Frustrated "trying" to sharpen bench chisels

[Jeremy Gibson]

I have been working off and on trying to sharpen a new set of Marples Blue Chip bench chisels for about a month. Admittedly it has been more off than on, but today I gave it some more elbow grease. I have a piece of glass and sandpaper in 100, 150, 220, 300, 400, 600, 1500, and 2000 grits. At this point I am still working on flattening and polishing the backs.

The 3 smallest chisels are pretty good as of the 600 grit paper. Very shinny all the way to the front edge with a clear reflection. The 3 larger chisels are giving me grief. I either have a thin line at the front edge not getting flattened or a bit of the corner. What seem the most frustrating is how the scratches look even in the course grits and only show problems after getting to 400 or 600 grit.

I have to assume the answer is to keep going back to a course grit and work the back some more, but is there any advice out there in the creek? I have the glass on a piece of non-slip router mat, and then on a flat workbench surface. Is the mat a bad idea and should I mount it on a plywood base clamped to the bench?

[Michael Ballent]

What are you using to hold the chisel? I would ditch the router mat just because I would prefer anything not to move around on me. Have done the ink trick? You use a felt tip marker and "paint" the area that you are going to sharpen. Then as the metal wears away you will see any high/low spots. Other than that it's a pretty straight forward process.

[Don Baer]

I agree with Michael on this one. Loose the mat and use a magic marker. I sharpened my Marples in about 5 minute each using the scary sharp system. I happen to have a nice 12" square piece of marble that is 2" thick that I picked up at a leather craft shop so I use that instead of glass but I use the same regiment starting at 100 and working my way up to 2000.

[Travis Johnson]

Sounds to me like you are having the same problem I did when I first started the Scary Sharp method. You never mentioned whether or not you had a chisel holder or not. That might be the problem, an inconsistent bevel angle.

What I do is place my chisel in a holder, set the bevel and then start out with my lowest grit (in my case 220). After that, and without taking my chisel out of the holder, I flip it upside down and flatten the back/ take off the wire edge. I then go back and make a few stroked backwards only so that no burr forms. I then do that all the way up through my grits of paper (up to 2000) I then go an extra step further by stroping my chisels on a piece of leather charged with jewlers rouge, but that really is not nessassary.

I use a simple wooden jig to that registers my chisels at the same distance inside my chisel holder each time so I don't have to worry about changing my angles each time I sharpen a chisel.

As for my glass. I work for the railroad and found that locomotive winshields make the perfect glass for sharpening. They are 3/4 of an inch thick, laminated, heavy so they don't move around and are literally bullet proof, so I don't have to worry about a piece of glass breaking in my hands. Of course they are also free.

[Kevin Herber]

Jeremy, I feel for you. I am not a good sharpener either. I use the scary sharp method and have gotten 'fair to middlin' results. Questions I have are:

How big a piece of sand paper should we use? My piece of glass is 26 inches long and 5 inches wide.

What is the best sand paper and how do you attach it to the glass/granite?

How long of stroke do you use: 2-3 inches or the full length of an 11 inch sheet of paper?

How hard do you press the tool onto the sandpaper?

Do you lubricate the sandpaper? If so, with what?

Also, is the Veritas Mk.II honing gauge worth 50 bucks?

Thanks -- Kevin

[Ben Grunow]

On the job I sharpen my chisels with the belt sander (I can hear some of you cringing). Just take a firm grip and hold the edge against the wheel on the belt and apply gentle pressure until the edge is sharp and uniform. By this I mean that any dings and dents are removed and the cutting edge is square to the sides. This must be done carefully and slowly so as to not overheat the steel and cause it to lose its temper. After this process I will use a flat metal file to remove any burr that may have formed and then hone the leading edge and back with the diamond stone. Results are razor sharp. By that I mean that you can shave your skin or fingernail without applying any pressure. Scary sharp even. Sounds primitive but I have chisels that are 10 years old (and visibly shorter than when purchased) that I use every day and sharpen reularly. Someone always borrows them and chisels some concrete or a nail or something. Oh well, back to the belt sander.

[Jeremy Gibson]

Thanks everyone for the advise. I removed the router mat and noticed a significant difference. So far the glass hasn't shifted while honing, but I'll make a holder for it soon.

Travis, I have a chisel holder (grey clamp style until I buy the Veritas MKIIjig). The thing is I hadn't got to the bevel yet. I was still trying to flatten the back so no jig yet.

Kevin, from what I have read on the subject (as much as I can) I use wet/dry sandpaper if at all possible and sometimes use just a bit of water to lubricate. I have read about 50% that say to use it dry and do it sometimes. I try to take full length strokes, which can be 11" or 9" depending on the size of paper. The higher grits I got at an automotive store and are 9x4 sheets.

So now I worked the backs of all 6 chisels to 2000 grit and have started on the bevel. Thanks again to everyone!

[Michael Ballent]

Are you using the marker? That will really help you "see" what the cutting action is doing. Re-apply after every grit change

[Brian Hale]

I use a spray bottle with water and a few drops of Ivory dish washing soap.

Brian

[Lee Schierer]

Jeremy, I feel for you. I am not a good sharpener either. I use the scary sharp method and have gotten 'fair to middlin' results. Questions I have are:

How big a piece of sand paper should we use? My piece of glass is 26 inches long and 5 inches wide.

I use 1/2 sheets.

What is the best sand paper and how do you attach it to the glass/granite?
Aluminum oxide sandpaper from an automotive store. Garnet paper is almost a waste of time to use

How long of stroke do you use: 2-3 inches or the full length of an 11 inch sheet of paper?

I use full legth strokes. Stop to dust off the sheet every 8-10 strokes. Also wipe off the swarf from the tool with a dry soft cloth. Old tee shirts work well.

How hard do you press the tool onto the sandpaper?

I apply pretty firm pressure on the coarsegrits and slightly less pressure on teh finer grits.

Do you lubricate the sandpaper? If so, with what?

No. I sharpen dry. I also dust off the paper fairly often.

Also, is the Veritas Mk.II honing gauge worth 50 bucks?

I have trouble holding the angle steady by hand so I use the veritas sharpening jig. I think I paid $30 for mine, it is not their new deluxe unit.

Thanks -- Kevin

I hope these answers help. I use my hand tools much more now that I have learned how to get them sharp so they work well. It is a joy to see shavings coming out of a hand plane that are thin enough to read through. Good shavings should be about .001-.002" thick.

For you hand planes you will want to hone the sole as well. A mirror finish on the sole will make them slide easier.

[Kevin Herber]

Thanks guys. I'll try your suggestions and see what happens.

-- Kevin

[Pete Harbin]

My process is almost identical to Lee's. I use both sides of two pieces of glass. Two grits per side afixed with some 3M spray (77, I think.)

When I'm working on a particular grit, the sandpaper on the other side of the glass (face down) eliminates any movement.

Like Lee said, long smooth strokes, and brush the paper off after about 10 strokes. Don't wear a favorite T-shirt though...it will get a little grimey!
I also work the whole process dry. I did a full set of nine Marples Pro Touches, and then another "standard set" of 4 Pro Touches that I keep in my tool bag for any classes I take. (Taking Hand Tools in Santa Fe starting in August! Woo Hoo!) This system really works.

Pete

[tod evans]

jeremy, i`m a firm believer in no jigs. take the time to learn on what ya` got, oil or water stones, sandpaper-powered or flat, ect. it really doesn`t take all that long to develop a technique and once you do it`s like riding a bicycle. plus when you start acquiring carving chisels you`ll have half the battle whipped if you allready have a technique that works for you. .02 tod

[Travis Johnson]

Jeremy, I use WD-40 to flush the filings away, use automotive wet/ dry sandpaper and the same cheap gray jig that you mentioned.

[Maurice Metzger]

Jeremy, in my experience a lot of what you're going through seems standard for flattening the backs of chisels with sandpaper. It will seem flat on the rougher grits and then show non-flat spots when you move to finer grits. Moving back to the rougher grits is then called for.

If you have a belt sander there's advice here from Bob Smalser about using that to flatten the backs:

http://www.sawmillcreek.org/showthread.php?t=27953

I don't have a belt sander, I just spent the time with sandpaper and did get to flatness eventually. Later I used a 220 grit Norton diamond stone which was faster. I've worn that stone out so I'm about to try 3M 80 Micron Abrasive Film. If that doesn't work fast enough I guess I'll be getting another diamond stone.

Hang in there, it's all downhill once you get the backs flattened. A sharp chisel is truly a joy.

Maurice