How To Grind A Hss Turning Tool

[Dan_S]

Timing is every thing. I need to learn to grind my own HSS bits. I need to find out how to grind a bit for cutting the recess in a medallion. SO how do you guys grind the tip to allow clearance when cutting the recess? Is the tip still centered on the diameter ?

are you talking about cutting a grove into the face of a part?

 

[mikey]

Hey Ron,
I'm not clear on how the tool will be applied to a medallion or what recess you're referring to. Can you post a pic of the project set up in the lathe? Then we might have more useful input for you.

Thanks

 

[Dan_S]

Hey Ron,
I'm not clear on how the tool will be applied to a medallion or what recess you're referring to. Can you post a pic of the project set up in the lathe? Then we might have more useful input for you.

Thanks

I think he is talking about a trepanning tool, but I'm not 100%.

 

[mikey]

Oh, okay. Thanks, Dan. By the way, my friend who was looking at CBN wheels said to tell you that you do really nice work. I agree!

Let's see if he posts a pic.

 

[Dan_S]

Oh, okay. Thanks, Dan. By the way, my friend who was looking at CBN wheels said to tell you that you do really nice work. I agree!

Let's see if he posts a pic.

Thanks man.


O and I knew this what out there some place. Keith Fenner making a trepanning tool.

 

[RonWB1957]

The second from the left shows what I need to do. IT allows to either be etched or an insert glued in. Thanks

 

[mikey]

Typically, trepanning leaves a remnant in the center - not the case here. It would be easier to cut it with a knife tool by spotting the center with a spotting drill to the depth of the hole, then turning from the center to the rim. In brass, this would be a shallow roughing cut and a skim finishing cut. The tip of the tool would be on center and the side cutting edge would parallel the ways to produce a square shoulder.

A knife tool looks like this:

 

[RonWB1957]

Thank you. I now see what I was doing wrong. Not enough side clearance. The lower portion of the bit was hitting the side wall, leaving a chamfer.

 

[mikey]

Thank you. I now see what I was doing wrong. Not enough side clearance. The lower portion of the bit was hitting the side wall, leaving a chamfer.

Yup, hope it turns out okay. If not, come on back.

 

[Dan_S]

Ron, what kind of saw are you making?