big acrylic tanks

ctel · 01-02-2003, 05:47 PM

i was woundering from some of you guys with big acrylic tanks could help me. After checking on cast acrylic i found that a tank thats 2' 2' 8' would only cost me about $350.00. I've done lots of little stuff with acrylic but not like this. So what i'm asking is after you use weld on #3 and then #16, do your tanks have anouther form of joint compound or lots of cross members. Maybe you guys wound'nt mind sending a couple of pics, i'd love to see your tanks anyway
almost forgot how thick are your tanks too
thanks alot for the help

hamburglar · 01-02-2003, 08:21 PM

That actually sounds a little cheap to me. I've seen two 8-foot tanks lately in my area.

The first is a 240 gallon constructed with 1/2 inch thick acrylic all around. The second was a 300 gallon with 3/4 inch all around. both of these tanks had a full sheet on top with cut-outs to put your hands into the tank.

The 3/4 inch acrylic may sound like overkill on the 300, but the center still bowed out a little over 1/2 inch when filled with water. It was also all that 5 of us could do to get it into the house

ctel · 01-02-2003, 08:37 PM

i thought it was cheap to, but i just got my materals for a mangrove tank 24" 12" 96" with a 3/4 top frame and it cost $132.00. when i got these i had anoughter qoute but i did forget the top frame and im thinking of going 30" tall. I just dont know if i should find a silicone or just weld on #40 for all my seals, after it's put togehter that is

Harpo · 01-02-2003, 08:57 PM

If the liquid weld is applied propperly, you should not need the silicone.
Ours, is a 240gal. acrylic. There is no need for crossmembers, the top should give you all your support, as long as you are using a one piece top that joins the sides 160 deg.
Our 240gl. replaced the 300gl. we had before. The 300gl. was an all glass that broke within 6 weeks of having it. It took 10 men to carry the all glass in, and only my son and I to cary in the 240.

Harpo

ctel · 01-02-2003, 09:18 PM

thats the nicest part of acrylic, lite wieght. but could you describe what you mean by 160 deg, are you talking about the beville on the edge. Sorry to hear about 300 gal, must have been a sad when it broke.

big t · 01-02-2003, 10:17 PM

Ctel,
I was just wondering if you are getting all your suppilys local, or are they from a online vendor? Thanks
tom

ctel · 01-03-2003, 11:40 AM

ya im getting every thing locally, no shipping and they cut it to size.

mojoreef · 01-03-2003, 03:37 PM

Ctel I would go with 3/4 inch for sure, exspecially if you are going 30 inches. This will take care of any bowing problem. I will take with my friend (a custom builder) and find out what he uses for weld-on, but I will tell you that is the only way to go. I wouold not go with a full tank top with just cutouts, that is what most builders uses to do so they could cheap out on the thickness of the walls. Instead go with what is called euro bracing (a 1 1/2 thick acrylic brace that is about 2 inches wide) this coupled with 2 center braces (only 3 inches wide) will be more than enough to brace the tank and allow you complete access to the tank, and not to have to worry about cleaning salt creep of the top plate. the bacing can be made from glueing 2 peices of 3/4 material together. Your pricing on material sounds about right for that size of tank.

good luck

Mike

ctel · 01-03-2003, 04:13 PM

mike are saying run 1 1/2 frame around the hole top and then the two braces,if so this does sound like a much cleaner idea to me and very strong.
Thanks for the input, corey

mojoreef · 01-03-2003, 04:29 PM

Ctel here are a couple of pics, hopefully they will give you a visual on what I was talking about.
the first shows you the euro bracing and how it opens up the top of the tank, this one is 6 feet and only has one center brace.

And this one is a little closer and also shows the coast to coast overflow

wanareef · 01-03-2003, 06:19 PM

ctel

Checkout RC in the DIY-Acrylicman. You can build a 72" x 24" x 34" using 1/2" polycast ( my project). Use the pin method to glue, there is a certain order to glue and use #4 weldon. This is a big undertaking and for the material, that price is right-just materal your labor is free.
Take your time, get help, use jigs to help hold it straight while the glue dries. You don't need clamps. Yes no clamps. When you apply the "solvent (#4) it will melt the acrylic- both sides and just the weight of the piece, and of course jigs to keep it straight, will settle into the glue area.

HTH

wanareef · 01-03-2003, 06:45 PM

Mike

Nice tank. Like to see more of that coast to coast. What size are the "comb theeth"? How much clearance is back there. Saw your plans on the other board. Very impressive.

Plese take lots of pictures.