This is a re-post as I see that I thoroughly messed up the subject line 
on my previous attempt.

I have some Alpha metals silver bearing solder (perhaps like 4% silver) 
(I lost the package so I can't reveal the brand name)  -  but the tube 
of liquid flux that came with the kit says, "lead free silver solder 
flux"  "for non-electrical applications #53982" (couldn't loose that 
info cause it's printed on the tube and hasn't worn off yet) that works 
quite well with stainless steel and the like and i would bet at least a 
quarter that it would work with nichrome. I have some other stuff  - 
self fluxing 6% silver solder kit but cleverly cut off the brand name. 
In general, these solders work well  in a stainless steel type 
environment and can be bought at the hardware store for little money. - 
You definitely need the acid or similar type flux - no rosin flux and 
then wash well to prevent corrosion- perhaps even start with a baking 
soda rinse. These solders also work fine for copper metals and I have 
used them a lot for lower temperature thermocouple junctions (below the 
solder melting point!) By the way, they work at soldering iron temperatures.

I have also been known to sand or scrape "up" stock resistors both 
carbon and metal film - should work with wirewound too but then there is 
the inductance. I bet you could sand large surface mount resistors too.
I just grabbed a 10 ohm surface mound and easily scraped the coating off 
with an exacto knife and found the resistor layer to be much harder- 
probably need an abrasive (fine sand paper like 2000 grit) to grind that 
down some. By the way, this resistor has a rectangular area with a 
(probably laser) cut halfway through the rectangle, like they only fab a 
few values and then trim to the desired value.
Of course there is always the option of using two or more resistors 
(parallel is probably best for low values) which is what I do if I want 
the result to be really stable but I'm sure you don't need ME to tell 
you about that solution.

On that note, or rather off that note, does anyone know how to make 
stable (dry) LARGE value resistors like >100mohm or even like 10 or 100 
gohm roll your own resistors.
-- 

Looking forward,
Al Shinn

-- 

Looking forward,
Al Shinn




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