Acrylic tank bulkhead patching

[bobble28]

Hi guys! Need some advice or pointed in the right direction if there's a thread here on r2r for it. I picked up a 140g acrylic sump for dirt cheap last weekend only problem is it has 3 holes drilled in it with bulkheads, 2 for external pump and skimmer not sure what the 3rd was used for. I'm planning to patch them with some 3/8" acrylic and weld on #4 I have laying around. Anything special about this process or just clean it up, make sure the patch is bigger than the holes and weld away? I've done a couple little projects with acrylic in the past just not sure about the best way to do this so it doesn't leak. I'd prefer not to use bulkheads and caps (I'm afraid that route they'll get kicked, tripped over, leak etc...) and cause more damage than anything. Tia for any help!

 

[hijinks7]

I'd also use weldon 16 like a bead of silicone around the outside edges of your patch to be sure they are water tight.

 

[cromag27]

how old is the sci grip? has the can been opened? do not use 16.

 

[bobble28]

how old is the sci grip? has the can been opened? do not use 16.

The weld on 4 is brand new never been opened, I don't have any 16. I bought it a few months ago in anticipation of getting an acrylic tank and turning it into a sump but came across this and went this way instead.

 

[bobble28]

Bump, any advice or pointed in the right direction is much appreciated.

 

[Awesome Dennis]

I'd use the Weldon 4 and attach the patch over the holes on the inside.

 

[bobble28]

I'd use the Weldon 4 and attach the patch over the holes on the inside.

That's my plan. Does the patch need to be clamped or can I just hold it in place until the weld on sets enough to keep it there, also how far past the holes should I cover (thinking about an inch all the way around)? Thanks!

 

[Matthew Frost]

I would set the sump in that side first. Weld-on 4 will definitely work, let the capillary action pull it in and when you have the whole patch wet with weld-on just put a little weight on it (soup can etc.) Just discourages bubbles.

 

[bobble28]

I would set the sump in that side first. Weld-on 4 will definitely work, let the capillary action pull it in and when you have the whole patch wet with weld-on just put a little weight on it (soup can etc.) Just discourages bubbles.

Ok, I appreciate the advice! I'm hoping to get it patched this weekend. I'll let you guys know how it goes! Thanks again!

 

[bobble28]

One last question before I get started on this patch today lol the piece of acrylic I have is what I practiced my sanding and polishing with novus on. I cleaned it really good with vinegar. If there's any residule coating from the novus left is that going to cause any problems with getting a good weld?

 

[bobble28]

Got the patches cut! Going to clean up around the holes and do a practice run on some scrap. Hopefully everything goes alright I'll update later.

 

[bobble28]

One down, thinking I should try to get some weld-on in the air pocket just off center of the bottom of the hole. Any thoughts? About to start the big patch.

 

[ReeferBob]

That looks great it will never leak. Bubbles like that are normal.

 

[Matthew Frost]

No need to mess with trying to fill that bubble. The weld on will not go into that bubble because the air that's in there can't escape. That patch looks solid, don't mess with it now for at least 24 hours.

 

[bobble28]

Thanks guys, I let it sit until about 2min ago and flipped the tank to do the big patch. Im thinking the big patch didn't turn out as well as the small one. I'll post a pic in a little while when I set it back down and you guys can tell me what you think.

 

[bobble28]

Well here it is.

 

[Matthew Frost]

It looks like you have some solid areas of weld in that patch. Are you going to drill through those holes again and put bulk heads in them?

 

[bobble28]

It looks like you have some solid areas of weld in that patch. Are you going to drill through those holes again and put bulk heads in them?

No I'm not drilling them.

 

[Matthew Frost]

Here's what is do if you're worried about that patch. Turn the tank upside down, take a syringe with a needle on it and some weld on 4 and "inject" the bubble areas. I don't think you need to but if you're worried about it.

 

[bobble28]

Here's what is do if you're worried about that patch. Turn the tank upside down, take a syringe with a needle on it and some weld on 4 and "inject" the bubble areas. I don't think you need to but if you're worried about it.

I was thinking about doing that just at the holes to be safe. I can get weld on into the big air bubbles around the bulkhead holes. I tried the bottom of the holes already and they filled right in.