Reply
Member
rbaker3577
Posts: 20
Registered: ‎11-09-2009
0

Angle to Grind Wood Chisels

I understand that the "standard" for grinding wood chisel bevels is about 25%.  I have been grinding mine at much more than that.  I have an 8 in. white grinding wheel.  If I set the tool rest at 25%, will I get a 25% bevel on the chisels, or does the arc of the grinding wheel have to be taken into account?

Honored Advisor
mathisonr1
Posts: 4,049
Registered: ‎11-07-2009
0

Re: Angle to Grind Wood Chisels

No you do not make any adjustments for the diameter of the grinding wheel. What you will be achieving is called a hollow grind. You can achieve a razor sharp edge on a hollow ground chisel faster than on a flat ground chisel. A hollow ground chisel also dulls faster.

Rick Mathison
General Forums Host
"I believe that to have a friend, a man must be one."
Senior Advisor
wirebender
Posts: 2,097
Registered: ‎10-23-2009
0

Re: Angle to Grind Wood Chisels

Russell -

 

Chisels get different bevel angles for different tasks: 25° or lower for paring, 30° or so for chopping.

 

Dave.

There's gotta be a better way
Veteran Contributor
TheDude50
Posts: 120
Registered: ‎07-06-2011
0

Re: Angle to Grind Wood Chisels

[ Edited ]

The normal way grinder chisel is not on the round part of the wheel but on the side of the wheel. Hold the chisel to approximately 25°After that you can put a second bevel on the tip of the chisel that is approximately 30° usually ID the 30° portion on my MPower PS S diamond: hone. This tool cost around $80 and does a marvelous job of honing your chisels to a razor-sharp edge that you can literally shave with there are several retailers that sell this product but my favorite is the Japan woodworker. I found that Hollow grinding chisels as you have been doing makes the tip very weak and thus are prone to breaking.Granted there are 1 million ways to sharpen your chisels the way I am recommending will provide you with a razor-sharp edge and is very safe the PS S by MPower is a foolproof way to put a great edge on your chisels even if you are a novice sharpeningI hope this helps sincerely Lance granumthe dude 50 formerly the dude

The stupidity of your actions is directly proportional to the probability of someone watching you.

proud member since 1995
Honored Advisor
JL North GA
Posts: 1,621
Registered: ‎10-23-2009
0

Re: Angle to Grind Wood Chisels

[ Edited ]

With standard grinding wheels and 8" or 6" grinders - do NOT use the side of the wheels.   This is NOT a safe practice.  Yes, you can get away with it for a while but it is not recommended.

 

From Nortons safety poster.  Side pressure on thin straight wheels is dangerous.  Most wheels will stand quite a lot of straight radial pressure, but there is a limit to what they can take.   Heavy pressure with vitrified wheels is apt to cause the wheel to get hot.  If it gets too hot too quickly, it  is apt to break.
Sudden bumping or pounding is  more dangerous than steady, even pressure.  All bench and pedestal wheels must be dressed to prevent loading. Loading can cause excessive heat, damage to the workpiece, and wheel breakage. Dressing exposes new cutting edges and provides chip clearance.



 

The answer to your question as others have said - it depends on what you are doing and what the wood happens to be.  My softwood chisels are set at a lower angle (25 degrees or so) than my hardwood chisels (30 degrees or so).  You are putting a hollow grind on your chisels. 

 

Typicaly, I put a hollow grind on my chisels.  I then switch over to my waterstones to hone the chisels.  When they get dull, I just give them a few strokes.   The top and the bottom of the bevel are the only thing that gets honed or sharpened then.  After the chisels lose the hollow, they go back to the grinding wheel.  If you do it that way, you can use waterstones, oil stones, sandpaper or whatever to hone the chisels.

Honored Advisor
johnclucas
Posts: 1,980
Registered: ‎10-26-2009
0

Re: Angle to Grind Wood Chisels

I agree with JL.  using the side of the wheel is dangerous.  I know we have all gotten away with it but it's one of those things that only takes once to ruin your day.   

     My hand chisels are ground to 25 degrees.  any chisel that will be used with a mallet is ground to 35.   I personally don't believe a hollow grind makes a chisel dull faster.   You still have the same angle for 1/16" or so if you hone the edge with a diamond hone.   Now if you use a mallet a hollow grind might be weaker but I generally use an 8" wheel so the hollow grind is just thousandsths of an inch less metal than a flat grind.

Veteran Contributor
TheDude50
Posts: 120
Registered: ‎07-06-2011
0

Re: Angle to Grind Wood Chisels

:smileyvery-happy:JL North GA I have been using this practice for over 30 years it is safe because it requires very little pressure as you can see in this video http://www.ehow.com/video_4418697_sharpening-marples-wood-chisel.html you would never put huge amounts of pressure on the side of the wheel is a very light touch process takes very little pressure you actually just make contact with it this is not like grinding off a piece of ride and rounding it or something like that is a very slight pressure and a very delicate angle all you do is lightly touched the chisel as shown in this video once the edges there I still recommend that MPower PS S because it is fixed at 25 and 30° anyone can use this tool and get good results.http://www.youtube.com/watch?v=p8NrP0Zub0U&feature=player_embedded a I prefer this method because it works very well you don't get your chisels hot from grinding them on the wheel face as you can see my method works is safe and give you a good tool that is also safe and works well try my method and let me know if you think the results are satisfactory if you use all the steps I've outlined and shown you in the to videos you will be please with your chisels be sure to go through several grades of DS as stones to achieve the ultimate polished chisel these will be chisels you will be proud to let anyone borrow because you know they're safe the method is easily repeatable and produces a high-quality finish I do hope this helps you I hope this puts any concerns of safety to rest sincerely Lance granum the dude 50 formerly the dude

The stupidity of your actions is directly proportional to the probability of someone watching you.

proud member since 1995

 

© Copyright 2009, Meredith Corporation. All Rights Reserved | Privacy Policy | By using this site, you agree to our Terms of Service.