Grinding and heat treatment

BlackKnight86

BlackKnight86

Say my name, cheesers!
Joined
Oct 14, 2003
Messages
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Those of you who do any kind of grinding on your Busses...is there a risk of affecting heat treatment if you let it get too hot? If so, what is the "danger zone", and what do you do to avoid it? Is there a set temperature to watch out for? How do you watch out for it? Is it speed or length of time with the grinder? Or do you gauge it by temperature of the steel?

Is it a risk only with powered grinding, or can it occur when you grind the metal manually? Is it even possible to do serious grinding (like shaping a pommel) manually; or are we talking way too much time and effort?

Thanks!

BK86
 
It is a serious risk, much more so near the edge. It voids the garantee. But I did it anyway :D

More knowledgeable knifenuts will chime in, but here's what I do: I keep a finger as near as securely possible to the work, and as soon as I can feel heat, I stop and let it cool in water. i go SLOW, with minimal pressure. The edge is more critical because it is thin.

You guys must be sick of seeing this knife, but here's the result:
Before:
Before.jpg


After:
After1.jpg


After3.jpg
 
there isnt much of a risk getting a blade too hot by hand sanding. using any electric sander or grinder will get the steel too hot if you're not careful. i do any regrinding bare handed and on a slow running belt sander. i keep a bucket of water handy and if the blade feels warm in my hands i quench it. most often i quench every few passes just to keep the blade cool even if its not warm. a blade can handle some heat just as long as you dont get it to turn colors.
 
about 150 degrees is where you can hold it in your hand with minor discomfort! the water and keeping the blade cool is the key,, USE NEW BELTS ON MODS!!! a dull one will cause too much friction making the blade temp rise much more rapidly.
 
I thought I read somewhere once (a while back) that a Busse Basic can withstand falling into a campfire, melt the handle, and still be a perfectly good knife. I was always under the impression that it was harder to damage the heat treat of a Busse knife as compared to other knives. Anyone else remember reading these things? I don't want to spread anything false around, I just thought I remembered something to that effect.
 
I seem to recall someone quoting Jerry that INFI was safe up to 900F. Based on that, I don't think there is a serious risk if one uses a little common sense. Hand sanding/filing could not possibly hurt it. When I use the HF belt grinder, just keep a bucket of water there for a dip every few passes.
 
verpus77 said:
I thought I read somewhere once (a while back) that a Busse Basic can withstand falling into a campfire, melt the handle, and still be a perfectly good knife. I was always under the impression that it was harder to damage the heat treat of a Busse knife as compared to other knives. Anyone else remember reading these things? I don't want to spread anything false around, I just thought I remembered something to that effect.
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Yeah, I've read that too. But there's a difference between dropping it in a campfire, and grinding away on a fine edge.

The grinding causes heat to build up very quickly, so quickly that the energy might not be able to conduct away into the bulk of the blade before that thin edge overheats.

Lot of energy + thin metal + slow transfer away = High Temperature
 
DONT BE LAZY! Just Kidding man! :p

this is what I live by;

Slow is steady, steady is fast. :thumbup: got that from a sniper book, forgot which one though...

I always hear the 900 degree F thing to...
 
Horton_Knives said:
about 150 degrees is where you can hold it in your hand with minor discomfort! the water and keeping the blade cool is the key,, USE NEW BELTS ON MODS!!! a dull one will cause too much friction making the blade temp rise much more rapidly.
Click to expand...

resinguy said:
I seem to recall someone quoting Jerry that INFI was safe up to 900F. Based on that, I don't think there is a serious risk if one uses a little common sense. Hand sanding/filing could not possibly hurt it. When I use the HF belt grinder, just keep a bucket of water there for a dip every few passes.
Click to expand...

Yeah what they said! :thumbup:
 
Fresh belts, very little pressure when touching the INFI to the belt, and frequent dipping in water. Keep heat to a minimum and do not wear gloves while grinding as they will keep you from feeling any heat. Work slow and carefully and you will be fine :)
 
foxyrick said:
Yeah, I've read that too. But there's a difference between dropping it in a campfire, and grinding away on a fine edge.

The grinding causes heat to build up very quickly, so quickly that the energy might not be able to conduct away into the bulk of the blade before that thin edge overheats.

Lot of energy + thin metal + slow transfer away = High Temperature
Click to expand...

Couldn't say it better. Be Careful.
 
When I was a kid, my optometrist had a rig for shaping eyeglass lenses. It was a round stone maybe 2 or 3 inches wide and about 2 feet in diameter and was motorized to spin like a bench grinder but slowly. It had a water system that kept a layer of water on the surface of the stone. I've never seen anything like that again. Seems like it would be perfect for grinding edges.
 
MRpink said:
:confused: Really? :confused:
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One shouldn't expect Busse to replace a blade anyone other than the shop took to a grinder. If you broke your blade or had major damage after making a major modification on your own, how could they know for sure that the failure was due to their materials or your workmanship? Just like Jerry wouldn't cover it if you took your blade out and cut it in half with a blow torch, nor should he if you make major modifications involving the removal of a significant amount of stock and in so doing ruin the temper. Stripping the coating with chemical is one thing, major re-profiling is another. At least that is the way I see it.
 
Progunner said:
One shouldn't expect Busse to replace a blade anyone other than the shop took to a grinder. If you broke your blade or had major damage after making a major modification on your own, how could they know for sure that the failure was due to their materials or your workmanship? Just like Jerry wouldn't cover it if you took your blade out and cut it in half with a blow torch, nor should he if you make major modifications involving the removal of a significant amount of stock and in so doing ruin the temper. Stripping the coating with chemical is one thing, major re-profiling is another. At least that is the way I see it.
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Agreed, when a blade is modified, like my Ban-ned knives or the SAR5 I cleaned up on the HF grinder, I know I have to trust the inherent properties of the INFI, rather than the warranty.
 
shunsui said:
When I was a kid, my optometrist had a rig for shaping eyeglass lenses. It was a round stone maybe 2 or 3 inches wide and about 2 feet in diameter and was motorized to spin like a bench grinder but slowly. It had a water system that kept a layer of water on the surface of the stone. I've never seen anything like that again. Seems like it would be perfect for grinding edges.
Click to expand...

They're still around, although I've not seen a 2' one. They make small ones for lapidary work (gemstone grinding) and larger ones for tool blades. The water carries away the grinding debris as well as keeping things cool. I've never used one although my father has one for chisels.

Years ago around here (so I'm told) the Gypsies used to have modified bicycles with grind wheels on, so they could prop the bike and peddle to spin the stone. They went around charging to sharpen folks knives.


I often use a power file to profile my edges, and restore them if they get really blunt or chipped. It's like a mini belt grinder with a 1/2 inch belt and 8" of working length. I keep it on its slowest setting and take it slow and easy. No need to rush; it's still way faster than doing it by hand. Probably no good for really removing stock though, if major modifications are desired.
 
Progunner said:
One shouldn't expect Busse to replace a blade anyone other than the shop took to a grinder. If you broke your blade or had major damage after making a major modification on your own, how could they know for sure that the failure was due to their materials or your workmanship? Just like Jerry wouldn't cover it if you took your blade out and cut it in half with a blow torch, nor should he if you make major modifications involving the removal of a significant amount of stock and in so doing ruin the temper. Stripping the coating with chemical is one thing, major re-profiling is another. At least that is the way I see it.
Click to expand...

For mods I understand, but sharpening on a belt sander shouldn't void the warranty right?
 
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