Acrylic fabrication questions? I can help!

[neurosis05]

building a sump size will be
30" x 20" x 16"
baffles will be located near the middle and 2 will be 16" high, the last will be 14.5" high

Can I get away with using 1/4"? I found a guy who sells plexi-glass G brand
Thanks

 

[Acrylics]

yup, you can get away with 1/4".. preferably with a perimeter flange?

James

 

[neurosis05]

yup, you can get away with 1/4".. preferably with a perimeter flange?

James

If I put in a perimeter flange I will be real close to running out of material. I'm messing around with different dimensions of the sump, but if I absolutely have to, can I use a different 1/4" acrylic sheet brand material for the baffles or the perimeter piece? I have some lying around from my failed sump.

 

[Acrylics]

If I put in a perimeter flange I will be real close to running out of material. I'm messing around with different dimensions of the sump, but if I absolutely have to, can I use a different 1/4" acrylic sheet brand material for the baffles or the perimeter piece? I have some lying around from my failed sump.

yes, you can use different brands. We'd want to use the best material possible for the structural application and then the "not as good" stuff for inner compartments and the like. Even if you have to use scrap extruded for the baffles - it's fine and it'll glue just fine. Structure is the most critical, everything else is secondary..

James

 

[Steveb]

Hi James I have a quick question. In an earlier post I asked about enlarging and/or adding holes to my tank. The time is getting close to do that so I wanted to find out what is the best method for protecting the front panel of the tank (I have already removed the masking) since I am going to have to flip it over to get to the bottom. I thought about blankets etc. but just wanted to get an expert opinion.

Thanks.

 

[neurosis05]

yes, you can use different brands. We'd want to use the best material possible for the structural application and then the "not as good" stuff for inner compartments and the like. Even if you have to use scrap extruded for the baffles - it's fine and it'll glue just fine. Structure is the most critical, everything else is secondary..

James

I redesigned it so I can get it all out of one sheet. It will be close though. Now I just hope I can glue it right this time:headwallblue: Just need to take my time. Thanks again James

-Jason

 

[marlinmero]

to much of a bow?

to much of a bow?

I finally set up my new "used" acrylic tank out in my garage to do a leak test for a week. I'm new to acrylic so im not sure how much of a bow is normal. i wasnt sure how to measure it but i took my t-square and got about a half inch bow side to side. then did the same from the top down. looked like half inch on the top part of the face and like an inch at the bottom. so does a half inch bow sound ok?
OH and its a 180. 72"x24"x24" i believe. im not sure the height part

 

[djjester611]

Following

 

[neurosis05]

Ok so I had a local shop cut my 1/4" sheet of plexiglass brand G and they used up the entire sheet for my sump tank. Unfortunately they forgot my bottom sheet. They special ordered the plexiglass and if they order more it will be a week before it arrives. Can I use a lesser material for the bottom? :sad2:

 

[Floyd R Turbo]

How did they "forget" it? Did you give them a layout, or just the dims of the pieces you needed?

I have found that with acrylics shops, no matter how 'experienced' they are - you pretty much have to tell them precisely what you want. If they would have been able to cut everything from one sheet (cut lines have to be arranged just right, and done in the right order) but they erred and did it wrong, I'd ask them to cut your piece and eat the cost. If there was no way they could have nested the pieces such that it was able to be cut out of one sheet, then that's just the way it is.

1/4" is the thinnest I would go, no matter what though.

How big is this sump that you're doing the whole thing out of 1/4"?

 

[peppie]

Ok so I had a local shop cut my 1/4" sheet of plexiglass brand G and they used up the entire sheet for my sump tank. Unfortunately they forgot my bottom sheet. They special ordered the plexiglass and if they order more it will be a week before it arrives. Can I use a lesser material for the bottom? :sad2:

Nope, the bottom is a structural part of the vessel, all of the sides are welded to it.

 

[neurosis05]

How did they "forget" it? Did you give them a layout, or just the dims of the pieces you needed?

I have found that with acrylics shops, no matter how 'experienced' they are - you pretty much have to tell them precisely what you want. If they would have been able to cut everything from one sheet (cut lines have to be arranged just right, and done in the right order) but they erred and did it wrong, I'd ask them to cut your piece and eat the cost. If there was no way they could have nested the pieces such that it was able to be cut out of one sheet, then that's just the way it is.

1/4" is the thinnest I would go, no matter what though.

How big is this sump that you're doing the whole thing out of 1/4"?

Sump is 48" long x 15" wide x 18" tall. I did send them a cut sheet, and multiple emails. I Asked them if they could make me a perimeter flange and had to explain it in great detail, even drew em a pic. I think they were so concerned with it they ignored everything else. As I left the shop I stopped and decided I should make sure they had all pieces. I noticed they had missed one baffle, so I went back in and had them cut it from one of the scrap drops they included. I must have confused the bottom piece with another scrap drop piece that is about 3" too short.

Nope, the bottom is a structural part of the vessel, all of the sides are welded to it.

weak sauce

 

[Acrylics]

Ok so I had a local shop cut my 1/4" sheet of plexiglass brand G and they used up the entire sheet for my sump tank. Unfortunately they forgot my bottom sheet. They special ordered the plexiglass and if they order more it will be a week before it arrives. Can I use a lesser material for the bottom? :sad2:

While the Plex G would be preferred, it wouldn't bother me at all, not that big of a sump.. Do not use another cast material though. If they had to special order this, it means they don't have anything good.. Use an extruded material for the bottom, Acrylite FF if they have it, it's the best of them IMO. But any of the rest will do.

If you use extruded for the bottom, pay careful attention - that joint will set quickly so be forewarned..

James

 

[neurosis05]

While the Plex G would be preferred, it wouldn't bother me at all, not that big of a sump.. Do not use another cast material though. If they had to special order this, it means they don't have anything good.. Use an extruded material for the bottom, Acrylite FF if they have it, it's the best of them IMO. But any of the rest will do.

If you use extruded for the bottom, pay careful attention - that joint will set quickly so be forewarned..

James

Oh I changed the dimension of the sump. It is now 48" long x 15" wide x 18" tall. Hope that doesn't make a huge difference.

 

[Acrylics]

Oh I changed the dimension of the sump. It is now 48" long x 15" wide x 18" tall. Hope that doesn't make a huge difference.

no, I caught that, I assume the standard baffles and such?

 

[peppie]

sump is 48" long x 15" wide x 18" tall. I did send them a cut sheet, and multiple emails. I asked them if they could make me a perimeter flange and had to explain it in great detail, even drew em a pic. I think they were so concerned with it they ignored everything else. As i left the shop i stopped and decided i should make sure they had all pieces. I noticed they had missed one baffle, so i went back in and had them cut it from one of the scrap drops they included. I must have confused the bottom piece with another scrap drop piece that is about 3" too short.

Weak sauce

weak sauce?????

 

[sandtrout]

Anyone have experience working with a cell cast product called PMACS acrylic sheet made by Altuglas, same company that makes Plexiglass?

I have an opportunity to piggy back on a large order (100+ sheets) of 5' x 8', 1" thick material and save alot of money.

Despite the money savings, I don't want to go down this road unless the acrylic is up to the task of becoming a display tank.

In comparing PMACS to Plex G the plastic supplier responded "It's a lower cost alternative to plex g and it's cast from the same resin pellets." Reading the tech specs I see no difference from PMACS and Plex G. Also, I've been told PMACS is manufactured domestically.

any thoughts? thanks in advance,

Scott

 

[neurosis05]

no, I caught that, I assume the standard baffles and such?

yeah. 3 baffles. 2" Perimeter flange

weak sauce?????

sorry. Its slang it means "lame" or "that sucks"

 

[Floyd R Turbo]

Anyone have experience working with a cell cast product called PMACS acrylic sheet made by Altuglas, same company that makes Plexiglass?

I have an opportunity to piggy back on a large order (100+ sheets) of 5' x 8', 1" thick material and save alot of money.

Despite the money savings, I don't want to go down this road unless the acrylic is up to the task of becoming a display tank.

In comparing PMACS to Plex G the plastic supplier responded "It's a lower cost alternative to plex g and it's cast from the same resin pellets." Reading the tech specs I see no difference from PMACS and Plex G. Also, I've been told PMACS is manufactured domestically.

any thoughts? thanks in advance,

Scott

See below from a post a few months back (#2709 to be exact)

I would look into finding the "general purpose" 3/8" cast acrylic, it is exactly the same as Plexiglas-G except it has no print on the mask and is 20% or so less. Still made by Arkema and it's what I have been using (also have used 1/2" as well as 1/2" and 3/8" black, same thing). You have to sometimes train your acrylic supplier to look for the right thing though

After a bunch of research and a few headaches, found out I was given bad info on this one

The Arkema material with no branding on it at all is called "P-Max" and made and sold in truckloads only. This material is made to compete with the cheap imports and it comes with *absolutely no* warranties, certifications, tolerances, or quality controls. If you have issues with the material - the answer from Arkema is "too bad" ..essentially; you paid your money, you take your chances..

FWIW, most plastic salesmen know squat about it and even the CS at Arkema didn't know there was a difference. I had to talk to the chief technical engineer and regional sales rep to actually get the truth on this material.

That said, for sumps and whatnot, it's fine, but I after learning what I have - I would *never* recommend it for display aquaria..

James

There are zero quality controls and zero warranty on this product. I use it all the time for sumps, frag tanks, etc, but for display tanks I would use Plex-G. For a personal tank, you probably would be OK. But if there is an imperfection in the material (speck of black, inclusion, etc) it's all on you. Just so you know. But it's not like the situation would be any different if you used Plex-G, because unless you buy $100K of material from them in a year, they're not going to pay for re-building your tank because that warranty is void as soon as you machine the material.

P-max is made in the same plant in Mexico (not domestic) that Plex-G is, but not made to the same high specifications. In fact, I don't think they even check to make sure it's the right thickness, they just make it as cheap as possible so that it can compete with the import products.

I like the stuff because it's easily 25% less expensive, but I haven't checked -G prices lately. I know that 1/4" came way down recently via one of my suppliers and that price spike 6 months ago is now gone. So like I said, prob fine for a personal tank.

 

[sandtrout]

Thanks so much for the reply Floyd

Ohhhh, so PMACS is pronounced "p-max", got it, I have read about this before, this is the mex-plex then?

Regarding the price, not sure what G goes for ($25?), I would be paying $11.80 sq. ft. for 1" PMACS, tough to turn that down.

Reading between the lines on your post, PMACS has seamed up good and strong for you but you can't count on consistency between batches or sheets, and thus can't recommend it?

My plan is for a personal display tank, 84"x30"x30", using 3 - 5'x8' 1" sheets.

I know edge prep is critical to good seams. I have access to a cnc router and plan to go that route using a brand new bit, water jet is also an option. These would be huge time savers and very accurate. Any possible problems with these approaches?