Monday, March 10, 2014

Strip Scrap Copper Wire



I have about 100' of thick black wire. It says #3 on it. I talked to the recycling center and they said I should try to strip the plastic off of the wire because then it is worth about a dollar more per pound. I have a few pounds here for sure!
I thought I would quickly slice the plastic with a razor knife... but that is not going so well.... I have stripped about 3 feet of wire, knicked the wire enuff to have copper bits and nearly took off a finger!
I am about to take the hit and turn it in the way it is, covered in plastic, unless somebody can help me out??
I looked online for 'wire stripper' and I get some electrican's hand tools and some really expensive machines designed for recycling. They start at about $1800!!!! I don't think I have that many pounds!!
Any good ideas?? (Besides burning, I think it will stink and probably get me arrested!)

It may be worth a try to drill a hole in a piece of scrap wood that's maybe a hair larger than the wire, and then drive a sharpened nail just into the hole, secure the wood and and pull it through?
Take a belt sander to it, then peel the rest?

Clamp the end in a vise and then stretch out as far as you have room. Hold the utility knife so that the cutting edge of the blade is away from the vise and the point of the blade is buried through the insulation all the way to the copper. Hold the knife and wire in both hands, fingers near the blade to steady it, and then walk backwards away from the vise. When you get as far away as you have room peel away the insulation, re-clamp the wire and do it again.
You MUST use a sharp blade and you may need to change it a few times before you are through. Be careful and you should be able to go through a hundred feet in a couple of hours. Take breaks if your hands start to cramp.

The other tip you can do is heat it up a bit with blowtorch it will soften up the plastque a bit and you can strip it pretty fast when it is warm.
Merci,Marc

When grandpa was in the scrap business he used to burn the insulation off, like you mentioned. Good ol' grandpa. Probably single-handedly responsible for global warming.

What Furd said and have a helper pull away gently on the plastic jacket as you cut so you will know when you have cut all the way through the jacket.

The razor knife in hand method scares me. That is basically what I have been trying, and it is too dangerous (for me). Heating it sounds OK, but now its a blow torch, and a razor knife
I kinda like the belt sander idea... How can I get the wire streched real nice and tight? Actually, that may be the real key to the whole thing... if it was taut, it would hold itself against the knife blade I bet.
Any ideas on strech the wire out?

Come-along, fence stretcher, truck bumper, boat winch, block and tackel, chain hoist.
How can I get the wire streched real nice and tight?

In Romania, I was at a huge state owned aggregate processing plant being remodeled. They had huge reels (4 diameter) copper wire.
The gypsies took it over for a long week end, which included a state holiday. They took the reels/spools and put them over charcoal to get rid of the wood and warm the wire. They then pulled the wire off the reel carcass and laid them in a long (1/4 mile) ditch with hot charcoal in it. They then just added more wire and more charcoal. In about a day, they uncovered everything and cut the wire into 20-30' lengths. they then could load it onto carts (rubber tired pulled by horses, mules and oxen) to transport it somewhere without the wood and insulation. - Sort of roasting a pig in a pit, but they had it planned and obviously done it before.
Dick

Dick...
I thought I was pretty well traveled...but DUDE!....I wish I had been in your suitcase....

I would stay away from heating the wire. These plastics give off fumes that are pretty awful and I certainly wouldn't want to breathe them for very long at all. Granted, I would take the wire out of the garage if it's especially cold and let it heat up to room temperature to make it all a bit more pliable.
I've seen people cut it into 1' lengths, then strip it with a pair of diagonal cutters or a normal wire stripper, but if it were me, I'd get myself a pair of those blue cut-proof gloves and a nice sharp utility knife. If you're careful, it should be relatively safe.
Good luck!

Gunguy45 -
I just stumble into these strange situations when and where I traveled - Just dumb luck. When I started on my series of travels, my friend said Be flexible and if it does not make sense, it must be true. There is a reason for things being done the way they are, because it does make sense for the situation, which you cannot change.
With the gypsies, they burned the reels and left them to start the charcoal for the trenches. Once the wires were in the long trenches, they left for a day or so to avoid the smells(pollution). If the state took over the project (not likely), they would just remove the wire in exchange for keeping it as scrap. - It made sense there at that time.
They always got the job because they camped near by and the nearest city was 30 miles away. The contractor doing the work was paid for labor and the owner/state provided the materials. This was not small diameter wire, but 1 -2 thick cables.
Zorfdt -
I agree about the smell and danger of the insulation burning not being good to be around for a long period. A long exterior area dissipates the odors pretty quickly, but is still not good to be in. Minimize the exposure.
Dick

If you clamp the wire firmly in a bench vise, it's pretty safe to use the utility knife method. Put on some heavy gloves and you will be just fine. You can strip several feet at a time, move the wire up and reclamp it. The insulation on #3 is thick enough that you won't be able to pull it off without cutting unless you have a cyborg arm.

I've stripped hundreds of feet of wire using the technique I described and never cut myself. I also have arthritic hands and don't use gloves. The trick is to secure the end of the wire in the vise and keep it taut with one hand while guiding the knife with the other hand. If you have enough room to stretch out ten or fifteen feet then it goes pretty quickly. As I stated, take your time, take breaks and it is not that bad a job for only a hundred feet.
Another way, if you have something like a woodworking draw knife is to secure the end in the vise, stretch out the wire and anchor it somehow, maybe to the bumper of the car. It doesn't have to be as taut as the previous method but it does have to be held above the ground. Straddle the wire and simply pull the draw knife as you walk backwards. Reclamp and continue until done.

I know this is an old topic, but still interesting and relevant...
I use a heat gun on low setting for multistrand stuff like speaker wire. The trick is to not heat it too much or else the insulation breaks off in small bits, but with a bit of practice you can pull off the insulation pretty quickly. I found using a knife tended to cut some of the strands. Haven't tried a blow torch but it sounds like it would be too hot and would tend to burn the insulation. The heat gun doesn't create any smell either, so you can use it indoors.
For small, single-strand stuff I find if you clamp one end in a vise and hold it taut with one hand you can scrape the insulation off pretty quickly with a utility knife. Don't cut into the insulation, just hold the knife at right-angle to the wire and scrape toward you. Safer, as you run less risk of cutting yourself.
WileE

Thanks wile..... Welcome and thanks for the additional comments.
Yes this thread is about 3 years old and it has run its course. I am closing this thread.






Tags: strip, scrap, copper, wire, pretty quickly, utility knife, away from, razor knife, away from vise, belt sander, blow torch, burn insulation, careful should, does make