Weld-on 40 to fill gaps

[Graphic]

Will weld 40 work with

no, #40 will not adhere to marine star board or any oil based plastic. any petro based plastics need to be heat welded together i.e. polyethylene, polypropylene, abs… u cannot heat weld petro plastic to acrylic in any way either. Its like oil and water… they just dont mix…. Something just isnt adding up here lol… to me, that box did not come on that tank… i can see patches and different types and pieces of materials. If it were simply cut off and put back on it would no look like this. Whats it look like on the inside of the tank?

So the overflow I think was added at some point (not by previous owner I believe) and had no issues and still doesn’t. Then the outside of overflow was cut make it fit through the door way. They removed 3” from the overflow then siliconed and used that epoxy to glue the outside of the overflow back on.

To fix it, I would need to rebond the overflow to itself, the back piece, not the overflow to the tank.

The inside of what might be starboard is smooth. How can I tell what it is aside from texture? I could do a quick video call if that’s okay?

 

[wednesday13]

Will weld 40 work with




So the overflow I think was added at some point (not by previous owner I believe) and had no issues and still doesn’t. Then the outside of overflow was cut make it fit through the door way. They removed 3” from the overflow then siliconed and used that epoxy to glue the outside of the overflow back on.

To fix it, I would need to rebond the overflow to itself, the back piece, not the overflow to the tank.

The inside of what might be starboard is smooth. How can I tell what it is aside from texture? I could do a quick video call if that’s okay?

If they used silicone on acrylic u have to take all that apart. Silicone will only adhere to acrylic minimally when used as a gasket on a tank window. It has no strength at all for butt joints like that on acrylic. U should honestly be able to pull it apart by hand if its siliconed together. Do u have weir teeth across the entire length of the tank or just holes entering the overflow box?
The only “proper” way to repair this would b to take every piece apart on the overflow that was siliconed, sand it down to the acrylic, re join the acrylic with weld on 40 or solvent #4. Id also ditch any of the textured material also.
Again id remove the box entirely and go with just the bulkhead holes unless u have weir teeth for the overflow in the back wall. Even then id just glue a piece of acrylic over the weir. That scenario would b much less work and cheaper than to mess with that frankensteined box.
my guess is they tried to modify it for better flow or something. Failed on every account lol… then sold it… it might have held water for a week or so using silicone, leaked… they added the cheap epoxy… held for another short period of time then it leaked again. Been there done that in my earlier years… how i know it doesnt end well with water pressure, time and not using the proper materials.
A dremel with rotozip bit will make fairly quick work of that box ?… as will a grinder and cut off disc (wear glasses) Can sand er smoot/clean again afterwards with an orbital or palm. If ur patient u can get very close to “cutting seams” flush with just a hacksaw blade by hand but it takes a while. Highly suggest u save ur self the same nightmare the previous owner had of a box failure after its up and running and just cut it off to move forward ?