Dull dull delica

B

Brad Greulich

Joined
Feb 4, 2006
Messages
739
I carry a delica 4 everyday to work and it just wont stay sharp.

I work as a CNC machinest and only have to cut a bit of card board, tape, and the blade sometimes runs along a bit of plastic. Nothing that VG10 cant handle. The problem I think, is that everytime i pull it out of my pocket the balde is covered in really small steel chips and i think they might be wearing down the edge. (Im good at sharpning before you make fun:p, and it could shave a few days ago, now it cant and i'v only used it to cut off some tape).

I'v had the knife for about 2 years, is it possiable the balde lost it's temper somehow? possiably from sharpning, as i used to use it all the time.

Any help would be great.
 
Did you sharpen it with an electric grinder, belt sander or other powered equipment? If so it is possible that you heated the temper out of it.

It may be that you just have a very tough environment there. Cardboard is notorious for dulling knives. If it is dirty, it is even worse. Maybe the other stuff you cut also has grit or metal shavings on it from the machining activity. One possibility is to give up on using a knife in that environment and use a folding box cutter instead. You can even resharpen the box cutter blades very easily because they are so thin. Or just swap the blades.

You could also get one of the quick and dirty sharpening devices like the Edgemaker Pro that will restore the edge with just a swipe or two through the slot. 10 seconds a day and never a dull blade.

Good luck.
 
You make some good points, but i sharpen it with a Lansky C clamp set, so nothing hot, just stones and oil.

I have a hard time bringing my self to using a box cutter, considering the money i'v spent on 'real' knives :P
 
I,ve got an Endura that went that route but it held up a good couple of years before the edge was shot.
 
If it's covered in steel chips, maybe it's magnetized? Do you have access to a demagnitizer? Not sure that would fix the problem, though.
 
It may just need honing rather than sharping. Try taking a small piece of 600 grit sandpaper and squeeze it over the edge and pull the knife through, as though you want to polish the sides of the edge.
 
Brad Greulich said:
.... it could shave a few days ago, now it cant and i'v only used it to cut off some tape.
Click to expand...
That sounds like a wire edge, they can be quite sharp but won't hold up. I would try sharpening again, making sure to clean up the wire edge before you go to your finish step/highest grit. For tips/techniques for removing wire edges, see: http://www.bladeforums.com/forums/showthread.php?t=355227

It also sounds like the blade is magnetized, which shouldn't hurt anything except for the annoyance of attracting steel particles. You can easily demagnetize it with a soldering gun, just stick the blade within the "loop" of the soldering tip, turn the gun on, and slowly remove the blade from the loop.
 
Not very often, but sometimes a bad heat treat slips through. Send it back to Spyderco, and they will hardness test it. If it specs out, they will sharpen it for small fee, ($5 bucks I think) and if it doesn't meet spec, they will replace it.

good luck
 
Brad Greulich said:
I'v had the knife for about 2 years, is it possiable the balde lost it's temper somehow? possiably from sharpning, as i used to use it all the time.

Any help would be great.
Click to expand...
Lost it's temper? Have you used it in a hostile environment? Do you use any type of magnification during sharpening? Is the entire edge giving you trouble or just one/some areas? Try starting with some new steel by taking the knife and cutting right into a good coarse stone. This will get rid of any weak crumbling steel. Then resharpen.
 
My s30v can get plenty dull in a day doing exactly as you describe. Falling a couple skids of boxes and cable ties etc.

Even though it won't shave, my knife stay usablly sharp until the next sharpening, up to a month sometimes.
 
A shaving sharp edge on good steel that easily/quickly dulls is probably a wire edge like Dog of War said. The edge is bending/folding over when a little stress is applied. Put a solid edge on the blade and try again.
 
Brad Greulich said:
I carry a delica 4 everyday to work and it just wont stay sharp.

I work as a CNC machinest and only have to cut a bit of card board, tape, and the blade sometimes runs along a bit of plastic. Nothing that VG10 cant handle. The problem I think, is that everytime i pull it out of my pocket the balde is covered in really small steel chips and i think they might be wearing down the edge. (Im good at sharpning before you make fun, and it could shave a few days ago, now it cant and i'v only used it to cut off some tape).

I'v had the knife for about 2 years, is it possiable the balde lost it's temper somehow? possiably from sharpning, as i used to use it all the time.

Any help would be great.
Click to expand...

It could only lose its temper if heated above 350F for a number of hours. A Lansky would have no effect on the temper. The chips would only affect the blade if they impacted it. Just cliniging to it should not do anything. I'm assuming you wipe them off before cutting.

I think Dog of War has the answer.
 
It could be one of 2 issues:

1. The angle of the grind is too broad. So it gets sharp but then loses the edge quick.

2. The angle of the grind is so thin that the burr just flops over. So it appears sharp at first but dulls really quick. It is thin but not strong.

If it is issue one, it is easy to fix, just sharpen thinner. You need to remove metal. Use a coarse stone and take off some of the edge at a lower angle than previously done.

I am pretty sure it is problem 1, because you sharpened it for 2 years with the same shaprener and never adjusted for wear on edge. That would slowly broaden the grind which would make it not hold an edge for long because there is no edge left.
 
Hi Brad,

Sorry you are having a problem with one of our knives. Our rate of consistency is quite high, but anomalies are always possible.

While there are many good suggestions made here, diagnosis is quite difficult without looking at and testing the knife. Comparing the edge to a new model might reveal some information.

I would suggest that you send it back to Spyderco.

We can inspect the edge under magnification, Rockwell the blade, check the edge angle on a goniometer, measure the thickness, etc.

then we can fix it or if it's an error on our part, we can replace it.

sal
 
Wow, that's service. I only have one Spyderco, an Endura in VG-10. I haven't used it enough yet to determine how good the edge holding is, but it came very sharp from the factory. It is sure nice to know that Spyderco stands by their products. Maybe the serrated edge would hold up better for cutting cardboard?
 
sal's numerous posts are another of the many reasons why spyderco is my number one choice for folders.
 
Thanks a lot everyone.
Dog of war- thanks for the advice, I’ll sharpen it and make sure to remove the wire edge this time.

And Psy-Ops, I'm not sure I know what you mean in regards to your first point. If I always sharpen it to 20 degrees, what would cause the grind to broaden? And wouldn’t re-sharpening it with eg. a 17 degree angle make the edge to fine to stay sharp for any decent amount of time?

Thanks for the help tho
 
Sal Glesser said:
Hi Brad,

Sorry you are having a problem with one of our knives. Our rate of consistency is quite high, but anomalies are always possible.

While there are many good suggestions made here, diagnosis is quite difficult without looking at and testing the knife. Comparing the edge to a new model might reveal some information.

I would suggest that you send it back to Spyderco.

We can inspect the edge under magnification, Rockwell the blade, check the edge angle on a goniometer, measure the thickness, etc.

then we can fix it or if it's an error on our part, we can replace it.

sal
Click to expand...


Thanks alot Sal,

If I cant fix the problem on my own, it will be heading back soon.:thumbup:
 
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