Acrylic window in a trash can

[kbb0118]

I'm going to attempt something a little odd. The purpose is to put together a cheap home for pelagic spawners. Like this (http://www.projectdibs.com/forums/showthread.php?t=2168)

I've asked around (including the owner of above thread) for tips and gotten some good ones along the lines of "if I had to do it over again". Mostly he wished he'd curved the window.

Here's what I came up with so far:

Brute trash can, 32 gallons (22" diameter, 27" tall), Gray
1" uniseals
1/4" thick cast acrylic 18" tall x 12" wide piece
Nylon slotted hex bolts M5-0.8 20mm long with matching nuts (smallparts.com)
Weldon #16 and #4
Aquarium safe silicone

I'm using the trash can because I have an extra one.

I'm going to have to thermoform the acrylic. I wanted to avoid using the kitchen oven but I think it is likely the best way to curve the acrylic. Next best option is a space heater, but that will be a challenge. I have a hot knife and heat gun but neither of those will give me the all-over heating that the oven will.

My plan is to put the acrylic on aluminum foil in the oven at 250 degrees until it gets soft, then use the inside of the trash can (covered in felt) to bend the acrylic to fit the form of the trash can.

I'll cut the trash can (probably with a Dremel) and glue the window inside the can. I will try drilling for the bolts on a few pieces of scrap since I'm not sure how well that will go.

Any other suggestions before I get started?

[patent]

My plan is to put the acrylic on aluminum foil in the oven at 250 degrees until it gets soft, then use the inside of the trash can (covered in felt) to bend the acrylic to fit the form of the trash can.

I did this in fixing a crack in my skimmer body. It was technically easy, but in practice I had a hard time getting the acrylic to match the bend of the skimmer. I'm not terribly satisfied with the result, hope you have better luck, and you may given you are not trying exactly match the trash can body, but rather fill a hole.

Be patient with the temp. If you heat the oven to hot you get bubbling in the acrylic, too cold and it will cool too far before you can properly bend it. I worked up in 10 degree increments, taking it out and trying it a couple times before I got where I wanted.

[Koletang]

I agree, a skimmer needs much more precision than a trash can :)

[Flounder]

I dont think weldon is going to get you anywhere. I'd just use silicone.

[Chad Vossen]

use nylon bolts and gasket material. lots of nylon bolts. silicone doesn't have a very good bond to acrylic, and weldon probably wont bond to the trash can.

[data_loss]

Let us know for sure how the oven thing works out. I did something like this (but smaller) to curve the overflow I build for my corner tank. I used a heat gun and some clamps and 2 hours later it was ugly but functional :)

[SuperDave]

has any one tried poly carbonate acrylic.it's most flexible softer.i think Menards sells it in different sizes .i would use a thin strip where your going to bolt it so that the pressure from the bolts is more spread out and not putting pressure directly on the glass.poly carbonate is softer so it won't crack as easy you could use a thinner sheet then and it would be easier to bend . ace hardware sells nylon nuts and bolts i don't know if that helps

[reeflover]

Dave, I think you are right, polycarbonate would be better. It's a little more expensive, but much tuffer stuff and doesn't scratch easily, nor brake, but it will bend easily. In stead of nylon bolts, I would be inclinded to use stainless steel, then coat the part in contact with the water with silicon glue (even though it is not necessary. Silicon glue will adhere well to polycarbonate, but not well to acrylic or ployethylene. You can abraid the polyethylene for better adhesion. I would probably figure out a way to make a metal support on the outside as a full-length 'washer' to apply even pressure long the polycarbonate sheet so there are no buckles in the silicon gasket where they contact the tank. If this is for your flame angels, you may want to check out this paper for other ideas http://www.library.umaine.edu/theses/pdf/CallanCK2007.pdf

[kbb0118]

I've got some polycarbonate here. It's 0.09" thick tho and that is probably too thin? I've tried drilling that stuff before and it just cracks. Or maybe I'm doing something wrong?

This is for wrasses :biggrin:

[kevlake2005]

Any other suggestions before I get started?

I can't wait to see the outcome!! Did you make some more space in your fish room?

[reeflover]

Kate, here are some tips on drilling polycarbonate

http://answers.yahoo.com/question/index?qid=20081120140223AAyfgNZ

http://www.plasticsmachining.com/magazine/199609/polycarbonate.html

I'd use a water coolant and drill over a 2X4 for support under it. If you get it tight enough, being thin won't matter, because it is tuff stuff. It will hold the water. I would place the window on the inside so the weight of the water pushes the window against the tank to improve the seal like this

http://www.aquaticeco.com/subcategories/3954/The-Mini-Fish-Farm

[kbb0118]

You guys rule! Normally I do a lot of research on my own, but haven't had much time with a 3 month old, 2 year old and 4 year old in tow. I'll see if I can drill some polycarbonate tonight!

[kbb0118]

So I tried the polycarbonate. Got it all drilled, siliconed. It hugs the curve pretty well. I was on the 3rd to last bolt out of 44 and I CRACKED IT! :brick::swear::swear::swear::swear::bawling:

:stupid::stupid::stupid::stupid::stupid::stupid:

Gotta get some more polycarbonate and silicone.... :mad:

[kbb0118]

Deep breath.....

I got the new window installed last night without cracking it! I'll let the silicone cure until it stops smelling. Then I'll drag it outside and fill her up!

[Rafa]

Pix plz?

[reeflover]

Good luck Kate!

[kbb0118]

http://i1103.photobucket.com/albums/g476/Kate_Blanchard/5f8cd004.jpg

http://i1103.photobucket.com/albums/g476/Kate_Blanchard/bec92069.jpg

[reeflover]

Looks good! Almost professional :gay1:, well better than I could have done anyway.

[kbb0118]

I had my doubts that this would work, but she holds water!!

Time to set her up!!

THANKS EVERYONE!

[odie]

So cool!! I dont think anyone asked, but what are going to breed?

[kbb0118]

I'm going to be the first to breed the Mystery Wrasse (note my optimism :biggrin:)

I also have a trio of Melanurus wrasses that will go in here. Someone else has had some spawn, but from what I see, nobody has raised Melanurus wrasses either.

[odie]

That is so cool!