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#51205 04/24/05 11:07 AM
Joined: Jul 2004
Posts: 19
L
Local Offline OP
Member
I recently finished up a company handout for Type MC and received a request for a handout on EMT.

For type MC I gave a run down of the basic tools of the trade specific to MC and a run down of the basic MC fittings. I included a few pages on code compliant installations and included the relevant text from the NEC. Topped the handout off with a paragraph about aesthetics. Simple, I work with MC quite a bit so I knew exactly what areas the guys were lacking in.

So now I'm sitting in front the computer and am unsure if there is really all that much to say about EMT. I'm not much of a pipe smith and have always delegated pipe jobs to the best pipe man on site at the time.

Any suggestions as to what standard tools of the trade would be?

Any good hints and advice I can put in my handout for novice benders?

Any suggestions or links that might help me complete this next handout?

I'm doing these handouts as a way to help improve my knowledge and understanding as well as those in the company who aren't afraid to learn or review. The boss gives me his blessing and gets the final review but the time and cost of material are on me. I only say this because I have put a little to much of myself and my money into a presentation quality handout and now a company newsletter every few weeks. I need to become more efficient at harvesting information and breaking it down into digestible chunks. I'd also love suggestions for interesting trade related articles for a small company newsletter.

almost forgot to run the spell checker...

[This message has been edited by Local (edited 04-24-2005).]

#51206 04/24/05 11:39 AM
Joined: Oct 2000
Posts: 4,116
Likes: 4
Member
Local,

# 1 point I would talk about the importance of using the proper tools in the proper manner to bend and cut to avoid kinks and sharp edges. Also sizing and laying out with the thought of easy pulling in mind.

Good Luck,
Bill


Bill
#51207 04/24/05 01:04 PM
Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
This link was posted here a while ago and it is a good start for a new "bender". http://www.porcupinepress.com/_bending/TheoryAndDrawings.htm


Greg Fretwell
#51208 04/24/05 01:40 PM
Joined: Aug 2003
Posts: 1,374
R
Moderator
One of the most important sections of the code, in my opinion, is 250.96:
Quote
(A) General. Metal raceways, cable trays, cable armor, cable sheath, enclosures, frames, fittings, and other metal non–current-carrying parts that are to serve as grounding conductors, with or without the use of supplementary equipment grounding conductors, shall be effectively bonded where necessary to ensure electrical continuity and the capacity to conduct safely any fault current likely to be imposed on them. Any nonconductive paint, enamel, or similar coating shall be removed at threads, contact points, and contact surfaces or be connected by means of fittings designed so as to make such removal unnecessary.

This section tells me that the EMT must be installed well enough that it is capable as serving as an EGC, whether that is your intention or not. That means that the installer must be very mindful about couplings and connectors being terminated well. For example, many people have a bad habit of tightening compression fittings by using only one set of channel-locks and not two. In my opinion, this would violate the above mentioned section, since it will be nearly impossible to get the proper effect of the fittings.


Ryan Jackson,
Salt Lake City
#51209 04/24/05 08:41 PM
Joined: Jun 2004
Posts: 92
P
Member
Agreement on the idea of planning runs with the latter possibility of pulling wires thru them in mind.

Marking should be done with a pencil. You can always tell an apprentice has done the conduit work because there are big, ugly Sharpie marks all over the place. However, a few misplaced bends for the benefit of the boneyard have reverted this requirement into using a simple dot with the Sharpie. This is a cool way to mark pipe.

The proper way to cut the conduit is to first use a tubing cutter to establish a perfect perpendicular circumference. Then cut it with a 32 tpi Lennox hacksaw blade. File off the tooth marks with a smooth file and then debur with a machinist's deburring tool [Vargus]. Or use a plumbers tapered reamer. Fillet the outer edges with a file. Use the finger test.

Theoretically or geometrically, a maximum of three 90º bends should ever be required. Lube the bends before they are installed. Label each conduit with contents: FIRE, ckt.#s, etc.

Survey the run for obstacles, support points and that stuff. Use super 90ºs and 22 1/2º bends in lieu of 30ºs. Saves 10º each time guaranteed. Also trips up those who try to match it with a future parallel run.

Use of "minnies" will obviate the use of box offsets. Insist on an enduting supply of all clamps [1 and 2 hole straps, Uni-strut straps, Caddy beam clamps, conduit nails {J shaped}, conduit hangers {"Minnies"} and tie wire, etc.]

~Peter

#51210 04/24/05 09:27 PM
Joined: Feb 2003
Posts: 687
A
Member
I use a marker on pipe more often because a pencil mark can too hard to locate in dim lighting.

For cutting there was another thread about this. Myself most metal saws will work. Not a tubing cutter person but it still has it's use.

For small pipe I like the reamer screw driver. I see more guys just use Chanel Locks.

Maybe you could list some pipe bending formulas.

The Bendfield book is also a good place to learn.

Tom

#51211 04/25/05 03:50 AM
Joined: May 2003
Posts: 2,876
E
e57 Offline
Member
EMT is kind of a broad subject.

Like everyone else, I would also emphisize proper sizing and planning of layouts. Not just a single run, but job wide. As it is esspecially important on larger conduit jobs. You can use line diagrams to layout everything from multiple runs, bends and every LB and junction box. You can have the whole job on paper before you start.

I have a handout for line diagrams: www.markhellerelectric.com/sld.doc
(I do these type of hand-outs too, but haven't one for conduit yet, so you're out of luck getting a freebie [Linked Image] Other-wise I'd just hand you one. )

I would then focus on production bending, and team bending. (this wont bore the people who know how to bend, but important information for all, novice or expert.)

For instance, most of the stuff here on this link was called out or all pre-measured by someone on a lift and bent by myself or one of my other guys on the ground. Then handed up, and installed. http://www.markhellerelectric.com/bar/bar.htm
By using an easy spacing configuration, (one inch or two inch) a guy on a lift can take one measurement, and the guy on the ground can add that one inch or two inch space for every 90 bend, and hand them up to be put in place.

Like I said, a broad subject, you could spend days on it. Other than proper measuring and bending technique, you could save some scrap from a few jobs and hand everyone a 3' piece to show off a trick or cheat.


Mark Heller
"Well - I oughta....." -Jackie Gleason
#51212 04/25/05 07:36 AM
Joined: Jul 2004
Posts: 19
L
Local Offline OP
Member
Excellent thoughts guys, I do appreciate any replies as this is usually all it takes to get me going. So I'm thinking:

Common tools and appropriate use (not a big deal here)
Proper bending methods (this is a big one for some of the guys)
Planing and Layout (very lacking in most runs here)
Aesthetics (ehhh, important but not overpowering)
Team Bending (A good explanation of how it's done will do wonders)
Common code violations and text of Article 358(2005NEC)

I think team bending is a good thought to run with. I know what normally happens here when a couple of guys "team bend" I think throwing that in right before code compliance will work nicely. Missing something still but that's OK. I'll figure it out before the month is out.

e57,
Nice pipe work!
I think I'll have to save your Line Diagram handout. Good information and I know myself and a couple of the apprentices will appreciate your line diagrams compared to what our designers have been giving us. In case you care I always give credit where credit is due and if I use you're handout in full or parts you'll get full credit.


Thanks again guys you've got my brain lubed now all I need is time to sit a write.

#51213 04/25/05 03:11 PM
Joined: Oct 2000
Posts: 2,723
Likes: 1
Broom Pusher and
Member
Mark (e57):

I really need to mention how impressed I am, by the materials you have compiled - the data, the examples, the "How-To" sheets; all for the assistance of the personnel in your firm.

Very well done!

Scott35


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
#51214 04/25/05 09:08 PM
Joined: May 2003
Posts: 2,876
E
e57 Offline
Member
Common tools and appropriate use (not a big deal here)
This is where a Bendfield guide is helpfull... But of course it does not list some of the tools used today, like a bandsaw for speedy clean cuts, lazer levels for replacing that old plumb bob, box off-set press, etc.)
Proper bending methods (this is a big one for some of the guys)
Another Benfield item for simple formulas, which are also printed on most benders, but can use some additions. Like: how to add a site notch to your bender, and chalk lines on the conduit to eliminate dog-legs.
Planing and Layout (very lacking in most runs here)
Line diagrams, but instead of just swinging the line, draw it in its actual path it will follow right on your scratch set.(or a peice of paper...)
Aesthetics (ehhh, important but not overpowering)
Simple... Level, square, straight, and plumb. Attention to those simple details makes a world of difference!
Team Bending (A good explanation of how it's done will do wonders)
Basic communication skills... "I want a box off-set, and a 90 at 32, and a 4" off-set to 20" from back of that 90." Point to it while you're saying it to the guy on the ground. You could also draw that profile (NTS) on a scrap paper. This saves the up and down travel of the lift, or some guy on the ladder, meanwhile he can be strapping the last run, or getting the next measurements.

Take this picture for instance: http://www.markhellerelectric.com/DSCN0013.JPG
I told one guy to start popping holes with 2" spacing on the gutter, and can. While he's popping holes, have a single set of measurements from the bottom hole on the can to the most right hole on the gutter. All of the 45's are the same, so 12" to one 45, 25" to the next, so I mark all 22 sticks, and bend all 22 with a magnetic protactor, I already measured the distance to the first 90. (lets say 30" from the back of the 1st 45.) I hand the conduit to my man Saul, he does a 90 at 30. We check for the first cut, then we add 2" to each succesive 90, and 2" to each cut for the whole first row. I'm done with the 45's so I start cutting and reaming. The guy popping holes isn't done yet, so we put connectors on them all, start on the second row. All of the connectors and couplings are on, the holes aren't done, we carry all the conduit in, already bent, and numbered and give them to the guy who isn't finish popping holes yet. He gets done, and starts putting the conduits in place. Total time 2.75 hours! Total man-hours 6.75! Well oiled machine = priceless! Thats just an example of how 2 experianced guys can divide the labor of bending, and hand it to an total novice to hang. The novice eventually gets a general idea of the system, and gets moved to cutting and reaming. Then doing some bends, then he's running the show...


Mark Heller
"Well - I oughta....." -Jackie Gleason

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