Cementing acrylic - so many bubbles!

  • mneville277
  • mneville277's Avatar Topic Author
  • Offline
  • Fresh Boarder
  • Fresh Boarder
  • Posts: 11
  • Thank you received: 0

mneville277 created the topic: Cementing acrylic - so many bubbles!

No matter what method I use, I get so many bubbles in my seams! Thankfully, I am still working with scraps trying to perfect the technique, but I am running out of patience to see some final results. I am using Tap Plastic's Acrylic Cement and 3/8" polycarbonate (Lexan). Final product will be 1/2" acrylic.

No pressure, relying on capillary flow = looks like foam in the seam
Pins under the piece, waiting 0-30 seconds & no pressure = BIG bubbles, but less of them
If I use pins and apply pressure on the seam, I can eliminate most of the bubbles, but doesn't pressure lead to a weak joint? Plus I get some squeeze-out that creates a ridge at the seam.

Is it possible to prep a piece TOO well? After cutting, they all get run across the jointer, sanded with 220 grit, and scraped. Am I not allowing enough surface texture to take full advantage of the capillary action?

I'm usually a pretty DIY-savvy guy and this one is driving me nuts, but the perfectionist in me won't allow for bubbles. Is this just normal for polycarbonate and won't happen with acrylic? What am I doing wrong?
#188194

Please Log in or Create an account to join the conversation.

  • Posts: 342
  • Thank you received: 12

RIFF-RAFF replied the topic: Re: Cementing acrylic - so many bubbles!

If you want to join acrylic without any bubbles and get a perfect finish you really need to use chloroform.
#188196

Please Log in or Create an account to join the conversation.

  • mneville277
  • mneville277's Avatar Topic Author
  • Offline
  • Fresh Boarder
  • Fresh Boarder
  • Posts: 11
  • Thank you received: 0

mneville277 replied the topic: Re: Cementing acrylic - so many bubbles!

Okay - new theory...

I went back and revisited uarujoey's YouTube videos and Tap Plastic's tutorial videos. In both cases there was less prep work done that I have been doing, but I don't think this is the problem.

I am beginning to think that it is the polycarbonate. The solvent cement is made for acrylic, but am told it should work with polycarbonate - apparently not as well. Does anyone have experience with Lexan welding differently than acrylic?
#188220

Please Log in or Create an account to join the conversation.

  • Posts: 342
  • Thank you received: 12

RIFF-RAFF replied the topic: Re: Cementing acrylic - so many bubbles!

What are you actually trying to make?
I have tried all different types of so called acrylic glue from epoxy based to acetone etc etc etc. Their is hundreds of ways of going about it but the only way for say an underwater camera box or aquarium is chloroform. Once it dries (within seconds) you will be left with an edge you can hit with a hammmer and not even see.
I get mine from the local chemist.
#188228

Please Log in or Create an account to join the conversation.

  • mneville277
  • mneville277's Avatar Topic Author
  • Offline
  • Fresh Boarder
  • Fresh Boarder
  • Posts: 11
  • Thank you received: 0

mneville277 replied the topic: Re: Cementing acrylic - so many bubbles!

Once I get this figured out, I will be building a 45g sump and 120g tank.

The bond I get now is strong, just full of bubbles. Chloroform is a controlled substance in the US, so not readily available nor an option. The properties of chloroform (trichloromethane) and solvent cement (dichloromethane) seem to be the same, save for a shorter working time with chloroform.

I'm really thinking that it may be as simple as the chemical difference between polycarbonate and acrylic. I have an abundance of polycarbonate scrap, which is why I'm practicing with it. I suppose that I'll have to get some cast acrylic to work with and see if I have better luck.
#188233

Please Log in or Create an account to join the conversation.

  • Posts: 1215
  • Thank you received: 9

BENNO replied the topic: Re: Cementing acrylic - so many bubbles!

i was watching a show called tanked and they build custom acrylic tanks
they say bubbles are the cause of edges that are not preped good enough sand
some more get an even edge
#194571

Please Log in or Create an account to join the conversation.

Moderators: Big-KenDRACO
Time to create page: 0.125 seconds