Fender Bassman 20 cap job

[Fred G.]

HELP!! I'm working on an early '80's Rivera era Fender Bassman 20. A "routine" cap job has become a total nightmare. The multi-cap can is the problem - I CANNOT get it out of the chassis. Fender, in their infinite wisdom, soldered all 4 ground lugs DIRECTLY to the chassis. I scored a 100W used American Beauty iron off Ebay - it works fine, except - all I seem to be doing is just "melting solder" and pushing it around. The solder wick I'm using, which is normally fine for lighter duty work, isn't wicking at all! The iron seems to be powerful enough, but the 4 massive lakes of solder are overwhelming the tools I'm using. PLEASE - can anyone provide specific, detailed instructions on how to get this damned cap can out? FYI - there is NO room in this chassis for any kind of creative capacitor creation, it's gotta be a multi-cap can. I barely have enough room to get the massive 100w Iron in there, even after removing the fuse holder and pushing the filament wiring away (may have to disconnect that, too). I would really appreciate detailed suggestions - do I need flux? A different SPECIFIC brand/spec of desoldering braid? Flux? HELP!

[Jazz P Bass]

How about a pic?
You may have to resort to a low melt solder like chip quick.

[SoulFetish]

Sure, here 's what to do:
You mentioned that your soldering iron is up for the job of melting the solder,so I'll assume that's the case. Your going to need a solder helper tool, like one of these -

(but you may be able to use flathead screwdriver with the blade filed to a fine edge)
You're going to need to melt the solder with your iron and once it's wet, use the screwdriver tool, or forked tip tool to wedge between the lug and chassis and pry it away. You should be able to separate it, and free the lug from the chassis.

[garytoosweet]

I always use flux with desoldering wick.

You can use a solder sucker like an Edsyn Soldapullt.

Sometimes you can cut the tabs off with diagonal cutting pliers (big ones, not the ones used for cutting component leads) or a rotary tool like a Dremel. The can will drop, leaving the tabs soldered to the chassis. You can then heat the tabs with your iron and slide them off.

[The Dude]

I use a Weller gun for those jobs- not sure of the wattage. Even then, I'll usually progress around the cap- heat a lug, straighten it if bent, apply a little down pressure and repeat on the next one over. Keep going until all lugs are "rocked" out of the slots. I don't remove the solder except to clear the holes. That makes it easier to add a little solder and install the new can. It's kind of a feel thing to know how much pressure you can use without bending up the chassis.

[Fred G.]

I finally got the damned thing out! I had pushed enough solder away from one "seam" to where I could see some separation from the bracket and the chassis. A few gentle taps with a flat head screwdriver and hammer separated one joint enough to where I could grab it, and with a few gentle tugs and twists, the whole assembly broke free from the chassis. What a PITA...lol. Thanks everyone. SoulFetish - I definitely will invest in a set of those soldering picks!

[Enzo]

Forget wick, you are thinking in terms of wicking away solder leaving a bare joint. You need to think in terms of removing the part.

In my view, wick requires more heat. A solder sucker would remove melt without having to heat both chassis and wick.

As others suggest, melt around one tab, and get under it with a small tool.and bend it up; from the chassis. That should make it easier to remove solder from teh tab without having to pull it off the chassis too.

In fact, you are going to replace it so why not grab each tab with pliers and bend it back and forth until it breaks off. Now the cap ought to pull out easy.

Or a cutoff wheel on your Dremel tool could grind the tabs away.

And I also would be using my ancient Weller 100/140 watt solder gun. A little 40 watt solder iron won't cut it.

Fender did it this way because it is strong, secure, and reliable. You are just now replacing the cap, it lasted 40 years. They had no reason to design for replacing those cans every few months or anything.

[vintagekiki]

... I definitely will invest in a set of those soldering picks!

Soldering iron in complete with desoldering vacuum pump.
For heavy work I use a soldering iron 150W with a massive wide tip (Tinsmith Tool)

useful links
https://www.eevblog.com/forum/beginners/what-desoldering-gunpump-is-best/

https://www.eevblog.com/forum/reviews/whats-a-good-solder-sucker/

[Leo_Gnardo]

Fender, in their infinite wisdom, soldered all 4 ground lugs DIRECTLY to the chassis. I scored a 100W used American Beauty iron off Ebay - it works fine, except - all I seem to be doing is just "melting solder" and pushing it around.

Fender, in their infinite wisdom, did the same in Champs, Princetons and other amps too. So did hundreds of other companies, guitar amps, hi fi gear, and every other kind of electronic gadget.

I've never had much luck with the Weller 100+ watt "guns" BUT I have recommended on these pages the very tough and able Weller SP-80, a soldering "pencil" sized for King Kong. The mass of the tip is what does the trick. Once the iron is fully "het up" it's child's play to melt those chassis connections. Last I looked these were only about US$30, an affordable and worthwhile addition to your tool collection.

For even bigger jobs, there are 120 and 160W versions. Mine was donated by a stained glass builder. It was getting old & tatty, looked like the AC cable was about to quit. Now it's 33 years later, it still works, it's done the trick scores of times when lesser irons would have failed. And I bought a spare, with bright orange "can't get lost" handle but still unused because the old one just won't quit.

https://www.amazon.com/Weller-SPG80L...00GR3NMY&psc=1

^^ link to the latest SP80 version, $32.62 including delivery from Amazon. If you want to go full Cap'n Billy Whiz-Bang there's a version with a built in LED array to spot light your soldering site, a rock solid bargain at only $21.04. Link below:

https://www.amazon.com/Weller-SP80NU...0B3SG796&psc=1

Stop suffering and learn to sing the blues - get one of these and we'll hear no more of it, except I hope, a good review!

[garytoosweet]

^^ link to the latest SP80 version

I went through 3 or 4 of the SP80 in the last year or so. Would only plug them in long enough to heat up, make my 1 or 2 chassis connections, then unplug immediately. They could only stand this cycle 2 or 3 times before the heating element died. Weller would replace it under warranty, but what a pain. Many reviews online share the same experience, so I can not recommend this iron. I'm sure the 30+ year old one you have is a much better quality than what is being sold today. In the end I bought an ancient 100W American Beauty locally and it's been great so far.

[Leo_Gnardo]

I went through 3 or 4 of the SP80 in the last year or so. Would only plug them in long enough to heat up, make my 1 or 2 chassis connections, then unplug immediately. They could only stand this cycle 2 or 3 times before the heating element died. Weller would replace it under warranty, but what a pain. Many reviews online share the same experience, so I can not recommend this iron. I'm sure the 30+ year old one you have is a much better quality than what is being sold today. In the end I bought an ancient 100W American Beauty locally and it's been great so far.

Wow, I am surprised and dismayed. Maybe it's best for me the old iron keeps on truckin'. In that case then... people be on the lookout for working old secondhand big irons at your local garage sales & Craigslist etc.

[SoulFetish]

Wow, I am surprised and dismayed. Maybe it's best for me the old iron keeps on truckin'. In that case then... people be on the lookout for working old secondhand big irons at your local garage sales & Craigslist etc.

I'm with you, Leo. I was pumped to pick one of these up. My boss's old light blue 100W'er is still working great, and seems to be fine staying powered on for over an hour (sometimes a few). But the power cord input to the handle has more tape than than a Roland Space Echo.
Now what are we gonna do?

[Enzo]

Y,know, my trusty old Weller 100/140 gun has been with me for decades, seriously, like 60 years. 140 watt is with the trigger fully in and 100 at the middle click. SInce I usually use the 100 watt, I went inside and swapped the wires on the switch, so fully pulled is 100 watt, and boost by middle click for 140.

The official Weller tips work fine, but in a pinch I long ago found a few inches of plain old bare 12ga copper wire folded over works fine too, and costs nothing. The wire slowly erodes away - just like a real tip - and generally parts in the tip area. And that is when I discovered resistance soldering. The two halves of a broken tip can be pushed together to make heat. But in the case of some metal object I can poke the two broken tip ends into the metal and the gun current flows through that metal making it heat itself. On a Fender chassis for example, that small pool of solder on the chassis can be heated in that manner.

[The Dude]

You've got me beat. I've ONLY had mine for about 45 years. It's got some cracks in the plastic housing. The power cord is taped together. And, it probably has a broken tip bent around itself so that it still works.

"it probably has a broken tip bent around itself"- If you have had one of these for any length of time, you know exactly what that means.

[Enzo]

Oh yes, twist together, or maybe bend one end to poke into the other end curve,.

I did replace the plastic body on mine at some point, too many times it hit the cement floor. And at some other time I replaced the old power cord with a nice 10 footer.

There is nothing to the things, they are nothing more than a transformer. The metal "pipe" you install the tip into is really a single turn secondary to the transformer.