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Ordered 6 Mundorf capacitors from Roy to put in my VTA PH16, should be here any day. I built the phono stage myself but my skills at de-soldering are lousy at best, I hate doing it. Any advice on putting these things in? Also, why does solder you accidentally put in a wrong location not F$#%@! melt no matter what you do to it? :-(
Follow Ups:
I second what John wrote about a soldering station. Those devices maintain a constant controlled temperature. From what you say about difficulty in removing old solder, I am guessing you're using a weak iron with no temperature control. Both the Weller that John uses and my Haake cost a bit over $100, will last forever and make jobs like this easy. I also have both a cheap spring loaded solder sucker and braid, and the sucker does it for me 95% of the time.
One hint: when removing radial-lead electrolytics, don't try to pull both leads at the same time if you want to save the cap for future re-use. Heat one lead and pull gently. Then heat the other lead and do likewise. Back and forth until the cap is free. This will also preserve the circuit board tracings, so you don't destroy what you were trying to upgrade.
In fact i have to crank the thing up so darn high for the lead-free solder I used originally. I'm going back to lead
Edits: 01/14/21
My Haake came with a default to 750 degrees, and that's where I found it works very well, with lead-containing solder only. So far, I have been able to avoid lead-free solder. Before purchasing the Haake, I had been using a Velleman solder station for maybe 15-20 years, which I used to set at about 670 degrees. The higher temp of the Haake works much better.
I'm around 400 F , as low as I can and have the solder still melt. I was about 575 for the lead free. I'm going to go higher now, no wonder I was having issues. I have a couple different solders now that have left their packages since my original build and now I forgot which one is lead or lead-free. :-(
at higher temperatures of the solder gun, you can get in and out much faster with actually less risk of overheating and damaging a part. The change from ~670 degrees with my Velleman to 750 degrees with may Hakko shows me this is true on a daily basis. I just love that Hakko, even though I misspelled the brand name several times above. I bought the 888D for a bit more than $100; it's all I will ever need.
wish I knew this before I built the PH16, would have saved me some grief and profanity ... lesson learned. I do have variable temp, some off brand cheapo called X-tronic, but seems to work ok. I don't think that beats the rack stereo I once saw called "Electro Brand", with a 'tower' speaker containing maybe one 5 1/4 driver.
If you are working with a ground plane or heavy traces, which is pretty common with caps, a higher wattage soldering iron is helpful. Working fast might be necessary due to the high heat to ensure you don't damage the PCB.
More POWER!! :) Definitely dating myself.
Mike
nt
I've never had as much luck with using just solder wick as some others here, but IME that tool right there is the real deal, especially with point-to-point gear. If you're working on unusually heavy solder joints/blobs, a second low-power iron helps to loosen it for easy removal. I have a Hakko desoldering kit, which of course is badass, etc, but it also requires more maintenance to keep the performance up to snuff, and it's a still a bit bulky to use in the aforementioned point-to-point gear, which can be both tiny and cramped.
If you do buy one of the vintage style desoldering tools, get extra tips and stock up on steel paper clips to keep the nozzles clear (it stays hot enough that you can *carefully* run the clip in the nozzle to make sure it stays clear).
I have not had a reason to use it yet. Thanks for the paper clip tip too.
desoldering wick works well enough that the cap will drop out by itself.
The problem is not that there is evil in the world, the problem is that there is good. Because otherwise, who would care?
Like I said, the wick has never been great for me (in over 40 years of trying), although I have had some success using it to fine tune some desoldered areas.
shoot me an email, and I'll send you mine.
The problem is not that there is evil in the world, the problem is that there is good. Because otherwise, who would care?
Other brands just aren't the same and are frustrating to use.
Both the Cat-A-Pult and my current electric I linked to down the thread are great for point-to-point but often leave solder in a PCB eyelet. Heating the lead on the new part and trying to push it through is hit or miss and can overheat the part.
Holding the braid with the iron to the eyelet and then introducing a bit of fresh solder just as if you were soldering the braid to the board, then pulling/rubbing an inch or two of the braid along instantly clears the hole. I'd need prehensile toes to do that with a bulb type.
As others have posted, a solder station is desirable; my Hakko is nearly old enough to vote and invaluable especially when you need to bring the thunder like tinning heavy solid core wire for ground buss or tinning that pesky Cardas with each strand urethaned.
With great power comes great responsibility, though; especially beginners should be careful and stay in the 700 degree range for nearly all tasks. Using the higher heat to quickly get on and off which is preferred, takes some practice.
Any Damned Fool Knows One Horse Can Run Faster Than Another
geze maybe that's my problem, I'm working just over 400, except with my lead-free solder. I was afraid over overheating stuff.
I have a Hakko also and do pretty much everything at 700F. I occasionally go higher for heavy duty stuff but rarely ever go lower. At that temp the solder melts pretty much instantly and you can get "in and out" quickly and not overheat the part. Soaking a part at 400F. for long periods will cause overheating.
.
Freak out...Far out...In out....
Any Damned Fool Knows One Horse Can Run Faster Than Another
Nt
nt
Nt
nt
Agree, generally, the wick is preferable to the suckers as they one, will clog up, and two, may or may not suck out all the solder. What I do is use the wick to get the most of the old solder up, then use the sucker to finish up any through hole mounting pads if need be.When inserting the part, a radial cap for instance, I push it all the way down onto the board itself, then flip the board, holding the cap in place and gently bend the leads to hold it in place, then begin to solder.
Make certain your have freshly tinned your tip, use high enough heat to form a good solder and either wet the area with a flux pen or use rosin core solder as you want to have it be smooth and shiny and round, not dull and gray. Then with your side cutters, clip the extra leads off at the joint, done as far as soldering, next to check to be certain it works, obviously.
Good luck!
Edits: 01/13/21
I've got a solder sucker and it doesn't work nearly as good a wick.
I know zip-ah-dee-doo-dah about circuits and can't read a schematic. Look at the circuit board, I have no idea what does what.
But I've successfully recapped two solid state preamps. Go slow, use the continuity setting on your DVOM to make sure all your solder joints are good.
When I did the Halfer DH-101, I did a set of caps, then plugged it in and listened to it to make sure everything still worked.
The problem is not that there is evil in the world, the problem is that there is good. Because otherwise, who would care?
For perfect tone use Columbia Needles
For Best results use Victor Needles
For best results use OKEH Needles
These are the 6 film caps that go under the PCB correct?
Do you have some already soldered in place? If so, and you want to keep the originals without damage to them there are two ways. With the lead in the grasp of pliers, you can heat the soldering pad and gently pull on the lead until it comes out of the solder joint pad. Or you can cut the leads and do the same with less issues. Then you can go back and clean out the rest of the solder in the hole with either solder Wick or one of those cheap desolder hand sucker pump.
You have to add fresh solder to melt old solder. Sometimes tinning, wiping and then tinning again will get it done, sometimes you have to touch the fresh solder to the old. Get a Solder Sucker, bulb or plunger. I don't have enough hands to use the bulb type.I use this one, good enough for occasional work
Quality solder wick is also necessary for boards and pulling apart point-to-point cleanly. You want NTE No Clean the only one I've found absolutely reliable. Use it holding the solder to it as though you were soldering it to the part or board and pulling/rubbing the wick across the part.
Any Damned Fool Knows One Horse Can Run Faster Than Another
Edits: 01/13/21
I usually cut the leads at the body of the old caps. That allows me to grab onto the lead with my pliers after having removed most of the solder with the above recommended items. Then a quick touch of the iron and a pull on the lead and out it comes. Best of luck. Great project.
You really need both of these to do the best job. Then you can do a professional job of unsoldering and resoldering.
It also helps to have a variable temperature soldering iron. I use a Weller Soldering Station.
Good luck,
John Elison
The braid seems like it gets very little, but the plunger/sucker thingy does work if I time it just right. Heat and pull was my plan, but can I get that hole completely clear for the new ones. Do I keep them fairly close to the board with short leads? Sometimes I see them dangling off to the side.....maybe because they're too big for the location.
Edits: 01/13/21
.....just touch your iron to the board and remove the rest from the hole with your solder sucker or wick, The wick may be easier here.
Yes, I prefer to see the caps in contact with the board as that acts as a stabilizing/damping element as regards vibration. When getting the new caps ready for install into the cleaned holes, push the leads through the holes, make contact between cap and board, and slightly bend the leads from the back to hold the cap in place. Solder the holes and, when the solder is dry, cut the leads with your clippers. Voila.
nt
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