Need tip on deburring fmc

[DPW]

Whenever we cut flexible metal conduit (FMC), we get some edges / burrs. Even after using a file, there are sharp edges left. Typical sizes cut range from 1/2" - 2".

How should one prevent these sharp edges from cutting into the conductors?

Is there such a thing as a FMC grommet or some kind of plastic cap?

 

[hillbilly]

What type of fittings are you using?

steve

 

[DPW]

Need tip on deburring FMC

Need tip on deburring FMC

For sizes less than 1", we use the screw-in zinc diecast and the compression style for 90 degree fittings. Our concern is whenever we use the compression style fitting.

 

[Kdog76]

How are you cutting the FMC? I typically snap it (overbend it) where I need it to break, and use a diaganol cutters to cut it and needlenose pliers to get the factory bend back in there... NO burrs no sharp edges doing it that way...

 

[Smart $]

How are you cutting the FMC? I typically snap it (overbend it) where I need it to break, and use a diaganol cutters to cut it and needlenose pliers to get the factory bend back in there... NO burrs no sharp edges doing it that way...

I use these to cut it...

Klein 1104 - All-Purpose Shears and BX Cutter

 

[tom baker]

There is an insert bushing to put in the end of the flex. Some of the clamp type fittings have a small hole so the bushing can be seen. The bushing used to be called a redhead.

 

[ultramegabob]

There is an insert bushing to put in the end of the flex. Some of the clamp type fittings have a small hole so the bushing can be seen. The bushing used to be called a redhead.

I have heard them called redheads, anti-shorts, and some guys call them Annies Shorts

 

[dcspector]

I have heard them called redheads, anti-shorts, and some guys call them Annies Shorts

Anti short is the definition. Also we always used a Porta Band to cut FMC. Sorry, but was a clean cut inserted the bushing and called a day. Disagree with me that is fine but that is how we did it. Old school I guess.

 

[cycotcskir]

Redheads are made large enough, so that would probably be the easiest way. It's probably going to work better than flaring the edge out with pliers.:roll:

 

[RUWired]

I have heard them called redheads, anti-shorts, and some guys call them Annies Shorts

and also insuliner sleeves (1/2" and up)

 

[220/221]

How are you cutting the FMC? I typically snap it (overbend it) where I need it to break, and use a diaganol cutters to cut it and needlenose pliers to get the factory bend back in there... NO burrs no sharp edges doing it that way...

Wire strippers work better than dikes on 1/2 or 3/4". Put one end all the way inside the flex and squeeze. It only cuts the first ridge and doesn't bend anything out of shape.

On bigger flex, I deburr with a razor knife.

 

[al hildenbrand]

For sizes less than 1", we use the screw-in zinc diecast and the compression style for 90 degree fittings. Our concern is whenever we use the compression style fitting.

In my experience, there is a grove inside the fitting (at least the ones I use) that the FMC settles into. I make it a point to cut the end of the flex to be square so it sets up against the grove. I've used the Benfield Saw-Box for all these cuts, with rare exception.

To deburr, I use a plain old eight inch slip joint plier. An old Iron Range electrician once taught me that the only reason the cross-hatch is on the handles of these pliers is for de-burring. :smile: Slip the plier jaws wide, then shove the handles inside the conduit and twist.

That said, with FMC and 90 degree connectors, how do you deal with pulling through the elbow with respect to 310.18 ?

 

[dcspector]

Al was that 300.18?

 

[al hildenbrand]

Al was that 300.18?

Oops!

You Betcha! 300.18. Raceway installed as a complete system. Thanks!

:smile:

 

[dcspector]

Al I knew exactly what you were talking about. Now what did I do with my AARP card......:grin: Just kidding.

 

[cycotcskir]

Slip Joints!:grin:

Most guys that I've worked with don't carry them. I'm not saying it doesn't work, though.

I always carried more tools than the guys I worked with and I never had a use for them. Well, at least not something that I couldn't do equally well with other tools.

What do you usually use them for?

And don't say deburring!:grin::grin:

I do have a set or two in my automobile tools, though.

 

[al hildenbrand]

Slip Joints!:grin:

What do you usually use them for?

For assembly of small branch circuit FMC, EMT. Nothing like them to set the locknuts. . . . and, [whisper]de-burring[/whisper]. One tool fits all in that situation, for me.

 

[LarryFine]

How are you cutting the FMC? I typically snap it (overbend it) where I need it to break, and use a diaganol cutters to cut it and needlenose pliers to get the factory bend back in there... NO burrs no sharp edges doing it that way...

That's what I do. I can often bend the metal sharply and then bend it back and forth until it breaks - no burrs.

I always use bushings for anything I put wires into myself.

 

[LarryFine]

That said, with FMC and 90 degree connectors, how do you deal with pulling through the elbow with respect to 310.18 ?

Because I pull the wires in, bend a 90 in the wires, then assemble the connector.



So, sue me.

 

[LarryFine]

I just looked it up. My take on 348.42 makes it apparent that it's okay to feed conductors before assembling (or after disassembling) angle connectors. It's like an accessible raceway cover.