trunking double sets

[davelerave]

hey

i'm going round a few walls in 3" steel and have to set out and back in again a few places about 100mm

or so


what's the best way to do this with manufactured bends thanks

and what do i need to link the trunking with(for continuity)thanks

 

[Dannyg83]

You can buy manufactured joining pieces

 

[benji]

manufactured bends every time ,you can buy earth links with trunking but if its galv. i can,t see why you need them you could check with trunking manufacturer

yours benji

 

[johnboy6083]

i have to agree with benji about bonding straps! a lot of sites go way over the top. a simple joiner should suffice.

 

[Sintra]

Personally i make sets and use bought 90 degree bends and always use the bonding straps.

 

[Guest123]

Manufactured bends come with trench plates anyway. I do add a serated washer aswell though as there is a bit of play in the holes.

 

[johnboy6083]

in theory, you could test for continuity at the end of the run of trunking and if you get continuity, job done! its not like anybody uses it as CPC anymore. well maybe some people do!

 

[Adam W]

If you're only setting out around 100mm and there a lot of sets to do you may be able to stand the trunking off from the wall with wooden or unistrut brackets and just do a straight run down the whole wall, depending on the circumstances.
Using 90 degree bends you would basically need 2 back to back, and might even need to trim them down, so it may be better to use 45 degree angles to create a smoother 'sweep' around the set cutting the internal corners, again depending on the circumstances.

 

[davelerave]

You can buy manufactured joining pieces

you mean the double set is manufactured??

 

[davelerave]

in theory, you could test for continuity at the end of the run of trunking and if you get continuity, job done! its not like anybody uses it as CPC anymore. well maybe some people do!

trunking takes the majority of fault current even with a separate cpc

 

[Dannyg83]

you mean the double set is manufactured??

No , you asked what to join the trunking with

 

[davelerave]

ok

i figure i'll 'set out' on each side with a 90 inside lid bend and back a straight piece onto them
if that makes sense

2 right angles per jump

 

[tonynulty]

If you are using 3inch trunking, cut trunking and leave the back on,dont cut off, on the front of the cut measure 1.5inches either side, mark and only cut off small flange sections, then fold trunking together untill small flange sections meet, drill and bolt other flange sections that have gone into each other.

this will give you 45degrees, then measure the distance for your set, if its 100mm put a straight edge on the small flange side of the trunking and measure 100mm at right angles from your straight edge up to your trunking on the 45degree set, this will be where you need to set back, mark and measure 1.5inches to the right of your original mark, and mark around trunking this is where you need to cut, leaving small flanges on, do not cut off,

from your cut measure 1.5inches to your right so you will have marks 1.5inches either side of your cut, cut out these areas on the back of the trunking, and again fold trunking together drill and bolt.

you should have a 100mm dog leg, measure the distance you need to dog back in and repeat the proceedure in reverse.

if you use 50mm trunking, 25mm either side will give you 45Deg, if you cut 50mm either side it will give you 90Deg best of luck, ive done hundreds of these its quite easy once you have done one.

 

[gaffer]

Thats how I do it Dave ,but not easy to describe.Next time I do one I'll take some photos as I do it.

 

[cantabrian9]

has this spark? ever used trunking before???