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Cruciform
02-14-04, 07:41 PM
I just got back from buying some acrylic sheets (and more herp books :)) and I was wondering what's the best thing to bond the sheets together to make a vivarium.

I've been looking at Understory's dart frog viv design and figured I'd build one at home. I'll probably go to him for my frogs (good prices and local), but don't want to spend a fortune on a Viv I can make at home in a night or two.

I've got silicon already, but when talking to the paint guy at the Home Depot he suggested getting it from a pet store. Since pet store silicon is more expensive, is it really any different (less toxins?)

He also said contact cements and epoxies (the fumeless ones) would still give off enough poisons to kill fish and amphibians. Before I start sticking the pieces together I want to be sure I'm not signing a death warrant :)

Linds
02-14-04, 10:48 PM
I don't know much about building all-acrylic enlcosures so I won't comment on that. However, pet store silicone is a rip-off. As long as the tube states it is aquarium safe, then you are fine. I just use the big tubes available ffrom Home Hardware that are 2.99 CDN ea. If it doesn't state it is aquarium safe, it may contain additives to stave off mold and mildew, and will also offgas ammonia after it is fully cured. LOL they should change the labelling from 100% silicone to 99.8% or something if they want to do that, pretty misleading :rolleyes:

Cruciform
02-15-04, 12:40 AM
Thought so :) I couldn't envision paying 12.99 for a small tube of silicon.

Stockwell
02-15-04, 12:55 AM
You didn't ask about cutting it, but I thought I'd mention there is a special scriber tool that is used to cut plexi and other laminates. I have several of them and they work fantastically well.
They are made by OLFA and cost less then ten bucks.
You scribe along it with a straight edge, and then repeat, several times, scoring out material as you go.
Once you're about a third through you just apply pressure along the score and it breaks quite easily.
Don't try to cut it with a saw. The heat from friction simply melts the cut and tends to weld it back together as you go. It also makes for very rough edges.
Acrylic(plexiglass) is sometimes bonded with acetone, but there is better and easier to use glues specially made for acrylic. Professional tanks and other industrial items are actually welded using ultrasound. This is superior to glue as it doesn't introduce any foreign glue, but obviously can't be done at home.
If you do an internet search you should have no problem finding companies specializing in plastics.They should be able to recommend the ideal glue for your purposes.
I do occasional business with Alfa and ABC plastics but I'm sure there are lots of them.

Cruciform
02-15-04, 01:44 AM
Thanks for the tips :)
They had the tools in a rack in the middle of the display for 4 bucks so I grabbed one :)

Now all I need to do is focus my subwoofer into an ultrasound cannon :)

Jeff Hathaway
02-15-04, 11:04 AM
Hey Roy,

I used to buy from Alfa too! Other suppliers in the GTA- JJ Downs Industrial Plastics, East-West Plastics, Commercial Plastics, Warehouse Plastics, etc.

Cruciform- I used IPS Weld-On #4 Acrylic Solvent Cement for making our rack shelves. It works great, but don't breathe the fumes too much. Once cured, no worries about it. Although I haven't tested it, the joints may well be stronger than the sheet material if done well. Definitely don't use silicone. Also, there are saw blades designed for cutting it, which can be useful if the material is thick.

Jeff Hathaway
Sciensational Sssnakes!!

Invictus
02-15-04, 12:05 PM
Not all "Aquarium safe" silicones will state that on the packaging. The ones that do are also a rip-off, as are the ones in the pet stores. As long as it is 100% rubber silicone, it's safe. It will offgas like hell for about 2 days, but after it reaches full cure, it's perfectly safe. I use clear silicone for my cages.

Stockwell
02-15-04, 03:17 PM
I've used every kind of silicone , including the colored stuff and the bath tub stuff... I've used the acrylic calk as well. I know some might disgree but I think it's all OK for simply sealing up cracks for terrestrial herps. I think sometimes we can be a little too worried about things.
There is a difference between whether you're simply sealing joints in a snake cage or making a fish tank that will actually hold fish or amphibians. In cases where herps and fish will actually be in water, then I think that is much more critical in regard to sealant contamination

But in regard to this post and making an enclosure entirely out of acrylic, I agree with Jeff.
Don't use silicone..get the right acrylic glue.

Linds
02-15-04, 06:42 PM
Originally posted by Invictus
Not all "Aquarium safe" silicones will state that on the packaging. The ones that do are also a rip-off, as are the ones in the pet stores. As long as it is 100% rubber silicone, it's safe. It will offgas like hell for about 2 days, but after it reaches full cure, it's perfectly safe. I use clear silicone for my cages.

Actually most of the stuff labelled 100% contains other potentially hazardous additives (as I mentioned above), and will continue to offgas ammonia after it is fully cured. This information is straight from GE (nobody knows that stuff better than the poeple that make it :p), I phoned them last year in regards to their sealants. The stuff I use is aquarium safe and is actually the cheapest I have seen any type of silicone go for @ 2.99 for the big (gun) tubes.

Desert Ambush
02-29-04, 10:37 PM
To weld two pieces of acrylic there is nothing better than methylene chloride and you can get a full gallon for less than 20.00$ can. The fumes are strong but they fade out real fast usually in an hour after you applied the stuff. You can get the MC in most plastic shops and companies.

KarlSnake
02-29-04, 11:23 PM
Acetone will sorta weld Plexiglas®, Lucite®, Perspex® or other polymethacrylate acrylic plastics, but the joints will always be bubbly (this gets worse with time) & not very strong, either. MC - methylene chloride - dichloromethane is cheap & very effective. Be sure the edges are smooth to begin with as the thinner the bond line the better. It will chill itself down below the local dew point & fog up (forever) if the humidity is too high. DON'T blow on it to "help it dry"! Best to polish the edges / bond line, apply just a little bit of MC, then (at one go, there is NO going back), press the edges / bond line together & hold or clamp overnight. You can also set up your joints with clamps, weights, or whatever, then CAREFULLY run an eyedropper of MC along the bond line & let it wick on into it. BTW, MC is rather not good for you, so please be very careful - if you can smell it, you are above the hazardous concentration.

There are way too many different kinds of silicone adhesives. The best for continuous water immersion is GE RTV #108 - stinks like a mashed vinegaroon until it cures, but it will hold up well for terraria or aquaria. Other silicones use other (non-acetic-acid) curing systems - some acid, some alkali / base / amine / ammonia - some metallic / platinum. All of 'em quit being even potentially toxic when they quit stinking &/or tasting bad. Some silicones will require a "primer" & some just for some substrates. You gotta read the labels. Hit the Internet & have a looksee @ the manufacturer's product information. Pet store just about anything is a rip-off, especially their silicones.

If you can find it locally, the GE Silicones stuff is the best.

Cruciform
07-16-04, 11:25 AM
I finally found a place in London to buy acrylic and methylene chloride :) :) :)

People would always recommend Cadillac Plastic, but for some reason they're not in the yellow pages, regular phone book, or in Bell's online database.

But Parker Plastics, at 486 Clarke Side Road (just north of Dundas, across the rail road tracks, on the right) has it.

The MC is either sold by the gallon, or in an applicator tube, or you can bring your own container. An applicator of methylene chloride is about 4 oz. for 10 bucks. The savings are better if you buy the gallon (around 30 to 40 bucks) or bring your own container, because the applicator costs a few bucks.

Storage should be in a metal, sealed can. According to one of the staff, keeping it in a glass jar will end up with it evaporating in about 3 weeks.

To prevent evaporation store it in a fridge or cold room -- but not one with food! :)

Anyway, now I can get to work on my gecko and frog vivs, and a display case. Woot! :)