So this morning I decided to do a bit more turning on the ash wood mill.  I needed my round nose scraper to smooth surfaces out a lot better.  How ever learning how to sharpen and grind to an angle for me is some what of a challenge.  I found that my round nose scraper was rather dull and the angle was just so badly off kilter it wasnt even funny.  I had messed it up pretty badly.  So I put the bench grinder tool rest down flat and ground the nose down until it was squared with the round.  Then I got the proper angle for it and started re shaping the bevel.  I then proceeded to finish off the grinding and did a test run on the ash.  Once again it was cutting like a hot knife through butter.  At least thats one successful thing I've been able to master with the HSS tools now I just need to learn how to do the rest of them.  Before you ask NO I DO NOT have angles marked on my tool rest.  I've done it all free handed. 

 

Still need more practice to narrow down I think the sides are a bit rough.  But it works.  (Sorry a couple of the shots are pretty blurred I can always re take them if need be the camera does not like the background I'm assuming.)

 

 

 

 

 

Edited April 18, 20215 yr by AndrewB

Somewhere along the line, I started doing this for my scrapers. I think the idea was totally by accident. I set the grinder table slightly below center and perpendicular to the wheel center (level). Then place the scraper upside down on the table. 

 

The curvature of the grinding wheel creates a grind that is a few degrees off of 90 on the scraper business end. Because the scraper is presented to the grinding wheel with the top edge down, the top cutting edge leads the non cutting edge.

 

I found this method also creates a slight burr on the top edge- due to the grinding wheel cutting direction. That's a little easier than trying to burnish a burr on the top edge.

 

I should have made the wheel, in these drawings, have more segments but I think you can see what I'm talking about-

 

 

 

 

The upside down method is favored by Jimmy Clewes. I grind my scrapers face up at 70 degrees.

 

Now for more Reed Gray (Robo Hippy) says that the grinder created burr is very fragile and comes off very quickly if you use it (which I usually do). He says that a better and longer lasting burr is derived by burnishing. Hone the grinder burr off and then use a burnishing rod to raise a longer lasting burr.

 

You might also try instead of laying the scraper flat on the tool rest hold it at an angle and get a shear scrape.

Yea but if grinding upside down, wouldn't that increase the risk of getting a catch with the tool and the wheel.  With that amount of RPMS it wouldn't be very pretty with a tool catch on a grinding wheel.   The next tool I'm going to have to re grind is my skew its off whack as well.  Either way I just worry about getting a catch on the tools if I were to try it upside down.

No catch the wheel will be turning away from the blade not towards it. I have done this snd it does work but as I said the burr is very fragile. But then the but on all methods is fragile just more so right off the wheel.

I don't think I'm mechanical that much.  I still need to work out how to open up the gaurds so I can change out the blades LOL.  Buffers its simple just take off a couple of nuts and change the wheel done.  I'm going to have to look into this maybe I will try it but for now I will leave things the way they are.

18 hours ago, AndrewB said:

Yea but if grinding upside down, wouldn't that increase the risk of getting a catch with the tool and the wheel.

Maybe I've been lucky but I've never had a tool catch on the grinding wheel. On my low speed grinder, I keep the table within 1/8" of the wheel. With my Tormek, the wheel spins so slow that catches aren't possible, IMHO.

Yea but for me its honestly not worth the risk. If Ive never done something like that I usually play the safe route and don't mess with it.