I need some grinding help...

MeDoctor

MeDoctor

Joined
Dec 8, 2003
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This blade is my first try at flat grinding, and I can't seem to get the transition from the plunge on the side in the first photo to taper up toward the spine like the side in the second photo. Any suggestions?

Thanks,

Mark
 

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Just looking at the photo it looks like the grind is higher on the 1st pic than it is in the second pic. Two ways to fix it... Grind the second side higher to match the higher(1st pic) side. or place the 1st side completely flat against the platen and grind the entire knife slightly thinner, this will bring the grind line down.. Be careful though or you can end up chasing those grinds around until nothing is left of your knife..good luck..as usuall your milage may vary.. others may have different options for you...
 
Personally I'd even them up with a file -harder to screw up that way. ;)

And then when you sand and buff the knife you'll never be able to tell the difference.
 
rocketmann said:
... place the 1st side completely flat against the platen and grind the entire knife slightly thinner, this will bring the grind line down...
Click to expand...

I've done that -- twice -- and the resulting grind line goes the wrong way - that is, it's thinner near the plunge and thickens as it goes toward the tip. I can't seem to make it taper the right way.

Thanks for the reply,
Mark
 
Go to the paint store and get soeme stiring sticks, practice on them til you get comfortable enough to try on metal.

takes alot of practice to get right.
 
Destichado said:
Personally I'd even them up with a file -harder to screw up that way. ;)

And then when you sand and buff the knife you'll never be able to tell the difference.
Click to expand...

I would, but it's already been hardened. It'd be slow work with a file.

Mark
 
At some point you have to say "this is the best that I can do at this stage" and move on and finish the knife to the best of your abilities. Later as you progress you can look back at that knife and realise that things that were really hard then now come as second nature.. It is a never ending cycle, always learning always progressing....Good luck in you journey..
 
Hmm. I still think I'd just normalize it, fix it and reharden. But off the top of my head I can think of a few more options.

You could try differentially tempering the knife so the spine is softer, then use the file more quickly. An old blacksmith's trick is to heat a large bar or plate to red heat, set the spine of the knife against it and watch the colors march up the blade. In this case you'd want the spine as peacock as you can get it without messing up the edge, and your knife is small enough that you don't have much leeway, so I'd run an ice cube across the cutting edge as I did it.

You could try grinding it out on a stone, too. I once took a spent wheel from a bench grinder, set it in a pan and used it as an oilstone. Worked great! Very aggressive for a stone, and of course it doesn't slide off of hardened steel either.

Or you could just practice to learn finer control on your bad side. ;)
 
rocketmann said:
At some point you have to say "this is the best that I can do at this stage" and move on and finish the knife to the best of your abilities. Later as you progress you can look back at that knife and realise that things that were really hard then now come as second nature.. It is a never ending cycle, always learning always progressing....Good luck in you journey..
Click to expand...

Perfectionism. It's one of my strengths AND one of my biggest weaknesses.
 
Mark - I think I know what you're asking here, but please forgive me if I'm wrong. It looks like the second picture with the lower grind has more of an acute angle at the top of the grind than the first picture. Is your grind coming out too "straight" on the one side and angled on the second? From these photos I don't see anything wrong with the plunges, but it's hard to tell.

If it's the grind at the top then the only way I know how to even it out is to tilt the knife. What I think you're doing is following the tip on one side and grinding straight across on the other side. You may also be leaning on one side or giving more pressure on the outside of the knife. If you want to fix this knife then I suggest standing in front of the grinder and "mock" grinding with the blade trying to see how you work differently on each side, study the angle of your grind transition and then try to repeat it on the other side.

Something that I was taught is that you should figure out which side is your weakest and always grind that side first. It's much easier to match a grind with your strong hand than it is to fix a grind with your weak one.
 
From what I get you are trying to grind a distal taper. You can try this it may help you get the desired result. Flat grinding (edge up) With little to no pressure start in the middle of the blade, move the blade to the plunge (this helps to set the angle) apply pressure and grind to the point.the blade should be 90% horizonal to the belt(like a line from left to right across the belt.As you get to the curve of the blade to the point keep the same angle and roll the handle down. This should geve you an even edge width from plunge to point. I hope this makes sense. I could show you in half the time it took to type this.Of course I type real slow
 
Sorry, After restudying the pics Have to agree with Cap ( Acrid saint) Looks like an angle concern. Practice, Practice ,Practice. By the way nice look'in little knife.
 
I was having this same problem and here's what I did to fix it. I looked at my belt going over my platen. My platen was not parrallel on the edges with the belt. What I mean is on the left side of the platen at the top the belt would not be handing over the edge but the belt angled down and was handing off the edge of the platen on the bottom left side. On the right side it was opposite. The top right was hanging over, but on the bottom right the belt was not. Hope that made sense. I had to shim my platen a hair to line it all up. It cured my problem.
 
Ryan Minchew said:
I was having this same problem and here's what I did to fix it. I looked at my belt going over my platen. My platen was not parrallel on the edges with the belt. What I mean is on the left side of the platen at the top the belt would not be handing over the edge but the belt angled down and was handing off the edge of the platen on the bottom left side. On the right side it was opposite. The top right was hanging over, but on the bottom right the belt was not. Hope that made sense. I had to shim my platen a hair to line it all up. It cured my problem.
Click to expand...

Thanks Ryan. Mine was a bit out of whack in the same manner. I'll see if straightening it out helps. I've been using a pyro-ceramic platen liner, but I have another platen set up with a soft graphite liner. Might the softer platen be more forgiving?
 
MeDoctor said:
Thanks Ryan. Mine was a bit out of whack in the same manner. I'll see if straightening it out helps. I've been using a pyro-ceramic platen liner, but I have another platen set up with a soft graphite liner. Might the softer platen be more forgiving?
Click to expand...

I've used the soft graphite platen liners as well as the ceramic liners. I'll tell you that it is much easier to feel your bevel (kind of like feeling the groove on a hollow grind) with the harder ceramic platen. The graphite platens do run a bit softer, but after a few blades, they will develop a groove across them where you tend to grind heavier or in the area you use the most. My grinds got better just by switching to the ceramic. Just use light pressure as you're learning so things are easier to feel. I say that with the caution that if you are just using feather light pressure, you'll probably not be able to feel your bevel angles and goof up. So light-medium pressure works well. Also, if you're having problems with belt bump, make sure you're using a good name brand belt.

--nathan
 
AcridSaint said:
...What I think you're doing is following the tip on one side and grinding straight across on the other side. You may also be leaning on one side or giving more pressure on the outside of the knife. If you want to fix this knife then I suggest standing in front of the grinder and "mock" grinding with the blade trying to see how you work differently on each side, study the angle of your grind transition and then try to repeat it on the other side.

Something that I was taught is that you should figure out which side is your weakest and always grind that side first. It's much easier to match a grind with your strong hand than it is to fix a grind with your weak one.
Click to expand...

Thanks. I know I take a slightly different stance when I go from one side to the other (I tend to stand more to the right side of the grinder when working the right side of the blade). Would it help to focus on staying centered over the belt?
 
I think everyone changes stance from side to side and that being comfortable trumps mirroring position from side to side. The key here is to recognize the differences and how they change your grinding angle. I would focus on keeping the knife on the same plane for both sides. If you follow the grind of the tip (perfectly acceptable to do) then follow it first with your weak hand so that you can easily mimic the motion with your strong one.

Feel free to make very small corrections and then check your work, I still check my grinds dozens of times and I'm more confident in my grinding now than ever before. Also, if things are moving too quickly for you, switch to a finer belt so you can remove less material. Just be aware that a very sharp fine grit belt seems quite aggressive initially.

I'm no expert, just a regular guy who's still learning. These are all things that were taught to me and I'm probably leaving some out. Hope it helps.
 
MeDoctor said:
Thanks Ryan. Mine was a bit out of whack in the same manner. I'll see if straightening it out helps. I've been using a pyro-ceramic platen liner, but I have another platen set up with a soft graphite liner. Might the softer platen be more forgiving?
Click to expand...


No prob. I'd be interested in seeing if it fixed the problem, or if it's a combination of stance and being off. Mine instantly went away, but I can get the same thing again if I'm not paying attention. I've never tried the soft graphite liner, but from what I've read it sounds like it is too soft for me to try and grind on.

Also looks like I need to pay more attention typing, handing? Is that even a word?lol
 
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