Joining acrylic...

[MarkS]

OK, I have finished my plans for 120 gallon sump for my 224 gallon tank. It will be made out of 3/8" acrylic and will be joined with Weld On #3 and then I will go over the joints with #16.

I do not have acces to the tools to cut the acrylic so I am going to have to rely on my acrylic shop tp do the cutting. <crossing fingers>

What I need to know info about how to join the acrylic pieces. I am going to make a jig out of plywood to keep the pieces at 90°. I remember reading somewhere that you are supposed to put a piece of felt between the wood and the acrylic. Is this to keep the acrylic from being scratched or does it have something to do with the glueing? Also, do I need to clamp the acrylic to the jig?

More questions will be coming...

Mark

P.S. Attached is the rendering of the sump.

P.P.S myreef, do your skimmers *have* to be in the sump or can I plumb it from the outside? It sure would take up a lot of room that I want ot use for a refugium.

[myreef]

Mark, I haven't ever heard of using felt to put between a jig and the acrylic, but I would assume it is for scratches and nothing else. I have used jigs and no felt and have not ever scratched any (that I know of). Are you getting the ends of the acrylic sheet joined on a jointer? If you do, this will make the #3 glue much easier and stronger to use. If not, the #3 will hold it in place while you put the bead of #16 on it. When you make your jig, can you make it so you can glue the inside edges? It will be hard to glue otherwise. Does that make sense?

No, my skimmers do not have to be in sump. You can plumb them outside the sump or run them in sump, your choice.

HTH good luck.

[MarkS]

Thanks, myreef!

The jig will be about 6' long and 2' high/wide in an 'L' shape. I am going to set it on a stand so that it rests at 45°. I should be able to glue from the inside.

Again, I am having the plastic shop cut the acrylic. I do not have access to a joiner and I do not think that the plastic shop uses one.

Mark

[myreef]

If the ends are not joined, then you will be able to tack it with Weldon #3, then you will have to go back with #16 to fill any gaps you may have.

I had to cut the end off a sump yesterday because it was too large to fir into my prop tank stand. I cut the end as best I could using a table saw, then glued the new piece on using #3 and then a bead of #16 all the way around. Water tested it and had zero leaks.....so you should be doing the same roughly. Just take the tube of #16 and use it like silicone. Good luck

[MarkS]

Originally posted by myreef
If the ends are not joined, then you will be able to tack it with Weldon #3, then you will have to go back with #16 to fill any gaps you may have.

.....Just take the tube of #16 and use it like silicone.

This is exactly what I was going to do.

Thanks,
Mark