The subject tells it all. I've gone nearly blind googling for such a
thing so perhaps if someone knows of a supplier they could help.

I'm converting an old chandelier from candelabra bulbs and fittings to
regular medium base sockets. At the end of each arm there's a 4 inch
1/8" nipple brazed into the arm. I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread.

Everyone (including my local hardware store) sells NPT but this is a
tapered thread and I need a straight thread aka a "National Standard
Free-fitting Mechanical Pipe Thread".

Au contraire, Mon Frere!

The pipe die will do a great job as the pitch is the same. Just don't
screw it on too far. It's actually very difficult to get a straight die
of such large diameter and fine pitch to engage accurately enough to
repair the described thread damage. With the tapered thread die, the
taper guides engagement. File the sawed ends accurately square for
easier threading, and debur.

Doug Goncz
Replikon Research
Falls Church, VA 22044-0394

wrote:
... I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread. ...

Take the base of a socket and thread it onto the nipple before cutting.
Cut to length and unscrew the base - the cut threads will be
straightened. If you can put a slight chamfer on the cut end first, so
much the better. This always works for me.

Bob

wrote:
The subject tells it all. I've gone nearly blind googling for such a
thing so perhaps if someone knows of a supplier they could help.

I'm converting an old chandelier from candelabra bulbs and fittings to
regular medium base sockets. At the end of each arm there's a 4 inch
1/8" nipple brazed into the arm. I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread.

Everyone (including my local hardware store) sells NPT but this is a
tapered thread and I need a straight thread aka a "National Standard
Free-fitting Mechanical Pipe Thread".


Isn't a hex die, but if you get a Ridgid pipe threader (e.g. model 00-R or 12-R)
you can order 1/8-27 NPSM dies for it. Be warned, the pipe threader will cost
some moola, you will need a 1/8" drophead for it and then you'll have to order
the dies, but you will have a real nice threading tool.

GWE

An excellent suggestion. In fact, Email me with your mailing address and I
will mail you a few nuts that will work even better.
If all you want is to fresh out the threads at the end of the nipple, the
npt die will work just fine. The threads on these parts do not need to be
that accurate.

Also, realize that if you are upsizing the sockets, you may need to upsize
the wiring also. Often 20ga wire is used to feed candelabra sockets because
the bulbs tend to be of low wattage. With an Edison base socket, some nitwit
could fill it with 150 watt bulbs. Put 6 or 8 of em in a chandelier and that
20ga wire will be smokin' in no time.

Paul K. Dickman

"Bob Engelhardt" wrote in message
...
wrote:
... I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread. ...

Take the base of a socket and thread it onto the nipple before cutting.
Cut to length and unscrew the base - the cut threads will be straightened.
If you can put a slight chamfer on the cut end first, so much the better.
This always works for me.

Bob

wrote:

The subject tells it all. I've gone nearly blind googling for such a
thing so perhaps if someone knows of a supplier they could help.

I'm converting an old chandelier from candelabra bulbs and fittings to
regular medium base sockets. At the end of each arm there's a 4 inch
1/8" nipple brazed into the arm. I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread.

Everyone (including my local hardware store) sells NPT but this is a
tapered thread and I need a straight thread aka a "National Standard
Free-fitting Mechanical Pipe Thread".


Oh. I just reread your article. People are so freaked about cutting off threads!
You do *not* have to thread on a die first! The fastest way to dress cutoff
threads is with a belt sander or disk sander, just spin the part in your
fingers, held at a slight angle so as to impart a bevel to the threaded end, and
it will spin right on.

I recently was working on freeing a stuck spindle in a machine tool. The spindle
is threaded with a male thread on one end. I was tapping on the back end with a
lead hammer when suddenly it flew out the other end, doing a perfect nosedive
onto the floor, peening over the end threads nicely. Not to worry, I whipped out
my NES-1 rethreading tool, expanded the jaws, clamped it into the thread, and
backed it off, clearing most of the jammed thread. A few strokes with a thread
file, and the spindle was saved (WHEW!!!).

GWE

"Paul K. Dickman" wrote:

An excellent suggestion. In fact, Email me with your mailing address and I
will mail you a few nuts that will work even better.
If all you want is to fresh out the threads at the end of the nipple, the
npt die will work just fine. The threads on these parts do not need to be
that accurate.

The worrying factor is that the NPT die locks up on a brand new
nipple. Do you know if the smallest diameter on the NPT thread is the
same as the smallest diameter on the NPS thread? According to the guy
at Grand Brass (sells parts for chandeliers--see website) the reason
it locks up is because of the taper. The hardware guy with the NPT die
says that it locks because it's starting to cut the thread. On a new
nipple? The thread's already cut unless the smallest NPT thread is
smaller than the NPS thread.

And thanks but I have nuts.

Also, realize that if you are upsizing the sockets, you may need to upsize
the wiring also. Often 20ga wire is used to feed candelabra sockets because
the bulbs tend to be of low wattage. With an Edison base socket, some nitwit
could fill it with 150 watt bulbs. Put 6 or 8 of em in a chandelier and that
20ga wire will be smokin' in no time.

I've done a few of these jobs usually rewiring anyway because of the
deterioration of the insulation on the old wire. In this case the wire
is 18ga in the arms and 14ga from the center base to the hang chain
and is in good shape. Must have been rewired not long before I got it.
18ga will easily support 150 watt and 14 ga, 900 watt, but you'd be
silly to try and put in this high a wattage bulb. Far too glaring.

If the worst comes to the worst I'll clean up any damage with a file
(in addition to running a nut).

Thanks to everyone for their suggestions.

Paul K. Dickman

"Bob Engelhardt" wrote in message
...
wrote:
... I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread. ...

Take the base of a socket and thread it onto the nipple before cutting.
Cut to length and unscrew the base - the cut threads will be straightened.
If you can put a slight chamfer on the cut end first, so much the better.
This always works for me.

Bob

wrote in message
...
The worrying factor is that the NPT die locks up on a brand new
nipple. Do you know if the smallest diameter on the NPT thread is the
same as the smallest diameter on the NPS thread?


On my dies the pipes are slightly smaller but because of the inaccuracies of
both the tapered die and the nipple, your mileage might vary.


According to the guy
at Grand Brass (sells parts for chandeliers--see website) the reason
it locks up is because of the taper. The hardware guy with the NPT die
says that it locks because it's starting to cut the thread. On a new
nipple? The thread's already cut unless the smallest NPT thread is
smaller than the NPS thread.

They are probably both right, but if you are just knocking off the hacksaw
burr it probably shouldn't make much difference.


Also, realize that if you are upsizing the sockets, you may need to upsize
the wiring also. Often 20ga wire is used to feed candelabra sockets
because
the bulbs tend to be of low wattage. With an Edison base socket, some
nitwit
could fill it with 150 watt bulbs. Put 6 or 8 of em in a chandelier and
that
20ga wire will be smokin' in no time.

I've done a few of these jobs usually rewiring anyway because of the
deterioration of the insulation on the old wire. In this case the wire
is 18ga in the arms and 14ga from the center base to the hang chain
and is in good shape. Must have been rewired not long before I got it.
18ga will easily support 150 watt and 14 ga, 900 watt, but you'd be
silly to try and put in this high a wattage bulb. Far too glaring.

You seem to have a handle on it. It's just that the world is full of guys
who put pennies under fuses. You never know who the next guy will be.

Paul K. Dickman

wrote:
The subject tells it all. I've gone nearly blind googling for such a
thing so perhaps if someone knows of a supplier they could help.

I'm converting an old chandelier from candelabra bulbs and fittings to
regular medium base sockets. At the end of each arm there's a 4 inch
1/8" nipple brazed into the arm. I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread.

Everyone (including my local hardware store) sells NPT but this is a
tapered thread and I need a straight thread aka a "National Standard
Free-fitting Mechanical Pipe Thread".

Can't you use a round die?
http://www1.mscdirect.com/CGI/NNSRIT...2022&PMCTLG=00

wrote:
The subject tells it all. I've gone nearly blind googling for such a
thing so perhaps if someone knows of a supplier they could help.

I'm converting an old chandelier from candelabra bulbs and fittings to
regular medium base sockets. At the end of each arm there's a 4 inch
1/8" nipple brazed into the arm. I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread.

Everyone (including my local hardware store) sells NPT but this is a
tapered thread and I need a straight thread aka a "National Standard
Free-fitting Mechanical Pipe Thread".

hi, not quite sure what exactly you are sawing ....but if its possible
screw a nut on to the thread further up your uncut part and when you
have sawn part off then unscrew your nut and this will clean your
existing thread ,holy joe the holy one,happy new year
wrote:
The subject tells it all. I've gone nearly blind googling for such a
thing so perhaps if someone knows of a supplier they could help.

I'm converting an old chandelier from candelabra bulbs and fittings to
regular medium base sockets. At the end of each arm there's a 4 inch
1/8" nipple brazed into the arm. I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread.

Everyone (including my local hardware store) sells NPT but this is a
tapered thread and I need a straight thread aka a "National Standard
Free-fitting Mechanical Pipe Thread".

tomcas wrote:

wrote:
The subject tells it all. I've gone nearly blind googling for such a
thing so perhaps if someone knows of a supplier they could help.

I'm converting an old chandelier from candelabra bulbs and fittings to
regular medium base sockets. At the end of each arm there's a 4 inch
1/8" nipple brazed into the arm. I plan on cutting the nipple to about
1" with a hacksaw and anticipate some thread damage so I'd like to be
equipped to reform the thread.

Everyone (including my local hardware store) sells NPT but this is a
tapered thread and I need a straight thread aka a "National Standard
Free-fitting Mechanical Pipe Thread".

Can't you use a round die?
http://www1.mscdirect.com/CGI/NNSRIT...2022&PMCTLG=00

Why not? Great idea, thanks. And they actually deal with peasants such
as myself! I bought one.