[mikeg]

Hello all,

I've got a couple of sharpening questions. ???

The first actual carving knife I got was a Murphy knife. I thought it was plenty sharp at the time since I'd ordered it pre-sharpened and it went through basswood quite well. I've stropped it regularly with a leather strop and aluminum oxide. I recently got a Denny knife though and I realized the Murphy isn't as sharp as it could be. I looked at the blade and it isn't a flat bevel, it's convex. How would I sharpen that on a stone? Or should I even try?

My second question, is aluminum oxide a decent stropping material? I bought it and the strop when I got the knife. I realize that this is a loaded question since everyone has a different opinioin but I hear about a bunch of people using rouge, is that better? I did get a flexistrop that came with some yellow gold(?). Should I use that on the strop instead? Something different altogether?

thanks in advance,
mikeg

[AlArchie]

Mike, without knowing how your Murphy knife came originally, I'll still take a stab (pun) at your question. Â*It probably had a flat bevel on it to start with and the convex shape is due to stropping, maybe at too steep an angle.

If you have a decent sharpening stone, you should be able to correct the problem in a few minutes. Â*

First, you want to put a 10 to 15 degree angle on the bevel, on each side. Â*that will give you a 20 to 30 degree wedge on the cutting edge, which should be good for most of your carving. Â*An added 5 degrees will give a more durable edge, but will be a little harder to force through your cuts.

The proper angle on the stone can be achieved by imagining a dime placed under the back of the blade. Â*Learn to hold your knife at this angle when you sharpen on the stone. Â*

Second, try sharpening like you are trying to take a slice off the stone.....don't go in a circular fashion or drag the blade back. Â*The slicing style will form only a small wire edge,,,dragging the other way puts a larger burr on the blade that rtequires more stropping to remove.

Start with 20 strokes on one side of the blade, turn it over and do 19....then turn again and do 18, turn 17, turn16, etc till you get one stroke on each side of the blade. This will make sure you have an equally balanced bevel on each side of the blade. Â*further touch ups on the stone should only require a 10 stroke start!

Now you have to strop.....make sure that you hold the blade almost flat on the strop. Â*All you want to do is abrade off the wire edge and polish out those microscopic grooves from the stone. Â*Just strop and flip, strop and flip. Â*A sure way to elimnate the possibility of rounding your bevel is to flip the blade over the BACK instead of over the edge. Â*This seems a little awkward at first, but will totally eliminate the tendency to roll the edge as you turn the blade over.

Hope this helps.

Al

[AlArchie]

Oh, as far as your compound goes......most any compound will do the job well. I prefer a stick or paste base over just a dry powder, but sometimes use the white 'diamond' dust powder sprinkled on my strop charged with red rouge. Stropping compounds generally fall into abrasive size of .5 to 1.5 microns, so any one of them will give an excellently polished edge if used properly.

Al

[Hi_Ho_Sliver]

I got a tube of the white aluminum oxide compound with the burke sharpener I bought and didn't care for it because it turned everything black! But just for the heck of it, I tried it on a hand strop and it polishes better than most other things I have and no black? must be something about the power? Then I remembered....I posted awhile back about using a piece of cardboard or even paper for a strop and I remember it was the aluminum oxide I had put on the paper! I have a terrific memory....its just short!

[mikeg]

Al,

I've only had the Murphy knife since May. Would that be enough time to strop the blade convex since I'm a very part time carver? I think the second, larger, Murphy knife that I've got but rarely use is the same way but I'll have to check when I get home. I'm wondering if the company I bought them from rolled the blade as they were power sharpening it. I strop it by laying it flat on the leather since there was no clear bevel as with a Warren blade. Or put another way, the bevel was the width of the blade. I guess that's not true since the blade isn't flat.

Are there any good jigs out there for sharpening tools? I've heard that inconsistancy in the angle leads to secondary bevels which are a pain. I have a lanski system which is fine for the kitchen knives but it doesn't work on small blades nor do I imagine it would work with a gouge or v-tool.

mikeg

[AlArchie]

Mike, the jigs available work well for flat chisles and there are Oar jigs for gouges. I think most carvers will agree that for sharpening a bench/detail/pocket/hunting/other KNIFE, developing a good technique for hand sharpening is the best answer. Your final bevel should be around 1/16' wide and no more than 3/32', if that's any help.

There are small plastic sharpening jigs with two crossed ceramic rods that do work quite well. Fiskars makes one but there are several other brands available that work quite wll. You'l find these in the hunting and fishing departments of K-Mart, WallMart, True Value and I think I've seen them in Ace Hardware stores.

I purchased 50 or so Murphy knives for our Scout Camp from Rick at Little Shavers, and they came sharpened to a super keen edge. Without watching your stropping technique it's impossible to say if you could have rolled that edge to the condition you describe, but it's unlikely.

A lot of very good knives come from the factory only roughly sharpened or in need of edge development before they are truly sharp. That may be the case with your Murphys. Try my instructions for resharpening and if that works, your technique is properly developed. Practice is the only thing that will give you the consitantly razor sharp edge that you want. Or try those crossed rod sharpeners. they really do work.

Al

I put much of what I know about sharpening on my website if you would be interested in reading it.
It could answer some of your questions.
www.littleshavers.com
Rick

As far as rounding the Murphy in 4-1/2 months, the answer is yes, it could happen.
The Denny has a thinner blade and longer flat grind than the Murphy so it will normally feel sharper when new.

Denny is a very good line of knives, but don't discount the Murphy, I still use a Murphy knife daily; it was one of my first carving knives and it is now my 'fine detail knife'.

[mikeg]

Rick,

Actually when Al mentioned you, I went to your site to see if your catalog was on-line yet. I saw the link to your sharpening wisdom and read it while I was there. It has some good info.

I don't plan to ditch the Murphy knife, just want to get it good and sharp again. The Denny knife definitely has a thinner blade since it's a 3/4' detail blade. Once I get it back up to speed the Murphy will be my general purpose knife again.

Al,

The Murphy was supposedly sharpened by the retailer when I'd purchased it and it was much sharper than the pocket knives I'd been using before that.

thanks again,
mikeg

[mikeg]

Rick (or anyone else who can answer)

I was looking at a Wood Carvers Suppy catalog last night and it clicked what Rick meant on his site about single and double bevels on knife blades.

That prompted a question. With my Denny knife, it has one bevel the width of the blade. According to Rick's site, that makes sense. My Murphy knives look like they may have been manufactured with two bevels but when it was power sharpened, the line between the bevels was rounded. Again, I suppose 2 bevels could make sense on those blades. So I guess I'll work on the edge's bevel. Now, after all that, my question. Do you folks have one or two bevels on your pocket knives? Or do you use both depending on the size of the blade? Actually, a second question, do you generally round the transition between the bevels as I've described on my Murphy knives?

thanks,
mikeg

The answer to your question is - Yes! I round everything off, the transition between the bevels and also the back edges of the blade. I have pocket knives with one bevel and I have pocket knives with two bevels. There are two schools of thought on pocket knives. One is to sharpen it with the back of the blade elevated slightly (two bevels) and one is to hold the blade flat on the stone (one bevel). Both work. The two bevel option is best for all around use and use on harder woods. While the one bevel method is best for softer woods such as basswoods. That's why I always carry at least two. If you really want to go nuts, think about the effect that the width and thickness of the blade has on the angle of the bevels. We can make this entirely too complicated if we really try. We tend to lose sight of the whole object which is just to end up with a good carving knife.