Is there a slow-set PVC glue?

[dfleary]

I'm attempting to plumb the lines from my return pump up to the display tank using schedule 40 PVC, slip fittings, and Oatey #30818 "All Purpose Cement" (red & white container).

I can dry-fit everything together well enough, but when cementing the PVC together, by the time I get the primer on the PVC and fitting, then put the glue on them and finally insert the PVC into the fittings (in an awkward space inside the tank stand, mind you), there is literally only about 1 second in which I can tweak the fittings' angles, etc.

I've tried in vain two days in a row to put together the PVC that will connect the return pump to the hole in the back of the stand that leads to the external return assembly. - I spend an hour and a half working on it, then trash it and have to walk away for the night - my temper just can't handle all that tedious work ending up in a "close but no cigar" type of result that I just throw into the trash. :headwalls:

The angles are always off just a little, and it seems that when I want to simply connect two fittings together with a small ~2" piece of PVC, sometimes the PVC will slip into the fitting further than at other times. :furious:

1. Is there a slower-setting PVC glue?

2. Is there a rule of thumb for determining the length of a piece of PVC which has the sole purpose of connecting together two fittings as closely as possible?

3. Any other hints & tips would be greatly appreciated.

I want the plumbing job to look good, but after too many more of these "learning sessions," I'm going to have to resort to spa-flex instead of hard PVC!

[Wills612]

When you dry fit make little lines that go from the fitting to the pipe, so when you go to glue you have those reference marks. Also mark the desired end position so you dot slide your fitting on to far or short.

[uncleof6]

When you dry fit make little lines that go from the fitting to the pipe, so when you go to glue you have those reference marks. Also mark the desired end position so you dot slide your fitting on to far or short.

That does not work out so well, and leads to poorly glued joins, as the pipe needs the full depth of the fitting for a good join. Dry fitting does not achieve the same depth, because it will lock up before it bottoms out.

Assembling these systems is a skill. Learn the dimensions of the fittings, measure three times, and cut once—and fully seat the pipe in the fitting and make sure it stays put.

[Wills612]

That does not work out so well, and leads to poorly glued joins, as the pipe needs the full depth of the fitting for a good join. Dry fitting does not achieve the same depth, because it will lock up before it bottoms out.

Assembling these systems is a skill. Learn the dimensions of the fittings, measure three times, and cut once—and fully seat the pipe in the fitting and make sure it stays put.

Your right the pipe "should" bottom out in the fitting. I've done quite a bit of PVC and sometimes you just can't get it to seat all the way. I've never had a glued pvc fitting leak. As long as I see a consistent bead of glue form around the fitting after the pipe is pushed in I'm comfortable with it.

[Ucyibd1]

Measure the depth of the socket on the fitting you are gluing into and add that depth to the length of the piece of pipe you need.....for example, if you need 12" of pipe between your fittings and the depth of the socket on each fitting is 1", your overall pipe length should be 14". That ensures that you are getting full penetration into each fitting. Make sure you are putting a slight bevel on each end of the pipe you are gluing, if you try to just cut the pipe and use it without putting the bevel on it, the piece of pipe will remove all the glue as you push it into the fitting. That should give you more time to turn the pipe to where you need it. Make sure you are using plenty of glue on each joint, you can always wipe the excess off and that also helps keep the joint workable until it starts drying.

[Gorgok]

Unions can also be helpful between some bends so that you can change their relative angles if that is what is causing issues. Though for angles i mark a line on both fitting and pipe that as long as i align them up again then the angles should remain correct.

[dfleary]

Thanks for the replies, everyone.

I did take the advice of drawing lines on the pipes and I also did a little research and found that the Oatey Medium Grey Glue (#30884) *does* in fact set a little slower. It gives you a few more seconds to adjust things.

There is also an Oatey "Fast Set Heavy Duty" Grey Glue - so be careful not to pick this one if your aim is to use a slower-setting glue.

Now, once I water-test the plumbing, if I find any leaks in slip-fit connections, is there anything that will patch it, rather than cutting pieces apart and re-doing it all over?

[tallball158]

Through my experiences with PVC, they usually don't leak. You would be surprised at how well PVC seals. As long as you get glue all the way around the pipe, it will not leak. I will use a generous amount of glue, and twist the pipe while I am seating it in the slip joint. The twisting motion will ensure that the glue is being evenly distributed.