Sharpening framing chisels.

Squirrell_Boy · October 07, 2003, 07:48:12 PM

Just wondering what you guys use to keep those big framing chisels sharp. I know the Makita wet grinder works good and the Tormek is great, but they are pretty expensive.
Wondered if you guys have any tricks or tips in this area. Nothing beats a razor sharp chisel and i want to keep mine sharp.

Jim_Rogers · October 08, 2003, 05:50:09 AM

I use a DMT Diamond Sharpening System with a Veritas precision honing guide.
The diamond stone uses water to create a slurry of liquid to lube the stone.
The honing guide holds the chisels at the correct angle to sharpen them.
I have several different grit stones, coarse and fine. If you have a big nick in the chisel start with the coarse and then move to the fine. After the fine you hone with a leather strap and some stropping compound.
Before I met my friend the blacksmith who has taught me the stropping method, I took a course at a tool store where I learned how to use the stones. That is if you can call them stones they are plastic block with a diamond strip attached to it.
I've found these diamond stone works good.
You should try and find some one to teach you how to sharpen your chisels. Once you've got them very sharp it doesn't take much to keep them that way.
Good luck, Jim

Noble_Ma · October 08, 2003, 06:23:04 AM

I use Arkansas stones with a light oil. I start with a soft stone. Finish with a fine (white) and extra fine (black). I bought them at danswhetstone.com. Good prices, free shipping and free bottle of oil.

ohsoloco · October 08, 2003, 10:47:07 AM

I use a soft and hard Arkansas stone, which are coarse and fine oil stones, respectively. I like to have a "hollow", or concave surface on the bevel, and I rough this out with the bench grinder, being careful not to heat the tip up. Once the hollow is established, I run it over the soft stone..it usually doesn't take more than a minute to create a nice burr on the back of the bevel. I then hone it out on the hard Arkansas. I can sharpen with just the stones quite a few times before I have to hollow out the bevel again. If you grind it at the right angle, I don't think a bevel gauge is necessary on such a large chisel...I just set the bevel of the chisel right on the stone so the front and back edge are being sharpened.

Don P · October 08, 2003, 04:32:18 PM

I use the same method as ohso pretty much. I have a soft friable white grinding wheel on the bench grinder and a nice little tool rest made by veritas (I think) in front of the wheel that is very adjustable. I took the stock tool rest off. A light touch and a can of water to avoid burning. Then I do the diamond stone, then on the other side of the grinder is a muslin wheel charged with emory that I "strop" on quickly. I've used rouge and a hard felt wheel for this before also.

Off the subject, do any of you have pics of a homebrew planer knife sharpening rig for 15" blades?

ohsoloco · October 08, 2003, 05:25:37 PM

Don, I made a pretty rough jig for sharpening planer blades, but I don't have any pictures :-/ I sort of "hone" the knives with this jig, but I don't know if a back-and-forth or circular motion on knives really does a good job. A friend of mine just bought a Grizzly sharpener for his planer knives for $170, he seems real impressed with it...I may have to pick one of them up.

Don P · October 09, 2003, 05:31:42 AM

Thanks I'll look into it, wouldn't take too many sharps to pay for that.

Jim_Rogers · October 09, 2003, 06:40:38 AM

When using chisels and a bench grinder be very careful. Most bench grinders turn too fast to be used to sharpen chisels. They do make a slow speed grinder for sharpening.

I would also like some info on the planer knife sharpener.
Jim

Greg · October 09, 2003, 08:55:27 AM

QuoteWhen using chisels and a bench grinder be very careful. Most bench grinders turn too fast to be used to sharpen chisels. They do make a slow speed grinder for sharpening.

I would also like some info on the planer knife sharpener.
Jim

Fast is part of the equation.

But the material in the wheel has a lot to do with overheating the metal. White (fancy name eludes me) grinding wheels are more suited to bench grinding of chisels

A buddy of mine does ALL his sharpening on a grinder and gets excellent results this way, in about 1/10th the time. MUCH fast than screwing with stones, slicks and the whole nine yards...

Planes are a different animal, I'm not too familar with.

Greg

ohsoloco · October 09, 2003, 11:25:46 AM

Here is a link to Grizzly's planer knife sharpener:

http://www.grizzly.com/products/item.cfm?itemnumber=G2790&gid=341043E5-5310-4878-8F63-93593011D33C&site=grizzly

I don't have the capabilities to post any pics of my home made one right now :-/

Don P · October 09, 2003, 01:49:14 PM

I kinda came into sharpening backwards. I worked for a little company that was getting into producing and reproducing custom mouldings. Our wants were automatic sharpening equipment but the budget was a dayton bench grinder and a slew of different rocks. The same rules apply there, burn the metal and it drops out pretty quick, so you learn fast how to work lightly and cool but efficiently. I would work with 3 knives at a time, 2 in the bucket and one being ground. We were just doing what we had to to make things work. I also kept the cabinetmakers chisels sharp. I like to work with a few chisels at the same time for the same reason.

When you have a hollow grind there are 2 points to later ride the stone, its easy to ride the chisel flat on those "lands" without rocking. As they merge upon successive honings on the diamond stone and muslin wheel, its time to go hollow it out again, or when you find steel :(.
I find if you can sharpen fast you are more likely to sharpen often. The charged wheels are part of that, a very fast strop. I can't remember the fancy name for that wheel either, it does cut cooler, wears fast, exposing fresh unloaded grit easily.

Don P · October 09, 2003, 03:57:07 PM

Found the fancy name...aluminum oxide :D
Heres the wheel I've been using and description of a couple of others for similar use.
http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=105-677

Here's the felt wheels and compound
http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=815-825

jeepman · October 09, 2003, 07:47:40 PM

Could anyone tell what angle you normally sharpen to? I'm new to timber framing and all I know is metal working (drill bits, tool steel for lathe, etc). Thanks in advance for any help.

ohsoloco · October 09, 2003, 07:49:52 PM

I think it's around 25 degrees :-/

ARKANSAWYER · October 10, 2003, 06:47:09 AM

I send my chisels down the road to a guy who sharpens things for a living. But when they get home I go over to a friends who has a cardboard wheel on a grinder that he got form Grizzly and you can put a compound on there like 6000 grit. It will strop it smooth as a mirror and very sharp. The cardboard wheel does not get hot. I touch up with Arkansas stones on the job site and have several files in my box. If you get it right on a good steel chisel they will shave the hair off your arm after several hours use. Becareful with them grinders as you can sure ruin a good tool quick.
ARKANSAWYER

Jim_Rogers · October 10, 2003, 08:05:40 AM

About the angles for sharpening chisels, my books say 30° for softwoods and 35° for hardwoods.
My sharpening system allows me to set my bevel at either of these settings and then turn the wheel to advance 1° for a micro bevel on the very edge of the blade.
Make sure your back side is flat at the tip all the way across.
My books say 25° is for plane irons, but I could be wrong. It depends on who you listen to.
Good luck, with your sharpening. Jim