46x46x24 acrylic

[lapin]

For the gap I use the 90 degree clamps I got from Harbor Freight as seen in the picture to hold up the sides. If i could find bigger ones I would use them.(anyone??) I set the gap with a feeler gauge. I have some 1" wide strips of teflon sheet that's about 1mm thick. I double that over and place it between the 2 pieces. The weight of the piece usually will compress it down to about 1mm. I clamp the pieces and pull out the strips. If i find I can not maintain the gap in the center I use some chips as spacers. I make them from the weld-on #40. You can lay a bead on something it wont stick to and cut pieces out of that. You will see those chips in the final seam, but if you make them very small they will not be noticed.

[lapin]

Originally Posted by snake661047

I see that would be an ideal set up. Space really isnt going to be an issue. What size acrylic would you use for a 24" water line?

The 2 calculators I use tell me I need .671 to .677 thickness if i'm using Acrylite GP cast. Since it is not avail in that thickness I round it up to .704=3/4" thick.

[snake661047]

whats the difference between gp and other cast acrylics

[lapin]

Originally Posted by snake661047

whats the difference between gp and other cast acrylics

That's the manufacture's web site i got a calculator spread sheet from years ago.. I wont go into the differences between manufactures products. They change over the years. You can read about that on forums like this one. The product I like right now and have been using is Plexiglas G says Chemcast GP on the paper covering. Comes out of Mexico. Not much is made in US anymore.

[McPuff]

I would suggest getting some scrap 1/4" acrylic so you can make some practice welds. I've built a few small tanks and a couple other projects with acrylic. It's not easy to get a good seam. The most important part is edge prep. Once you have a really nice edge, you need to ensure that you can get enough cement into the joint as has been pointed out. I haven't worked on large pieces so I never bothered to use pins... BUT I can certainly see how it would have improved my joints!! I went with quick and easy method to get the job done. But for a display tank I'd use a different approach. Even with practice, you still are not likely to get a great seam so just understand that it is not easy to make it look perfect. I will say that it is a FUN process to build with acrylic so enjoy it!

[chriscobb]

The tank can be built using Mc Bond...No need for Weld On 40. No benefit really in using the 40 for the build. You can get perfectly good, strong, clear seams if your edge prep is done correctly. That is a big key and I would highly suggest the pin method.

[lapin]

This a seam done on 1" with routed surfaces, scuffed with 440 w/d sandpaper and welded with #40. The orange cloth is on the inside so you can see the seam. The goober on the left side is what flows out of the seam on the downhill side under the tape. This will be cleaned up with a flush trim router then sanded and polished. You don't want any gaps or bubbles in the seam as they will cause a weak spot. Very tiny bubbles here and there are ok and should not present an issue other than cosmetic.

[snake661047]

I just got a quote today thru my work for 5/8 $520 and 3/4 $556 for a 4x8 sheet. I will need 2 so either way im over $1100 unless you guys know of cheaper places. This quote was from Alro metal and plastics

[lapin]

Originally Posted by snake661047

I just got a quote today thru my work for 5/8 $520 and 3/4 $556 for a 4x8 sheet. I will need 2 so either way im over $1100 unless you guys know of cheaper places. This quote was from Alro metal and plastics

I only have this recent quote on thick stuff.

A 48" X 96" sheet of 1" clear cast acrylic is $645.

[snake661047]

Is there a way to identify between cast and extruded? I found some that is almost the right size for another tank i want to build and want to make sure its not extruded