Knock Outs On A Surface Box

[1strangefish]

Hi Guys

Working on some surface mounted sockets when I realised I never found an easy way of doing the knockouts to feed in from trunking at the top. Ended up using a junior hacksaw and then nibbling with side cutters, managed to mangle a few in the process. Is there an easy way to do this without cracking the (very) brittle plastic?

Cheers

Fish

 

[androiduk2002]

2 Gang 32mm PVC Surface Box with Mini Trunking KO

Junior hacksaw and a file for me , the above link is for back boxes to suit mini trunking if you scroll down the page there is also adaptor , makes for a very neat job.

 

[pickleye]

You can buy the boxes with knock outs for mini trunking, also available with KO's for conduit. As androiduk says you can buy the adaptors (spouts) that fit in the knock out and house the end of the trunking.

I don't like the very brittle ones either, burst one the other day drilling it. Grrr

 

[m4tty]

Don't waste your time buying the cheap brittle plastic **** ones. Most wholesalers stock decent ones which are made from different plastic which are shatterproof. I had a nightmare the other week with one of the cheap crap ones. Never again will I buy these. Buy cheap ... Buy twice. Instead of

 

[pickleye]

Agree, Sadly gotta use what the boss has delivered. Worse yet when you get the right amount delivered, have no spares and one goes pop - learned that lesson a while ago now. Never again!

 

[kerching]

Mita MMB 251, 252, 252s...simples.

I use hundreds of them... :coat

 

[Sidewinder]

I do most of my domestic work in trunking, as it is normally temporary.

Long story, those who have followed my posts will know.

I only ever use the propper trunking boxes with the correct entries and the adaptors the ready formed bends etc.

Also the same for all plastic conduit installs I use the boxes with entries.

I use the MK system, as kerching says Mita have their own also.

You can even get them for ceiling roses.

I may go that way with the next EM light I hook up to this work, because at the moment I run the trunking carefully flush to the side of the fitting and finish off with caulk as it is hidden behind a counterbore.

The only time I use those horrendous brittle boxes and even the MK ones are brittle are with surface clipped T&E with surface accessories. Then its mini hacksaw & file, I tried a Fein type cutter nfg.

The only thing that works for me is abrasive type stuff, filing sanding, dremmel etc. after a few careful saw cuts.

The time it takes though is stupid to get it nice, and too much caulk is not good.

Especially as it is water based.

 

[batty]

I just use pliers have a few break but its rare.

 

[matt.leung]

Toolstation sell back boxes suited for trunking and conduit and they are pennies....

1G = .62 (41969) page 371

2G = 1.06 (53404) page 371

they are both 32mm deep

Toolstation

 

[1strangefish]

Hi Guys

Thanks for all the help. Did some more with a junior and small file and it worked a treat, then needed to open up an excisting one and . . . .POP. Customer left me a bit red faced as he had to give me a spare!

Uneven walls have also caused problems when is it tight enough to hold but not to tight to CRACK!

Once again thanks to all those who contributed

All the best

Fish

 

[ProDave]

Rather than standard back boxes, use the "conduit" ones.

apart from having round knock outs for conduit, the other main difference is the conduit back boxes are made of a much softer almost flexible plastic. So you can cut out whatever shape knock out you want without fear of them shattering, and if you tighten them down hard onto an uneven wall, they will just flex rather than shatter.

 

[M107]

+1^

 

[andy_spark]

Agree with Prodave, If I'm buying then decent conduit pattresses (MK) can do whatyou want with these cut, drill, holesaw etc. The ones my company gets are the very cheap and cheerful Volex with a knockout that barely lets a 2.5 T&E into it. I find on these cheap ones a quick snap with a pair of pliers into the box not away from it, and a smooth down with a stanley knife is sufficient, or file if it goes wrong!

 

[Phoenix]

Just an extra note for those that use MK trunking and bends, etc.... The own brand alto stuff from WF seems to be identifcal just in different packaging, wouldn't be supprised to find out that it all comes from the same place... would even put money on it (well 50p anyway )

 

[SPECIAL LOCATION]

... would even put money on it (well 50p anyway )

50p????????????

You just had six re-wires come-in ?