Bulkhead to PVC... what am I doing wrong?

[samnaz]

After applying both glue and primer to pipe and bulkhead, I inserted pipe with a 1/4” turn and pressed joints together firmly for 30 seconds.

That wasn’t long enough, pipe started to creep out. So I held it together with all my strength for over 4 minutes. Assumed it would be long enough. Yet the pipe still forced its way out a few mm.

Is this normal? It certainly does not look like a water tight seal to me.

Should I be using ABS to PVC specific cement? This did not happen much when I joined pvc pipe to pvc fittings.

See photos...







I’m using this...

 

[wangspeed]

When gluing ABS to PVC, I skip using primer as it makes things too gooey and you get severe push out. I also use “universal” solvent, like Uniweld 6200.

 

[DipSpit]

^ What he/she said. When you put these fittings together you must hold them for a good 30ish seconds. The chemical reaction taking place inside the joint results in "push out." They are probably still watertight, but, if you feel badly about it, simply holding them together when you join them will fix the issue.

 

[ca1ore]

Because bulkheads are designed to have PVC inserted into them; not the bulkhead inserted into PVC. Appears to me you’re doing it wrong. Maybe it will hold; maybe it won’t

 

[BigJim]

Because bulkheads are designed to have PVC inserted into them; not the bulkhead inserted into PVC. You’re doing it wrong. Maybe it will hold; maybe it won’t

I agree with this. Google "bulkhead reef" and you will see many images of how it should look.

 

[ca1ore]

Looked at the pictures on a bigger screen. Maybe you didn’t do it wrong lol. I agree to skip the primer. As long as the welded joint is not moving you should be ok.

 

[samnaz]

^ What he/she said. When you put these fittings together you must hold them for a good 30ish seconds. The chemical reaction taking place inside the joint results in "push out." They are probably still watertight, but, if you feel badly about it, simply holding them together when you join them will fix the issue.

Like I said, I tried holding the fittings together for 30 seconds and it was not enough, so I tried another and held for well over 4 minutes and still they did not stay put.

Because bulkheads are designed to have PVC inserted into them; not the bulkhead inserted into PVC. Appears to me you’re doing it wrong. Maybe it will hold; maybe it won’t

I agree with this. Google "bulkhead reef" and you will see many images of how it should look.

I'm not doing it wrong. There is PVC pipe connecting the bulkhead to the union. It wouldn't even be possible to connect a bulkhead and union without pipe holding them together, as far as I know.

 

[hatfielj]

Did you chamfer the edges of the PVC pipe before applying primer/glue? Also, I usually twist the pipe around several full twists before holding it together. It helps distribute the cement. And I disagree with whoever said not to use primer. The primer really helps.
Otherwise, it should hold fine. As long as you applied a generous amount of cement, it will be water tight. If not, get new parts and start over.

 

[DipSpit]

Like I said, I tried holding the fittings together for 30 seconds and it was not enough, so I tried another and held for well over 4 minutes and still they did not stay put.





I'm not doing it wrong. There is PVC pipe connecting the bulkhead to the union. It wouldn't even be possible to connect a bulkhead and union without pipe holding them together, as far as I know.

Oops, didn't read that part. Something is off here I have never had this issue before, but don't think I have ever glued ABS to PVC - you may need a different solvent. Try clamping them together while drying? After the 4 minutes was the joint moveable of solidified?

That being said, I always use thread x thread bulkheads and recommend that.

 

[samnaz]

Did you chamfer the edges of the PVC pipe before applying primer/glue? Also, I usually twist the pipe around several full twists before holding it together. It helps distribute the cement. And I disagree with whoever said not to use primer. The primer really helps.
Otherwise, it should hold fine. As long as you applied a generous amount of cement, it will be water tight. If not, get new parts and start over.

I did chamfer the edges. Maybe I didn’t apply a generous amount of glue, or maybe I used too much? Either way I got some extra parts so I can redo it.

 

[hatfielj]

Are you sure you're not using an oversized european bulk head? When you dry fit the parts are they pretty snug? It should be really hard to press them together dry.

 

[samnaz]

Are you sure you're not using an oversized european bulk head? When you dry fit the parts are they pretty snug? It should be really hard to press them together dry.

Yes and yes. Was very hard to dry fit. I think I will try maybe a half turn or more after applying primer/cement. Maybe it’s not being distributed evenly enough... and maybe that’s why it took so long to set / dry?

 

[BigJim]

I'm not doing it wrong. There is PVC pipe connecting the bulkhead to the union. It wouldn't even be possible to connect a bulkhead and union without pipe holding them together, as far as I know.[/QUOTE]

I see that now on the second picture. Sorry about that.

 

[samnaz]

Oops, didn't read that part. Something is off here I have never had this issue before, but don't think I have ever glued ABS to PVC - you may need a different solvent. Try clamping them together while drying? After the 4 minutes was the joint moveable of solidified?

That being said, I always use thread x thread bulkheads and recommend that.

Clamping isn’t an option the bulkheads are installed on an overflow box, angle won’t allow for the size clamps I have.

I could just sit on it? Lol I was tempted to stand on it but thought that’s too much pressure. My hands were getting tired.

 

[joec]

"Should I be using ABS to PVC specific cement?"

Yes, its green

 

[DipSpit]

What about the Oatey 16 oz. Transition Cement joins ABS and PVC pipe. "The solvent cement is ideal for applications where the structure is plumbed in ABS and the local sewer system is plumbed in PVC."

 

[DipSpit]

"Should I be using ABS to PVC specific cement?"

Yes, its green

Jinx

 

[SmokeyGnar]

I used threaded bulkheads with food safe thread sealant to avoid the problem you’re having. Let us know if a different solvent works, that’s most likely the solution

 

[samnaz]

I’ve alwyas assumed slip fittings were the best choice in terms of leakage possibility. Cause the entire area of contact between fitting and pipe can easily be bonded... imagined bonding flat surfaces together just seems less risky and easily than binding two ridgid surfaces together.

I can see how threaded would be easier initially and more economical/reusable than slip, but my main concern is leakage.

 

[SmokeyGnar]

I’ve never had a leak in any threaded fitting carrying water. I take care to properly apply thread sealant and to not overtighten and that’s worked so far for me.

Slip fittings are harder to screw up due to the simplicity, except inyour case where you’re bonding two different materials.