What am I doing wrong?

[ColJack]

hence the lockring on a running coupler.. it pushes the coupler tight to one side of the thread if it's a loose fit..

 

[securespark]

Methinks Numerical Spark was referring to Ban's diagram, not to a running joint.

 

[ColJack]

he could put a lockring on that too though..

 

[partpdoctor]

hi bas
i served my time at the old electric board's training school and block release at tech......
the official thread technique is half forward and quarter back.....
now to whet your appetite, with 20mm conduit the three "magic measurements" for fabrication are 6mm, 16mm and 1 1/2 inches.......
i will leave you with that one

the man who taught me to bend was once the chief electrician on the QE2 and his saying was "Beware of the man with a mark on his former" i will leave you to mull that one over as well....
best wishes
alan

 

[partpdoctor]

on friday , i am doing a "pre AM2" tutorial with a student at my local college.
in the AM2 you have to install a single piece of tube with one set and two 90 degree bends between a trunking and light with pre drilled holes and fixed saddles ......
the kid gets the secret on friday......

 

[londonboy]

the kid gets the secret on friday

Cut it in half and stick a coupler in the middle!..
..Not that I did that in mine

 

[holmslaw]

..

 

[ban-all-sheds]

Can you get depth stops to fix round conduit? I'm envisaging a sturdy metal collar with a fixing screw you tighten by hand - slip it on at the right distance from the end depending on what length of thread you want, and when the cutter can go no further....

Just as an exercise - try cutting a thread on some PVC conduit.

BTW - tried that - the end of the conduit broke up.

 

[ColJack]

Can you get depth stops to fix round conduit? I'm envisaging a sturdy metal collar with a fixing screw you tighten by hand - slip it on at the right distance from the end depending on what length of thread you want, and when the cutter can go no further....

yes, it's called the pipe vice.. once you know the right distance, put it in the vice at that point and the vice will stop it..

Just as an exercise - try cutting a thread on some PVC conduit.

BTW - tried that - the end of the conduit broke up.

did you warm the conduit up a bit first? hold it between your legs for a few minutes to soften it a bit..

no idea on the magic measurements.. do it all by eye..

at a guess...
6mm would be the length to thread to put a female bush on the end of a conduit.
16mm sould be for a coupler
1 1/2 inches would be for a running coupler.
what's the fourth measurement then?
and these would only be valid for 20mm conduit as larger couplers are longer..

 

[ban-all-sheds]

yes, it's called the pipe vice.. once you know the right distance, put it in the vice at that point and the vice will stop it..

Ah - aint got one, and can't justify getting one. Oh well.

did you warm the conduit up a bit first?

No, but it was a hot day, the conduit wouldn't have been cold.

 

[NotHimAgain]

Can you get depth stops to fix round conduit? I'm envisaging a sturdy metal collar with a fixing screw you tighten by hand - slip it on at the right distance from the end depending on what length of thread you want, and when the cutter can go no further....

Just as an exercise - try cutting a thread on some PVC conduit.

BTW - tried that - the end of the conduit broke up.

You must be gentle BAS .

BTW you could use an ordinary vice and just crush the conduit in it as its only a test exercise.

 

[partpdoctor]

no idea on the magic measurements.. do it all by eye..

at a guess...
6mm would be the length to thread to put a female bush on the end of a conduit.
16mm sould be for a coupler
1 1/2 inches would be for a running coupler.
what's the fourth measurement then?
and these would only be valid for 20mm conduit as larger couplers are longer..

hi coljack
the 6mm is what you knock off the measurement to the back of a bend so the conduit will sit in a saddle
the 16mm is a thread or half a coupling
the 1 1/2 inch is what you knock off a box ( if doing a run with flourescent light on it with 600mm centres you knock off 3 inches-two boxes.
when you cut and thread the boxes will be at 600 mm centres.

 

[partpdoctor]

i served my time at the old electric board's training

That would explain your lack of knowledge re steel conduit.

now to whet your appetite, with 20mm conduit the three "magic measurements" for fabrication are 6mm, 16mm and 1 1/2 inches.......
i will leave you with that one

There are actually four "magic measurements" (as you call them) and you've got two of them wrong!

"Beware of the man with a mark on his former"

Utter rubbish

good evening holmlaw,

have i done something to offend you?
if i was unfortunate enough to be taught by the chief electrician on the QE2 at a multi million pound purpose built school and have been successfully installing all manner of containment since september 1981 i was wondering where you would get the ammunition to have a pop at me? this is a learning environment and i would be interested in a constructive explanation of your alternative installation methods to my "rubbish".
best wishes
alan

 

[RF Lighting]

It's just the way he is.

I have a mark on my former FWIW.

 

[ColJack]

I don't own a former.. but the ones at the places I end up working are usually old and have about 4 different marks on the former..
so I always do a test bend and work out the differenct to the back of the former and add that on...

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or use the setsquare method if measuring from the other end..
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