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Derek Cohen
08-01-2009, 2:23 PM
Can one get excited about a grinder? Well, not really ... I'd say that you need to get a life. However ...

I like to keep things simple, although my set up looks anything but that :) It has, in fact, just got simpler ... and better ... and easier ... and I am excited that sharpening will take less effort than ever (yes, I do have to get a life).

I have been using a Tormek for hollow grinding for almost two years. It is really excellent for grinding safely to the very edge of the bevel. I also have an 8" half speed dry grinder. This is used for plane and chisel blades as well, especially for those requiring the removal of a fair amount of steel or where the steel is harder than ideal for the Tormek (e.g. HSS, D2).

My plan has been to develop the dry grinder for my lathe chisels. I had been looking into buying the solid Wolverine Grinding Tool Rest to replace the LV tool rest. I liked the idea that it interchanged a tool rest for bench chisels and plane blades with a rest for lathe chisels. I have been freehanding all my lathe chisels to date, but I realise that, while this is fine for spindle work, I will need to improve the accuracy of complex grinds as I begin to do more bowls.

The Wolverine is not available in Australia, and so I had begun to look at alternatives. The one that caught my eye was a recent product from Tormek. No, not another wet grinder ... but a tool rest for a dry grinder, the Bench Grinder Mounting Set BGM-100 (http://www.tormek.com/en/accessories/bgm100/index.php) .

This is not really a new product, but a packaging of the universal support and adjustable mount. It comes with a manual for setting up and use.

So this is this one I bought, and have just set up, and used. There it is ...

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Basic2.jpg

The grinder is set up with a blue Norton 46 grit 3X wheel and a white Norton 46 grit wheel.

Note that I actually have just the single universal support (the tool rest) for the grinder. The second one here is borrowed from the Tormek. I do have two mounts so that a support can be swapped from one side to the other.

There are also two types of tool jigs: the chisel/plane blade holder and a flat rest. I do not, as yet, have any for lathe chisels.

The chisel/plane blade holder is terrific for grinding a perfect hollow, while the flat rest allows for freehanding a hollow or grinding a skew (or any other custom need).

What is great is that one can move between the machines (Tormek and grinder). This is facilitated by the ability to set the grinding angle exactly when using the AngleMaster:

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Settingbevelangle.jpg

Here is a chisel I re-ground from scratch. It took about 1 minute or less to set up the angle to 25 degrees and a couple of minutes to grind fully..

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Grindingchisel.jpg

A few swipes on my waterstones ..

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Honedchisel.jpg

I also ground the camber for a D2 jack plane blade. To do this I used the flat rest ..

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Grindingjackcamber.jpg

After honing ..

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Microbevelandcamberedblade.jpg

What I like about this set up is that it is so easy to obtain a repeatable angle, as easy as to grind a clean camber, and the promise of great flexibility and range in grinding all types of blades.


Regards from Perth

Derek

Richard Dooling
08-01-2009, 3:20 PM
Can one get excited about a grinder? Well, not really ... I'd say that you need to get a life. However ...


Funny you should bring this up. I just replaced my LV grinder rest with the Wolverine. It is simple, accurate, stable and incredibly fast with easily repeatable results. I just came in from my shop where I reground the primary bevel and honed a 1” bench chisel in about 4 to 5 minutes. The only jig was the Wolverine sliding arm with the pocket on the end. Grind, remove the chisel to check progress, put it back to the exact same position and grind some more – hone and done. I can’t believe how this simplifies the job!

BTW thanks for all your very educational posts and your web site. You and some others here have really helped me start thinking about woodworking and woodworking tools in new ways.


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Auguste Gusteau
08-03-2009, 11:18 AM
Well done, Derek, a good idea and a good realization.



Auguste who apologizes for his bad English

Danny Burns
08-04-2009, 8:44 AM
Thanks for the post!

I have a Tormek, and will be modifying my grinder to match it.

I also like your hollow grind/honing angle approach, as it keeps one working rather than sharpening all the time.

Richard Dooling
08-05-2009, 8:58 PM
Derek, could you please tell me what grit wheels and what grade you are using on the dry grinder? That looks, to this untrained eye, to be a Norton 3X blue wheel of a fairly coarse grit. I'm thinking that even the 46 grit wheel should not pose problem going directly to the bench stones since the bearing surface on the hollow grind is so small. I've already moved off a 120 grit wheel to a 60 and see no problem with going right from the grinder to the bench stones.

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Derek Cohen
08-06-2009, 2:26 AM
Hi Richard

I use a blue Norton 3X 46 grit, and on the right is a white 46 grit that came with this half-speed 8" machine. The white wheel has not had any wear as I only had a single rest (LV) until now and this went on the 3X side.

The coarser the better when it comes to keeping the steel cool when grinding. The 3X wheels grind the coolest as well. I'd say that the white wheels are next best. The grey wheels are the worst, but fine for HSS where heat is not an issue.

I would not go above 60 grit, and probably would avoid even that if you are in the least heavy-handed. 120 grit is fine for HSS lathe chisels, which is why many grinders come with one.

For interest, here is my sharpening centre (still has doors to go on the sink cabinet ..

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Sharpeningcentre.jpg

... and Shapton waterstones used (1000/5000/12000) ...

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Grinding%20Nirvana/T-Waterstones.jpg

Regards from Perth

Derek

Richard Dooling
08-07-2009, 5:54 PM
Thanks Derek,

You and some other folks in a thread I started on wheel grits have been very helpful. I just ordered the Norton 3X grade I 46 grit from TFWW. BTw twice I've ordered from TFWW and twice Joel has taken the order himself - a good gut to do business with.

I will keep the white 120 grit wheel for now at least. Like you I had a decent rest on just one side of my grinder unti recently - it's nice to feel that both sides are fully accessable now.

Ohhhhh - you have running water in your shop!


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