Acrylic, Seams
 

Ok, I messed up my last seam.. the bottom of my sump!! Argh.. I guess I took to long going around the tank with the solvent. I am using the "pins" method. When I pulled the pins the piece didn't fall down, (my first indication it went bad), so I pushed it down and of course some stuff squeezes out.. But I can tell my seam is crap cause it is not smooth, it has ridges like it did after I routered it. I assume the solvent dried before I could pull the pins.. Anyways.. can I save this???? It is only a 15 x 15 x 12 sump.. so not a lot of pressure.. could some weldon 40 or gussets along the bottom be ok? or do I need to redo my entire sump!!! :(

If you can get some more Weldon 3 or 4 in there and clamp it, you should be fine. Chances are if it doesn't leak when you test fill it, it won't leak later.

A hot air plastic welder is the perfect solution but not everyone has access to one.

I don't know how to get any in there.. I just looked up weldon 40.. I thought it was in a tube like #16 but it is more like a paste you have to smear on.. I had read it was like caulking, but I think that is weldon 42.. looks expensive as well.. I wanted to buy the acid that keeps the solvent from evaporating so fast but none of the plastic shops here will sell it too me.

I hope this isn't toast.. I have but a lot of time into this little bugger!! :D

why not use some 16??


i reinforce all my exterior joints with a bead of 16, it isn't pretty but thats not what matters.

yeah, I have been thinking about that.. I was going to trim off the excess from the base.. but now maybe I will leave it on and put a bead around the outside.

I do notice that when I use weldon 16 or or even #4 that it leaves tiny bubbles in it. What causes that.. even on all my seams there are tiny bubbles along the very edge (out side of the seam).

Chad just cut a piece of acrylic about 1" wide and glue that to the inside bottom of your sump. Put it in place and squirt weldon 5 everywhere around the joints until it seeped through then press it down with something. That should seal the gap and better than starting over. besides its just the bottom of the sump right? probably covered with sand of some sort...... or gunk....

yeah, I might just do something like that. If I had left it alone to what it was originally I would have had a perfect joint I think.. but noooo.. I had to try and make it perfect.. and well.. that is when things went wrong! lol..

oh well... my learning experience for sure.

Hey Gents, I just bought an acrylic sump that turned out to have been dropped on one of the corners and is leaking very slowly from a 1/2 inch crack just above the bottom seam and about 1 inch from the corner, stupidly I tried regular aquarium silicone to stop it but it didn't work out.
Where can I snag some of this weldon stuff?
I had heard I needed to go to a specialty retailer to get something suitable for my problem?
thanks a bunch guys.....

You can get your supplies at Industrial Paints and plastics. You will probably want to buy some acrylic and cut it out so it covers the crack.. I was told an inch in each direction of the crack.. then use the weldon #4 to wick it in.. or weldon #16 if you have gaps.

Can someone explain, if it is possible, how to use Weldon #16 and not get tiny bubbles in it? I am using it like caulking around my base. When I applied it, no bubbles.. as it sets I am seeing tiny bubbles..

Is that just normal? No way to get rid of it?