need some sharpening help!!!

[Vanilla Gorilla]

I use the scary sharp method of sharpening, and although I am getting decent results, I am far from splitting hairs. Admittedly, I am not using very good chisels, but I still feel that I am doing something wrong. I use a thick piece of glass, and spray glue strips of sandpaper in grits from 120 to 2000. I also use a veritas honing jig. My big questions are these:

when sharpening, do you only push the chisels, only pull them, or do some sort of combination of the 2?

should you go through all the grades with the back of the chisel before honing the bevel, or lap the back on one grade then do the bevel on that same grade, then move up to the next grit?

I have read a ton of things on the net about sharpening, but none of them have addressed these (simple) questions. Also, I have never seen a burr form on the edge of the chisel, so that's probably good evidence that I am doing something wrong. Any info would help!

 

[jglord]

A couple of points in addition to what Mike has already said.

First - In my experience, sand paper wears-out very quickly and wonder your glueing the paper to the glass causes you to use the paper beyound its useful life. I have good luck using a spray bottle to wet the surface, then using same to wet the paper after sticking it down. A trick I saw on the David Charlesworth videos (from Lie-Nielsen) is to "break the back of the paper" by drawing the back of the paper over a 90 degree edge. Bending the paper backwards over a sharp edge reduces the tendency for wet/dry paper to curl.

Second - I too use a Veritas jig. I find it works out to flatten the back first by working through the grits, the higher the polish, the better. Then put the tool in the jig and check for proper alignment by looking at the pattern after a few strokes. If the blade is properly aligned, the pattern should be symetrical. I've found it to be easy to have a slight alignment problem. Once I'm satisfied with positioning of the blade in the jig, I don't remove the jig until I'm done sharpening. To remove the wire from the back, you can turn over the blade, in the jig, and take a few strokes on the same grit, being very careful to keep the blade flat.

Third - on going in both directions vs. pulling only. I'm not sure but, referring to David Charlesworth again, he says to pull only. I have been going back and forth. I guess this is a question for others.

Fourth - Watching an expert in person is a great way to learn, if you can not watch one, then a video of an expert is a great way to learn, and get answers to your very important questions.

 

[wapitiscat]

Make sure you chisel back is flatter than flat (at least the first inch or so from the tip). Once the back is flat, I get a decent "edge" even before honing the old bevel. Also, make sure your chisel tip isn't to dinged up. After enough use and abuse, I will essentially start over by grinding the tip square (not by much ... maybe 1/16" or less) to get back to a consistent part of the blade. Then, regrind your primary bevel on the wheel or a coarse diamond plate. As you work up through the grits, check to make sure you're getting the wire burr. If not, then you may check to make sure the chisel isn't moving in the jig. Also, once the blade is in the jig, keep it there until you're done with you finest grit. Good luck.

 

[Phillip]

hi, just my two cents, i find it difficult to get adequate pressure on the bevel on the pull stroke so i only push. and i polish the back through all the grades before moving on to the bevel, and only using the finest grit on the back from there on to remove the burr.

phillip

 

[wapitiscat]

Just a followup to my first reply ... I think you want the entire chisel back flat. I was thinking gmore about plane baldes. With chisels, you will want the entire length flat for paring type operations. I think this is the way to go but you may want to check some more if you're faced with a lot time at the lapping plate.

 

[DavidF]

Just a followup to my first reply ... I think you want the entire chisel back flat. I was thinking gmore about plane baldes. With chisels, you will want the entire length flat for paring type operations. I think this is the way to go but you may want to check some more if you're faced with a lot time at the lapping plate.

You really only need to get the front area just behind the bevel polished to a shine; the rest of the back can be flat, but not polished so just get that to an even scratch pattern using a fairly coarse stone. Then move to increasingly finer stones or paper to put as close to a mirror shine on the first half inch. Only then move to the bevel side and do as everyone has suggested. Raise a burr on a medium stone then without touching the back of the chisel, move to finer and finer grits until the bevel is also polished. If you go fine enough the burr will just fall off, but generally once you get to the same grit that you finally polished the back with, just do alternate LIGHT stokes on the bevel and back until you feel and see no burr. Hold a strong raking light across the edge - if you can "see" the edge it isn't sharp. You can do a final lap with a strop but unless you are experienced it is easy to round over you newly made edge! Subsequent sharpenings do not include the back at all. If you can't raise the initial burr or only on part of the edge then your stone probably isn't flat.

 

[junquecol]

If you can't see you reflection on back, then it ain't flat enough. The microscopic scratches on back also occur at edge, creating a pinking shear effect. Get some Tormek polishing paste and use on a piece of MDF. You might want to add a drop of oil to MDF before adding polishing paste. Do I use a jig- no, but I rub chisel side to side, instead of back and forth. Usually in about thiry minutes, I can take a "junk" chisel to sharp enough to remove hair on fore arm sharp.

 

[DavidF]

"You really only need to get the front area just behind the bevel polished to a shine; the rest of the back can be flat, but not polished so just get that to an even scratch pattern using a fairly coarse stone."

When I said the above I was talking about the "back" of the chisel, what Junquelcol says is correct, but not required over the whole of the back of the blade just the first 1/2"