Deang Posted July 27, 2002 Share Posted July 27, 2002 I've been reading some online tuturials and practicing my soldering tonight. One thing I am not clear on is solder types. When I spoke Dennis Had on the telephone, he told me NOT to use any solder with lead in it. The only thing I could find at Radio Shack without lead was some solder that is 96% tin and 4% silver. So, now I've been reading about melting points of various types of solder and what not. I also found some pictures of proper and improper P.C.B. joints. I took the bottom plate off of the AE-3 off tonight and re-examined my joints. It appears I may have left the heat on too long, and probably used a little more solder than I needed. I have several questions. What is the proper solder type for audio connections? When I de-solder, there is solder on the wire. Can the wire be re-soldered directly, or should one clip the leads? More times than not I'm finding there is not enough wire to afford me the luxury of clipping away. All of the tuturials have contradictory information regarding the amount of solder to use on a joint. I've read everything from "a few milimeters" (which I find ridiculous unless the solder has the circumference of a garden hose), to an inch or so. How does one know "when to quit" feeding the solder? What should I be looking for that tells me to "stop". I can only get the shiny appearance about 1/2 the time. Usually I have to reheat the joint to get it to look right -- and then I get the teardrop effect. I just learned this means heat as been applied for too long. Of course, none of the material I'm reading tells me if this is "bad". I know the joint is not moving because I tape the wire to stop it from moving. I apply the heat, wait a few seconds, then feed the solder from the other side of the joint. It runs in, I feed about an inch of solder in, then pull away. The solder immediately begins cooling, and then the very top of the bead turns a little grey while the rest of the joint is silver. I can't for the life of me figure out what I'm doing wrong. I'm trying to figure out the "rosin" and "flux" thing. Should flux always be employed? Does all solder, regardles of "type", contain rosin? Opinions? Quote Link to comment Share on other sites More sharing options...
Malcolm Posted July 27, 2002 Share Posted July 27, 2002 IMHO 63/37 lead/tin solder is fine for all audio and most other electronic uses. And you definitely want to stick to something like it for PCBs. The other alloys generally have a higher melting point making it more likely you will lift a pad or trace. OTOH solder is like speaker cable. Everyone in audio seems to have his own preference. And there is a lot of questionable folklore out there on the subject. You can resolder without clipping leads. What you have, in effect, is a tinned lead, which makes soldering easier. The solder you apply to the connection will bond to a tinned part easier than to bare copper. The right amount of solder is the minimum necessary for a good electrical connection. Do not try to get a good mechanical connection by using a lot of solder. Create a good mechanical connection first, then solder. It is easier to show someone a good solder joint than describe one. But, if you are soldering a wire to a pad on a PCB, the solder will flow down the sides of the lead, level out on the pad, and flow to the edges of the pad, but not beyond. If the lead is straight through, the solder will look a bit like a volcano with the lead coming out the middle. If the lead is flat, the solder will look a bit like a mountain range. Shiny is important. Otherwise you probably have a cold solder joint. This is usually a result of not using enough heat or moving the connected parts before the solder solidifies. From what you describe, it may also have something to do with too much solder. I think the teardrop effect you see is a result of too much solder and/or not enough heat. I have never seen a bad joint result from too much heat. What heat can cause, however is lifting of pads or traces from a PCB, or damage to the part being soldered. A heat sink applied between the joint and the body of the part can help prevent damage to the part. Not much you can do about the PCB but get in and out with the soldering iron as fast as possible. Flux prepares the metal by removing oxidation so the solder can bond well to it. Rosin based fluxes are used in electronics. Acid based fluxes are used for solder pipes, etc. Do not use acid fluxes for electronics. If your soldering iron is hot enough, you should be able to melt solder almost immediately after applying the iron to the work. Temperature controlled soldering stations are best, but expensive. If you are using less than a 40 watt iron, I think you will have trouble. More parts are damaged by using too low a wattage iron than by using one bigger than necessary. There is more time for the heat to flow into and damage the PCB or part while waiting for the joint to heat enough to melt the solder. I find that chisel shaped tips work best for me. Remember to keep the tip clean for effective heat transfer (wipe it on a wet sponge before soldering to get the rosin residue off). FWIW practice, practice, practice! This is a skill where practice will make perfect. Of course, you might want to practice on something you don't mind destroying. Quote Link to comment Share on other sites More sharing options...
Deang Posted July 27, 2002 Author Share Posted July 27, 2002 Can I flux the tops of my questionable joints with a pen and then go back over them with the iron? Or do you think it better that I desolder, clean the PCB and resolder? I was "told" a 15 watt iron would be enough. I guess it would have been if I'd used a lead based solder. I've been practicing on an old PCB and bare copper wire. I just learned about soldering pots to make tinning the leads easier. I think the reason my joints held up was because I hung a drop of solder off of the tip of the iron before I applied the iron to the joint. I didn't have any problem getting the solder to flow, and all appeared normal until I removed the iron. I talked to several people who solder without flux, as they said there is already flux in the solder itself. Isn't it possible if I left the iron on the joint too long, that the flux might burn away and leave me with a dry joint, as opposed to a cold solder joint? Quote Link to comment Share on other sites More sharing options...
lynnm Posted July 27, 2002 Share Posted July 27, 2002 Disclaimers: 1.)Malcolm's post is damned near to being a 4 paragraph textbook on soldering.My comments are supplemental: 2.) Dennis Had is one hell of a designer of Audiophile grade amps so when I imply below that he is full of schieze my criticism is limited solely to the comments he is alleged to have made re soldering technique. With all due respect to Dennis Had the notion that one should use solder with no lead content is utter BS. Silver has a high melting point and requires a high wattage iron to be properly worked. It is true that the temps needed for "silver soldering" are not especially dangerous to tube equipment but those same temperatures are hazardous to any solid state devices being soldered. Silver soldering is not for the novice and in any event the "benefits" are not,(IMHO), significant. quote: I was "told" a 15 watt iron would be enough. I guess it would have been if I'd used a lead based solder. A 15 watt iron is sufficient if one is using a 50/50 tin/lead solder and knows what the hello they are doing. A 15 watt iron is essentially useless when one is attempting to use so called silver solder. A 25-50 watt iron is more useful for most users as frankly they deliver sufficient heat to effectively heat the joint without the likelihood of overheating if applied judiciously. quote: I think the reason my joints held up was because I hung a drop of solder off of the tip of the iron before I applied the iron to the joint. I didn't have any problem getting the solder to flow, and all appeared normal until I removed the iron. c> Using a drop of solder to glue parts together is a recipe for trouble. As Malcolm has stated the only viable way to create a proper solder joint is to first make a solid mechanical connection of the parts in question and then heat those parts to the point that the solder will melt on contact with them. The parts should be heated to the point that the solder will flow onto and around them. Using excess solder and/or heat is not only wasteful but actually increases the risk of a cold solder joint and/or unintended shorting of a connection to some other contact. A word of explanation about "cold" solder joints: This term has been generalised to cover any and all causes of a poorly soldered joint. A "cold" solder joint is characterised by having a dull surface and may also feature visible cracks in the joint. I have seen that condition described as appearing granular. Aside from being ugly this type of solder joint is undesirable because it will be mechanically unsound and also offers a significantly higher resistance to current flow than a proper solder joint. Generally "cold" solder joints are the result of the application of insufficient heat to a joint being soldered and/or movement of the parts being soldered before the molten solder has had sufficient opportunity to solidify. quote: I talked to several people who solder without flux, as they said there is already flux in the solder itself. There are two broad categories of soldering flux: 1.)Acid paste - This used in plumbing applications and should NEVER be used in electronic applications as it will cause corrosion and contact failure. In addition the acid can actually leach out of the area being soldered and eat through the traces of printed circuit boards. 2.)Resin This is the type generally used in electronic work. It comes in one of two forms. It may sometimes be supplied as a paste for use with solid solder wire. Ordinarily solder that is supplied as solid core is intended for plumbing or sheet metal work and has a higher melting point than is suitable for electronics work. More commonly however electronic solder is supplied as "resin core" which simply means that the solder consists of a thin tin/lead or tin/silver tube filled with resin which permits the user to supply both the solder and the flux to the joint simultaneously. I hope I have not materially added to the confusion around this matter. This message has been edited by lynnm on 07-27-2002 at 06:09 PM Quote Link to comment Share on other sites More sharing options...
NOSValves Posted July 27, 2002 Share Posted July 27, 2002 Deang Here's what you want to get this stuff Rocks. MDeneen turned me onto it and I've never looked back Kester "44" Rosin Core Cat # 24-6337-0027 This stuff really works nice better than anything you will get at Radshack that's for sure. Craig ------------------ HH Scott 299 Amp HH Scott LT-110B Tuner HH Scott P-87 Turn Table JVC JL-F50 Turn Table Sony CDP-CA7ES CD Drive 1985 Walnut Heresey I W/Layne Audio Woofers KSW-15 Subs>c> Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted July 27, 2002 Share Posted July 27, 2002 DIYCable sells the Kester "44" as well. I talked about the various thicknesses and the lead content in a previous post. I know why Dennis said "NO LEAD" but I really dont think it necessary for him to say this. Other have talked about solder in this thread; what I WANT TO STRESS is for you NOT to solder that AE-3 DJH preamp until you have REALLY practiced on some connections within junk or your wife's clock radio etc! It seems you moved to the "heavy" stuff pretty damn fast. Indeed, it takes a bit of practice to get a good joint and I sure would be leary of moving into the realm of my $1500 preamp at this stage, at least until you have some serious practice on some joints that dont matter. Making a mistake on the AE-3 could lead to a hefty bill from AES if you toast something. I think it's great you are tackling this, but remember to use good judgment. Learning on your main gear is a risky affair, especially a tight area device like the AE-3. kh ------------------ Phono Linn Sondek LP-12 Valhalla / Linn Basic Plus / Sumiko Blue Point CD Player Rega Planet Preamp Cary Audio SLP-70 w/Phono Modified Amplifier Welborne Labs 2A3 Moondog Monoblocks Cable DIYCable Superlative / Twisted Cross Connect Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover Links system one online / alternate components / Asylum Listing f>s> Quote Link to comment Share on other sites More sharing options...
Randy Bey Posted July 27, 2002 Share Posted July 27, 2002 For what it's worth, I've been using Rat Shack silver solder for years. Someone will now tell me that their silver solder is better than the Rat Shack stuff and that is why my hifi sounds like crap. To each his own. I would agree that a hot iron (45 watt) is preferable over the more common 25 watt irons. Get a roll of solder wick and a decent 'solder sucker' and you're all set to learn. Find a junk radio or VCR or whatever you might have gathering dust in the back closet and go to town. When the whole thing is atwinkle with shiny solder spots you will be ready grasshopper. Quote Link to comment Share on other sites More sharing options...
Deang Posted July 27, 2002 Author Share Posted July 27, 2002 Thank you very much guys. Great posts by everyone. I had read several online soldering tuturials before I started. I also practiced on the old PCB for about 45 minutes before I started. I didn't really use the solder as "glue" to connect the lead to the land. Once the leads went through the holes, I ever so slightly splayed each one. I didn't want to press them flush against the PCB, because I knew there might be the possibility of having to redo them. I wanted to make sure I could get them out with relative ease. When I said I used a "drop of solder" on the end of the iron before I made the connection -- it wasn't so I could "paint" the joint to make the mechanical connection, but simply to aid in the transference of heat. Using this method I was able to get the solder to flow around the joint after about 5 or 6 seconds. I have not yet had my digital camera returned to me. I will get it on Monday. What I will do is take some pictures of my "handi-work" and post them here for evaluation. If you all say "nay", I will start over. I would probably order another PCB from Cary (only $1.50), so I can start with a clean board. I agree that the AE-3 is a pretty pricey item to developing my skills on. However, it did look relatively easy. Of course, most things usually do look easy to me until I actually put my hands into them! Will I be able to you the Kester for soldering my new caps onto the crossover boards of the DQ-10's? I'll put my order in for the Kester today. Randy -- braid sucks! I was practicing with that stuff last night and the only way it would work was if I left the iron on the braid for 20 or 30 seconds. Too long!! Think I just need a higher wattage iron? This message has been edited by deang on 07-27-2002 at 09:43 AM Quote Link to comment Share on other sites More sharing options...
NOSValves Posted July 27, 2002 Share Posted July 27, 2002 deang Actual the soldering your doing is harder than what I do working with pcb's is alot less forgiving of overheat and damaging the board. I use the same technic as you and keep some solder on the end of my tip to help it heat quick it really helps. I found doing Tim's EICO caps a few month's ago that the caps he had (can't remember the brand but they were $6 to $8 each) but they had stranded leads and really easy to melt wire sleeves. I was really not impressed with the construction at all. I would much rather have a solid lead without any wrap if the wrap is going to be junk and stranded leads are just a pain in the A$$ !!! Craig Quote Link to comment Share on other sites More sharing options...
lynnm Posted July 27, 2002 Share Posted July 27, 2002 I agree with Kelly when he says that you should be learning how to solder on something less valuable than your $1500.00 preamp. For crying out loud practice a few dozen joints on some junktiques before assaulting your audio equipment. That said if you insist on doing so: quote: I think the reason my joints held up was because I hung a drop of solder off of the tip of the iron before I applied the iron to the joint. I didn't have any problem getting the solder to flow, and all appeared normal until I removed the iron. I think you miss my point when you state that you are not "glueing" the joint but are in a sense using the molten solder to preheat the joint - You are positively begging for poor solder joints by doing that. Proper technique requires that the soldering iron tip have a small and evenly distributed amount of solder on the tip -literally nothing more than a coating of solder. Ideally the components being soldered should also be tinned before being mechanically joined. The "tinned" soldering iron tip should then be applied to the existing mechanically solid joint and the parts heated for a few seconds. The iron should remain in contact with the parts while the solder is applied to the pieces being soldered,(not to the iron tip). If the temperature is sufficient the solder will become molten on contact with the heated joint and flow into and around the joint. At that point remove the solder wire from the joint and THEN remove the iron's tip from the joint. Allow the solder to harden up without allowing any motion of the parts being joined and allow the joint to cool naturally ie. do not blow on the joint or fan it etc. Artificially accelerating the cooling process drastically increases the odds of a poor joint and saves perhaps a second or two of time. Compare that second or two savings against the several minutes of dissassembly/reassembly and potential for damage resulting from the need to resolder. In addition a cold solder joint which is not immediately visually obvious - poor joints can look picture perfect - can cost many hours of troubleshooting or worse can cause you to be spend months or years listening to a device that sounds "OK" but which has the capability of sounding exceptional. Trust me one does not learn to solder from reading tutorials - Even mine 8~)>. Reading is the smallest part of the learning task. Application of the skills described and the achievement of consistency in results is the only true route to becoming competent in soldering. Quote Link to comment Share on other sites More sharing options...
Deang Posted July 27, 2002 Author Share Posted July 27, 2002 Understood. No more touchy on the AE-3 until I know what I'm doing. Thanks! Quote Link to comment Share on other sites More sharing options...
Weiming Posted July 27, 2002 Share Posted July 27, 2002 Just some personal observations and experience here. I have never been able to get a shiny finish if I use eutectic 63/37 solder. However, it is easier to work with as the melting temp. is lower. Silver-based solder requires a higher wattage iron and the worst to use are those lead-free kind unless you have a soldering station like a Hakko, Goot or Weller. Oh ya, if the solder has a flux resin core, then there is no need to use additional flux to condition the joint to be made. Just make sure the surfaces are clean. Another thing is to remove the excess flux after soldering by cleaning the job using a cotton bud dipped in IPA. ------------------ Solstice Quote Link to comment Share on other sites More sharing options...
Deang Posted July 27, 2002 Author Share Posted July 27, 2002 What is IPA? Quote Link to comment Share on other sites More sharing options...
mike stehr Posted July 27, 2002 Share Posted July 27, 2002 Damn! I think Lynnm gave you about the best soldering advice you could ever get Dean! I think IPA is some sort of alchohol. Soldering is a practice makes perfect kind of thing. This message has been edited by mike stehr on 07-27-2002 at 11:56 PM Quote Link to comment Share on other sites More sharing options...
WMcD Posted July 28, 2002 Share Posted July 28, 2002 I built dozens of Heathkits as a young lad. The first were not so pretty in the solder end, but worked. Later, the art of routing wires and getting the heat transfer right became an art which I mastered. Now, decades later, I have to relearn it again. One issue, for me, is to keep a thin coat of solder on the tip of the iron, i.e. that it is "tinned". The tip of the 'iron' is actually copper. I think things get out of wack when the tip gets too hot and the solder there oxidizes. Further, the copper gets grungy. One low level solution is to wipe the tip (while hot) on a wet paper towel. That gets off the oxidized solder and you apply a bit more. If the tip is in bad shape you can wipe it with 400 grade wet or dry emory paper from 3-M, from HD. Essentially, things work best when the iron has a shiny tip. I should get a temperature regulated iron. In my experience: We're dealing with a piece of wire and a solder lug or a piece of wire and a p.c.b. trace. It is best to place the chisel tip of the iron at the intersection of the two. There is some heat transfer by contact, but not quite as quick as I like. The solution is to feed the solder into that intersection. The iron melts it and then the heat transfer is increased. Then the components heat up and wick up solder. It all happens in a second. Then you have to remove the iron before the components overheat. I prefer the thinner solder mostly because you can get it into the joint. I agree with the thought that you need a mechanical connection first. But this is just a matter of splaying the wire through the hole or crimping around the terminal. The real point of it is to prevent the wire from moving when you take the iron away and the joint is cooling. There is also a problem with diagnosis of what is wrong with a joint. If it hasn't been heated enough or there has been movement, it looks grainy. On the other hand, a joint that is overheated looks dull from oxidation. So it takes some experience to understand whether you're dealing with too much or too little heat. I fully agree with the use of a solder sucker to clean things out of an old joint, or a new one which doesnt look right. I've used the wicking with a bit less satisfaction. Gil This message has been edited by William F. Gil McDermott on 07-28-2002 at 05:51 AM Quote Link to comment Share on other sites More sharing options...
NOSValves Posted July 28, 2002 Share Posted July 28, 2002 Almost forgot to add that Radshack sells this small tin can of tip tinning stuff (Can't remember what they called it exactly) it has a adhesive strip on the bottom to mount it to your soldering station. Its great for cleaning and tinning your Tip. Its cheap too !! Craig Quote Link to comment Share on other sites More sharing options...
lynnm Posted July 28, 2002 Share Posted July 28, 2002 IPA=Isopropyl Alcohol ?? I thought Weiming was talking about India Pale Ale! - No wonder my Power Amp smells odd! P.S. Weiming I took a look at the pictures of your system - Nice Work! This message has been edited by lynnm on 07-28-2002 at 01:19 PM Quote Link to comment Share on other sites More sharing options...
Weiming Posted July 29, 2002 Share Posted July 29, 2002 Yea, I meant Isopropyl Alcohol. Useful stuff for cleaning solder joints and vinyl Thanks for the compliment. It actually took me more time to procure the hardware, drill the required holes and finish the chassis than to actually solder it. Now my next step is to do some cap swapping with the new Audio Note PIO. quote: Originally posted by lynnm: IPA=Isopropyl Alcohol ?? I thought Weiming was talking about India Pale Ale! - No wonder my Power Amp smells odd! P.S. Weiming I took a look at the pictures of your system - Nice Work! ------------------ Solstice Quote Link to comment Share on other sites More sharing options...
meagain Posted July 7, 2007 Share Posted July 7, 2007 Yes, I'm bumping a thread from 2002..... I have to resolder a broken area to jacks on a piece of gear (OK, husband project).... It has silver wire. I was advised to use TRT Wonder Solder. I can't seem to find what properties this stuff has but maybe Radio Shack has the same stuff. They have: 1) Lead-free solder 96% tin/4% silver. 2) Rosin core silver bearing solder 62/36/2% tin/lead/silver Shall I assume the lead-free to be better with using silver wire that's attached to gold port thingies? And, would there be anything special in the way of prep for this? Here's a pic there's a tiny red wire that's broken off the prong thing at the rca jack. Quote Link to comment Share on other sites More sharing options...
mike stehr Posted July 7, 2007 Share Posted July 7, 2007 "Rosin core silver bearing solder 62/36/2% tin/lead/silver" It's what I use. I have no problems with it. Yeah, it has lead in it. Just run a fan nearby so you don't inhale too many fumes. Take quick breaks, get some air... You'll have to re-strip that red wire, and then somehow suck the solder out of the tube on the end of that RCA jack. Either with a solder sucker or solder wick. Solder wick would probably be best for that application. The piece of broken wire is more than likely still in the end of the jack. Once the end of the jack is free of wire and solder, you can re-insert the wire and solder it back up. And you'll have a good connection. Find some junk electronics to practice on first. Quote Link to comment Share on other sites More sharing options...
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