diy acrylic overflow on glass?

[sleasia]

I followed everyone's advice and successfully drilled my glass tank :cheer: Now the next hurdle is the internal overflow box. I know I can route sheet acrylic....I'm not too confident about routing sheet glass. Can I bend a sheet of acrylic after I rout the teeth and weld it to the tank wall? Or is welding acrylic to glass a no no. someone mentioned in one of the threads that you crazy glue the acrylic first to the glass and then silicone over it. does this hold well enough? what should I do? here's what I have ...a hole for 2" bulkhead (drain) and a hole for 1" bulkhead (return). the return can come up through the over flow, or on the side...but will be better going up through the overflow.

 

[crox]

I heard that you can't glue acrylic to glass. Why aren't making the overflow all glass and have an acrylic cover going around it?

 

[crox]

BTW how big is that tank?

 

[bojik]

most overflow kits i've seen are plasic of some sort and they siliconed in.

 

[gsd]

Silicone is fine to secure an overflow in, or better yet get some polyurethan adhesive or sealant such as is used in the marine (Boat) industry. Silicone just doe nsot adhere good to plexi but polyurethane does adhere very well and also adheres well to glass. For sometihng internal as such I would not be concerned as it will hold it there with just silicone, but it wold be a hazzard to use silicone to assemble say a acrylic tank, as it wil not hold. Water pressure is going to help hold the parts inplace as well.

 

[acrylic51]

Yeah like mentioned earlier you would use silicone to adhere the overflow box to the tank....To make the internal overflow just route your teeth and then bend the acrylic where you need it bent.....If your unsure of a good method to route teeth in acrylic check out melevsreef dot com and he has alot of good pointers to help you out

 

[sleasia]

someone said you can crazy glue the acrylic overflow to the glass tank first and then silicone over it? Can you? Or should I just use two pieces of glass? I just want to do something I can manage to do and that will not leak. don't most of the glass tanks which are drilled have plastic internal overflows?
I will show pics tomarrow of two other ideas. one just making a standing drain from pvc pipe (not attractive, but probably the easiest for me to do), and the other drilling a hole in a tall rectangular glass vase to use as the overflow, and putting the bulkhead through both the vase and tank wall...this would require cutting teeth in the vase .

 

[sleasia]

the tank is 24w x 20hx 72l...so around 150 gallons I guess. someone at work forced their husband to dump it..it was sitting empty in the basement for 3 years or so...

 

[sleasia]

If you all think the polyurethane works well, I will get some and try. should I crazy glue first?

 

[sleasia]

they categorize gorilla glue, found almost anywhere as a polyurethane glue...is this good enough?

 

[acrylic51]

I've experimented with crazy glue on acrylic and it doesn't bond very well.......If your attaching acrylic to glass you want to use silicone, if your bonding acrylic to acrylic you would want to use weldon

 

[bojik]

to get your teeth get a tablesaw push guide(the kind thats fits in the grooves of the table top) with a clamp and raise the blade Keep in mind to have a sacraficial peice of scrap wood behind it, prefferabley hardwood.

 

[sleasia]

You guys cut the teeth with table saws? won't that crack the acrylic...?
well so far here are my choices...practice runs to see what to do. first, a simple standing drain idea. second a glass vase for an overflow. third (the one I prefer if I can get it to glue properly) the acrylic overflow...a sheet of acrylic warmed with an acetalene torch and bent over a straight edge....

 

[sleasia]

I ordered a piece of black tinted acrylic to use in the final overflow so that the pvc pipes are more hidden. on this practice one, I cut the teeth with a dremel and a cutting bit. I am having a hard time getting nice clean cuts. this probably doesn't matter a whole lot with the teeth, but would help make a better seal if the cut is straighter on the sides which need to be glued to the tank wall. what are you cutting straight edges with on acrylic to get such clean cuts? I don't have a table saw anymore. I have a sabre saw, (like a jig), a circular saw, a miter saw, or the dremel. :notsure:

 

[sleasia]

this is what I mean by my bad cutting.

 

[sleasia]

Ok...I read melev's reef and see how he is doing it with the router. I think I will try this method. I tried using a router, but in a router table, sliding the plastic through the router blade and this didn't work too well. I guess I have to do it the other way around with the plastic stationary and the router moving through the plastic ....I'll try this tomarrow. thanks all.
by the way, bending the plastic with the torch worked really well. I got a few bubbles but nothing that was a problem.

 

[sleasia]

ok!!! Now I'm getting clean cuts with the router...! :cheer: I have to wait until my black tinted piece of acrylic gets here...then do my real piece, glue it in with the polyurethane glue or silicon glue...wait a few days and test....I'll post pics when the final is done. Thanks so much everyone for all your help...

 

[bojik]

cool reason i suggested a table saw is it works nice to cut it. and if you brace it with a backer board relatively easy to do. But yo useem to have figured how to do it with a router wish i could mill some plastics like that (not messed with heating and shaping yet)

 

[sleasia]

I think the problem I had with the router is when you have the router on the router table and feed the plastic through, the plastic wobbles too much. the other way around you can brace down and secure the plastic and this way the router (when hand held) works much better and cuts perfectly clean.....the bending was no problem...I drew a line on the acrylic sheet with oil pencil and heated it with the acetalene torch (I think that is what it is...the ones with a nozzle you attach to a small tank for doing copper pipes). I held the flame up above the plastic about 3-5 inches so as not to burn it and went back and forth along the line heating it for about 5 minutes. I had placed the sheet on a table edge with the line right at the edge and when it is soft enough it just begins to droop a bit over the edge....or it might just begin to form a few bubbles. then I grabbed a rag to hold the heated end of the sheet and pressed it down over the table edge (using that as my straight edge for bending). hold in place about 5 minutes and let cool. easy. I thought it was going to be a big ordeal...wrong. When I get the tinted piece of acrylic I will try and film the bending part.

 

[bojik]

Originally Posted by sleasia
I think the problem I had with the router is when you have the router on the router table and feed the plastic through, the plastic wobbles too much. the other way around you can brace down and secure the plastic and this way the router (when hand held) works much better and cuts perfectly clean.....the bending was no problem...I drew a line on the acrylic sheet with oil pencil and heated it with the acetalene torch (I think that is what it is...the ones with a nozzle you attach to a small tank for doing copper pipes). I held the flame up above the plastic about 3-5 inches so as not to burn it and went back and forth along the line heating it for about 5 minutes. I had placed the sheet on a table edge with the line right at the edge and when it is soft enough it just begins to droop a bit over the edge....or it might just begin to form a few bubbles. then I grabbed a rag to hold the heated end of the sheet and pressed it down over the table edge (using that as my straight edge for bending). hold in place about 5 minutes and let cool. easy. I thought it was going to be a big ordeal...wrong. When I get the tinted piece of acrylic I will try and film the bending part.
Some of those are propane/butane

Sounds easy enough. The vid would be cool to see.