Les talks plastic pipes
We asked Les Zell, our resident
master plumber, to tell us some
of his tips on working with plastic
plumbing. Not surprisingly,
with 25 years in the biz, he
had plenty to share. Here
are a few of his best.
Les on Plumbing Wisdom
learn 75 percent
they need to
the first year on
the job, but
that it takes 20
years to learn
the next 24
the rest is
Tip 1: Les is an ABS Guy
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Les with ABS plastic pipe
Les and his plumbing buddies all use ABS pipe for drain lines and plumbing vents.
“I pretty much only use ABS black pipe
and rarely use the white PVC stuff. It’s
all about the glue. Gluing ABS is a one-step
process, which makes it faster to
work with than PVC. Purple PVC
primer is messy, emits noxious fumes,
and it’s just ugly.”
ABS cement lasts longer in the can
and dries clear, making it more forgiving
if you get a drip or two on the
floor. ABS cement also dries faster,
which reduces the risk of connections
pushing apart before they set
up. Les believes the labor saved by
using ABS more than makes up for
the extra money spent on pipe
and fittings. ABS is also lighter
and more flexible. He says that
makes it easier to flex for bending
it into tight spaces.
“It’s not only me. None of my
plumber buddies use PVC either.”
The only downside—retailers
don’t always carry ABS.
Tip 2: Use dull blades for bigger or tighter cuts
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Cutting ABS with a dull wood blade
Dull wood blades cut ABS cleanly without chatter or melting the plastic.
When Les cuts larger pipe or has trouble getting the
tubing cutter (see Tip 11) into tight spaces, he uses a reciprocating
saw fitted with an older, dull wood blade. “A new wood
blade with aggressive teeth tends to grab on to the
pipe and rattle the whole works, and a metal blade
melts the plastic rather than cuts it.”
Tip 3: You can reuse a landlocked fitting
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Socket Saver tool
This special tool allows you to ream out old, glued-on pipe from a fitting and save the fitting for reuse.
If you have to replace some
piping but it’s tough to replace
the fitting, it’s possible to ream
out the old fitting and reuse it.
This happens a lot. Let’s say
there’s a tee coming out of the
back of a cabinet with a broken
pipe leading to it. Or the fitting is
so buried up in the floor joists
that you can’t get at it. Les just
cuts off the pipe near the
knuckle, then uses a Socket
Saver to ream out the pipe to
expose the inside of the fitting.
Then he can cement a new pipe
into the old fitting and reuse it.
“It’s a lot simpler than ripping
out cabinets or drywall or concrete
to replace the fitting.” Find
Socket Savers for $18 to $35 through our affiliation with amazon.com.
Tip 4: Don’t glue yourself into a corner
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Plan pipe assembly so you glue in the moveable pipes last.
In many assemblies, there
are pipes that move and
pipes that don’t. If you start
gluing fittings together willy-nilly,
you may end up in a situation
where you’re unable
to attach the last fitting
because one or both of the
pipes don’t move enough to
slide the fitting on.
“The last fitting to be
glued should be the one on
a pipe that has a little
wiggle room.” That’s usually
where a vertical run meets
a horizontal one so you can
snug on an elbow or a tee
from two directions.
Tip 5: Deburr for leak-free connections
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Deburring a plastic pipe
Scrape off burrs left from the saw with a utility knife.
Leftover burrs on the end of a pipe will create channels in the
cement when you push the fitting onto the pipe—and then stay
there like little canals. That’s when you’ll get leaks or flunk a pressure
test. Les always scrapes away burrs with a utility knife before
joining the pipes.
Tip 6: Avoid call-backs: Use straps
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Plastic strap supports
Use plastic straps rather the plastic J-hooks to support horizontal runs.
Changes in temperature can cause changes in the length of plastic
pipes. When you hang pipe from plastic J-hooks, you’ll hear a tick
when the pipe slips past the J-hook. Les says he gets tons of service
calls from panicky customers believing these ticks to be
water drips from a leaky pipe. “But they can never find the leak!”
He generally uses plastic straps and never gets false alarm
calls on his plumbing.
Tip 7: Learn Les’ elbow rule
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Pick the appropriate elbow depending upon pipe content (air or water) and water flow direction (horizontal or vertical).
For pipes under 3 in., there are three basic types of 90-degree elbows: vent, short
sweep and long sweep. Vent elbows are easily identified by their drastic bend and
can only be used on a vent run that carries air, not water.
Les has a good system to remember when to use the other two types of elbows. “If
water is speeding up as it turns the corner (usually going from horizontal to vertical),
use a short sweep. If water is slowing down (usually from vertical to horizontal), use
a long sweep.”
Tip 8: Skip those closet flange slots
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Toilet mounting flange
Mount the toilet flange with the notches parallel to the wall and avoid using the slots for the closet bolts.
Les has serviced dozens of toilets with broken
closet flanges. Toilets are top-heavy, which
stresses the closet bolts that hold a toilet to
the closet flange. The plastic on the sides of
the adjustable slots that receive the bolts is
thin and prone to cracking. Les always turns
the flange 90 degrees and anchors the toilet
using the notches instead. He makes sure the
notches are parallel to the wall behind the
toilet. “One more thing: Don’t use flanges with
metal collars—metal rusts.”
Tip 9: Support hot drain lines
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Support for hot drain lines
A 2-in. pipe supports the 1-1/2-in. drain line.
Drain lines that routinely drain extremely hot water need
continuous support. “Lines under sinks that are connected
to dishwashers are the most common culprit.”
Those pipes will sag between ordinary supports.
Here’s another Les trick: “Slide a larger pipe over the
drain line before attaching any fittings, and then attach
the supports to that.”
Tip 10: Seal the ends!
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Seal end cuts
Seal pipe ends with ABS cement.
Most ABS pipes have either a cellular
or a foam core that air will
actually pass right through. “If you
don’t believe it, wrap your lips
around the pipe wall and blow
through it.” If you don’t seal pipe
ends with cement, air will escape
into the porous center core and
find its way out of the plumbing
system and you’ll fail a pressure
test every time. “Can you even
imagine that disaster? You’d have
to replumb everything!”
Tip 11: Les loves tubing cutters
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This large-size tubing cutter cuts plastic pipe up to 2-in. in diameter.
For pipes up to 2-in., Les prefers a tubing cutter (a giant version of
the type used for copper tubing). “It makes a perfectly straight cut
with no burrs or shavings to clean up. But best of all, it doesn’t take
up much room in the tool bucket.” You can get them for about $25
at home centers.