Shanghai McCoy
Member
Thanks for the epoxy info Sam. Bet that tester/tac-toku makes a good "thunk" when you throw it into the target.
The Sam Cade Thread of Knifey Goodness
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Sam Cade
Member
Wasting a bit of time today.
We have a professional lawn service in the family so we have piles of worn out mower blades lying around.
These are from a big beastly eXmark and are pretty well kaput.
Judging by the sparks the blade is some sort of high carbon steel and is probably suitable for cutlery use.
http://en.wikipedia.org/wiki/Spark_testing
Using a chop saw I lop off the flat sections of blade. This gives me two 6" lengths of 5/32" thick steel.
Yes, hso, I could have forged it flat but it is HOT out there today.
Giving one of the sections an experimental poke with a fresh bit in the drill press lets me know that the blades are indeed hardened. Too hard to drill is too hard to grind without undue investment of effort.
We are going to anneal this by heating it up past critical and letting it cool slowly.
Slooooowwwwwllllly.
So into the forge we go. I bring it up past critical, soak it for 10 min for good measure, then simply brick up the forge and let it rest for a few hours.
We have a professional lawn service in the family so we have piles of worn out mower blades lying around.
These are from a big beastly eXmark and are pretty well kaput.
Judging by the sparks the blade is some sort of high carbon steel and is probably suitable for cutlery use.
http://en.wikipedia.org/wiki/Spark_testing
Using a chop saw I lop off the flat sections of blade. This gives me two 6" lengths of 5/32" thick steel.
Yes, hso, I could have forged it flat but it is HOT out there today.
Giving one of the sections an experimental poke with a fresh bit in the drill press lets me know that the blades are indeed hardened. Too hard to drill is too hard to grind without undue investment of effort.
We are going to anneal this by heating it up past critical and letting it cool slowly.
Slooooowwwwwllllly.
So into the forge we go. I bring it up past critical, soak it for 10 min for good measure, then simply brick up the forge and let it rest for a few hours.
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Sam Cade
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50 Shooter
member
Sam,
Have you ever made any knives out of leaf springs? Is the steel any good? Seeing how you could go to a junk yard and get a lifetime supply in one shot...
Have you ever made any knives out of leaf springs? Is the steel any good? Seeing how you could go to a junk yard and get a lifetime supply in one shot...
Forges aren't terribly difficult to make thanks to all the ABANA and ABS folks publishing plans and examples.
Still, you get much better control and efficiency with the more advanced forges, but you can do a lot with a properly laid out "pile" of refractory brick and a good burner setup.
Lots of smiths are selling "coffee can" forges out there that aren't much more advanced.
Leaf spring "billets" are good if you know you're getting them from a quality source. I have a pile of 1960s coal truck springs that have proven to be pretty consistently good for blades (donated to the ABS for the Youth Hammer-In program).
Sam, do you have a pile of vermiculite you can use for a slow cool-down?
Still, you get much better control and efficiency with the more advanced forges, but you can do a lot with a properly laid out "pile" of refractory brick and a good burner setup.
Lots of smiths are selling "coffee can" forges out there that aren't much more advanced.
Leaf spring "billets" are good if you know you're getting them from a quality source. I have a pile of 1960s coal truck springs that have proven to be pretty consistently good for blades (donated to the ABS for the Youth Hammer-In program).
Sam, do you have a pile of vermiculite you can use for a slow cool-down?
Sam Cade
Member
Sam Cade
Member
Remember that you can burn carbon out of the steel if you leave it to soak at those temps too long.
Sam Cade
Member
Not yet.I've owned a bunch though. I'm not hardly doing any forging as yet. I'm focusing on getting the grinding and finishing end of things nailed down at the moment.
A resounding probably.
The downsides are of course that all steel isn't created equal and there is going to be a labor investment in the steel just getting it ready for use.
Good clean, annealed, consistent, virgin steel is cheap and gets cheaper when purchased in quantity.
Sam Cade
Member
I had that concern, but I figure that it would drop out of the molecular boogie woogie end of the curve fast enough that it probably wouldn't matter. You wouldn't happen to have a thermocouple in your pocket would ya?
The spark doesn't seem to have changed. I guess we will find out when we try to harden it.
Sam Cade
Member
I'm wounded you had to ask!
Actually, I gave a non-contact IR device to a knifemaker not too long ago and it improved reproducibility significantly for forging.
Sam Cade
Member
I've built a couple small sled jigs but I don't bother with it most of the time since I don't feel like I'm developing any skill by sliding it around.
..and they aren't any fun to use.
..and they aren't any fun to use.
Re: Laser Thermometer
Yes, but the high temp variety instead of the "what's the temp of my steak or engine block" sorts. I stay on the lookout for old engineering/lab equipment that can be gotten inexpensively and that might be useful in forging (up to 2,500 F), but the prices on these thermometers have dropped to the point that finding the old clunky gear isn't worth it at time when you can luck into one of these for around $100 rated up to 2,900 F. http://www.ebay.com/itm/HT-6889-Non...407?pt=LH_DefaultDomain_0&hash=item4861865347
Yes, but the high temp variety instead of the "what's the temp of my steak or engine block" sorts. I stay on the lookout for old engineering/lab equipment that can be gotten inexpensively and that might be useful in forging (up to 2,500 F), but the prices on these thermometers have dropped to the point that finding the old clunky gear isn't worth it at time when you can luck into one of these for around $100 rated up to 2,900 F. http://www.ebay.com/itm/HT-6889-Non...407?pt=LH_DefaultDomain_0&hash=item4861865347
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Sam Cade
Member
Lawnmower blade mystery steel knife ground and profiled.
Went with a thicker, more idiot resistant grind than I normally do. Also, no hand finishing on this one. Just chased the flats with a palm sander. Or rather, locked the palm sander in a vise and rubbed the flats on the business end for a couple minutes.
Left-over serial number. Kinda cool.
Heat treat looks like it was at least a limited success, the blade got harder than woodpecker lips from a warm canola quench.
Went with a thicker, more idiot resistant grind than I normally do. Also, no hand finishing on this one. Just chased the flats with a palm sander. Or rather, locked the palm sander in a vise and rubbed the flats on the business end for a couple minutes.
Left-over serial number. Kinda cool.
Heat treat looks like it was at least a limited success, the blade got harder than woodpecker lips from a warm canola quench.
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50 Shooter
member
Uuuhm Sam... We're waiting for the next installment sir!!!
Now that you have your own little thread don't you know you're supposed to keep us up to date? Tic tock tic tock, its not like we have all day here...
Now that you have your own little thread don't you know you're supposed to keep us up to date? Tic tock tic tock, its not like we have all day here...
Sam Cade
Member
No worries. I've been moving some shop stuff around and working on a rebuild on an aluminum decked pontoon boat.
Also invaded Poland, thanks to BullfrogKen.
https://www.paradoxplaza.com/hearts-of-iron-iii-collection
I'm fixing to wander out to the shop and make some sparks here in a few.
Also invaded Poland, thanks to BullfrogKen.
https://www.paradoxplaza.com/hearts-of-iron-iii-collection
I'm fixing to wander out to the shop and make some sparks here in a few.
Deltaboy1984
Member
Keep up the Good work.
Great to see the process
Sam Cade
Member
Have I ever told you folks how much I hate, hate hand sanding the belt scratches out of a blade?
It is boring and takes forever, by far the most time consuming part of the process.
So I've decided to never do it again...or at least to do it as little as possible.
Behold!
The SKIL 1/4 sheet vibratory palm sander with vacuum filter dohickey.
Less that $30 at your preferred big box store or $10 at the local pawnshop.
...and here it is clamped upside down in a vise ready to work on sanding out some knives.
Just rub the flats on the paper while the machine runs. Easy Peasy. It would be difficult to mess this up.
A couple minutes with a 120 grit square of sandpaper takes an 80 grit belt finished blade to this:
..and to 320 grit:
It is boring and takes forever, by far the most time consuming part of the process.
So I've decided to never do it again...or at least to do it as little as possible.
Behold!
The SKIL 1/4 sheet vibratory palm sander with vacuum filter dohickey.
Less that $30 at your preferred big box store or $10 at the local pawnshop.
...and here it is clamped upside down in a vise ready to work on sanding out some knives.
Just rub the flats on the paper while the machine runs. Easy Peasy. It would be difficult to mess this up.
A couple minutes with a 120 grit square of sandpaper takes an 80 grit belt finished blade to this:
..and to 320 grit:
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Sam Cade
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The machine will utterly wear out a 1/4" piece of sandpaper in just a couple minutes. Once worn out I just move up to the next grit.
In less than 15 minutes I went from nasty belt finish to this:
I'd say that is more than adequate for a working knife. It would be easy to move up to a true mirror finish from here if a person was so inclined.
Dig the tailhook on this little guy.
In less than 15 minutes I went from nasty belt finish to this:
I'd say that is more than adequate for a working knife. It would be easy to move up to a true mirror finish from here if a person was so inclined.
Dig the tailhook on this little guy.
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