Soldering Tips

Discussion in 'Hardware, Setup & Repair [BG]' started by td1368, Mar 22, 2001.

  1. td1368


    Jan 9, 2001
    Does anyone have any tips for soldering in new pickups. I'm puting in Dimarzio Ultra Jazz pickups into my Fender MIJ bass. The pickups are direct replacements so I just need to unsolder the old and put in new. Just wondering if anyone has had any experience that could help. Thanks
  2. Soldering is a skill like any other in that you need to understand the process and then practice to do it well.

    The number one rule is: Heat your work, NOT your solder!

    My number two rule is: Use flux in addition to flux core solder for better flow.

    My number three rule is: Tin your leads!

    The first rule is accomplished by trapping your work between your iron and the solder so that the work heats quickly and the solder melts into the openings. Of course, there are situations that you can't do this but that is a basic method.

    For the second rule use paste style flux and coat the raw metal components before heating. The flux helps clean the metal and acts like a surfectant to aid in flow.

    The third rule really helps when soldering 2 bare wires. Tinning means to seal the end of the wire in solder before the leads are twisted together. When you heat the leads the solder that is already in the wire will melt together, sometimes eliminating the need to add any solder at all.

    I might at another rule here: Use an iron with at least 50 watts of heating power. The smaller pencil irons work for very small work but the Weller guns are the best for putting the right amount of heat into the work QUICKLY. This means that there are fewer cases of melted insulation and damaged components.

    A "cold" solder joint is one that appears to be sound but doesn't transmit the current as required. I have found that most "cold" joints show a similiar characteristic of being very dull in appearance while the good ones are usually bright and shiny. This may not actually be the case but it seems like it to me.

    Hope this helps!
  3. also...if you can't get the iron to sit with enough surface area on the piece, you can build a "solder bridge" that will allow it to heat faster.
  4. notduane


    Nov 24, 2000
    Good stuff Mr. H! :D
    A cheapie DMM might also save some grief...Set it on the LOWEST Ω's range
    and do a continuity check. Readings should be less than 1 Ω (usu MUCH less).
    Anything higher, and you probably got a "cold" joint.

    Solder "bridge" ?...I always thought it was s'pose to be a good
    Electrical and Mechanical connection.
  5. td1368


    Jan 9, 2001
    Thanks for the tips.

    I also did a web search for "soldering tips" and found some good info on electronic soldering for circuit boards and things like that. One of the best was this link:

    They recommended a 30 w soldering iron but that was for transistors and stuff. I'll take your advice Hambone and get an iron with more capacity.

    The url seemed a little funny so I checked it. It's just a ham radio page.
  6. Christopher


    Apr 28, 2000
    New York, NY
    Safety tip:

    Do your soldering in a well-ventilated environment.
  7. Just wanted to weigh in on getting a good iron. I picked up a cheapo pencil iron and it literally lasted for one connection. I had to run out to Home Despot and get a 75 watt Weller that's just fantastic - about 27 dollars. The small extra expense will save you time and frustration.

    Check out:
    for good step by step installation instruction.
  8. pkr2


    Apr 28, 2000
    coastal N.C.
    The solder bridge in Hambones tip is a good thing. The faster the solder joint gets up to temp the less destructive the heat is to things like printed circuits and insulation on the wires. The solder bridge provider a high heat conductivity path from the iron to the solder joint. The bridge Hambone describes doesn't replace a mechanical joint. it just enhances it.

    The "bad" solder bridge that you see mentioned in the textbooks means a bridge of solder that accidentally shorts two adjacent solder points or conductors together. Not a good thing.

    Some good tips in this thread but I'll add one that can make the difference in a good job and a bad one. Make SURE that any electical soldering is done with rosin core (flux) solder. Acid core solders beautifully but the acid begins to corrode the joint immediately and the joint will almost always fail later on.

    Same holds true for those little flat cans of soldering paste. Dont use that stuff for electrical work. It will corrode the connection.

    Finally, a good magnifying glass can be just as important as a good iron. Unless you have eyes like an eagle, there can be problems with a solder joint that can be very hard to see with the naked eye such as stray wire whiskers, cold jpints and joints that moved before the solder completely hardens.

    A smooth, shiny surface on the solder joint is a good indication that the joint is sound. A frosted look to the joint always indicates a joint that can cause trouble.

    The old adage About heat the joint untill its hot enough to melt the solder and then apply the solder looks good on paper but that procedure will ALWAYS destroy a printed circuit board.

  9. My additions to this:

    Make sure your wires or leads will stay where you want them without you holding them in place. If you have to hold them while the solder cools, it makes a bad joint. It may look like your hand is still, but it ain't on a microscopic level. Pre-bend the wires or set a screwdriver on top of the wire to hold it where you want it.

    Tin the iron, touch it to the joint spot, feed in the thin rosin-core solder making sure it flows like water and "soaks" into and around what you are soldering, remove the iron. Don't blow on it, this weakens the joint as well.

    Practice makes perfect.

    Get yourself a Weller WP30 or equivalent.

    They do make Rosin flux in little tins, but I can't find it anywhere-I've used Marlin brand at work before when I was a tech. The tins at hardware stores are Acid flux and should be avoided as stated above. That acid stuff is for plumbing.

  10. pkr2


    Apr 28, 2000
    coastal N.C.
    "Get yourself a Weller WP30 or equivalent"

    Agreed. Buy one and you don't have to buy another one. You can actually buy repair parts for a weller that don't cost as much as a new iron.

    Another benefit is that a weller is usually a grounded tip iron. Some of the stuff used now in a lot of gear has static sensitive parts that just touching an ungrounded iron to can destroy.