Differnece between Plexiglass and acrylic?

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Modest_Man

Polypterus
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Jul 5, 2006
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Here's the deal, been browsing Craigslist for some scrap acrylic to try my hand at making an acrylic tank. Just for kicks. I figure start small and then work large.

I just found "plexiglass panels" that are 114" X 29" by (3/8") thick for $25 here.

Is it worth it to try out my routering and welding on plexi vs. acrylic? Any real differences? From the little I read searching plexi has less flex, so it would require a more precise cut and fit, and can shatter more easily. Others say they're the same and it's just a different name for the same thing.

Any plastic people around? If it would work, any thoughts on a good tank dimension to start with?
 
Ok, just did a bunch more reading. Looks like this will work wonderfully for my first adventure in tank making.

Is there any way to tell extruded from cast acrylic?

It looks like 3/8th inch is good for tanks up to 18". I will probably end up buying 5 sheets ($125) (I haven't drawn plans up but I could probably use 4 sheets, using a router to cut the top brace and using the acrylic from the two access holes for the small end sides) and will cut pieces for a 96" long X 29" wide X 18" high tank (217 gallons with a floor surface area of 2784 square inches).

Go big or go home right? I'll start out with the scrap and throw together a small tank to test out the cement (Weld On 16 or Weld on 4?).

The cement looks to be fairly cheap as well, though I'm not sure how much I'd need. Two pints of Weld On 16 would be $26. So all told I'd be looking at $150 (or $125) for a very nice 220 acrylic tank. If I can get it to work.

Anyone want to stop me before I go purchase some sheets?
 
Judgin by this....3/8's is likely cast ;)



A.: Extruded Acrylic Sheet is a more economical general purpose grade of acrylic sheet that is made utilizing an extrusion/die method to produce the sheet. This extrusion process is the most economical approach to the production of acrylic sheet. Extruded sheet however has limitations in its ability to be machined and fabricated, may have detectable "grains" in the surface of the sheet, will have lower physical properties then cast acrylic sheet and more so, it's overall optical quality is not within the standards of "cast acrylic" sheet. Also, extruded acrylic sheet is typically limited to a maximum thickness of 1/4" -so, when thicker sheet is desired, cast acrylic sheet is the only option.

Here is the link.

http://www.modernplastics.com/polycast-cellcast-acrylic-sheet-papermask-p-1003.html

The one just built in my buddies house is 6x4x18 I believe... And is 3/8's... ;) I believe totalled after materials and supplies.. 185.00. It bows pretty good... But is sound.

Here is another link I read in the past :)

http://www.professionalplastics.com/professionalplastics/content/BuildingAnAquarium2.doc

My buddy Richard Builds Acrylic tanks as a hobby... :) He doesn't really come here though...
 
I Usually go with Weldon 3 or 16. Weldon 16 being more Bulky... Like silicone.. vs. Watery...

If you can fabricate and smooth the edges right.. then the lower weldons are good ;) If not.. the better route is the higher weldons in my limited opinon ;)
 
Personally I would not stop you :) DIY is a HUGE part of the reason I am still in the hobby :D Go for it :) Make sure you test fill for a good period :) I filled my 250 for over 3 weeks (outside).
 
I with the masses here. Give it a shot, take a lot of pics and keep us updated on how it goes.
 
Thanks for the link Tongue, I've read that one before and it's a good read. Lots of specific information.

I'll draw up some plans after work today, and see if the acrylic is still available.

I just realized I spelled difference wrong in the title. :( What I get for doing it at 1am last night.
 
Acrylic and Plexiglas(this is the right spelling, only one 's') are the same thing, Plexiglas is just a brand name of acrylic and acrylic is the type of plastic
another important thing is that Lexan is also a brand name but it is not Acrylic, it is Polycarbonate(the stuff bulletproof windows are made of) it has more shock resistance than acrylic but is also more expensive
btw the price on that acrylic is cheaper then I have ever seen, "new" price for a piece like that would be around 300-400$
 
All right, so I'm picking up some of the Sunday. They were used as a walkway cover, and from what I can find out about acrylic walkway covers is that they're made of double-skinned acrylic sheets, which is pretty much Lexan. Good stuff?
 
Read up a bit and seems like double-skinned acrylic sheets are not good for tank making...dang. Bad bonding properties and too much flex.

Anyone know of a way to check what material these actually are when I go to check them out?
 
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