Dry fitting PVC. What's the trick?

[mcleod]

I am replumbing the pump and filter setup. What is the trick to being able to pull apart dry fitted PVC? I've tried soapy water and WD-40. I can't. pull the Dang stuff apart and have resorted to pipe wrenches and/or hammers and screw drivers.

McLeod

 

[Bperry]

I am replumbing the pump and filter setup. What is the trick to being able to pull apart dry fitted PVC? I've tried soapy water and WD-40. I can't. pull the Dang stuff apart and have resorted to pipe wrenches and/or hammers and screw drivers.

McLeod

I’d like to learn too. I gave up on that a while ago and now just measure the socket depths and cut all the pipe on a miter saw to keep things square and predictable.

 

[mcleod]

I use a miter saw, too. I just can’t pull them apart after fitting together to glue

 

[oldprophet]

I use a miter saw, too. I just can’t pull them apart after fitting together to glue

Use a rubber mallet and large channel locks

 

[ajw22]

Prefit the pipe using soapy water to get full penetration. Then dry the pipes with a rag before putting on primer.

 

[jmastron]

I use a miter saw, too. I just can’t pull them apart after fitting together to glue

I've resigned myself to not relying on dry-fitting for accurate placement, just laying them connected loosely out for general location. Not only are they hard to get apart, but usually they don't go all the way together anyway until glued. I just measure everything, adding the socket depths and double checking before cutting. The calculator I use on my phone (RealCalc) helps -- it has good fraction entry/calculations (e.g. 2 3/16 + 7/8 + 7/8 = 3 15/16).

Prefit the pipe using soapy water to get full penetration. Then dry the pipes with a rag before putting on primer.

Will have to try this, makes sense that would help -- but doesn't the pipe slide out if you let go, like it does when you don't hold it together long enough for the cement to set?

 

[1poolman1]

I've resigned myself to not relying on dry-fitting for accurate placement, just laying them connected loosely out for general location. Not only are they hard to get apart, but usually they don't go all the way together anyway until glued. I just measure everything, adding the socket depths and double checking before cutting. The calculator I use on my phone (RealCalc) helps -- it has good fraction entry/calculations (e.g. 2 3/16 + 7/8 + 7/8 = 3 15/16).



Will have to try this, makes sense that would help -- but doesn't the pipe slide out if you let go, like it does when you don't hold it together long enough for the cement to set?

Pipes have straight walls, fittings are tapered, smaller the further in you go. That's why they get stuck when completely dry fit and they won't slip out when released. A tap with a pipe, wrench, hammer, Vise Grip, will separate them. It is the pressure of the glue in the fitting that will force them apart when gluing.
When cutting for a 90-degree fitting, just make sure the inside corners touch and the 90, or tee, will always fit. Works with a 45 as well, but it is a little difficult to line up that angle.
Using valves or sweep fittings will require measuring.

 

[ChrisLPC]

I loosely dry fit. Measure the pvc from elbow to elbow or coupling then add the depth of the full fit to the pvc. Most schedule 40 fittings I use are inch and a quarter for full fit. With the exception being couplers and tees.

 

[generessler]

Only option for parts already stuck is more force. I've needed to clamp the pipe in a vice; use a piece of 2x2 as a drift; drive it against the fitting edge. Unfortunately you're likely to damage either pipe or fitting or both.

Talcum/baby powder applied in advance has worked for me. Not perfect but way better than nothing. Best wash it out before gluing. I agree with those who say you can often get away without dry fits through careful measuring.

Before I stumbled on the powder trick, when I had a section that had to be just right, I'd sacrifice a piece of pipe. (For re-plumbing projects, use the old stuff.) Dry fit with only partial insertion in the sockets. Mark where the edges of the fittings fall. Finally cut the real piece by adding the extra length needed to get all the way into the sockets.

 

[mcleod]

I’d like to learn too. I gave up on that a while ago and now just measure the socket depths and cut all the pipe on a miter saw to keep things square and predictable.

Well,l as always, the insight and info are fabulous here on the forum. Thank you all. I have one more question. When I am going to glue are there considerations to be observed? Such as:

1. Prepping the pipes and the couplers before gluing.
2. Where to begin? Start at the pump and work toward the suction or return pipes or work from the pipes to the equipment?

McLeod

 

[1poolman1]

Well,l as always, the insight and info are fabulous here on the forum. Thank you all. I have one more question. When I am going to glue are there considerations to be observed? Such as:

1. Prepping the pipes and the couplers before gluing.
2. Where to begin? Start at the pump and work toward the suction or return pipes or work from the pipes to the equipment?

McLeod

Set the equipment in place where it will be easiest to service it. You need access to the pump to clean out the pot and to the MPV without having to step over a lot of pipe. If possible, leave the 10" of straight pipe, for 2" plumbing, into the suction port of the pump. The use of unions at the pump will make the install easier. Hi-temp unions are the best if the pump doesn't come with any. The filter should be full of sand and water so get it in place lined up where you want it, fill it, and plumb to it. Not fun trying to move a full sand filter after it is full.
I always use unions at the filter as well. Makes it easier to get into the filter if it ever needs to be done, which is very seldom with a sand filter.
In about 5 years you may have to add about 50#.

 

[ajw22]

Set the equipment in place where it will be easiest to service it. You need access to the pump to clean out the pot

Leave room behind the pump to pull out the motor and access the electrical box in the back. I see many pumps installed back against a wall and will be a real PITA when it needs maintenance.

Leave room between equipment for your feet to stand by each device.

 

[1poolman1]

Leave room behind the pump to pull out the motor and access the electrical box in the back. I see many pumps installed back against a wall and will be a real PITA when it needs maintenance.

Leave room between equipment for your feet to stand by each device.

+1. Unions on the pump mean that room behind it may not be an issue for service, but the fan needs clearance in order to keep the motor cool.

 

[mcleod]

Set the equipment in place where it will be easiest to service it. You need access to the pump to clean out the pot and to the MPV without having to step over a lot of pipe. If possible, leave the 10" of straight pipe, for 2" plumbing, into the suction port of the pump. The use of unions at the pump will make the install easier. Hi-temp unions are the best if the pump doesn't come with any. The filter should be full of sand and water so get it in place lined up where you want it, fill it, and plumb to it. Not fun trying to move a full sand filter after it is full.
I always use unions at the filter as well. Makes it easier to get into the filter if it ever needs to be done, which is very seldom with a sand filter.
In about 5 years you may have to add about 50#.

The sand filter was heavy. A shout out for CrossFit. I make it as level as possible then fill it directly with water? Remove the valve & add water from the top? Or add it through the inflow port? And to what water level?

McLeod

 

[1poolman1]

The sand filter was heavy. A shout out for CrossFit. I make it as level as possible then fill it directly with water? Remove the valve & add water from the top? Or add it through the inflow port? And to what water level?

McLeod

Before filling with sand, there should be water at least covering the laterals in the tank so that sand will flow under the lateral. I usually add more than that to be sure.
Yes, the valve is removed, the water added with a hose or bucket, the sand poured in, the valve re-installed, system plumbed, then you backwash the filter before using it to filter. There is a lot of very fine material in the sand that will get through the laterals and into the pool if the filter is not backwashed first. Watch the sight glass. It will look brown at first as that debris goes through, then it will appear white. That's when the backwash is done. Even then, you may get a little back into the pool, but not enough to worry about. You get used to it and your cleaner will clear it out.

 

[mcleod]

Before filling with sand, there should be water at least covering the laterals in the tank so that sand will flow under the lateral. I usually add more than that to be sure.
Yes, the valve is removed, the water added with a hose or bucket, the sand poured in, the valve re-installed, system plumbed, then you backwash the filter before using it to filter. There is a lot of very fine material in the sand that will get through the laterals and into the pool if the filter is not backwashed first. Watch the sight glass. It will look brown at first as that debris goes through, then it will appear white. That's when the backwash is done. Even then, you may get a little back into the pool, but not enough to worry about. You get used to it and your cleaner will clear it out.

the sand filter is existing so is the above procedure still in force?

 

[1poolman1]

the sand filter is existing so is the above procedure still in force?

If the filter is in place and filled, just plumb to it, yes.

 

[generessler]

Prepping the pipes and the couplers before gluing.

There are a gazzilon YouTube videos on gluing Schedule 40. Summary:

• Cut pipe square. Angles prevent full insertion into sockets.
• Ream out danglies from the inside. Keeps flow smooth.
• Slightly taper the last 1/8" of the outside. Prevents the end of the pipe from scraping all the glue out of the joint when pressing.
• Brush on primer with round-and-round strokes for 10 seconds or so to ensure 100% coverage. Both fitting and pipe.
• Within a few minutes, brush on glue the same way. Don't be stingy; not enough glue is a problem. But don't be sloppy either. Interior globs screw up flow. Exterior ones look bad.
• Push _all the way_ together. Don't be shy. This can take some force.
• Hold the joint 30 seconds. Otherwise they tend to back themselves apart.

One other note is that a few kinds of valves have CPVC bodies. The glue there is supposed to be formulated for CPVC. Many are PVC-only. Apparently pool professionals ignore this and seldom have problems. I guess due to low pressure of pool systems.

There are expensive tools, but for one pad they're overkill. Ideas:

• Cutting: Slide a slip coupler to the desired location. Mark all around with a sharp pencil. Cut the line with a hack saw. I find it a lot easier to rotate the pipe as I go, so I'm always cutting tangent to the line. Otherwise the blade wanders. With practice about 1 minute per cut.
• Reaming danglies and tapering: My $3 half-round file from a bin at Harbor Freight does fine. Handy for lots of other things, too.

 

[ajw22]

• Reaming danglies and tapering: My $3 half-round file from a bin at Harbor Freight does fine. Handy for lots of other things, too.

A Dremel tool with a sanding attachment can be faster and less work if you have lots to do.

 

[Newdude]

I carefully whack the big burrs with a sheetrock knife and then gently sand the rest with Plumbers cloth