building an overflow

[mister crabs]

going to build an overflow this week and figured i would use black acrylic and dremel the teeth into the top. but I have never worked with acrylic before so what do i need to glue it together? and which acrylic os safe for aquariums? I heard one of the GE silicons but unsure if it was I or II. all help appreciated!

[impur]

Weldon to glue it together. You could get away with using 100% silicon since the water pressure will help keep it together. Doesn't matter what brand silicon, as long as its 100% silicon.

[andy]

Jeez, I dunno about using silicon. It has a little more than zero holding strength on acrylic. Get some Weldon; TAP Plastics and Parkrose Hardware have it, as should any decent hardware store. Do you know anyone with a router? That'd do a nicer job on the overflow teeth.

[impur]

My AGA megaflow overflow is held on by silicon.

 

I found that if you scuff the acrylic where you will be applying the silicon it holds better.

[Ronjunior]

Personally, I like to do things right the first time...not that I always do, but I'd suggest using a product that is made for it so there's no DOH! factor.

As for silicone, if the product is mildue resistant, it likely has the additive that is not supposed to be fish friendly. Check the MSDS sheets on the mfg. site, it lists all ingredients of a product.

Article below on gluing acrylic and types of glue.

http://ozreef.org/diy_plans/techniques/gluing_acrylic.html

[Nyles]

You should use a router or table saw to make those overflow teeth. If you use a dremel odds are it will look like a homemade haircut, its the little things that count when doing DIY. If your using a table saw get a dado blade or stack blades so you can do it thicker than single blade width. They come in real handy on all kinds of projects.

[mister crabs]

ok so the GE silicone that DOESNT have the mildew additive is what i want. would HD carry the weldon? which #? and what thickness of acrylic should i use?

[andy]

HD doesn't carry Weld-On; it's a industrial-type adhesive and is pretty nasty stuff. Evidently, California illegalized one of the formulae (#4?) and now it is almost impossible to get (TAP portland stopped stocking it).

 

1/4" would be fine, TAP usually has enough to make a couple of overflows in their scraps bin. At a dollar a pound for scraps, figure $2

 

And if you are going to use a Dremel to cut the teeth, try making a template out of thick cardboard (cut it out with an x-acto knife) then follow that with the cutter. You should end up with better spacing and straighter cuts.

 

EDIT: Also, I've found that an eye-dropper is a much easier way to apply the glue to the joint. Those little bottles with the needle applicator just don't cut it, they dispense so little glue that it evaporates before it actually gets anywhere. You have to be careful you don't flood the work, but at least you get a reliable joint. TAP sells eyedroppers that aren't affected by Weld-On.

[mister crabs]

where is tap located at?

[H20cooled]

http://www.tapplastics.com/

 

Don't use silicon to build the overflow, it will not hold it together and it will look like garbage. Get some weldon 4 or 16, you can sometimes find the 16 @ Ace Hardware stores. You can use silicon to attach the built overflow to the glass though.

[pledosophy]

I got Weldon 4 today at Tap plastics. Also got precut acrylic for the sizes I needed for my overflow I am building. Total for acrylic, applicator and Weldon was like $16 and change.

 

IME if you go slow with the dremel the teeth come out fine.

[R-3]

GE#1 works fine on attaching acrylic to glass. Scuff it up like Miles said. One thing that you have to realize is that the weight of the water against it is gonna hold it. After siliconing mine in on my 90 I tugged on it pretty good and it didnt budge. Just make sure like everyone else says to get the 100% GE#1 Silicone w/o the mildew resistant crap. Good luck! Later Ryan

[R-3]

Hey I forgot to add that I have some black acrylic, GE#1, and some sand that I could make a great package deal for ya! Let me know. Later Ryan

[mister crabs]

ok....how much is great package deal? lol pm me.