Soldering

DON73

I'm doing a little work on a pair of 7s and I need to solder wires from the crossover to the tweeter and woofer. The wires on the crossovers don't have the ends that fit on the speaker connectors so I thought I'd try to solder the wires directly. I have 3 irons, 2 from PE and a Weller. None of them will get hot enough to tin a wire much less solder wires to the speaker. What Iron do I need to get? I won't be doing a lot of soldering but if I do crossover work I need something that works and has a small enough point for small work. TIA

Fongolio

Pretty much any iron that can do 35 watts or more with a nice thin taper tip should do the job.

Outfitter03

If your iron is the above rating and you are still having problems it could be technique. You need to have a clean and freshly tinned tip. The problem may be getting good heat conduction from the solder tip to the wire. You need to start heating the wire, then melt a small amount of solder, even if it mean doing so on the iron to wet the area between the tip of the iron and the copper wire. The wire then should heat rapidly and the fresh solder be applied to the heated copper wire to tin.

It is sometimes difficult to raise the temperature of the item being soldered without this "liquid" bond. Doesn't take much!

Fongolio

Outfitter03 is right, and I missed that point, a clean tip is essential and will allow the proper temperatures to melt the solder. I always have a water soaked sponge to re-clean after every solder and on first heat up I clean the tip with a file cleaning card (very short length wire type brush). It works great to clean off the built up oxidization (black stuff) from the tip. I can always tell when it needs cleaning because it won't heat enough just like what you are experiencing.

Kelvin

On3s&Z3r0s

Totally agree that tinning the tip of the iron is key. I always try to get enough on so that the molten solder is touching both the solder pad on the board and the wire lead being soldered. Also, keep in mind that to make a good solder joint everything being soldered needs to get hot. So soldering to something like a speaker binding post is harder than soldering to a crossover PCB because there's more thermal mass to heat up. I try to make sure everything that can be unscrewed from a binding post before soldering is removed.

While we're on the topic of technique... do you all do anything in particular when desoldering using braid? I don't usually tin the tip in that case since the braid soaks up the tinning solder. But using one of the cheap Stahl soldering stations from PE I was having problems getting the joint hot enough under the braid to melt. I was pressing down hard enough trying to get an inductor joint to melt (those are always the biggest pain) that I snapped the soldering pencil in half. I wasn't really pressing down that hard... I just think those cheap $15 irons use crap plastic that gets weakened by the heat.

Anyway, do others tin the iron before desoldering or just get a better iron? (I have a bulb-type desoldering iron too, but that doesn't work as well as braid for low, flat joints on tiny inductor leads that are folded right over onto the pad.)

DON73

Thanks for all the suggestions. The iron tip is clean but I can't get it tinned. Even with a clean tip I can't get the wire (from crossover to speaker) hot enough to melt the solder. The Stahl iron is rated at 46 watts I think.
I've done lots of soldering with a large gun style iron and with a torch sweating plumbing joints but this is my first effort at soldering very small wire. I'm using Cardas solder if that makes any difference. I'll just keep trying and maybe I'll get it to work. Thanks for your help.

On3s&Z3r0s

DON73 wrote: »

Thanks for all the suggestions. The iron tip is clean but I can't get it tinned. Even with a clean tip I can't get the wire (from crossover to speaker) hot enough to melt the solder. The Stahl iron is rated at 46 watts I think.
I've done lots of soldering with a large gun style iron and with a torch sweating plumbing joints but this is my first effort at soldering very small wire. I'm using Cardas solder if that makes any difference. I'll just keep trying and maybe I'll get it to work. Thanks for your help.

When you say you can't get the tip tinned do you mean it won't even get hot enough to liquify the solder when you put it directly on the tip of the iron, not touching anything else with the iron? If that's the case then there's gotta be something wrong with the iron.

One other thing to check is whether the tip is well seated in the iron. I would loosen the knurled retaining nut completely, make sure the tip is all the way in as far as it can go, and then crank it down good and tight. Also of course make sure you've got the iron turned all the way up and let it heat up a good 5 minutes before you start soldering with it. If it still doesn't get hot enough to tin the tip then you're gonna need a new iron. The Cardas solder should melt very easily (basically instantaneously) when the iron is at temperature.

Joe08867

Have you tried sanding the tip of the iron? It may get hot but if it has to much resin on the tip it won't tin well or at all.

DON73

THanks Joe and ON3. The irons will all melt the Cardas solder easily but non will stay on the iron tip. I've cleaned the tips of all the irons and I've sanded them with fine grade SP. This morning I needed to remove solder from a Polk mid and after the iron had heated for several minutes I couldn't even melt the solder. I probably need a new iron but since I have three new irons I wanted to get some advice from members experienced with soldering. The Weller has no temp. control but the two Stahls do. I've watched the you tube videos on soldering and I'm doing everything the same way. I'll try a better quality iron but members here have said the Stahl I have will do the job. Thanks for your help.....I do appreciate it.

Joe08867

That is a new one for me. Three irons that won't solder.

Maybe you should try another outlet. Maybe there is already a heavy load on that circuit and the iron isn't getting full power. Might not trip the breaker but could be a dip in power.

DON73

Thanks Joe. I've had them on 3 different outlets in the house and one in the garage. Probably someone here experienced in soldering could pick up one of the irons and solder away with no trouble at all:redface::redface:

On3s&Z3r0s

Stahl rates their cheaper station at 40 watts when it's turned all the way up, but I don't think that's accurate. I have a cheap 30 watt pencil that heats faster and holds heat better. But the Stahls should get hot enough unless there's something wrong with them. Generally speaking, a hotter iron makes for much easier work.

I'd try the tinning again. It's a bit of a delicate art. When tinning, the solder isn't ever going to coat the whole tip (unless I'm doing something wrong, which is possible). When I do it I just quickly touch the solder to top of the uncoated part of the tip, just to get a small bead there. Too much and it could bead up and roll off. Then, put that bead in contact with what you're trying to solder/desolder. It will help transfer the heat. It'll help melt an existing solder joint, which could take several seconds to reach temperature and melt otherwise. And it'll help the solder flow on solder pads or binding posts or whatever else you're trying to put a new joint on. Also, hold the iron as still as you can until the solder melts. If you move it around at all, it'll cool down on you and never melt right.

DON73

I finally soldered the wires from the x overs to the speakers using my pistol grip iron. I've got another iron coming tomorrow and if it doesn't work then it must be me. I have a friend at a local hi fi store and he makes up cables for customers. I'm going down tomorrow and have him give me some pointers. I apologize for being so inept at such a simple skill but you guys are the only ones I know to ask. H9 hasn't let me know yet that soldering is so easy even an idiot could do it:biggrin::biggrin: I'm off to bed! Thanks again.

Tank_PD

I'm curious, which Weller model do you have?

This one was recommend to me by a few EE friends before. Has a temp control.
http://www.amazon.com/Weller-WESD51-Digital-Soldering-Station/dp/B000ARU9PO/ref=wl_it_dp_o?ie=UTF8&coliid=I2YQTQO234PVQR&colid=1M970XZJSTFQF

Joe08867

Maybe the irons have an issue? I hope the pointers help.

dorokusai

Tank_PD wrote: »

I'm curious, which Weller model do you have?

This one was recommend to me by a few EE friends before. Has a temp control.
http://www.amazon.com/Weller-WESD51-Digital-Soldering-Station/dp/B000ARU9PO/ref=wl_it_dp_o?ie=UTF8&coliid=I2YQTQO234PVQR&colid=1M970XZJSTFQF

I use that same series and it works great. You should have a station, not just a pen if you're into work like this.

DON73

SHAZAM! :biggrin: Bought a new Weller ($45) from Amazon and it works. Now soldering is as easy as it looks. I needed to install connectors on wires for four speakers and none of the ones I found fit the speakers connectors. Soldered them all in just a couple of minutes. I just need a much smaller tip for board work. Thanks everyone!

Joe08867

Weller is good stuff. I had a cheapo one from Ratshack that worked but my Weller is awesome. Glad you are up and running.

DON73

One of the ones I have that I couldn't get to work was a Weller. The Weller that I got from Amazon that works is almost identical to the Stahl that I got from Parts Express. Go figure.

dorokusai

Well my station finally gave up the ghost in final crossover upgrade stage, so I was forced to upgrade to a new model. It was an awfully hard choice....hopefully I'll get thru it.

http://www.cooperhandtools.com/brands/cf_files/model_detail.cfm?upc=037103191328

Face

Don't forget to DeoxIT gold the wand connection.

dorokusai

I'm going to use every tweak possible to ensure that the iron heats up quickly and sounds glorious Face. I may even upgrade the internal wiring and capacitors.

pitdogg2

bigger power cord fer sure

zingo

dorokusai wrote: »

I'm going to use every tweak possible to ensure that the iron heats up quickly and sounds glorious Face. I may even upgrade the internal wiring and capacitors.

I think that's smart.

nadams

I need to get myself an ESD safe (or at least grounded) iron. I have a Weller station with a SPG40 iron, and I love it... But, if I get it near a driver, said driver will actually buzz.... Don't like thinking about what stray electrons are flinging themselves off that tip....

inspiredsports

:biggrin:

dorokusai

LOL Inspired...that's a hardcore iron for sure.

zingo

Jer.War

I have heard teachers mentioning that you should always holster an iron which is tinned (has solder on the tip), otherwise the end overheats and tempers. The results is solder does not stick to the end or flow properly. I have not experienced this, as I just did what I was told, but they did have years of industry experience prior to teaching.

audiocr381ve

inspiredsports wrote: »

:biggrin:

You obviously overlooked dampening the chassis with Dynamat. Don't skimp either, it's Dynamat EXTREME.

inspiredsports

audiocr381ve wrote: »

You obviously overlooked dampening the chassis with Dynamat. Don't skimp either, it's Dynamat EXTREME.

If I'd had more time I would have put some Dynamat on top, solid brass isolation cones underneath and some Herbie's dampers on the iron :biggrin: