Is 30W Soldering Iron enough for Cardas Binding Post work?

Gardenstater

This first one nearly kicked my butt. I thought my Radio Shack 30W iron would be enough but I *almost* didn't get the solder to flow here, and it came out a tad thicker than I wanted. This is Cardas 11.5AWG Litz so that conducts a lot of heat away as well. What iron wattage have people been successful with at doing this.

I used a couple scraps of Cardas 29AWG wire to bind the pre-tinned 11.5 Litz to the BP and used plenty of flux. Took maybe 5m to get it hot enough even with wood insulation in the vice jaws.

Any tricks?

pitdogg2

I use 75 watt station at 750°. Try heating the binding post up with a propane torch. You'll find it much easier. That if it was me I'd start over it screams cold solder joint.

Gardenstater

75W ahhh OK thank you. No wonder I had trouble. I don't think the pictures do it justice but it did flow. When I get the 75W iron perhaps I'll reflux it and reflow this one so it looks shinier. But it did flow out to thin sheet at the edges. Not like a bead of mercury on a surface at all. The exposed copper is the scrap cardas I used to bind it with, which I didn't remove the coating from, and therefore didn't accept the solder there.

PS: also it's nearly impossible to remove the coating of the litz right where the insulation starts and that's why solder didn't flow there as well. But the tinning was totally not cold and flowed great everywhere the coating was gone.

Thanks.

Gardenstater

One thing that does not please me about these Cardas BP's is that they give you a BRASS nut and only one of them!! I'm not going to all this expense and trouble to have a brass nut in the signal path. It's bad enough that every manufacturer's fastons apparently have to be made of brass, instead of something like tellurium copper or hard tempered copper.

One of the options I struggled with was getting some tellurium copper hex stock and making nuts from it on my micro lathe. Then I could just use a pair of nuts and ring terminals.

Gardenstater

I have this soldering station but like every Chinese made product I own it has stopped working properly. Apparently it is 60W but it was not up to this task

https://www.circuitspecialists.com/SMD-soldering-system-with-tweezers-and-iron.html

What would you think of this one....80W Weller. Don't want to spend too much because I may be able to repair my 60W soldering station:

https://www.amazon.com/Weller-SP80NUS-80-Watts-Soldering-Iron/dp/B00B3SG796/ref=sr_1_9?crid=ZEA575I8L4F&dchild=1&keywords=75w+soldering+iron&qid=1598226211&sprefix=75W+solderin,aps,146&sr=8-9

VR3

I've used a weller wes51, I believe for a decade, works great.

Solders anything!

pitdogg2

I've used several circuit specialist stations, I've nothing bad to say about them. Like @VR3 I've had mine going on a dacade and its soldered everything.
Yep I like Wellers too yet when I bought mine my kids were growing up and I had to compromise on some things.

Gardenstater

Thanks guys. I'm seeing lots of recent reviews where they report that inexpensive Weller failed on them (4 out of the 10 most recent reviews). So I have to keep looking. I guess you get what you pay for now more than ever.

msg

I've heard good things about the Hakko soldering stations.

Hey with that Litz stuff, is each strand coated?

xschop

I used a micro torch to solder some OFC to large binding posts in the past. Worked great.

Gardenstater

msg wrote: »

I've heard good things about the Hakko soldering stations.

Hey with that Litz stuff, is each strand coated?

It is indeed! Makes it a challenge. I'm using DarqueKnight technique he gave out which is to use a wire wheel in a die grinder. But be careful not to spin the Harbor Freight ones at too many rpm! I had one bend its shaft on startup and fling the wire head! To be fair the tool was on 30k rpm and they say 4500rpm max lol. I've been running them at 15000 for the small dia. ones and the large ones at 5000

pitdogg2

msg wrote: »

Hey with that Litz stuff, is each strand coated?

Yes each strand is enameled.

msg

Don't forget eye protection!

I ask this question because I happened across a similar frustration a few years ago while trying to repair some earbuds.

In short, I understand a cheap solder pot can burn off this insulation and also tin the wires. I'd have to review to make sure this technique works with a dense count Litz strand pack.

msg

Ha! I just read those RPM numbers again! Sheeze man, you're lucky that thing didn't kill a dog or cat!

Gardenstater

Yeah heh heh I don't have faith that the solder pot was capable of getting rid of that much polymer coating on that much of a Litz bundle, and in the few seconds it has to do so. I also wasn't thrilled with the excess solder it was leaving so I settled on the soldering iron and wire wheel prep methodology. It does work no matter how large the gauge and you have some control over how much solder gets applied. I like to twist the wires as tightly as humanly possible with a crimping tool.

As an aside, my Chinese made Solder Pot also failed anyway, after only a few uses!

Gardenstater

Here's what I measured on the Cardas 11.5AWG Litz. It was composed of 6 different concentric layers with decreasing wire dia's as you get towards the center:

Outer #1 CCW 18 x 0.012" dia. raw copper color
2 CW 17 x 0.009" raw copper color
3 CCW 20 x 0.007" raw copper color
4 CW 8 x 0.006" raw copper color
5 CCW 2 x 0.003" gold color
Inner #6 1 x 0.0045" black color

I haven't bothered doing the math to see if it really is 11.5AWG.....I sure hope so.

msg

Ahh, I see.
And I didn't realize you already tried a solder pot!

Interesting. I'll have to remember this for next time I need to remove strand insulation

Gardenstater

Yeah, so with this 11.5 Cardas you have 66 wires and like I said I twist them really really tightly. It just doesn't seem feasible to expect that polymer to escape from that tight bundle, or for that matter if it somehow did that means the bundle gets flung apart??.....I don't know just really skeptical of that and don't trust that the solder is really penetrating and bonding in that situation.

xschop

Wouldn't you need to chemically or heat-strip off the enamel coating to each strand?

Gardenstater

I don't know what chemical will work. I tried soaking an untwisted and spread out end in Paint Remover for hours and it had no effect. I'm sure there is some solvent that might do it but what? I believe it is some polymer and may be impervious to most solvents. It is not polyurethane or enamel paint, that much I do know.

I have actually been trying to burn the wires a bit over my gas range for a bit but the wires get very hot very quickly and I don't want to destroy the coating further up the wire, so I do that very sparingly and blow on it every few seconds. I think it helps prior to the wire wheeling but that is what gets the majority off without destroying the wire.

xschop

Is your paint remover methylene chloride?
If so, then your coating is probably a polyamide.

Gardenstater

xschop wrote: »

Is your paint remover methylene chloride?
If so, then your coating is probably a polyamide.

I don't know but I'll check tomorrow.

anonymouse wrote: »

It all depends on how often you will be doing a job like this. You only need a high wattage unit for small jobs occasionally. If it were me, I would buy a high power cheap gun like this one https://www.harborfreight.com/100-watt-soldering-gun-kit-64056.html. It likely will not last, but it will definitely do for a few posts.

I was looking at that one and considering it. And if it suffers infant mortality it would be easy to return. I believe I have an old Weller Pistol type soldering iron like that in the garage and my next step will be to dig that one out and check the wattage and see if it still works. It probably was not made in China!

DarqueKnight

Gardenstater wrote: »

Yeah, so with this 11.5 Cardas you have 66 wires and like I said I twist them really really tightly. It just doesn't seem feasible to expect that polymer to escape from that tight bundle, or for that matter if it somehow did that means the bundle gets flung apart??.....I don't know just really skeptical of that and don't trust that the solder is really penetrating and bonding in that situation.

The copper wires heat up and assist in melting the polymer coating away. Solder can then flow into the spaces vacated by the polymer. In a tight bundle, unless you are applying some type of pressure, the twist is going to relax a bit due to heat expansion.

A solder pot is the method recommended by Cardas for their litz wire. In my experience, the solder pot method provided much higher conductivity compared to grinding off the insulation. I do not twist my litz wire ends prior to dipping in the solder pot.

The solder pot I use is the American Beauty Mini Pot.

For high heat, I use a very old Weller 8200N 100W/140W gun.
My soldering station is a very old Weller TC202 60W unit.
For lower heat work I use very old Radio Shack 15W and 40W pencils.

When I say "very old" when referring to the soldering tools, I am talking 20+ years.

machone

I have used a Weller soldering gun with no problems. Get in and get out.
Also used my soldering station/ iron. Just takes some practice and patience,

Gardenstater

Well I dug out the one I thought I still had, which must be more than 40 yrs old (so not made in China) and turns out to be the same one you have DarqueKnight! This should have enough power. I cleaned it up and straightened the bent tip and it seems to still work. I'll see if the tip has enough heat storage and conductivity for doing this job which involves a pretty big chunk of copper to heat locally and quickly:

Gardenstater

xschop wrote: »

Is your paint remover methylene chloride?
If so, then your coating is probably a polyamide.

Just checked. Savogran Stypeeze Paint & Varnish Remover, contains: Acetone, Toluol Petroleum Distillates, Methanol, Methylene Chloride.

Had no effect upon the coating on the Cardas Litz.

pitdogg2

The suggestion of a small propane torch was given to me directly from Cardas when I called them. I (like you) was having trouble with their RCA connectors making cables. They told me all they use are small propane torches to solder with. I use gold plated ring shanks with their binding posts, I find it much easier.

Gardenstater

I've emailed them just now asking for help with the jam nut issue. Only 1 brass unplated jam nut (they may be plating them now!?) supplied and asking about why we can't have tellurium copper which is what they use for the BP body and top nut.

Unfortunately I don't own one of those micro-torches. Seems like it might be a good investment.

PS: maybe my jam nut is gold plated but now they are plating them with the same sliver + rhodium flash, as well as the top nut (mine is gold plated) at least that's the way it looks in the picture:

http://www.cardas.com/ccrr_s.php

westmassguy

I've used this every day for over two years:
https://www.circuitspecialists.com/csi-premier-75w-Soldering-Station.html

It's on for hours at a time. Does everything I ask.

Gardenstater

Westmassguy that looks like a very nice one. Far more sophisticated than mine. I never got a manual for anything but the hot tweezers with mine. I got it on a huge discount for maybe $35 and never complained but it may have been a return or something.


My Ragtag Fleet of Soldering Equipment SMH

My Circuit Specialists 60W 950+ has always worked great until recently. Now it seems to not be able to get up to temperature or hold it steadily. So I dug out the Type K Thermocouple and even with the dial all the way up to 480 C at first I couldn't get it to read above maybe 206 C at the tip. So I pulled the rubber CAL plug and turned the screw all the way CW. Hardly makes any difference from fully CW to fully CCW...maybe 10 C if that. Then I started fiddling with the pins on the connector and pried on them a bit and got a tighter fit. No difference. Then I started fiddling with the output jack on the front panel and it is loose and could be turned a bit CW or CCW. Turned it fully CCW and managed to get the temp to shoot up to 300+ C. Seems to be a connection issue inside. I'll have to open it up and check all the wires and there are 6 pins.

The Radioshack 15W/30W iron got up to 390C tops. I guess that may be all it's capable of. Probably working ok, just not enough power for the current job.

The old Weller 8200N 100W/140W unit worked fine and on the 140W setting got up to a respectable 500 C. So that's what I'll be going with as Plan A but I have doubts about it's rate of thermal conductivity and the tip doesn't have much mass to it.

Dug out the old Benzomatic propane torch and was hopeful because it has a large beefy soldering tip attachment with it. NG. The valve assy must be clogged up with carbon or something. Couldn't light it. No sound of gas escaping even with a good tank that works with a friends torch. I may try disassembly and cleaning in the ultrasonic cleaner. Anyway I can put the soldering tip attachment on his torch and that can be Plan B, but I don't like that the flames come out albeit sideways. My wire and /or wood jaws on the vice could be in jeopardy. Using the flame directly may be another option but it is a large flame and can't be adjusted to a small one with my friend's torch anyway. I seem to remember my old one working better than that back in the day.

Gardenstater

So here's the Circuit Specialists solder station PCB and if these are not cold solder joints I don't know what is. Cleaned them with a Q-tip and Everclear 195 and will reflow the solder.