Take a look at this pipe:

http://tinypic.com/view.php?pic=4y60gaw

I need to flip the U-bend on the right hand side round, and take the
flow out into another pipe. Can I unweld any of those joints or are
the absolutely permenent?

If I can't, then the only thing I can think of is to cut the pipe at
the bottom of the short straight length of pipe (there's around 2
inches there to play with) that goes into the right hand side of the U-
bend. Then cut off the U-bend and stop it, and add another U-bend the
other side. Sound ok?

dean writes:

Can I unweld any of those joints or are the absolutely permenent?

If you can sacrifice the outer part (the U-bend here), it usually can be
cut and carefully peeled off, and the remainder cleaned up for re-gluing.

PVC pipe solvent "welding" is not really welded, just glued with solvent
penetration.

On May 29, 2:38 am, Richard J Kinch wrote:
dean writes:
Can I unweld any of those joints or are the absolutely permenent?

If you can sacrifice the outer part (the U-bend here), it usually can be
cut and carefully peeled off, and the remainder cleaned up for re-gluing.

PVC pipe solvent "welding" is not really welded, just glued with solvent
penetration.

more like fused or "melded" : ) ...no glue or adhesive used.
it's closer to welding than gluing...if you think about it!

p_z

On May 28, 10:32 pm, dean wrote:
Take a look at this pipe:

http://tinypic.com/view.php?pic=4y60gaw

I need to flip the U-bend on the right hand side round, and take the
flow out into another pipe. Can I unweld any of those joints or are
the absolutely permenent?

If I can't, then the only thing I can think of is to cut the pipe at
the bottom of the short straight length of pipe (there's around 2
inches there to play with) that goes into the right hand side of the U-
bend. Then cut off the U-bend and stop it, and add another U-bend the
other side. Sound ok?

There's a nifty tool made to ream out plastic pipe joints for
reglueing sold at good hardware stores. Ask there. Tom

On Mon, 28 May 2007 22:32:04 -0700, dean wrote:

Take a look at this pipe:

http://tinypic.com/view.php?pic=4y60gaw

I need to flip the U-bend on the right hand side round, and take the
flow out into another pipe. Can I unweld any of those joints or are
the absolutely permenent?

If I can't, then the only thing I can think of is to cut the pipe at
the bottom of the short straight length of pipe (there's around 2
inches there to play with) that goes into the right hand side of the U-
bend. Then cut off the U-bend and stop it, and add another U-bend the
other side. Sound ok?

I have always been able to with enough torque. But I wouldn't start a
fight. If its a tight space and I probably can't torque it, I'd just cut
it and buy a new piece. Time is money.

On May 28, 10:32 pm, dean wrote:
Take a look at this pipe:

http://tinypic.com/view.php?pic=4y60gaw

I need to flip the U-bend on the right hand side round, and take the
flow out into another pipe. Can I unweld any of those joints or are
the absolutely permenent?

If I can't, then the only thing I can think of is to cut the pipe at
the bottom of the short straight length of pipe (there's around 2
inches there to play with) that goes into the right hand side of the U-
bend. Then cut off the U-bend and stop it, and add another U-bend the
other side. Sound ok?

The drain pipe is ABS not PVC and if it was 'glued' correctly, no you
can't undo it. Be sure to use the right type 'glue' when redoing.

Harry K

On May 29, 4:27 am, tom wrote:
On May 28, 10:32 pm, dean wrote:

Take a look at this pipe:

http://tinypic.com/view.php?pic=4y60gaw

I need to flip the U-bend on the right hand side round, and take the
flow out into another pipe. Can I unweld any of those joints or are
the absolutely permenent?

If I can't, then the only thing I can think of is to cut the pipe at
the bottom of the short straight length of pipe (there's around 2
inches there to play with) that goes into the right hand side of the U-
bend. Then cut off the U-bend and stop it, and add another U-bend the
other side. Sound ok?

There's a nifty tool made to ream out plastic pipe joints for
reglueing sold at good hardware stores. Ask there. Tom

That requires cutting off the fitting to begin with. I really have
never seen a reason to do that other than to fix a pipe that has
broken at the fitting. Given room to work, just cut out the problem
and replace. Those fitting are in the 'cheap' range.

Harry K

"Harry K" wrote in message
ups.com...
On May 28, 10:32 pm, dean wrote:
Take a look at this pipe:

http://tinypic.com/view.php?pic=4y60gaw

I need to flip the U-bend on the right hand side round, and take the
flow out into another pipe. Can I unweld any of those joints or are
the absolutely permenent?

If I can't, then the only thing I can think of is to cut the pipe at
the bottom of the short straight length of pipe (there's around 2
inches there to play with) that goes into the right hand side of the U-
bend. Then cut off the U-bend and stop it, and add another U-bend the
other side. Sound ok?

The drain pipe is ABS not PVC and if it was 'glued' correctly, no you
can't undo it. Be sure to use the right type 'glue' when redoing.

DWV pipe can be either black ABS or white PVC depending on the code for the
local jurisdiction. Much of the US uses PVC, here in Ontario, Canada ABS is
mandated but PVC is used for underground piping which makes for some
interesting interconnections.

Interesting to note that when Home Depot opened here in Canada, the first
time I visited a store they had only PVC DWV piping, which was illegal. This
didn't last, but it took a couple of weeks before they actually replaced
their stock with ABS.

PVC pipe solvent "welding" is not really welded, just glued with solvent
penetration.

more like fused or "melded" : ) ...no glue or adhesive used.

Huh? PVC cement is a solvent glue.

it's closer to welding than gluing...if you think about it!

No. "Welding" is the fusion of the same materials. PVC cement is not PVC,
so it is not at all like welding, because the joint filler material differs
from the bulk material. More like brazing or soldering, if you want to
analogize.

On May 30, 12:19 am, Richard J Kinch wrote:
PVC pipe solvent "welding" is not really welded, just glued with solvent
penetration.

more like fused or "melded" : ) ...no glue or adhesive used.

Huh? PVC cement is a solvent glue.

it's closer to welding than gluing...if you think about it!

No. "Welding" is the fusion of the same materials. PVC cement is not PVC,
so it is not at all like welding, because the joint filler material differs
from the bulk material. More like brazing or soldering, if you want to
analogize.

The solvent melts the plastic so that it fuses to itself. The solvent
acts as heat to soften the PVC. That is not a glue property...with all
do respect.

The solvent melts the plastic so that it fuses to itself.

If you peel a joint apart, it is apparent that the only fusion is between
the cement filler (not PVC) and the bulk PVC, and that the depth of
penetration is very shallow.

"Richard J Kinch" wrote in message
. ..
The solvent melts the plastic so that it fuses to itself.

If you peel a joint apart, it is apparent that the only fusion is between
the cement filler (not PVC) and the bulk PVC, and that the depth of
penetration is very shallow.

If you peel a joint apart, then it wasn't a good joint to begin with.

The fusion is just that, the solvent and PVC become one and the same...
there is nothing to separate.

Noozer writes:

If you peel a joint apart, then it wasn't a good joint to begin with.

Polymerization is quite weaker in the solvated portion versus the original
bulk. With some destruction, the components tend to separate there.