Tangential tooling

[Gordon]

I have been thinking about making some tangential tool holders for the lathe. I found this which shows one design. There are many other similar designs.

http://theamateurmachineshop.com/index.php/projects/13-tangential-lathe-tooling

Has anyone used this type of tooling and if so there must be some rules on how to grind the tool bits? Any insight welcome before I try making this.

 

[ChazzC]

Starting at 7:18 this video from Eccentric Engineering shows sharpening:

 

[redhunter350]

Gordon, looking at the drawing on the link it appears there is no side clearance/rake on the design ? Forward rake is 16deg but it shows zero side rake.
Here is a photo of one I made a while back -- I copied the design form another chap's photo of one he made. No drawings --yet !! but it has 12deg rake for both front and side. One photo is as machined and the other are hardening

View attachment 088E16A1-B572-423C-88B9-7E9B48EE00A5.jpeg

 

[Gordon]

OK Thanks. That is what was confusing me. I know that it needs both side and rear rake so I was wondering if the rake was generated in how the tool bit is ground. I will keep looking for another design or make my own. The $100 price plus shipping for the eccentric seems kink of steep. Also I have plenty of time to make my own.

 

[ShopShoe]

Sort of a Request.........

I have had it in my head for years that I would like to make one of these, but the other "Round To-its" have been keeping it in the background.

I followed the late Chuck Fellow's experiments back in those days, but did not save his posts, and what he did was not exactly what I was thinking at the time.

Anyway........,

If I make an attempt at this I will post my adventures with it and I would hope ayone else making one of these or a variation of it might post some detailed information that might help us all. I am having a particularly difficult time getting my head around the orientations of the bit necessary to make the sharpening jig that would be required to grind HSS toolbits for this use.

I am using a 7x mini-lathe and have grinders and belt sanders for sharpening and protractors plus angle plates with surface plate for measuring: So, old-school tools and techniques.

Or, If someone knows of a free source for build information (hopefully with plans) I would like to know where to find it.

Thank You for listening,

--ShopShoe

 

[Richard Hed]

OK Thanks. That is what was confusing me. I know that it needs both side and rear rake so I was wondering if the rake was generated in how the tool bit is ground. I will keep looking for another design or make my own. The $100 price plus shipping for the eccentric seems kink of steep. Also I have plenty of time to make my own.

Blondihacks has one that she demonstrates.

 

[awake]

I made one many years ago for my 12.5 x 30 Cincinnati TrayTop lathe, and I use it all the time. Grinding the bit is simple a matter of holding it so that it presents to the grinding wheel as a diamond shape - i.e., rather than the flat sides being horizontal and vertical, the corners are aligned vertically and horizontally. Tip it about 10 degrees and grind the bit, leaving a high spot on one corner of the face, sloping back to the opposite corner. Hone lightly and it is ready to go. Note that I also prepare the bit by slightly rounding the whole corner that will be used for the high spot / leading edge.