- Joined
- Feb 5, 2013
- Messages
- 194
I received my 2 X 3/16 1084 from Aldo and am going to start cutting some of it up in a few minutes. While I'll start with something more simple while I learn the process, one thing I'd like to make are some joinery floats. They're like single cut files, only with MUCH larger teeth - teeth like you'd find on a handsaw (for wood), only they go all the way across:
Like saws, they need to be hard enough to hold and edge but soft enough to resharpen with a saw file, so they're about rc 50-52.
The charts I've seen say that requires around 600-650F for tempering, hotter than my home oven. Luckily it occurred to me my wife almost certainly has access to a high temp lab oven at work - late night HT raids are obviously in order.
My questions:
Warping - The blade is only toothed on one side. I've read one person say you should not cut them until after HT so they don't warp, but seems most people do. Even the purchased ones are a bit warped.
Would coating in satanite when hardening help? (that's a wild guess) Would the choice of quenchant make a big difference? I recall reading about similar problems when forging files and rasps - something about them being straightened while still hot. I don't get how you can straighten while still hot when they warp when quenched. Or does the warpage happen in the furnace?
Tempering - Looks like I need to get it to 600F. (http://www.cashenblades.com/steel/1084.html) I realized this morning that my wife likely has (after hours sneaky) access to a high temp lab oven at work, if not I won't be able to get to 600F with my home oven. What would you suggest for an inexpensive option? I am more interested in learning and trying things out that getting ideal results, so I don't want to send away for HT.
However, on wikipedia I read that 600F falls in a problematic range:
"Tempering in the range of 260 and 340 °C (500 and 644 °F) causes a decrease in ductility and an increase in brittleness, and is referred to as the "tempered martensite embrittlement" (TME) range. This range is usually avoided. Steel requiring more strength than toughness, such as tools, are usually not tempered above 205 °C (401 °F). Instead, a variation in hardness is usually produced by varying only the tempering time." (http://en.wikipedia.org/wiki/Tempering - see "Quenched Steel" section.)
I've had no luck finding further information and on the TTT diagram both temperature and hardness are on the same dimension - I'm missing something.
Thanks for both your answers here and the great wealth of information shared on the site in general.

Like saws, they need to be hard enough to hold and edge but soft enough to resharpen with a saw file, so they're about rc 50-52.
The charts I've seen say that requires around 600-650F for tempering, hotter than my home oven. Luckily it occurred to me my wife almost certainly has access to a high temp lab oven at work - late night HT raids are obviously in order.
My questions:
Warping - The blade is only toothed on one side. I've read one person say you should not cut them until after HT so they don't warp, but seems most people do. Even the purchased ones are a bit warped.
Would coating in satanite when hardening help? (that's a wild guess) Would the choice of quenchant make a big difference? I recall reading about similar problems when forging files and rasps - something about them being straightened while still hot. I don't get how you can straighten while still hot when they warp when quenched. Or does the warpage happen in the furnace?
Tempering - Looks like I need to get it to 600F. (http://www.cashenblades.com/steel/1084.html) I realized this morning that my wife likely has (after hours sneaky) access to a high temp lab oven at work, if not I won't be able to get to 600F with my home oven. What would you suggest for an inexpensive option? I am more interested in learning and trying things out that getting ideal results, so I don't want to send away for HT.
However, on wikipedia I read that 600F falls in a problematic range:
"Tempering in the range of 260 and 340 °C (500 and 644 °F) causes a decrease in ductility and an increase in brittleness, and is referred to as the "tempered martensite embrittlement" (TME) range. This range is usually avoided. Steel requiring more strength than toughness, such as tools, are usually not tempered above 205 °C (401 °F). Instead, a variation in hardness is usually produced by varying only the tempering time." (http://en.wikipedia.org/wiki/Tempering - see "Quenched Steel" section.)
I've had no luck finding further information and on the TTT diagram both temperature and hardness are on the same dimension - I'm missing something.
Thanks for both your answers here and the great wealth of information shared on the site in general.