SkuttleFunk said:
CB ... I'm curious what experiences you draw upon to form your comments on this subject. Not picking a fight, just wanting to know the experience you have that has brought you to your preferences
... counts the years....
24 years of direct hands on component level board repair in the industrial control and communications fields, 18 of which were at the management level of a rework/repair department that saw about 40 boards per day at times. I have direct hands on experience with technologies ranging from eyelets and turrets to through-hole to surface mount, on single and multiple layer boards. I have attended the excellent PACE schools (should add, some of that was USN based, but I was civilian there), and have taught a similarly structured school for my employees. I have set up now, three rework shops, each with multiple workstations, filtration and ventilation, board washers, shop air, chem dispensing, you name it... the only thing we don't generally do is have high voltage DC on demand. Thats usually done via variac feeding a transformer and rectifier, as each situation demands.... and I don't see to much of that in the controls - its all 24vac or 120vac, plus logic at low DC. (sure, I set up the shops so I can.....tinker there as well!~)
As far as burning up pots, never seen one burn up on the case from too little heat, but have toasted a few substrates in my day. Gibson pots are by far the worst in that category. But... if you try you can melt just about any of the newer non-fibre substrates. Pretty easily too. I see CTS using fibre and non-fibre. I see Clarostat (now THERE's a good pot, but at $18 each... whoababy!!) using only glass substrate.
Same thing on those CRL type switches. Some are ok (the brown wafers not too bad) but even then, the rotor is usually plastic. The tan wafers are.. less than ok if you get them hot. The whitish creme color ones just melt to pieces.
Most components we see in guitars - capacitors, the occasional resistor are ok for the heat. FWIW, most of the nasty looking "overheated" pots are just that, just nasty looking and work ok, not melted inside or such... they just have burnt flux on them.
I had a run of tube sockets I imported from "mother russia" and they all had some nasty crap on them, made me think of the "black oil" thing in "The X Files". Was a mother and a half to clean up, but once it was, they did ok. Also had some gold plated sockets from same source - Novosibesrk - and they were a pure joy, and I've still got some of those left. Ran into some "bad" supposedly "vintage" black fibre board from a well known speaker blowhard, that melted as you tried to do anything with it. The real stuff does not do that. Similarly, I've seen so-called G10 board that is not. G10 only comes from Westinghouse, is not yellow but a very light creme color and is impossible to overheat with any sort of normal soldering iron, and... is nasty as hell to drill, quickly wearing out the points. I found a local source from a buddy at MCI, that sells solid carbide board drills and stocks them in .125 and .1325 for eyelets (or at least I use them for eyelets). I had to finagle to get an account with them, but hopefully... we'll be good friends in the future. I have... about two cut up 4x10 foot sheets of Westinghouse board left in my garage, all set up in widths for replacement into Fender chassis (tweed through silverface).
In addition, I do what I call "ghost-soldering" for several local shops, taking in only eyelet board Fenders and older Marshall, and... the guitars.
Gotta say, the only thing I pull out the "big iron" for is those Fender chassis grounds which I reflow whenever in there. And I'm serious when I say, gimme a clean pot, and soldering to it is a no brainer with 18w or 15w. I have a good selection of older Ungar stuff, and .... keep those around for that sort of thing (the PACE stuff is all at the shop).
I know that folks have different techniques... but also know the industry accepted practices, especially when if comes to beginners needing to learn the right way, before they go off on their own to make their own mistakes <gggg>. The old "Elmers" of this world take educated, experienced shortcuts... and get by with few mistakes, but... thats experience hard earned and long learned.
To that last statement, when I put the do-nothing, all thumbs, draws pictures of boats all day long, son of the company owner's son through class and had him doing rework that afternoon... I know the methodology works if presented well, and applied correctly. For a real fuckup, the kid did ok (kid still at 24, never really "earned" a cent in his life).
Sort of stuff I do
8 channel 24v control board - check out the burnt ones behind it!~
wireless network node, used in local data telemetry
Parts Dept
we have lots of parts!
The old test fixtures (no pics of new yet)
This stuff is viable, but... not very organized for workflow... thats being corrected
Old workstation #1 (its gettin redone, and a royal mess right now)
This... is an abortion of a workstation, and its worse now, but.. I have a plan to get it right.
Just a shot of my two LPs for the hell of it....