HOW TO: glue acrylic (welding)

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A closer look at using Weld-on Acrylic cement. Weld-on 4 and Weld-on 16 are featured as the two cements that i use to build an acrylic aquarium.

You will need these two cements to build an acrylic aquarium, like the one seen here:


The king of DIY


What do you think?


Written by The king of DIY

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  1. I can usually obtain enough solvent in the bottle for a reasonable sized job by simply squeezing the bottle a bit (displacing air), then inserting the "needle" of the upside down bottle into the solvent and slowly releasing the squeeze on the bottle.
    By reasonable sized job I mean enough so that I don't lose too much solvent due to evaporation while having to reopen and squeszing the solvent from the bottle back into the storage canister.

  2. To get the solvent into the bottle without using a syringe, you can put all the pieces of the plastic bottle together, squeeze it (making sure its empty, of course), dip the tip into the bottle, let go/unsqueeze the bottle and the solvent will draw itself in.

  3. I want to seal a crack in the plastic window in my van. Can I do that with 16? Want to seal it from rain and fuse the hairline crack between the pieces without removing it from the frame. Window is a skylight window (flat) at a 45 degree angle.

  4. Thanks for the great VID's Joey. I am completing my first build. Please can you point me to the VID where you demonstrate how to remove unwanted WeldOne 4 stains?

  5. Hi! Do you have a recommendation for gluing mirrored acrylic? I have tried an epoxy glue as it doesn’t seem to eat away the mirrored backing but it doesn’t grab on as well and I’ve had parts come apart. Thank you!

  6. Joey, or anyone else who has cemented acrylic successfully: On the four brand new sheets I will be using, each one has a sort of "lip" on the longest edge. While all sides are perfectly square/straight/gapless, do I need to prepare that one side by softly sanding it down. I can provide pictures incase I'm not making too much sense. Thanks!

  7. Great video. For anyone having a hard time sourcing Weld-On 4 (the stuff is not only expensive, but hard to find), it can be substituted by pretty much any dichloromethane (methylene chloride) based solvent. Many paint strippers (but not all) found at the hardware store contain 60%+ dichloromethane and will work just as well. Just go to the manufacturer's website and check the MSDS for composition. I've tried Recochem's Heirloom paint stripper. Works perfect and costs about half the price of Weld-on 4.

  8. Hi got to the point where I have sourced my acrylic supplier and waiting to receive the can of Weldon 4. I have a doubt… How do you deal with spills? Outside, I can't see a big deal, specially if you plan to use a router to round the edges (and then polish) but on the inside, how do you deal with the extra that comes out once you clamp it down? Thanks

  9. My acrylic joint did not make a clear weld… what can I do? I tried for a long time to get all the saw marks off with my scraper but it did not quite work. What can I do? Is the seal going to work even though its foggy? I have weldon 16 and 4



HOW TO: Build An Aquarium 4/6

HOW TO: Build An Aquarium 5/6