Recently decided I needed to know more about sharpening my tools (more would be easy as I learned I didn’t know squat). So I bought Leonard Lee’s Fine Woodworking Book “The Complete Guide to Sharpening”, I read the Fine Woodworking Artilcle written by Jefferson Kolle, and I was horrified at the price of the water cooled Tormex variable speed grinder. Well in NONE of these sources (and several more I have not mentioned, they don’t give a hint at how to use a electrical bench grinder – these things are high speed and can quickly take the temper off of most any thing one wishes to sharpen. Shouldn’t a bench grinder be running much slower to properly sharpen a plane’s knife or a chisel? That is, not to sharpen, but to shape the tools cutting edge preliminary to final sharpening on a stone, sandpaper, whatever??? Am I wrong here that the speed needs to be cut back alot, OR is this a matter of operator responsibility to know enough to use a slow hand and to make sure the heat build up in the tool is carefully controlled by extreme care?
I am perfectly willing to be told to do my sharpening by hand (stone, sandpaper, etc) but I have then so fouled up that they truely do need correcting (getting the cutting edge straight, the nicks out, etc. I have a very small grinder wheel on a WEN water cooled grinder, but Leonard Lee says these things are just too small and put to much of a sharp concavity to the chisel that it weakens the cutting edge so it can’t hold a edge for long.
In short —– HELP for some you guys/gals who know a whole lot more about this than I. (I understand I can put a rheostat on my SEARS bench grinder if it has removeable brushes – havn’t checked the brushes status yet, but can anyone venture an opinion on the accuracy of this statement – the statement about being able to adjust motor speed if the motor has brushes.) Thanks a bunch.
Replies
Actually the average bench grinder is definitely too high speed for "fine" edges and thinner tool steel. It is meant for material removal and reshaping. So to use it for what you need to do just use a fairly light touch, keep a container of water nearby and dip your steel in it often enough to keep it cool.
As for a rheostat (variable speed controller) I doubt that I would bother. They are available for both brush type and brushless motors, but by the time you slow the average grinder motor down that far the loss in horsepower is ridiculous. If I did a lot of grinder work on hard steels I would get a low speed grinder. Since I don't use a benchgrinder for anything that "touchy" very often I just pay a little more attention and keep the water nearby.
Jim
This can get to be a can of worms sans the can or a replacement container.
If you take this post over Knots there are folks that live and breathe scary sharp and the how to's. (see the header for the Knots link)
You can go to http://www.leevalley.com and they have a wide range of of sharpening aides and tools. More than enough stuff in their catalog to give you ideas and direction. All of it will be 1st rate quality and they (LeeValley) are an outstanding company to deal with with a 5 star horde of knowledgeable folks.
I sharpen my own but I'm over and beyound the Tormax system. I use all water cooled grindes up to 6,000 grit. My methods and types of equipment just may be a little rich for you.
Who ever invented work didn't know how to fish....
Hi - Lie Nielsen has just launched a video in the US with David Charlseworth (a UK maker and teacher) about sharpening which, in a few very easy steps, will help you get plane blades sharper than they've ever been. I should know - I am studying with David at the moment and he really knows what he's on about - I think Fine Woodworking are due to give the video very favourable reviews so it maybe worth checking it out - I expect L-N will have the vid on their site.
Best of all - David's methods do not involve expensive kit like the Tormek - just 3 water stones, a plane blade, and ruler and some elbow grease!
I would buy an 8" ,1725 rpm grinder. Cost more but worth the extra cost.If you go with a 6" 3450 rpm grinder ( lower cost and readily available) you can do much better work by the following method. When grinding a plane iron, chisel or turning tools, start grinder, let come to full speed and shut it off. Commence grinding until the wheel stops. Less heat , more control, better job in the long run.
The wheels that come with a new grinder are good for lawnmower blades and such, buy a friable wheel for wood working tools. Some are white, others Iv'e used are pink. These wheels wear faster, hence less heat build up.Also I would buy a diamond point dresser to shape and clean the wheel. These dressers are very easy to use, just move them along the rest as you push in LIGHTLY.
I also have a Sears grinder, it has an induction motor. I do not know enough to help you on the rheostat thing. Try calling a electric motor repair place, they would know.
mike
Mike: Thanks for your response. Some great tips. In the meantime I sprang for a Delta machine that has two wheels, one of which is water cooled and does have two white wheels. As I progress in my skills I will have to try the pink and blue wheels. Thanks again for your ideas.
You picked a great tool, I have had mine for many years. I can sharpen my planer and jointer blades on the wet wheel with jigs. I have never used the small wheel but I recently bought from Woodcraft a 8" grinder with white wheels for 80.00 You will want one of these also as the wet grinder is slow when you have a lot of metal to remove.
JB, you won't need another wheel, the white wheel is a friable wheel. Congratulations on your new grinder.
mike
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