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Mike Manning
03-04-2017, 2:21 AM
I'm going to need to replace the power cord on the 1956 Delta band saw I'm currently restoring. First time I've done any of this. The band saw motor is rated at 3.85/7.7 amps and I assume that has something to do with the dual volt rating for 115/230. I don't know anything about electrical stuff. From an electrical perspective, I'm wondering what power cord I should use to replace it. I bought two today at big box store. A 16/3 cord rated for 13 amps and a 14/3 rated for 15 amps. I will be using 110/120 volt outlets at my house. I'm thinking I should probably use the heavier gauge cord just to be safe but I want to both be safe and optimize efficiency for my motor/HP/etc. Can anyone advise me who knows this stuff? If you just stayed at a Holiday Inn last night I appreciate it but looking for real expertise here. :-)

Thanks in advance!
Mike

PS After I do my band saw I'll start working on my jointer. I assume this advice will apply to the jointer as well.

Dave Stuve
03-04-2017, 3:00 AM
I'm not an expert, but I've done this kind of thing a few times.

Your motor's rating is for 110/220v operation, and the 220v amperage should be half of the 110's. So the rating is 7.7 amps for 110. At that rating, either 16 gauge or 14 gauge should be fine (motors usually take a few more amps when starting up, but I doubt more than the 13 that the 16 gauge can handle.) I use 14 gauge for a lot of things since it's the size you use for 15 amp loads. I usually look at 14 gauge wire and buy the most flexible / durable looking one.

Wire gauge has a lot to do with how long your wires can be. According to the chart I have, 16 gauge is good for 13 amps up to 25 feet. And 14 gauge is a big step up - 15 amps all the way out to 75 feet.

Good luck!

Mike Cutler
03-04-2017, 7:16 AM
Mike

Either will do it. Sounds like you have a 1/2 hp motor.
If the cords you bought don't already have molded plugs attached, you might find that the 14awg will give a better "bite" on a the plug you buy. The 16 will work also, but sometimes the amount of gap at the end of the screw/clamp doesn't facilitate clamping down real tight on smaller gauge cord, depending on the manufacturer of the plug. (This is all assuming that you have a reasonably long cord. ;))
The two amperage numbers are for the dual voltage rating. For the 120vac, it would be the 7.7 amps, as Dave pointed out.

mark kosse
03-04-2017, 7:19 AM
Howdy mike, while the 14 will be fine I've always put 12g on anything less than 1.5hp and 10g on anything up to 3. This comes from years of dealing with machines installed and wired by electricians. I don't believe I ever saw a "wired" machine with less than 12g. You can't go to big, within reason.

Jim Becker
03-04-2017, 9:50 AM
No harm in a little heavier than you actually need. I like using the rubber coated cord cable for this application and sturdy hardware on the wall end.

Mike Manning
03-04-2017, 11:53 AM
So thanks for all this feedback. The two cords/plugs I bought at big orange box store were Husky. Is there a brand that you guys prefer? The original cord, which I need to replace, as it had a nick which was just covered with electrician's tape, the rubber was still flexible. I'd love to have a nice cord like that within reason of course.

Darcy Warner
03-04-2017, 1:03 PM
Buy 10 feet of sjoo, buy a plug to put on it.

Jim Becker
03-04-2017, 8:29 PM
Buy 10 feet of sjoo, buy a plug to put on it.

This is my preferred way, too...better than the mass produced stuff, IMHO, and custom to the need for capacity, length and termination.

Steve Kohn
03-04-2017, 8:43 PM
I really like having the male end of the cord being factory molded onto the cord. I believe it gives me a better and safer male end. I will generally buy the correct gauge/length/plug combination extension cord and chop off the female end. It is usually easier and cheaper than buying all the parts separately.

Bob Michaels
03-04-2017, 10:11 PM
Buy 10 feet of sjoo, buy a plug to put on it.
I'm with Darcy...SJO cord is the way to go. I deplore inflexible cords and SJO is nice and flexible. Also agree with Jim, you can't go wrong with a heavier gauge wire. Even though 16 gauge may be technically acceptable, its very light gauge...it may have an acceptable jacket but the actual 16 gauge is what lamp cords are usually made of.

Frank Pratt
03-04-2017, 11:39 PM
You can buy far better cord ends than those that come on manufactured cords. Rubber cord such as SOOW or even SJO is also much better than the cable used in manufactured cords. Manufactured extension cords are cheaper, but you really do get what you pay for.


I really like having the male end of the cord being factory molded onto the cord. I believe it gives me a better and safer male end. I will generally buy the correct gauge/length/plug combination extension cord and chop off the female end. It is usually easier and cheaper than buying all the parts separately.

Dennis Yamamoto
03-05-2017, 12:52 AM
I just made a heavy duty extension cord and used a Hubbell 5266C 15 amp, 125 volt plug. It grips both the wires for good conduction, and the rubber jacket for strain relief.

Wayne Cannon
03-05-2017, 2:46 AM
I, too, find that heavy-duty 12 ga extension cords are significantly less extensive than purchasing the equivalent length of wire. They include two molded ends, which I typically use, despite their mass-produced crimped connections.

roger wiegand
03-05-2017, 4:46 AM
I like 12 ga SOOW cord for most everything. It's much tougher than most extension cords and 12 ga is good for up to 3hp 240v motors.

Dave Richards
03-05-2017, 6:14 AM
Whichever way you go, make sure you get the polarity right and connect the ground properly. If you've got or can get or borrow a multimeter, check that the ground resistance is no more than 0.5 Ohm.

Mason Truelove
03-05-2017, 9:01 AM
there is no harm of having an heavier gauge cord as long as what you have is not lesser than you need.

Darcy Warner
03-05-2017, 9:31 AM
I use buss drop for cord also, I try to make sure all cables are rated for 600v.

I also have to make sure I use the correct voltage twist lock, especially when I have 480 and 240

I tried a factory molded cord on one thing (worm drive saw) it was quickly replaced.

Ray Selinger
03-05-2017, 12:27 PM
I've found most of the insulation on the wire of the old machines I lug home to be crumbly . A spark in fine sawdust is something you don't want to think about !