Thread: gas pipe
View Single Post
  #3   Report Post  
noonenparticular
 
Posts: n/a
Default gas pipe


wrote in message
...
On Mon, 31 Oct 2005 09:24:06 -0700, "SQLit" wrote:


"noonenparticular" wrote in message
m...
Whenn measuring gas pipe for a new run, is the measurement taken from
the
inside of one corner to the inside of the next (ie: the pipe meets
inside
the elbow)? Is any extra length added to this measurement (ie: the
pipe
almost meets inside the elbow), other? What are the tricks of the trade

to
get the accurate measurement?

Thanks

jc


I measure inside to inside of the fittings.

The threads do not loose but a fraction of the length. ~ 1/16 inch


This is NOT correct. Half or three quarter inch pipes lose about one
half inch on each end if they are tightened properly into the
fittings. If you only enter 1/16", you will have severe leaking.

Just add an inch to the total length of the pipe and you can be pretty
accurate. Pipes do not need to be as precise as most amateur plumbers
think. There is generally a little "slack" in the measurements,
achieved by adjusting a few other fittings in the run. And, if you
are running a gas pipe for a kitchen range, who cares if it sticks out
of the floor by exactly 6 inches. 5 " works just as well, as does 7'.

The best way I have found to measure pipes is to simply hold the
fitting where I need it, measure to the next, and add an inch.

One other tip, if you dont have access to a pipe threader and have to
rely on the standard sizes sold at hardware stores (usually by the
foot or half foot), buy the longest piece, then use a coupler or union
and buy a nipple to make up the difference.

For example. You need 28 1/2 inches.
Buy a 24 inch, a coupler and a 5 inch nipple. (note, the coupler
itself adds enough to subtract the threads that go into itself. But
you still add the threads on the outer ends. If I am in one of the
rare predicaments where I have to be very precise, I will also buy a 4
inch and a 6 inch nipple. That way I use the one that fits the best
and later return the un-needed ones to the store. If you are still
off by up to 1/2". Simply use the longer nipple and tighten the
threads a little more.

Mark

Thanks Mark, this is exactly the help I needed.

regards,

jc