Desoldering question (Miller XMT welder repair)

Dracula? Rotwang?

Are all desoldering tips (such as 1/8" tips) compatible? I need to buy a few and am a little confused about brand compatibility.

Dunno. Are you having trouble sourcing OEM replacements?

Heh heh - even Pace tips ain't compatible across model ranges. Think they use Microsoft for design work.

I've used both (Pace and Soldapullt) and a Soldapullt would beat the Pace on oinky work. I learned desoldering with a Soldapullt so maybe that is why I could make it work well. I had a Pace desolder-station, two Weller pencils and two 250 watt plus guns at my bench. The Pace required continuous maintenance (as others have said) and it worked well, but a Soldapullt could beat it albeit at a slower rate. I worked on surface mount itsy-bitsy stuff all the way up to... We also had a Hotair station for surface mount chips but that is a whole'nuther discussion...

For Jon, if you are pulling the pencil away from the joint and then moving the Soldapullt in, you are doing it wrong. You leave the pencil on the joint, rest the Soldapullt tip so it touches the board but not the pencil tip and then fire it. Be careful about this, it you contact the pencil tip too much with the Soldapullt you can damage the circuit board trace when it fires.

The mini/small Soldapullt's are crap, (like the model US140 Edsyn Universal Soldapullt) not enough suction. Get the big one like Don linked to. I still have two Soldapullt's, the old Blue and yellow (DS017) and the silver anti-static version (AS196). They are both over 15 years old and still work fine.

Desolder stations on nice to have, but a bit pricey for only occasional use.

Believe me, I know how to use it. I've been using them since, oh,

Oh, I definitely was not suggesting that everyone go out and buy a Pace station. But, Iggy already HAD the station, it just wasn't working right. And, yes, they do take some maintenance, but when doing a bunch of connections, there's nothing that can do it faster. When I use a Soldapullt, I still have to mess with breaking the pins free of the last bit of solder. When I use a Pace, I apply suction while orbiting the desolder tip around the pin, causing the pin to orbit in the PCB hole. This gets the pin/hole cleared of solder much more effectively. This is the technique taught in the Pace manuals, and I can tell you, it is VERY effective. Like these 68-pin connectors in the 6-layer board, when I get the last pin unsoldered, it just falls off the board.

Jon

Ouch, that's real high. If I was wanting to repair the PC board (rather than salvaging the chips) I would stay below 800. I often run it at 750.

If you get good heat transfer at 950 the traces will come off the boards for sure.

Jon

Jon, do you solder with your station also?

How do you use it in reality?

He doesn't do things the right way.

By the way, grinding dust is the reason for conformal coating.

I think that everyone who has used a desolder station for their profession knows the "suck and wiggle" method. I'll stand by my claim though, the Deluxe Soldapullt will beat the desolder station on oinky jobs.

I was the depot solution for our group of shops. I fixed the stuff other tech's bailed out on or badly messed up trying to fix (shrug). I saw my share of circuit board butcher jobs...

Correct. The solder has to be completely melted, and not freezing when you remove it.

The only maintence they could ever need is a new tip and maybe a drop of lube on the o-ring.

I don't do any smd stuff, but I really can't think of any desoldering task task that wasn't doable with just a solder sucker and maybe desoldering braid. The most important thing to have is a decent soldering iron and the correct sized tips. Even cheapo weller irons are perfectly acceptable for most work.

Adding more solder to a joint being undone will almost always help.

To be fair desolder stations were incredibly expensive once and even now secondhand reasonably recent Pace etc still fetch big money. I ended up making my own. ;-)

It is a conformal coating. General Cement in Rockford, Illinois, makes a silicone based version called "Print Koat", as well as the solvent.

Part No. 22-203 - Print Kote Conformal Coating The ultimate coating for PC boards. Provides a protective shield to resist environmental contaminants. Prevents arcing and shorting. Air dry

and

Part No. 22-209- Print Kote Solvent A solvent to remove silicone and other types of protective coatings from PC boards. Required when modifying PC boards or replacing components where the protective coating interferes with the desoldering and resoldering operation.

Allied Electronics stocks it.

Snag is the most reliable solder joint is where there is minimum solder infill.

We use Kester 1544 for hand soldering, and desoldering as well. It's fully activated and works very well. At 50% solids content, it's too thick for a foaming flux bath, but works well in a capillary dispenser for hand work. Maybe you have a Kester distributor there? They produce a large and varied flux line.

I have a one-channel unit at home for desoldering only. I use it rarely, but when I have some large number of connections to desolder, or something expensive that is likely to be a bear with other tools, it is a great tool to have. No matter how difficult the thermal considerations of the board, the Pace WILL desolder the part with no damage, and I get a clean part and a clean board without wrecking the through holes.

I have an MBT station at work that has 3 channels. We got it with a whole pile of tips, handles, etc. I used it for a while for both soldering and desoldering, but am now doing a lot of extreme micro-soldering on chips with 0.5mm lead pitch, and we needed a real micro iron. So, we got a Weller WSL with the WMP micro-pencil, which is actually a darn good general iron for all electronic work.

I have a collection of older Weller digital readout soldering stations at home with the 1302 mini soldering pencil, which I actually like just a little better than the WMP. You can get an EC2002 and ESD1302 pencil fairly cheap on eBay if you are patient.

Jon

Interesting. My regular $3 soldering iron is fine for wires, but too large for circuit boards. I will indeed look into soldering stations and will check out my station thoroughly to see what soldering possibilities it offers.

"Bob La Londe" wrote in news:47a015a0$0$26111 $ snipped-for-privacy@free.teranews.com:

Ghetto desoldering:

Heat up the solder and rap the board, usually edgewise, against the bench.

Works quite well but not recommended unless wearing lots of protection.