Acrylic fabrication questions? I can help!

[Floyd R Turbo]

Possible, yes, but it presents problems. I can't quite see all of your design but you can't do a butt-end bond and expect long term strength, the bond will eventually get torn apart. You would want to laminate another piece on top of that joint.

Any sharp corner or gap in the joint is going to create a focused pressure point. One piece euros with radius cut inner corners have significantly less of this stress. So if you're building for a long-term use display tank, I would definitely go with a one piece euro.

If you're throwing together a frag tank and you really don't care how ugly it is, then you could do a piece together euro. If there is a failure of some sorts, it is less likely to be catastrophic and more likely to just happen gradually. At least that's my opinion

 

[overflowin]

It's a frag tank, I would like to get long term use out of it, but looks aren't really a priority. The thickness calculator says my dimensions are OK with no brace at all... just wondered if doing a piece together euro brace would be better than just a couple cross braces across the top...

Frag tank dimensions will be 82 x 30 x 17 made with 3/4 acrylite gp - Edit...

 

[Floyd R Turbo]

I don't put a lot of faith in calculation programs. I would refer to the man, James, on this one. IIRC he told me that the calculators are all based on a box with no holes (6 sides) and something like they come out as overbuilt or underbuilt if you go by their recommendations for a braced tank vs not, but I can't recall which. I seem to remember that if you go by their calc for a rimless tank, their recommendation is too thin. In this case your tank should probably be 1" thick, that's what my gut tells me.

If $$ is an issue, then you can actually build that tank out of 1/2" walls all around with a standard euro. Heck you might even be able to build it with 3/8" all around.

 

[overflowin]

i already have the 3/4... i'm trying to plan around what i have... Money is definitely an issue, I'm laid off right now, so i have time to work on stuff i already have, but making any major purchases will be on hold till i catch a call... that being said, if i can't do it safely, i will just wait and buy some more material to make a euro brace.

 

[Acrylics]

Hello,

i will introduce my self first, I'm Michael from the netherlands.

i need some advice about large fresh water tanks, i've welded a stainless steel tank size: 3,00 x 1,50 x 1,30 L x H x D

i was planning to place a optiwhite glass in it, but considering the weight and clearance i'm gathering info to build it with acrylic.
So far i know in europe acrylic is a unknown product for aquarium in private tanks, so i need the advice from experts

A big company in the US advised me to use 25 mil pmma, but i think its to thin and it will bowl out.
The whole sheet will be sealed in a stainless steal angular profile of 10cm overlap.

lot of questions, i hope someone got some experiance and can advice me.

Hi Michael,
I would probably use 2" (~50mm) on the front though you may be able to get away with something slightly thinner.
1.5" (~38mm) for the sides...if

Keep in mind you're going to lose overlap with material thickness. If you have 4" overlap now, once you place 2" acrylic in there with silicone, looking at more like 1.75-2" overlap leftover on the sides. This may present some issues for you. If I read your post incorrectly - my apologies.

HTH,
James

 

[Copa]

ok, thai you acrylics for the info.

so 50 mil for the front is the absolute minimum?

about the sealing, a supplier in the netherlands told me to seal it with acrylic sealer with no acid, you say silicone.
Does the silicone bond enough of seal it for long time?

regards

 

[easttexas]

I asked this in the DIY forum, but think I might get better response in here:

OK, so I've been in the reef scene sense 93, I've built many sumps, wave boxes, and a couple smaller tanks in the past, but my current project is for a 72x22x22 (external) with single end overflow (like a peninsula build, but its not really going to be one. I know I could get a bigger tank out of the 2 sheets it will take, but I am fitting into a pre-existing space, so I'll find a good use for the scraps. anyways;

1) my question is will a 4" perimeter and single 6 or 8" center brace be adequate? or will I have to use 2 center braces. I was planning on building it with 1/2" plexi-G which I have easy access too.

2) also, I plan on using 2 @ 32" leds for this build, so 3 holes for MH isn't needed if it makes any difference.

3) is there any "rule of thumb" for popping holes in the perimeter brace for returns. I planed on 6 @ 3/4" returns plumbed thru the brace

4) I have it drawn for a 17" smooth slot overflow on one of the 22" sides, do you think I will need to leave a connection point in the center with the top panel (I'm running the top continuous over the overflow box) or will it be strong enough with just the bottom of the weir 5" or so down?

Thanx
long time lurker, new poster:
Mark

 

[Floyd R Turbo]

1 & 2) Standard is 3" perimeter and 6" cross every 24", so you would have 2, if you wanted to have just one, I would beef up the perimeter to 4.5" and do an 8" crossbrace. 2" radius on all the inner corners, and round everything off, even if that is only scraping each edge with a razor blade to put a 45 on it - removes sharp corners that focus stress. The access holes are not placed with MH lighting in mind, but rather placed according to structural integrity.

3) I'm not 100% sure on this one, but I think as long as you have 2" of material all around the hole, should be OK - holes have virtually zero impact on stress, it just passes around it (as long as it's router cut or sanded/polished smooth). Again put a 45 on both sides of the hole.

4) let me make sure I understand - you are going to cut a slot on the side panel, then have an external overflow box bonded to the outside, and the euro top will extend around the overflow box, correct? if that is the case, and the overflow box is 'beefy' enough, along with the euro connection, that might be OK. I would want to see a sketch of it as there are probably stress points that you would want to minimize, done wrong they could become focus points that might cause problems down the road. I would also probably defer to James on that one

If it were me though, I would do internal and external stand-alone overflow boxes. Once you cut and bond, it's that way for life. If you design a proper set of internal/external boxes, you can make changes in the future. Also, pass-through holes are much less impactful to stress points. Plus I'm a huge fan of the BeanAnimal 3-pipe system on an internal/external overflow system.

 

[easttexas]

ok, I quickly changed my drawing to reflect 3 openings, and hopefully the line drawing will post

in the drawing I have a center brace in the overflow, but would like to remove it if possible, if not, no biggie

 

[easttexas]

that came out kinda small, give me a minute to upload a zoom view

 

[easttexas]

ok, blew up the side view for you. Routing the holes instead of hole sawing them is no big deal for me, I used to be in the car stereo biz and have a full wood shop left from those days

as you can see, I already planned on doing a Bean Animal system thru the bottom

I'm shoehorning the tank into an arched opening next to my current tank so it will be see thru, but the end view is kinda blocked by a rather large column. I am inserting the tank partway into the opening like an inwall and the overflow has to go around the wall corner so to say.

 

[Floyd R Turbo]

Test

That was odd...I couldn't get to the next page even though it listed it...

 

[easttexas]

that was weird, for a bit, all my post with pictures were gone, but they came back now for me. take a look for me Floyd

 

[Floyd R Turbo]

Can't see any of them, only one I could see is the link that was in the one post you made, I got the link in the e-mail alert but the post disappeared. Banned link?

 

[easttexas]

I don't know, its a standard photo bucket link like I use in the other forums I'm on. I'm looking at it now 4 post above. maybe I don't have enough post to do pictures yet?

 

[easttexas]

ok, if I'm not logged in, I can't see the post at all, the whole post are gone with pictures in them. as soon as I log in, the post appear? that is one weird one. is their another way to get you the drawings?

 

[Floyd R Turbo]

Actually it was a shutterfly link and yes that is probably it, not sure what min post count is to post pics.

 

[Floyd R Turbo]

I still see nothing

 

[dahenley]

when your on photo bucket, you have to copy the "direct Link" found on the right hand side of the page (next to the picture)
also, if you marked your photo bucket as "private" then no one but you can see the pictures.

 

[Floyd R Turbo]

No you need to copy the IMG code link, and if the pic is private, no one can see if when looking at your photobucket page, but if you post a link to a private directory, the pic will show up.