Soft Plastic-Bodied Solenoids - How Do You Remove The Copper From Them?

Some solenoids have a hard plastic housing, and when crushed in a vice, the plastic shell breaks nicely, and one can remove the copper wire inside easily (like the black one sticking up further than the others on the left). Other solenoids, however, have a softer plastic housing that does not crack and break like the harder plastic ones do. The softer housing will deform without cracking. Cutting the solenoids in half is a messy job that causes copper windings to go flying. There must be an easier way to harvest the copper from these solenoids. Who has an effective method? When in the plastic housings, the solenoids only qualify as "copper motors" at my scrap yard, and go for about 25 cents a pound. Get the copper from them and throw it in the #2 copper bucket and your return goes up about ten fold, so as long as there's an easy way, it's worth it, right?

http://racer997.smugmug.com/photos/i...kH8BDLf-X3.jpg

What came to my mind was an experiment someone tried on something else. Don't recall if it worked or not, but it might be worth a shot. Maybe putting them in a freezer might cause the plastic to harden enough for you to crack them open in your vice. Try this at your own peril, I guess, because it's something I never tried myself so I have no idea how it might work.

2nd on the freezing or use a cutting blade on a Dremel.

I doubt a freezer would be cold enough. LN2 would easily do the trick - if I had some. Dry ice might be cold enough, perhaps, but that stuff's not cheap.

I put a couple on a metal rod a little while ago when I went home for lunch, and then took the propane torch to it. The plastic just melted off in minutes. I could probably do 100 or more solenoids an hour this way. When the plasitc was gone, there was left a nice roll of burnt copper on the rod. But is this burnt copper still #2?

Depends on your yard, some won't take burnt copper wire.

I do them on the spot. I stick a screwdriver into each end and bend it so it snaps in the centre. (across my lower chest outwards as they can slip & I gotta thing about eyesight).

That works for the harder plastic ones & only the really really soft ones cause any trouble.
The ends on the soft ones normally pop out, or just one end, then I grab the Copper wire & pull it out, take a few goes but I get almost all of it. Do 3 or 4 at a time. They seen to average 25 grams each.

Otherwise I save them up & do something similar but using a steel pin vertical in the bench vise & use a flat bladed screwdriver in the other end vertically.
I have a flat bladed screwdriver thats had the end of the blade broken off from using it as a lever & I find that works better on some of the solenoids.

Since they are soft shell another possibility is a "hot knife". Not one you stick in a fire, but one that you can plug in that is used for cutting nylon rope, cable, etc. You can get one from Harbor Freight for less than 10 bucks. I got one to cut up some 4 inch cargo straps to use as edge protectors for securing flatbed cargo, but have not gotten around to using it yet.

On the soft bodied solenoid I wait until I have accumulate 20 to 30 of them (enough worthy of my time). Set them in a old black baking pan I have, let the sun soften them up even more (1 or 2 hours). Take a sharp PVC cutter, cut the bottom off (1/8 of an inch). Take a dentist tool (don't know actual name), they have a "hook" on one end and a probing point on the other. Insert the "hooK" end into the copper wire, slight turn and pull motion is all you need to do. The PVC cutters cut through sun soften plastic, as if it was "butter". The PVC cutters and the dental tool is what I have found to be best technique for me. The solenoids with two tabs have one coil and the one's with three connection tabs have two separate coils in them. These type have a upper and lower coils with a plastic insulator in between them. Not a lot of copper unless you have a couple dozen to work, but copper is always better then nothing.

My short handled sledge take apart any of those soft or hard. Lol, plastic merely bending instead of breaking? **Hits harder!* * yeah baby!!

Its just a matter of bam bam bam! vs ''BAM! BAM! BAM! :D

BFH it!

It works, NA proved it!

So excited to share, she couldn't even spell! ;)

Sirscrapalot - All you need for happiness is a good gun, a good horse, and a good wife. - Daniel Boone

in my state we are not allowed to sale burnt copper wire....i was really threw off my game by this...i adapted and overcame...then the day came when it was time to clean my motors....ive always burned my motors over a fire in the summer or in the wood stove in the winter..i asked my yard and after speaking to the owner, they told me that as long as it was motor windings only they were fine with it being burnt...they went on to say the law states insulate copper wire cant be burnt ,,,so motors were fine.........

im sure this will vary from yard to yard,,,also if you do decide to burn them to clean them. use as small a fire as you can get by with....and burn small amounts at one time...when you are burning fine wire you will loose some if you build to big of a fire....

It doesn't matter what state you live in. Burning copper wire is illegal in any US state because it is covered by the Federal Clean Air Act. That's why the yards won't take them.

it may have always been illeagle to burn wire but it has only been a crime for the yards to buy it for about the last 2 years....at least in my state

Last night I spent sometime evaluating our different categories of scrap. We have accumulated several 5 gallon buckets of the little transformers. Also had a full bucket of solenoids, a mix of hard and soft body ones. Almost all of the hard body ones come from my landscape company. The soft body solenoids come from recycling of dumpster waste at the commercial business parks we manage. Have never sold scrap items in the category "copper bearing". Going to start though, as I don't see busting up the little transformers as productive and cost effective. What I'm going to do is evaluate the various copper bearing items, scraping methods, time, ease of recovery and percentage of copper return to actual weight.

I did several soft body solenoids (coils) last night and thought I would share what I found. We get about 10 to 15 of these a week, from a company that does appliance repair. I'm going to give only three types, the most common are from gas dryers and some gas stoves. They are mounted in pairs. The two connector coil weighed 1.10 ounces and the three connector coil was 1.59 ounces. The other type of solenoid is also very common, as it comes from refrigerator/freezer that have automatic ice makers. This coil weighed 1.31 ounces before copper removal. I'm giving just the actual coil weights and not the whole solenoid assembly that coil is part of.

Earlier in this thread I recommended setting them out in the sun for a couple of hours to soften. Well last night I didn't do that (no sun). What I found was the PVC cutters cut the soft bodied coils just as easy, so forget sun step! I do highly recommend the use of the PVC cutters and the dental tool. I didn't time myself, but I cut the bottom off each coil and removed the copper (about 1 minute per coil). I don't even try to recover every bit of the fine "angel hair" copper. A little copper is always stuck to the plastic body and that gets tossed into city recycle bin. The two connector (gas) coil copper weighed .83 ounces, the three connector (gas) was 1.26 ounces and ice maker coil was also .83 ounces of copper. I used the same formula for figuring copper percentage return on insulated wire. The percentage of copper return for each coil was: 75.4%, 79.2% and 63.3%. There is also a little bit of brass (the connectors) on each coil. The gas coil connectors are very small, weighing only .2 grams, so on the two connector gas coil you have .4 grams of brass. The ice maker coil connectors weigh .85 grams (1.7 grams per coil).

I will continue to process these coils for the copper. We get a lot of them (10 to 15 per week) for free, they are easy to process and copper return percentage is above 70%. I have read the past threads about these soft bodied coils. Most have said they are hard to work and use various techniques/tools. Some use hammer, hatchet, screw driver, chisel and suggest freezing. I'm not sure how/why we started setting them in the sun. Last night I learned that is a waste of time, also learned I need to review methods. The PVC cutter and dental tool is the way to process these coils. For me these little coils equal 25 to 35 pounds of #2 copper per year. More important they were going out with the trash and into a landfill.

fastest way
place solenoid on the floor-must be reinforced concrete or floor will crack
take a 4 pound hammer & give it a mighty smash
it should crack
then a few more good smashes and u should be able to tear apart the plastic coating with a pliers

works for me

u just have to be careful that the solenoid dont go flying off and hurt you or break something when u smash it with the hammer