From: djb@invalid.com   
      
   On 21/02/2026 21:31, Jim Wilkins wrote:   
   > "David Billington"  wrote in message   
   > news:10nctj4$17n49$2@dont-email.me...   
   >   
   > On 21/02/2026 17:48, Jim Wilkins wrote:   
   >> "David Billington"  wrote in message   
   >> news:10ncf0a$17n49$1@dont-email.me...   
   >>   
   >>> ...I tried a mix I found online   
   >> which called for them as part of a recipe for preventing/reducing   
   >> firescale on steel during heat treatment and it didn't seem to work very   
   >> well, subsequently I got some Condursal Z1100 and that seems to work   
   >> well, cost more but does what it says on the tin.   
   >> -------------   
   >>   
   >> Natural sodium stearate soap (Ivory) works pretty well in combination   
   >> with a closed tube containing charcoal or sawdust.   
   >>   
   >>   
   > Yes my other option is stainless tool wrapping foil which I use for some   
   > items when tempering/normalising and include some wood inside to   
   > scavenge the oxygen remaining which results in just minor discolouration   
   > like from tempering, no scale. The Condursal was for use with items to   
   > be hardened so I could drop them straight into the quench tank without   
   > having to remove the foil.   
   >   
   > ---------------------------------   
   >   
   > I have some of that foil too and use it sparingly on longer items.   
   > Short tools go in a soup/vegetable can with the lid not completely   
   > removed, so the tool can be extracted with tongs or shaken out above   
   > the quench, which if oil is in the door opening of the wood stove.   
   >   
   > A can on its side with a floor of charcoal contains a propane torch   
   > flame well enough to evenly heat a tool larger than it could in free   
   > air. The burning charcoal contributes a lot of distributed infrared.   
   > The flame needs to swirl inside the can and have a place to exit,   
   > straight in doesn't work so well.   
   >   
   I've got a small Gallenkamp Hotspot kiln bought for enamelling but good   
   for heat treat as it'll go to about 1050C, and a 18" top loader ceramic   
   kiln which gets used for larger pieces such as normalising CRS when   
   required. Both are controlled with PID controllers with thermocouples   
   which are added on and the kilns plug into them and the power controller   
   set to 100%. One is just ramp/soak the other can take more complex   
   heat/soak/cool if required.   
      
   The oil quench tank is made from a truck air receiver with the end cut   
   off which forms a lid and can be closed if required such as if the oil   
   caught fire which it hasn't so far. That is heated with a metal sheathed   
   mineral insulated electric element and controlled with a cheap (£15?)   
   mains thermistor controller with the thermistor and exposed lead in a SS   
   sheath to protect it from the hot oil. I remember an episode of 'Forged   
   in Fire' where a guy set his workshop on fire after leaving his quench   
   tank to heat on an open flame heater and it caught fire when the oil   
   expanded and overflowed, I don't want to go there.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)