Acrylic fabrication questions? I can help!

Might I ask: did it have a brand-name on the label, or a type? (cell cast, coninuous cast, extruded, etc)

Also, what are you using it for? i.e. what are you building?
 
Might I ask: did it have a brand-name on the label, or a type? (cell cast, coninuous cast, extruded, etc)

Also, what are you using it for? i.e. what are you building?

Thank you for helping Floyd. :) I build odds and ends for my aquarium such as algae clips. the label just says acrylic...
 
I am planning on building a frag tank in the near future. The dimensions are 70in x 12in x 18in(wide). Is 3/8in acrylic good for those dimensions. I will have a eurobraced top as well.
 
Are you going to do any cross braces? At 12" deep, 3/8" is plenty but you still need some braces. Two 4" cross braces would do wonders for long term stability, along with 3" eurobracing.
 
Three cross braces with euro would be fine. I'd be worried about the sides bowing too much if you only did cross braces.
 
I'm look to put together a large acrylic aquarium. The dimensions would be 96"L x 32"W x 23.5"H. I'm not new to aquariums but I am new to building one. I'm a fairly handy guy with a really nice shop downstairs which includes an 8.5' x 3' shop table for assembly. I have read most of this article including the original and this is my plan.

3/4(.708)" Polycast cell cast acrylic 72" x 96"
3/4(.708)" Polycast cell cast acrylic 48" x 96"

Bottom - 96" x 32"
Front/Back - 96"x23.5"
Sides - 30.584" x 23.5"
Front top brace - 4" x 96"
Back top brace - 2" x 96"
Side/cross top braces (6) - 5" x 26"
All in 3/4"
I will also use the leftover 3/4" x 96" x 5" pieces (2) to build a Calfo overflow system that should also act as a brace for the back.
I would use the remaining scrap to test weld as much as possible.

Should this amount of bracing, including the Calfo Overflow, be enough?

Also, I plan to use the pin method with .0125" guitar string or 26 gauge pins and Weldon 4. Each piece will be prepped with a router and laminate bit. Attach sides to front. Attach back to sides. Attach top braces. Attach bottom.

As added comfort I was thinking of using the tilt and pour method with Weldon 40 to put a 3/8" "bead" in each corner to add additional conservatism to the build.

What are the community's thoughts on my

1. Acrylic Size?
2. Bracing?
3. Methodology?
4. Extra tilt and pour?

Thanks in advance for this amazing article and your responses.
 
Polycast is imperial thickness, so 3/4" = 0.750". It's Plexiglas-G that is metric, or 3/4" = 0.708" so take that into account.

If your OD requirement is 96 x 32 x 23.5 then your ends are going to be 2 * thickness smaller, so if 0.750" thick, ends will be 30.5 x 22 pieces, f/b will be 96.25 x 22, top/bot 96.25 x 32.25.

The added 0.25 is for allowing the fillet to form and to allow for flush trimming. The ends are actual dimensions since they are bonded on all 4 sides. The 0.25 can be 3/8", 1/2", or more, as long as you have enough to work with to allow for the fillet.

Squaring of the ends is important. These 2 pieces really need to be square, but more importantly, they need to be the same. It's a bit tough with 3/4" thick to double-stick tape those together and run them through the router to make them identical, but at worst they should have one corner squared off then they can be separated as long as each pass is done to both pieces back-to-back with the same settings.

Then for the front/back, you will pass these through such that both are the same height, and the same height as that same dim on the ends. So your final pass would be all 4 pieces with the same fence setting on the router. Tricky when you have 96" long pieces I imagine, maybe James/Acrylics can give you advice on that, I haven't made a tank that large.

top/bottom can be rough cut, you're going to trim off all 4 edges anyways.

For pins, get a hold of some stainless steel wire that dentists use for braces. Tough stuff, can handle the weight of the panels.

For solvent, I would try to DIY some. WO #4 isn't really that great, MC with 5% glacial AA and you're good for sure.

Should not need WO40 beads. James has stated in this thread that he solvent welds up to 2" thick panels, and then there's the whole WO40 vs solvent weld strength debate (short version: correctly done solvent welds win)

Question: laminate bit?
 
Great advice, but I'd suggest that this is not the place to learn how to mix acrylic solvent. Buy a pint or two of #4, and use it.

A couple of rollers and some saw horses can really help with 96" panels. Get setup with an infeed and an outfeed table to the router, and use fingers to keep the panel against the fence.
 
If you are not very precise with your machining WO40 can be used as it will fill in some unevenness. (is that a word?) I use a gig to hold panels in place and right angle clamps to be sure its perfect 90 degree square. A little angle helps with flow into the joint. Fun stuff.
 
Great advice, but I'd suggest that this is not the place to learn how to mix acrylic solvent. Buy a pint or two of #4, and use it

There is no mixing. You can use straight Methylene Chloride, right out of the bottle.

Get a very small amount of Glacial Acetic Acid and mix in 5% of that on volume and that causes the solvent to flow better when applying it.

That's literally as complicated as it gets. That 5% is ballpark. As long as it's less than 10% you're good. Even if it's only 2%, that works. It's really easy.

Weld-on #4 is fine for sumps, frag tanks, small projects, etc. But if I were investing 1000s into a display tank I would spend $50-$150 on the quality ingredients. Call it an investment
 
Thank you so much for advice. I will definitely look into the MC.

As far as a laminate bit...I thought I read somewhere that a laminate bit is a straight bit with a bearing on the end but I may have made it up. I intend to use a straight bit with a bearing on the end to shave off excess bottom/top material post construction as well a straight bit to joint all the joints. Any suggestions on brands?

Also, what brands of Acrylic should I be looking for? Chemcast? Polycast? Plexi-Glass?

Thanks in advance.
 
You posted "Polycast" above, so I thought that's what you were going to use. You mentioned having read this thread (article?) but this thread is several splits long and there is a ton of info, it took me weeks to get through it all in detail....so I'm guessing you didn't read it all?

Polycast is $$$ but it is good stuff. Plexiglas-G is the alternative. There pretty much is no other choice anymore. Acrylite used to be an option but after they've had some changes, and some reputable builders have ended up with acrylic that won't weld, that one had been dropped off the list. Synergy Reef won't even make sumps out of it anymore.

The laminate bit is really not useful because that is a straight fluted small diameter bit. The spiral upcut flush cutter is for trimming, and with 3/4" thick material, you will want a 1/2" diameter one.

For edge prep, you want a double-fluted straight cutter with a good diameter to it.
 
Where is a good place to get acrylic online? Cut and polished if possible.
I do have a tables saw and 3 routers but hate cutting plexi for large projects.
 
You don't want polished edges for bonding, just FYI

TAP Plastics, ePlastics / Ridout Plastics, US Plastics, but most are $$ compared to buying a full sheet locally.
 
You don't want polished edges for bonding, just FYI

TAP Plastics, ePlastics / Ridout Plastics, US Plastics, but most are $$ compared to buying a full sheet locally.

I meant routed edges.

I realize locally could be cheaper but the only thing they have is Acrylite and I just read no good anymore. They sell sheets and do not cut.

Not many plastic places here, maybe a glass place might have some.

US plastics does not list a brand on theirs do they?. Looked last night and could not find anything.. I have used them before and they are great.

So is good acrylic now? I saw you said plexiglas-g.

Thanks
For the help..
 
Yup, Plexiglas-G is always good. The generic equivalent is arguably good for building anything for yourself, it's called PMACS (pronounced p-max) and most vendors have it listed as produced by the parent company of Plexiglas which is Arkema
 
Polycast is imperial thickness, so 3/4" = 0.750". It's Plexiglas-G that is metric, or 3/4" = 0.708" so take that into account.
Just a note on this; Polycast/Polyone has started making their material in both metric and imperial thicknesses up to 1". They call it "to be comparable" with the international market. I call it a price increase ;-)

Anything above 1" is, or should be - imperial thickness.
So, when ordering Polycast, be clear on metric or imperial thicknesses.

James
 
My plans comments please.
I wanted to build this all myself : stand, sump, frag tank and main tank.
I wanted the stand to house the tank and frag tank and tied to the same sump.

The frag tank is going to be 6 or 8 inches high and 20"x20: rimless maybe 24"x24" Is 1/2" overkill?

The sump in gong to be 33″ long x 15″ wide x 15″ high I was going to use the rest of the 1/2" from frag tank and make the inside panels 3/8 and hopefully rimless? overkill using 1/2"?

Now the tank I want 48"x30" x 20" I have used the calculators and one calculator say 1/2" says it is fine with framing and other says 3/8 is fine. I want to use either euro or just a brace down the middle. Problem is 3/4" is 487.00$ and would require 2 pieces. That is more than I wanted to spend. I do not feel 1/2" is enough and should be 3/4".. Anyway to do this and save a little money. Maybe use 1/2" bottom and framing and 3/4 for the sides? Still is allot of money. I could reduce size some?

Are there more charts or calculators for acrylic other than garfs and http://diyfishkeepers.com ?


My choices locally for Plexiglas-G is 62x96: 1/4 214.00, 48x96: 3/8=240.00, 1/2" 322.00 and 3/4" 488.00 sound reasonable. 10.50 per 1/2 hr to cut.
 
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