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View Full Version : Sharpening with a grinder - direction and felt wheel



Dan Karachio
07-12-2010, 6:35 PM
I suppose someone will tell me I am wasting my time, but I bought a 1750 6" grinder and thought I would use it along with my wet stones for chisels and maybe plane blades (only those that are in real rough shape). It is this model: http://grizzly.com/outlet/6-Bench-Grinder-with-Wide-Wheel/T21990

A few questions. The grinder works by spinning down and toward me. What is the proper direction? I think I can rewire it to go in the opposite direction, but should I? This gentleman says that for the felt wheel, it is highly recommended, but he is working freehand without a tool rest: http://www.wkfinetools.com/contrib/jThompson/howTo/sharpFeltWheel/feltWh2.asp

I think down and toward me is okay. Note, I do have a Veritas jig that can be used on either the felt wheel or the wider grinding wheel (modified it).

My main question is, how do you all prepare a new felt wheel. Mineral oil then the green stuff? A little detail would be greatly appreciated.

P.S. I have now reached the point where I have spent enough on wet stones, guides of various types, a Worksharp, granite slab, and this cheapo little bench grinder to where I have easily surpassed the price of a Tormek!!! Arrrrggggg!!!! :D

Stephen Cherry
07-12-2010, 10:37 PM
Stone with it heading into the blade, felt away.

Rick Markham
07-12-2010, 11:14 PM
Dan I just cut to the chase and bought a Tormek T7 today... :D Good thing is though you needed the whetstones anyway, so you can subtract those from your total, and your probably still ahead ;) I now have way too much money into sharpening tools, but fortunately I did my research and they all get used regularly and give me some razor sharp tools.

On the Tormek, (for plane blades) the wheel rotates towards the business end of the blade. (top of the whetstone traveling away from you)

Tim Put
07-13-2010, 12:23 AM
Felt wheels MUST turn away from the edge. It's fantastically dangerous to do otherwise. The edge can dig in, if that happens the tool can be thrown at up to (6"*pi*3450rpm) 60ish mph. :eek:

You can either reverse the grinder, or point the tool towards the floor and hone with the underside of the felt wheel.

Grinding wheels work better (less likely to burn the edge) when they turn towards the tool.

Rick Markham
07-13-2010, 1:22 AM
Felt wheels MUST turn away from the edge. It's fantastically dangerous to do otherwise. The edge can dig in, if that happens the tool can be thrown at up to (6"*pi*3450rpm) 60ish mph. :eek:

You can either reverse the grinder, or point the tool towards the floor and hone with the underside of the felt wheel.

Grinding wheels work better (less likely to burn the edge) when they turn towards the tool.

Yeah... that won't buff out! :eek:

Dan Karachio
07-13-2010, 7:30 AM
Thanks Tim! I mean it, thanks a lot!
I can manage having the tool supported at the bottom of the wheel to avoid this.

Can I ask you about preparing the wheel? Mineral oil and then the green stuff right? How much mineral oil is what I am not sure of. How do you apply it?

Rick, you are a smarter tool buyer than me! :)

David Weaver
07-13-2010, 7:34 AM
I'd just do green stuff on felt. Mineral oil on leather. The felt should hold the abrasive by itself - you don't really need much of it.

Start with light pressure - even though the green stuff is tiny abrasive particles, it can remove a lot of metal fast and dub an edge on a felt wheel.

John A. Callaway
07-13-2010, 8:46 AM
I saw somewhere ( book, magazine.... ) where the author mounted the grinder to a plywood plate and a lazy susan swivel base, with a locking pin to keep the grinder in place, and the wheel covers were swapped around on the felt wheel side, so you grind towards you on the stone, spin the whole grinder around on its base, then use the felt wheel with the grinder spinning away from you. seemed pretty simple to set up the whole rig.

george wilson
07-13-2010, 9:57 AM
I NEVER buff with a fast rotating strop. They kept a Tormek in the Richmond Wood Craft store. Every time I went in there and tried my sharp knife on that infernal thing,I made it duller.

I know that some people that I respect like to power buff,but not I,and I have done more buffing(in the normal sense) than 99.9999999999% of other craftsmen.

Steve Dallas
07-13-2010, 3:17 PM
I suppose someone will tell me I am wasting my time, but I bought a 1750 6" grinder and thought I would use it along with my wet stones for chisels and maybe plane blades (only those that are in real rough shape). It is this model: http://grizzly.com/outlet/6-Bench-Grinder-with-Wide-Wheel/T21990

A few questions. The grinder works by spinning down and toward me. What is the proper direction? I think I can rewire it to go in the opposite direction, but should I? This gentleman says that for the felt wheel, it is highly recommended, but he is working freehand without a tool rest: http://www.wkfinetools.com/contrib/jThompson/howTo/sharpFeltWheel/feltWh2.asp

I think down and toward me is okay. Note, I do have a Veritas jig that can be used on either the felt wheel or the wider grinding wheel (modified it).

My main question is, how do you all prepare a new felt wheel. Mineral oil then the green stuff? A little detail would be greatly appreciated.

P.S. I have now reached the point where I have spent enough on wet stones, guides of various types, a Worksharp, granite slab, and this cheapo little bench grinder to where I have easily surpassed the price of a Tormek!!! Arrrrggggg!!!! :D

You are going to get hurt. You heard it here first.

Tony Shea
07-13-2010, 3:38 PM
You are going to get hurt. You heard it here first.


I'm not sure what you mean by this comment. Seems as though the OP received some sound advice that he aknowledged about which way the buffing wheel should rotate. Tim was right on the money as far as how dangerous it could be to buff with the wheel spinning in the wrong direction. Not sure why he is going to get hurt, other than his wallet which is the case with me as well. Sharpening turns into an obsession.

I use a grinder for the initial sharpening and the wheel is supposed to spin toward you and down as yours does. Employed with a rest this position is absolutely safe and is the proper way to do this. Just keep a cup of water close by and dunk your tool more often than you think is neccessary. Once your edge goes blue you've lost the temper in that portion of the blade, which you may already know. It sucks to have happen though as these tool steels are really a pain to grind a significant amount off. I use the Veritas rest with the 3M white 80grit wheel. I find the jig that holds the blade to be akward and just use my fingers and eye for a square edge while checking with a square often. Once you get a proper hollow grind it is all gravy from there. Probably more info than you needed, sorry bout that.

Steve Dallas
07-13-2010, 3:53 PM
I'm not sure what you mean by this comment. Seems as though the OP received some sound advice that he aknowledged about which way the buffing wheel should rotate. Tim was right on the money as far as how dangerous it could be to buff with the wheel spinning in the wrong direction. Not sure why he is going to get hurt, other than his wallet which is the case with me as well. Sharpening turns into an obsession.

I use a grinder for the initial sharpening and the wheel is supposed to spin toward you and down as yours does. Employed with a rest this position is absolutely safe and is the proper way to do this. Just keep a cup of water close by and dunk your tool more often than you think is neccessary. Once your edge goes blue you've lost the temper in that portion of the blade, which you may already know. It sucks to have happen though as these tool steels are really a pain to grind a significant amount off. I use the Veritas rest with the 3M white 80grit wheel. I find the jig that holds the blade to be akward and just use my fingers and eye for a square edge while checking with a square often. Once you get a proper hollow grind it is all gravy from there. Probably more info than you needed, sorry bout that.

He needs to stand next to somebody and watch this being done properly and not read an explanation about it on a woodworking forum.

Tim Put
07-13-2010, 4:11 PM
As for prepping the wheel: I'd recommend truing the wheel before applying compound, I only decided I needed to true mine after, which made it a bit messy. I used a small sanding drum in a dremel tool, both drum and felt wheel spinning. After that, nothing but compound.

With all due respect to those who differ, buffing wheels do work for sharpening. The technique required is different than for general purpose buffing and takes some practice. When you buff, put the heel of the bevel on first and then with light pressure slowly raise towards the tip until the sound just starts to change to a wispy buzz, sorta like paper tearing. That's when you're just barely touching the edge and will get the best results.

P.S. Wear eye protection when buffing or grinding.

Edit: I know it's a cliche, but I really do mean "with all due respect", respect however does not mean absolute deference in all matters.

Tim Put
07-13-2010, 4:17 PM
He needs to stand next to somebody and watch this being done properly and not read an explanation about it on a woodworking forum.

That would certainly be nice, but it's not necessary, nor is it possible for many.

I've never been taught any woodworking skill face-to-face, everything has been books, trial-and-error, and the internet. There are a lot of others like me, many of whom turn out quite respectable work.

I've never been hurt by my grinder setup, but I did receive a nasty cut to my middle and ring fingers last week when my right hand just barely brushed the freshly honed gouge my left hand was holding. Nice and sharp, didn't hurt at all, just bled. :o I knew I should've set the gouge down before loosening the carving vise. :o

Steve Dallas
07-13-2010, 9:51 PM
That would certainly be nice, but it's not necessary, nor is it possible for many.

I've never been taught any woodworking skill face-to-face, everything has been books, trial-and-error, and the internet. There are a lot of others like me, many of whom turn out quite respectable work.

I've never been hurt by my grinder setup, but I did receive a nasty cut to my middle and ring fingers last week when my right hand just barely brushed the freshly honed gouge my left hand was holding. Nice and sharp, didn't hurt at all, just bled. :o I knew I should've set the gouge down before loosening the carving vise. :o

I think you forgot the "but I did stay at a Holiday Inn Express last night" part of your post.

Tim Put
07-13-2010, 10:02 PM
It might be an American/Canadian cultural divide, but I honestly don't know what you mean by that. Fortunately I'm not particularly bothered to know.

I get pretty good results trying to emulate a few generous (often, but not always, professional) craftsmen I look up to (who get fantastic results with the methods I am emulating). In kind, I'll try to pass on what's worked for me so far.

Dan Karachio
07-13-2010, 11:00 PM
Thanks everyone. Actually Steve, I have been thinking along the same lines. The grinder was on sale and I could use it for other things so I bought it. However, I am not in a hurry to do something I really am not sure about with sharp tools and fast spinning objects. I may just stick to my stones and leather strop for now and then some day, when I feel I deserve it, get a Tormek and use it. If I do try the felt wheel it will be in the right direction - spinning up and away.

However, Tim's and Tony's advice is just as much appreciated and I don't think Tim deserved what could easily be interpreted as sarcasm. Chalk it up to the internet where you can't read faces, expressions and tone.

Funny, but as for standing next to people, I have done quite a bit of that and seen those who make a living with wood working and carpentry do things that I learned NOT to do right here on the web and a couple times they ended up screwing up a nice piece of wood, a tool or their own hands.

John McClanahan
07-13-2010, 11:09 PM
Don't try to rewire the motor to run backwards. If you do, the nuts that hold the wheels on will not stay tight. Thats why the left side wheel has left hand threads.

John

Steve Dallas
07-14-2010, 6:30 AM
Thanks everyone. Actually Steve, I have been thinking along the same lines. The grinder was on sale and I could use it for other things so I bought it. However, I am not in a hurry to do something I really am not sure about with sharp tools and fast spinning objects. I may just stick to my stones and leather strop for now and then some day, when I feel I deserve it, get a Tormek and use it. If I do try the felt wheel it will be in the right direction - spinning up and away.

However, Tim's and Tony's advice is just as much appreciated and I don't think Tim deserved what could easily be interpreted as sarcasm. Chalk it up to the internet where you can't read faces, expressions and tone.

Funny, but as for standing next to people, I have done quite a bit of that and seen those who make a living with wood working and carpentry do things that I learned NOT to do right here on the web and a couple times they ended up screwing up a nice piece of wood, a tool or their own hands.

Your edges will be just fine coming off the grinder and then honed on your bench stones. Buffing is not all that it's cracked up to be, unless you're polishing sterling flatware, a tea service, or something like that.

Steve Dallas
07-14-2010, 6:31 AM
It might be an American/Canadian cultural divide, but I honestly don't know what you mean by that. Fortunately I'm not particularly bothered to know.

I get pretty good results trying to emulate a few generous (often, but not always, professional) craftsmen I look up to (who get fantastic results with the methods I am emulating). In kind, I'll try to pass on what's worked for me so far.

Just a joke from a silly commercial that runs here in the States. No big deal.

Tony Shea
07-14-2010, 9:14 AM
I really didn't see the sarcasm myself as I've seen the commercial many a times, unfortunatly. It is def hard to read what is meant especially with the vast variety of locations we come from here. I got the joke and think it was in good humor.

I also agree that buffing your edge on a felt wheel is not all it's made out to be and could possibly do more harm than good. It's really not the right tool to use for final honing of cutting tools as it is spinning much to fast. A leather strop should be plenty sufficient. The buffing wheel is def nice to have on the grinder for many other applications though. I use mine just as much as the grinding wheel, just not for cutting tools.