Ok, I have had several kinds of handle materials on many different folders. The handles have seemed to developed cracks near the pins with normal use. I have seen this in the derlin, bone and horn variations. My question is that does anyone else experience this with these materials and what has been your luck with other materials like micarta or woods. Sorry for no pictures but I can update when I get back in town if need be. Thanks in advance!
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Handles cracking?
- Thread starter mrrampro
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I collect Schrades, and the open stock Delrin models were prone to center pin cracks. In fact, that's where I see alot of pin cracks. Probably due to stress on the spring somehow.
Wood seems the most stable, IMO. Micarta also decent. Horn and bone are more likely to develop cracks, but alot of that has to do with how they were assembled.
Of course, you see alot of bone handled knives that are 100 years old, and the bone is as solid as the day they were sold.
Glenn
Wood seems the most stable, IMO. Micarta also decent. Horn and bone are more likely to develop cracks, but alot of that has to do with how they were assembled.
Of course, you see alot of bone handled knives that are 100 years old, and the bone is as solid as the day they were sold.
Glenn
Will Power
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I've found delrin to be the main culprit here. It must be a weaker material.
Had a GEC 73 in Bone with a VERY heavy spring that cracked at the centre pin after a few days (it was replaced by a new knife no question by the seller). Probably a hairline that worsened due to stressing.
Stag has a lot of natural cracks&fissures but I've found it to be more sturdy than most bone, probably because it's more pliant and less brittle?
Had a GEC 73 in Bone with a VERY heavy spring that cracked at the centre pin after a few days (it was replaced by a new knife no question by the seller). Probably a hairline that worsened due to stressing.
Stag has a lot of natural cracks&fissures but I've found it to be more sturdy than most bone, probably because it's more pliant and less brittle?
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Delrin, in it's current form for knife handles anyway, is very resistant to cracking. On newer knives I have with it, the stuff is practically bulletproof, and very flexible. BUT, older knives with older versions of Delrin may be different. Delrin (as officially named by Dupont) has undergone about a zillion formulation changes since it was invented back in the '50s. And even now, there are a lot of different recipes of Delrin, manufactured for different purposes. Some versions are formulated for better shock-resistance, some for higher strength/rigidity, others made for high-finish/low-friction qualities. And there are other synthetics very similar to Delrin, but trade-named differently.
Some older synthetics were more vulnerable to hardening & cracking, due to exposure to sunlight or harsh chemicals (solvents). A lot of older synthetic-handled knives kept in display cases, over many years' time, will show fading/warping/cracking issues on the side that received the most sunlight.
As mentioned, bone especially will crack pretty easily. It's very hard & rigid, and won't 'flex' as much as would be ideal for use on a pinned handle, where the pins move in response to stresses placed on them (such as with the anchor pin for the spring). And the drilled holes for the pins can introduce additional weakness, if the drilling itself starts a crack or chips the bone, or if the holes are drilled too close to the edges (too thin). I think a well-designed and constructed knife would allow for some movement of the pins within slightly oversized holes in the bone or, better yet, make sure the pins are sturdy enough and well-anchored in the liners, so they won't move at all. Some knife frames also flex or bend, as a whole, which can create stresses on the scales.
Some older synthetics were more vulnerable to hardening & cracking, due to exposure to sunlight or harsh chemicals (solvents). A lot of older synthetic-handled knives kept in display cases, over many years' time, will show fading/warping/cracking issues on the side that received the most sunlight.
As mentioned, bone especially will crack pretty easily. It's very hard & rigid, and won't 'flex' as much as would be ideal for use on a pinned handle, where the pins move in response to stresses placed on them (such as with the anchor pin for the spring). And the drilled holes for the pins can introduce additional weakness, if the drilling itself starts a crack or chips the bone, or if the holes are drilled too close to the edges (too thin). I think a well-designed and constructed knife would allow for some movement of the pins within slightly oversized holes in the bone or, better yet, make sure the pins are sturdy enough and well-anchored in the liners, so they won't move at all. Some knife frames also flex or bend, as a whole, which can create stresses on the scales.