Acrylic fabrication questions? I can help!

[Nizz]

I am also thinking of doing a bigger tank. 72x30x30. According to the builder. I would need a 1/2". Again no rimless. There will be attached top with cut outs and a center brace.

 

[dahenley]

I am also thinking of doing a bigger tank. 72x30x30. According to the builder. I would need a 1/2". Again no rimless. There will be attached top with cut outs and a center brace.

im no pro, but you will need more then 1 center brace, or the center brace will be wide.

also, a friend of mine had a tank that was a 24x24 not 30x30, and his was made of 1/2 acrylic. it started crazing in the corners from the stress (it was professionally built, not a garage build)
also, it looked like it was going to explode due to the extreme bowing from top to bottom.

if you can upgrade the thickness, you will thank yourself later!!
also, if you havent built a bunch of tanks or super confident (and the home insurance is paid up) then your not giving yourself any lee way for oppses or imperfect seams.

 

[peppie]

I am also thinking of doing a bigger tank. 72x30x30. According to the builder. I would need a 1/2". Again no rimless. There will be attached top with cut outs and a center brace.

30'' tall.... Min 3/4'' material

 

[Nizz]

That is what I was thinking. But I wanted to get the opinion of the people who have done this more then me. I feel good about doing this. I want to try some smaller tanks before I work on the bigger one I have in mine. This should be fun!

 

[Nizz]

Will 3/4" still bow a little also?

 

[Nizz]

also the way I am thinking about making the 40 breeder and 280 gal tank. The 40 breeder I would like to do a 3/4" top around the edge of the side panels for my bracing. The 72"x30"x30", I was thinking of doing two holes in the top. The center bracing being about 6-8" wide and sides of the top being 3" wide. (all of this as you are looking from the top of the tank.)

 

[Acrylics]

As I do agree that this thread is full of info. Just seeing if everybody uses the Garf site to get there tank builds info and general size of the acrylic since they provide it.

but their info is garbage.. dunno why they can't learn any better?

also the way I am thinking about making the 40 breeder and 280 gal tank. The 40 breeder I would like to do a 3/4" top around the edge of the side panels for my bracing.

not gonna hurt, but what purpose would this serve?

The 72"x30"x30", I was thinking of doing two holes in the top. The center bracing being about 6-8" wide and sides of the top being 3" wide. (all of this as you are looking from the top of the tank.)

Will 3/4" still bow a little also?

yes it will bow a little, bit not badly. Your bracing scheme won't help in this though; if just doing a single cross-brace, should make the flange (euro-brace) wider - something more like 4-4.5".

James

 

[Nizz]

I mainly wanted the 40 breeder to be a QT. I might set another one up for a nano reef later. If I set another one up for a reef. Would it be safer for a 1 - 1.5" euro-bracing?

What would help with the bracing to help minimize the bowing? Other then increase in thickness.

 

[sick_bubblegum]

i have some questions about edge finishing, before assembly.

is there a recommended scraper i could get at home depot?
after the edges are scraped, how should i polish the edges? i have read that flame polishing can lead to future issues.

thanks.

 

[peppie]

i have some questions about edge finishing, before assembly.

is there a recommended scraper i could get at home depot?
after the edges are scraped, how should i polish the edges? i have read that flame polishing can lead to future issues.

thanks.

IMO it is not good practice to use a scrapper for the final prep to and edge. You should take the router to the edge for final prep.
If you must use a scraper, I have had great results using a cabinet scraper, or card scraper. You MUST keep the scraper 90 deg to the face, this takes practice. There may be other scrapers that will work, but this type has worked well for me.
As for flame polishing... Cant say I would take a chance..

 

[Acrylics]

I mainly wanted the 40 breeder to be a QT. I might set another one up for a nano reef later. If I set another one up for a reef. Would it be safer for a 1 - 1.5" euro-bracing?

I will pretty much never recommend anything less than 2"

What would help with the bracing to help minimize the bowing? Other then increase in thickness.

make it wider is the pretty much the only thing that has any effect. It won't help the bowing in the middle of the panel very much, you simply need thicker material for this, but will help immensely at the top and also strain on the joints.

BTW using a thicker top doesn't do much of anything. You could use a 1/2" acrylic top or a 6" top - the bowing will be the same. It's a gimmick used by mass production tank mfrs to make extra money. Use $3 more in material and get an extra $25 to do it. Same glue joints, same machining on the same CNC. Won't change bowing or load bearing capabilities much/if any.. They're not out anything extra but $3 in material and you're out $25 with little/no benefit.
Yes, this crap irritates me so I call 'em on it

James

 

[Acrylics]

i have some questions about edge finishing, before assembly.

is there a recommended scraper i could get at home depot?

as previously mentioned, the pieces should be routed smooth and consistent and that's the only edge prep that you should need. Scraping edges is laborious and of only marginal benefit.

after the edges are scraped, how should i polish the edges? i have read that flame polishing can lead to future issues.

you don't. Simply routed and then glued. Any polishing; flame or buffing or whatever is done after everything is complete.

Anyone who says to flame polish prior to gluing is either A) an idiot or B) trying to mess you up. It can/will lead to instant crazing the second any solvent cement is applied.

James

 

[sick_bubblegum]

as previously mentioned, the pieces should be routed smooth and consistent and that's the only edge prep that you should need. Scraping edges is laborious and of only marginal benefit.
you don't. Simply routed and then glued. Any polishing; flame or buffing or whatever is done after everything is complete.

how would i route the edges once i receive the pieces from the shop? they will be doing all the cutting for me. how would i route without taking too much off? and keep it straight?

Anyone who says to flame polish prior to gluing is either A) an idiot or B) trying to mess you up. It can/will lead to instant crazing the second any solvent cement is applied.

James

but it's ok to flame polish the exposed edges AFTER it has been glued together?

 

[wbdevers]

+1 on the AFTER welding. Acrylics is dead on about it crazing.

 

[Nizz]

can someone pm a good place to purchase online acrylic that they use?

 

[Nizz]

so I called a company to get a price quote for the dimensions of a 40 breeder at 3/8" thickness. For Polycast it came to $500 (est.) and Plexi G $250 (set.) with rough freight charge. Does that sounds about right.

 

[Acrylics]

so I called a company to get a price quote for the dimensions of a 40 breeder at 3/8" thickness. For Polycast it came to $500 (est.) and Plexi G $250 (set.) with rough freight charge. Does that sounds about right.

no. not at all.. what are the specific dimensions of the tank?

James

 

[Nizz]

The dimensions I was are 36" L x 18"W x 16"H with 3/8" thickness. I know I need to compensate for the thickness. This was just get a quote. They also were going to charge me a broken case fee for the polycast because I wont be buying a case. Which I don't like personally. But I didn't know what the price difference was of the two types of acrylic.

 

[Acrylics]

The dimensions I was are 36" L x 18"W x 16"H with 3/8" thickness. I know I need to compensate for the thickness. This was just get a quote. They also were going to charge me a broken case fee for the polycast because I wont be buying a case. Which I don't like personally. But I didn't know what the price difference was of the two types of acrylic.

Broken case fee..lmao, what a crock.. the fact is they don't keep it around and will have to order a sheet and they simply don't want to so they give you a price high enough to convince you to use the Plex G.. which is fine, but I still call BS.

Your price for the plex g is ok; roughly $10/ft plus shipping. The Polycast should run about $50 more but refer to the above

On this size tank, I'd usually recommend someone go buy a glass tank for less than 1/2 the cost, unless the glass simply won't fit your needs?

James

 

[Nizz]

Yea I would buy a glass tank because of the size. But I am more or less using this time when putting that tank together as practice for when I get the chance to make the bigger tank.