough bond strengh, which seems to be true. It seems that the solvent containing THF is better then the methylacrate containing one, but its just too weak after 2 hours to be useful.the tank is like an insert (think hard drive caddy). The idea being I can take it out and wipe everything down after I drain the tank, or wash it out right if there is a leak. I thought about just welding everything together to make it huge but if there is a pump problem or crack in acrylic, its modular now.If it holds together I might drill holes and epoxy metal pins into it to make it sturdier (have my doubts about super glue too). Otherwise you need 3M 810 adhesive (40$ for a cartridge and another 30$ for the gun).The clear material actually seems to weld together very well with the Weldon#40 solvent, the polycarbonate smaller tank welded with the 325 solvent required rework after leak testing however.. the material is stronger and better but it does not form the best seals with the same cut quality (possibly a burr was left after cutting that acted as a gap).

author: KL27x
author_rank: Super Contributor
timestamp: April 05, 2020, 11:03:58 pm
content: ^ Good luck with your tank not leaking.That thin plexi does not like to be welded. Good call on the support frame, and it better be good.Odd that it's good enough for 300 gallon fish tanks. I think the thickness of the weld is why it works for that. If I were to try solvent welding an etch tank (a third time), I might try putting acylic windows into an ABS tank. Perhaps use acrylic for the front and back and ABS for the middle piece sandwiched between the two.But I made the silicone and bolted tank to last a lifetime; and I think it might get there.My solvent-welded tanks didn't catastrophically fail. They just developed pin hole leaks after a month or two.

author: coppercone2
author_rank: Super Contributor
timestamp: April 05, 2020, 11:05:51 pm
content: I have not tested it with ferric chloride yet, do you think the acrylic joint will be attacked by it? I thought it was welded and essentially solid at this point, besides the bubbles.How hot do you run the etch at?The previous tank I used was found in a dumpster, believe it was a potted plant experiment.. I also think it was super glued (I tried to repair it recently, with the same solvents.. and it did not hold AT ALL, leading me to believe there was some kind of other glue layer on it blocking the solvents from fusing the seams. It cracked because I got mad and slapped a heater on the side when I was having process problems, and it got really hot, so I think it expanded and cracked the joint after.

author: coppercone2
author_rank: Super Contributor
timestamp: April 05, 2020, 11:09:00 pm
content: for the leak test I just filled it with water and left it on a colored paper towel for a long time to see if there was any drip.. did not see anything. I believe the formation of bubbles indicates that there was material migration, so it should be solid. I thought it was good so long there are nice round bubbles.

author: coppercone2
author_rank: Super Contributor
timestamp: April 05, 2020, 11:13:06 pm
content: and yes, there is alot of cracking on the material, probobly because its thin.. but they don't leak.. I just poured more glue on it after lol.. its probobly unstable

author: KL27x
author_rank: Super Contributor
timestamp: April 05, 2020, 11:19:32 pm
content: I was just editing my last post. Basically, my solvent-welded tanks were fine at first but developed pin hole leaks. In warm weather, salt would grow at this (these) spots. In colder weather, a drop or 2 of liquid would form and slide to the bottom of the tank. Nothing major, but this bothered me, and I like to leave my tank filled all the time.I would keep a heater the heck away from thin plexiglass solvent welded joints. Dunno how big your tank is, but I would want it at least 3/4" away from the walls. Maybe more.My tank is only 3/4" wide on the interior; I don't use a heater, at all. Even in colder weather, it just takes longer. If you use ferric, over-etching is not a problem. So just set it and forget it for awhile.Dunno what kind of "more glue" you just poured on it. I don't think adding more solvent will help. Those microcracks are why your tank will eventually leak. You mentioned you scored some ~ 3/16's acrylic in another post from 5 months ago? Unless you did something to make your joints way bigger than that, I would bet dollars to donuts your tank will eventually leak from stress cracks. I don't think the ferric has anything to do with it.I poured epoxy resin into the seams on these welded tanks, and it stopped the leak for just another couple months before completely failing, starting to peel off.

author: coppercone2
author_rank: Super Contributor
timestamp: April 05, 2020, 11:26:40 pm
content: i have a perestalic pump and I don't want to leave it in the tank for too long. Oh right, the other thing is acrylic comes in different grades, you are supposed to actually anneel it after you cut it I think.. but the procedure is complicated. I assume the stuff I have is junk. AFAIK the cheap stuff they just pour and cool, the better stuff you cut it in the shapes that you need a bake it in soak cycles that seem to be industry secrets.

author: cvanc
author_rank: Frequent Contributor
timestamp: April 06, 2020, 12:33:02 am
content: HTHhttps://www.corian.com/IMG/pdf/k-27477-dupont-joint-adhesive-general-information-2.pdf

author: coppercone2
author_rank: Super Contributor
timestamp: April 06, 2020, 12:53:11 am
content: Quote from: cvanc on April 06, 2020, 12:33:02 am50$ nasty 2 component acrylic epoxy I think. That's if you are die hard with glues. I almost bought it but decided super glue + pins.Do you know if the epoxy glue guns are industry standard, or do they have their own standards? I also am scared to buy a 3M glue mixer gun and then find out the mixers and gun does not fit other epoxy cartridges.If the gun was universal MAYBE.Like my glue manufacturers of choice would be like 3M, Dupont.. then you also need 2 caulk guns for both sizes (preferably electric caulk guns).Heft price + hefty storage requirement. Wish it was magnetic and you can weld it with a torch.The acrylic/polycarbonate cement is a PLEASURE to use. You just cut, align and squeeze it in with the little bottle. It's like the best gluing operation.. its even easier then double sided table because you don't need to align anything or even worry too much about touching stuff, since you are doing edges you don't need gloves if you use the bottle carefully and just wipe it down with alcohol. Let alone getting tape stuck on your gloves. So long you have a flat table (saw), its totally a hamfisted operation. Only thing that comes close to being as easy is a super glue pen (yes, I like them). heavy clean table you can even open the bottle without spilling itSeriously, is there a easier way to join things (of course, the work you do before hand is hard I guess since it needs to be square/flat). I think the only thing that can mess it up is bad table.. so I recommend you get a heavy ass shop table or use a saw. You can even inspect the weld joint since its clear!Other then it not being clear, this is the main reason I wanted to be able to solvent weld this stuff.. nothing to squeeze out or any wipe downs or other BS

author: coppercone2
author_rank: Super Contributor
timestamp: April 06, 2020, 01:54:37 am
content: superglue worked great