Irradiated PVC hook up wire???

[Chuck H]

This stuff has been available for awhile. I often wondered why some of the PVC wire I got would shrink back and some would perform much better. With plain ol PVC you ALWAYS get loads of shrink back and you can't dare bump the wire with the tip of your iron or you get a charred hole in the insulation. But I have used PVC that had very low shrink and could take a bump with only a tiny dent. I had no idea these were two different PVC coatings!!! I chalked it up to "PVC is just crappy sometimes" and gave up on it in favor of more heat resistant (and much more expensive) insulations. But now, with some long overdue research, I'm finding that irradiated PVC is generally considered a good performer for hand work, with low shrink back and good heat resistance, and is dirt cheap when compared to more advanced materials. At US $14 for a 100' spool I'd like to try it and see if it's the better performing PVC wire I'm familiar with. But any experiences before I buy would be appreciated.

[big_teee]

This stuff has been available for awhile. I often wondered why some of the PVC wire I got would shrink back and some would perform much better. With plain ol PVC you ALWAYS get loads of shrink back and you can't dare bump the wire with the tip of your iron or you get a charred hole in the insulation. But I have used PVC that had very low shrink and could take a bump with only a tiny dent. I had no idea these were two different PVC coatings!!! I chalked it up to "PVC is just crappy sometimes" and gave up on it in favor of more heat resistant (and much more expensive) insulations. But now, with some long overdue research, I'm finding that irradiated PVC is generally considered a good performer for hand work, with low shrink back and good heat resistance, and is dirt cheap when compared to more advanced materials. At US $14 for a 100' spool I'd like to try it and see if it's the better performing PVC wire I'm familiar with. But any experiences before I buy would be appreciated.

I asked a similar question a year and a half ago, and got very little response.
http://music-electronics-forum.com/t26431/
T

[Chuck H]

Thanks? for the link. After some reading I think the "irratiated" stuff is what you run across in most big name, hand wired amps. Ever wonder why repairs on those amps seemed to go fine, but when you tried to wire your own stuff with fresh wire off the spool you get burn throughs and shrunk back, gooey joints!?! Well... My guess is that "PVC" was an easy enough to duplicate moniker without making it irradiated "PVC". So more profit to the manufacturer and seller. Even now, with the new coatings I cant find much comprehensive information to base a decision on. A couple of hours should be enough time to choose an insulation material! But it seems like different coatings spec different attributes and sometimes with different criteria. And it's just too time consuming and expensive to buy them all and try them.

I had another post about PTFE (Teflon) and silicone insulation. I hooked up a couple of really good sources for those insulation materials. About one third the price of Mouser for the same material! But irradiated PVC is about one third of THAT! I think I'll buy a 100' spool of each of my colors and give it a go. At US $85 (with shipping) for five 100' spools and the reports of acceptible performance I just have to see. Unless someone chimes in with a good reason not to. It'll be awhile, but I'll repost when I've tried the stuff.

[exclamationmark]

I haven't had any direct experience with irradiated PVC, but in theory it should be tougher. Irradiation is commonly used for lots of polymers to improve crosslinking - the melting temperature tends to increase and it becomes a lot stiffer. Of course the stiffness thing is a trade-off. It isn't so easy to say all PVC wire is the same as it really depends on the process that's used to make it. I've had 'regular' PVC that holds up fine to heating, and others where they actually melt into the shrinkage area, forming a sort of seal (it flows on top of the bare wire like some weird sort of plastic solder). Higher molecular weight PVC tends to be stiffer and generally quite resistant to most things (think PVC pipe). Crosslinking doesn't normally occur to a large degree in PVC, unless bombarded with an ion cannon during polymerization, and is more indicative of thermosetting plastic, which would be a good thing in the case of annoying shrinking wire.

[Chuck H]

+1
I've seen different behaviors with random and un-providential PVC as well. I mentioned older amps earlier. Marshall wire from the 70's seems quite flexible and yet it doesn't shrink back much at all! It still doesn't take a bump from an iron. The stiffer stuff seems even less prone to shrink and you'd have to actually hold your iron on it for a couple of seconds to make a fault in the insulation. And, as I also mentioned earlier, some of the newer stuff, and not all of it cheap, is stiffer than the stuff in vintage amps, shrinks back and chars instantly when bumped. God forbid you have a bend where the wire meets the joint or the isulation shrinks back and tries to straighten as the hot stranding cuts through it like a bread knife. Making a particularly ugly joint. I just gave up on the whole random crapshoot. But now I'm starting to consider the economy of the issue.

For PTFE wire the major distributors charge about 90 cents a foot for 22ga. (1kV) Independants sell the same stuff for as little as 35 cents a foot. I can live with that. But it's still $175+shipping for a five color kit of 100' spools. I can get the same kit in irradiated PVC (600V) for $70+shipping! And as long as the stuff is useable I don't see how PTFE makes the amps any better. I'd just like to know what I'm buying WRT the different PVC types. PVC being indicated as "irradiated" is new to me. And I hope it's an indication that I'm buying the right stuff. Putting an end to the frustrations.

Hey, and while I'm at it... How come the thickness varies so much for different materials of the same rating? Isn't the actual distance of the internal lead from other electrical potentials the only factor? Why is 1kV PTFE insulation thinner than 600V PVC?!? Does PTFE have some property that trancends the spacial limitation of the rest of the physical world???

[defaced]

I wish I could help on your original question, but I've never played with irradiated PVC. That said, I started searching around (very briefly) and stumbled upon From PTFE Wire to Retractile Cable: Trust Daburn who carries it. I'd do a test run but their $50 minimum order is kinda hindering for a guy who might maybe use 20 feet in a year.

Hey, and while I'm at it... How come the thickness varies so much for different materials of the same rating? Isn't the actual distance of the internal lead from other electrical potentials the only factor? Why is 1kV PTFE insulation thinner than 600V PVC?!? Does PTFE have some property that trancends the spacial limitation of the rest of the physical world???

In order to punch through, you must make the material conduct. Some materials don't conduct as easily as others, so the thickness can be different. Insulator breakdown voltage : Physics Of Conductors And Insulators

[exclamationmark]

I have some 3kV(!) rated silicone wire that looks pretty much identical to normal PVC wire. The insulation actually seems to be a tad thinner somehow... I don't think PVC is a bad insulator, but it's physical properties are somewhat lacking which necessitate the thicker insulation (like poor abrasion resistance... and the whole melting thing). The breakdown voltage of PVC is roughly 10-15kV per millimetre, while the silicone stuff I have (and teflon too) is around 20kV per millimetre. Not much of a difference.

[HTH]

Can't comment on the irradiated PVC wire you're talking about, but I feel your pain with the shrinkback on PVC wire, it bugs the life out of me when wiring up.

I got some PTFE samples a while back and that stuff was a joy to wire with and also very easy to strip back.

When all my PVC wire is gone, I'll be getting PTFE despite the much higher cost.

[Chuck H]

I'll be getting PTFE despite the much higher cost.

You say that now! When you find yourself needing a new spool of every color you use (I use five) that $35 to $90 bucks a spool stacks up and $14 a spool starts looking pretty good. I placed the order with Daburn for irradiated PVC. 22ga. 600V. They have any color you might want, said to be shrink and heat resistant (which is fine. I don't actually need flame proof like PTFE) tinned stranded copper and only $14 for a 100' spool. If it works out I'm a happy guy. I'll repost when it arrives and I've had the chance to torture test it.

[big_teee]

You say that now! When you find yourself needing a new spool of every color you use (I use five) that $35 to $90 bucks a spool stacks up and $14 a spool starts looking pretty good. I placed the order with Daburn for irradiated PVC. 22ga. 600V. They have any color you might want, said to be shrink and heat resistant (which is fine. I don't actually need flame proof like PTFE) tinned stranded copper and only $14 for a 100' spool. If it works out I'm a happy guy. I'll repost when it arrives and I've had the chance to torture test it.

Do you know if the wire is pretinned, like topcoat?

[Chuck H]

I don't know how the "topcoat" is tinned. The Daburn site only says "tinned copper" with no elaboration. Which is fine by me. I've wired amps with silicone test lead wire (butload of untinned strands). Very time consuming to soak and flow all the stripped ends before inserting to an eyelet or pot lug. But it seemed like a good precaution to take. Also, the likelihood of stray strands increases with fine, untinned stranding. At least IMHE.

[big_teee]

I don't know how the "topcoat" is tinned. The Daburn site only says "tinned copper" with no elaboration. Which is fine by me. I've wired amps with silicone test lead wire (butload of untinned strands). Very time consuming to soak and flow all the stripped ends before inserting to an eyelet or pot lug. But it seemed like a good precaution to take. Also, the likelihood of stray strands increases with fine, untinned stranding. At least IMHE.

Yes the wire that Mojo sells is presolder tinned.
I love the inside wire, its the Insulation that sucks.
I always seem to bump it with the iron.
The cloth pushback wire I use on pickups is not presoldered.
The insulation on it is tough as nails.
T

[soundmasterg]

Chuck,

I've used some of the irradiated stuff that Squires Electronics sells (the site I gave you in your previous link) and it works well. I am using up my stock of regular PVC and then I will be switching over to that. I have some teflon too but I feel the irradiated stuff is fine and I like the cheaper price and the fact that it strips easier too. Squires wire is pretinned too I think....and the insulation is much better than what CE or Mojo sells. I'm sure other suppliers have the good stuff too....

Greg

[Chuck H]

Ok... For anyone who still cares, this won't answer to much. But here goes.

The night I placed my order with Daburn I was surfing their site. Re-inspecting my ordered wire specs I noticed a small note in the description that said "UL 150V". WHAT!!! The UL code for the wire was 1429. That's indeed going to have "150V" printed on the wire itself. But, apparently, the mil spec for the same insulation thickness is 600V !?! So that's how Daburn advertises it. Doing some research I found that the insulation thickness on that wire is a mere .01" where the UL spec 1431 stuff that has "600V" printed on it has an insulation thickness of .033". Daburn was a little upset because they had already spooled my order and thought I was splitting hairs with the spec. I told them I would pay a restock fee and use the balance toward re-ordering a different spec wire. I just didn't want to use anemic looking wire. Even if it MIGHT work. I just have more confidence in the greater insulation thickness considering the spikes and bouncing differentials in tube amps. They were very nice and didn't charge me a restock fee. But, they don't have the UL spec 1431 wire. No one does in irradiated PVC. To get it you would need to commission it from a manufacturer. So I thought I was back to PTFE or silicone. But Daburn said that their regular PVC in UL 600V with the .033" insulation thickness is actually very good. And it was only US $15 for a 100' spool available in any color. So I took a chance and went with it to save some $$$. Now I have five 100' spools (different colors). It's the "proper" insulation thickness appearance wise. I did some initial testing with stripping and melting solder into the strands. I even touched the insulation with the iron tip for different amounts of time to see how long it would take to actually melt through it. So far this did seem to be the better PVC that I have encountered in vintage amps. So...

I put it through some hard paces today soldering ground buss (think three or four wires on a node and a hot iron). I have to say that this stuff performed admirably. Almost no shrink, handled some tight bends without spreading or cutting and just generally behaved exactly like the old school stuff you find in vintage amps. Of course it's no match for silicone or PTFE. And it has that PVC look when trying to route it where you want it (as in uncooperative). But I've worked with enough PVC to get over it. I'm happy with the performance and I only paid $15 a spool. So there you go. If you want very acceptable and inexpensive wire, Daburn has the old school "standard" PVC.

[big_teee]

Thanks Chuck:
Can you give us a link to the exact wire you ordered?
T