Replies

1. 
   Troy | Jan 16, 2006 07:36am | #1

   I have had simmilar problems with Marples chisels. If you have not overheated the blades you sould be ok. I had not heard about leaving the water out over night though.

2. 
   philip | Jan 16, 2006 10:05am | #2

   Rod, if you can still hold the end of a chisel after grinding then there is no question of over heating. Dipping in water at those sort of temperatures , oxygenated or not, will cause no problem .The neighbour is right enough about leaving the micro-bevel-it is wasteful to go right to the end (unless there is bad chipping), but the main reason is that the thin metal at the edge over heats much easier.
   True enough, fine wheels are more prone to causing too much heat, but the culprit is usually glazing or loading -that is why the wheel should be regularly dressed, preferably with a diamond tipped dresser.Presumably you are using a white wheel-80grit Alumunium oxide is not too rough but cuts quick and cool becuase it is "soft". You should be able to re-grind with that without having to cool down with water....
   What timber are you using? I have Marples chisels (old with Butyrate compound handles, some with wood handles)-even chopping Wenge does not cause chipping (just rapid blunting).
   Repeated warming and cooling in water is not going to harden the tool steel that chisels are usually made from-I said warming.

   Philip Marcou
1. 
   rod | Jan 17, 2006 02:09am | #5

   Philip, Troy, Mike, Woodmanplus I have a 1750 rpm grinder with a white stone. I work mostly with Ash, Red and White Oak and some Cherry -- these are local woods. When I had the bevel at 25 deg and a 26 microbevel the chipping was worse. Then I was doing more chopping, now it is more paring so that may be a bigger difference. The chisels in question have a pretty clear yellow handle. I will try his way of grinding partially because he is such a good friend. It never occurred to me that I could be hurting the chisels, I knew enough to avoid so much heat that they turned blue. Thanks for your comments.Rod

1. 
   mike4244 | Jan 19, 2006 06:48am | #7

   Rod, sounds like you got the right setup for grinding your chisels. Maybe the quality of the steel is poor. I have an old set of stanley #60 butt chisels, about 40 years old. Also a set of socket handled paring chisels even older. All hold an edge well, if your marples were bought recently possibly you could return them or use them for rough work only. I have three # 60 stanleys I use for rough work besides the full set I have, got them for 25 cents a piece at a garage sale.After an hour or two of flattening the backs and grinding and honing, they are as good as my full set I keep in the shop.

   mike

3. 
   mike4244 | Jan 16, 2006 10:34pm | #3

   Change the grind angle to 25°.Small difference but the edge will hold up longer. Your machinist friend gave you good advice.I use a 60 grit friable wheel. You do not have to grind the entire bevel at one time, grind at 25° each grinding til you have the entire chisel at 25°.

   mike

4. 
   woodsmanplus | Jan 17, 2006 01:20am | #4

   I have a set of those chisels that I bought about ten years ago and I have never had one chip on me and most of the wood I work with is exotic hardwoods.The way I keep them sharp is I use a sharpening guide I bought at woodcraft.I just use different grits of wet ot dry paper that I attach to a piece of glass and when it wears out I just put on another one and I use a good honing oil.When you sharpen them on the grinder is it a slow speed 1750 or highspeed?But like was mentioned earlier,keep them cool while grinding them.Good luck.

   Ken

5. 
   Kleck | Jan 17, 2006 08:28pm | #6

   Marples will not hold a decent edge. I've lost edges on them in less than 3 minutes of use in hard woods. You might Ebay them and get a better quality chisels. I was able to return mine for a refund so didn't need to go the Ebay route. <g>