Know a good video on grinding a nose radius and honing on HSS lathe tools?

[tmenyc]

I think I'm still not getting this right, would love to actually see it happen. Specific as Mikey's descriptions are in the HSS tool grinding encyclopedia at the top of the list, I would benefit from seeing it happen. Part of this is, I fear, that the solutions are very right-handed, and I'm very left-handed. As long as I don't have to write with it, I can switch and do it right-handed, but want to make sure I understand it first.
Many thanks, as always.

Tim

 

[Mitch Alsup]

The sharpening/shaping and honing parts are available via Abomb79 videos.
Don't remember about the nose radius parts.

 

[Bob Korves]

The video creator has created and added more videos since these two.

 

[tmenyc]

Thanks, I'll watch them again!
Tim

 

[Bob Korves]

Ah, yes, Tim, we did this before on Mikey's post! Personally, I find those videos really good and full of great visual information, but then I have seen poor videos and made some poor tools myself. Making exact replicas of existing tool types is not strictly necessary, what is really important is understanding the geometries necessary for a tool to cut correctly and live long enough to do the job. Once you have taught yourself those important skills, for many different metals and types of cuts, then you can make successful tools for nearly any need, and figure out what an unknown tool should probably work best for. The concepts responsible for the tool to cut correctly are the important parts, pretty looking tools are completely optional (though they do have a higher immediate success rate.)

 

[tmenyc]

jeez, I must have forgotten the videos! I have the docs printed and have used them, mostly memorized them. But I forgot the videos. Will page through it again tonight and find them. I'm not looking for exact replicas...but need to see it done right, once.
thanks,
Tim

 

[mikey]

Tim, honing is simple. Just keep in mind that you have two goals - to remove any coarse grinding marks and to create flats that sharply intersect. When you hone the side cutting edge you need to make that face flat so that the intersection between the side and top is sharp. Same for the end and top. The tool cuts at these intersections so creating a very sharp intersection between planes is critical.

Basically, you are trying to make each of the three faces flat, at least at the top and bottom of the face. If you do that for each of the three faces, the intersections will be sharp. Use your coarse stone to remove most of the grinding marks, then the fine to remove the coarse marks, then the extra-fine to create a homogeneous surface. When you are done with each of the three faces there should be no light reflecting off any of the cutting edges.

As for the nose radius, that is simple to do. Create a tiny flat across the front of the tool where the side and end faces intersect, being careful to make the flat even from top to bottom of the tool. Then gently round the sides of that flat so that it blends smoothly into the side and end faces. It is best to keep this flat small, between 1/64" to 1/32" wide, before rounding it. Once you round it, go back and gently hone the top to remove any burrs and the tool is ready to use. Nothing hard or spectacular about this.

 

[tmenyc]

Thanks, Mike, as always. I am getting there. Reground the knife and square, just wanted to see the radius-ing again.
Tim

 

[pontiac428]

I cut large radii on the grinding wheel, but most small radii I do by hand on a 1000 grit diamond hone. Diamond makes short work of tool steel, so a few careful drags across the corner I want rounded is enough, then I follow up with 1600 grit for the final hone. This works for up to 1/16" or so worth of nose. Any more than that can be hand cut with patience, or machine cut with a radius fixture. I prefer using the hones to freehanding on a grinder, since the hones allow me to hold true to the axis. I just did a couple bits yesterday like this.

 

[pontiac428]

Here's a few pics. All done on the 1000 grit hone.