Unleaded

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boots
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Unleaded

Post by boots »

Do you guys have any advice on how to work with the new lead-free solder?

I have agreed to do some repairs for a couple local shops, and all they seem to feed me are broken Peaveys. Ugh. I've been having a hard time desoldering and removing components from the PCBs, and just a hard time getting the solder to melt and flow, in general. I suspect it is the new green, unleaded solder.

Is there a special flux or something I should know about?

I have had some luck by adding a little "real" solder to the joints and going from there.

So far, I think I hate working on broken Peavey stuff. It's a PITA and definitely not much of a money-maker.
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Structo
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Re: Unleaded

Post by Structo »

I have a Crate Palomino combo.

I was having some oscillation problems with it and decided to re-flow some solder joints.

First time I have run into lead free solder.

Hopefully it will be the last time....
Dry, crumbly crap.

What I should have done was use a vacuum solder sucker to remove the nasty lead free solder before I attempted to use the lead solder.
Tom

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xtian
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Re: Unleaded

Post by xtian »

I don't know much about it, except that no-lead solder requires higher temp to melt.
I build and repair tube amps. http://amps.monkeymatic.com
vibratoking
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Re: Unleaded

Post by vibratoking »

I feel your pain. Wetting it with leaded solder certainly helps. There are other issues as well. A quick google returned this:
http://www.kester.com/kester-content/up ... .19.06.pdf
Electronic equipment is designed using facts and mathematics, not opinion and dogma.
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Leo_Gnardo
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Re: Unleaded

Post by Leo_Gnardo »

I remove what I can with solder wick. If it takes some leaded solder to accomplish, so be it. Then resolder the connection with something you know works.
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Ken Moon
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Re: Unleaded

Post by Ken Moon »

I am a big user of liquid flux. I buy it by the gallon.

I've had success removing lead-free solder using liquid flux, Q-tips and wicking braid.

I use a 750 degree tip, put a dab of liquid flux on the joint and another on the wicking braid, drag the wicking wire across the joint slowly, applying the iron to the top and pressing the iron down onto the joint.

Flip the Q-tip around and dab of the mess of flux. Then re-solder the joint using regular solder.

You may have to do this twice.
DonMoose
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Re: Unleaded

Post by DonMoose »

Ken Moon wrote:I am a big user of liquid flux. I buy it by the gallon.

I've had success removing lead-free solder using liquid flux, Q-tips and wicking braid.

I use a 750 degree tip, put a dab of liquid flux on the joint and another on the wicking braid, drag the wicking wire across the joint slowly, applying the iron to the top and pressing the iron down onto the joint.

Flip the Q-tip around and dab of the mess of flux. Then re-solder the joint using regular solder.

You may have to do this twice.
Then clean up the flux - otherwise it will absorb moisture. That will be followed by growth of tin whiskers and/or dendrites that eventually become short circuits.
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Phil_S
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Re: Unleaded

Post by Phil_S »

I seem to be the lone silver solder user here. As I've noted, I am an amatuer, so I often go months without heating up the iron. Much has been said that is right. I'm going the dismiss some of this as simple crustiness from being spoiled by the leaded.

Mostly, I find that a well conditioned tip is key to transferring enough heat. If the tip isn't shiny, it won't transfer enough heat. I often find when the tip has been sitting for weeks or months without use that it has a layer of nasty, crusty oxidation that needs to be removed. I'll spend some time running it over a wettiish-damp sponge to make enough steam to get the layer of oxidation off it. Then it needs regular wiping on the sponge to keep it shiny, along with tinning the tip. Flux will help but is not always essential. Keeping the iron hot enough is important, as well. I use a sold-a-pult to desolder. As soon as the solder wets, apply the vacuum to it.

Be patient. Silver takes longer to wet but once you get it going, it is like any other solder.
boots
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Re: Unleaded

Post by boots »

The biggest frustration is desoldering, in order to remove components and break the circuit for troubleshooting. It becomes such a time consuming hassle to break the circuit, that I lose my troubleshooting momentum!

Breaking the circuit to isolate problems is much more quickly and easily done in tube amps! And it seemed much easier on PCB's too, back in the days when the solder was easier to work with.

Does anybody know where to buy liquid flux? I used to be a big fan of it when I worked in a repair facility in the 90's. I would like to be able to score a gallon of it. Everything's better when wet!
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Structo
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Re: Unleaded

Post by Structo »

I have a bottle of flux here.
MG Chemicals Rosin Flux.

I bought it at Fry's.

http://www.amazon.com/MG-Chemicals-Corr ... B005DNR01Q
Tom

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Ken Moon
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Re: Unleaded

Post by Ken Moon »

Looks like the stuff. They also have flux pens, but I never got the hang of those.

Fry's is cool - they carry stuff like shrink tubing that is impossible to find anywhere else.

I do prefer a dry tip cleaner to a wet sponge:

http://www.amazon.com/Hakko-599B-02-Sol ... XJX3X6Q43B

I also use anti-wicking tweezers, dental tools and a variety of clip-on heat sinks when soldering, but I won't bore you with the details - there are a bunch of mil-specs like MIL-STD-2000 that have all the details, and you can choose how far you want to go for yourself.
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Phil_S
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Re: Unleaded

Post by Phil_S »

Ken Moon wrote:I do prefer a dry tip cleaner to a wet sponge:

http://www.amazon.com/Hakko-599B-02-Sol ... XJX3X6Q43B
Nice. I didn't know what it was called or where to get one. I gave up! Thanks. Now I just need another $25 worth so I can get free shipping!
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