# 16° Tangential Tool Holder



## LJP (Aug 28, 2013)

After looking at many different versions of the tangential tool holder (both here and elswhere) this is what I made. 
The holder is 1" square CRS, the tool is 5/16", ground to a 30° point, roughed on the belt sander and finished on the disc sander, honed quickly on an arkansas stone. I did round the front edge slightly, but only on the arkansas stone, so it is very little. The tool is held at 16° angle to the front, but the tool is straight in line with the axis of the holder, I did not angle it to the right, as most that I have seen are. 
The 1/4 -20 allen cap screw is counterbored flush on the left side, it pulls a "round nut" with a chamfer on it against the tool. The hole for the tool was drilled on the mill at a 16° angle and then filed square by hand. It took 45 minutes to file it to a snug fit. The hand filing was not a big deal to do at all. 
I rabbetted the holder to fit into the QCTP. I tried it out on some 3/4" drill rod, it is good hard stuff. The cutter gave a good finish, the best was as a shear cut. I think as I use this tool, it needs a little more round on the point, and will do an even better job. 
The deepest cut I took so far was .040", the tool was very rigid . It was an effortless cut on the SB13. 
Here are some pictures.
Larry


----------



## Dave Smith (Aug 28, 2013)

looks good and solid--good job---Dave


----------



## melsdad (Nov 14, 2013)

I like the looks of this tool holder! I may have to make one for myself


----------



## pineyfolks (Nov 14, 2013)

Simple and sturdy clamp, I like it.


----------



## LJP (Nov 14, 2013)

Thanks Brian and Bill,
Yes, it works very well. That bit doesn't slip at all, even with a heavy cut.
Larry


----------



## Philco (Nov 14, 2013)

LJP, I missed this when it was posted on 8-28-13. This is a solid looking design with the split cotter clamp. I've been wanting to make one for some time, there just always seems to be something more important ahead of it. Thanks for the time you spent making it and sharing it with others.This has given me some more ideas when I do get around to making one.
Phil


----------



## LJP (Nov 14, 2013)

Phil, you are quite welcome. Thanks for letting me know the term "split cotter clamp", I have never heard it before.
Larry


----------



## eightball (Nov 14, 2013)

Nice job.  Im not a fan of filing but looks great!


----------



## itsme_Bernie (Nov 14, 2013)

LJP-

People definitely underrate filing as a machining process.  By the time you set up and complete some operations on a mill, many things could be done with a good file and a little elbow grease... And with a nicer finish!

I really like your take on this.  Simple and clean looking, and solid.  I really like the counter bored and chamfered "nut" section.

I was wondering- did you run a nice file over that top surface?  It looks ground, but has that nice curve down to where the tool cutting edge exits, so I think it couldn't be ground?  


Bernie


----------



## LJP (Nov 14, 2013)

Thanks guy's, the filing is really no big deal. I guess that's a holdover from my woodworking experience. But then I guess I file more than most of my woodworking colleagues as well. I tend to buy a lot of files, and use them a lot without thinking about it. They do the job, and quickly if your good at it.

Bernie, no. All the outside surfaces were run freehand on the edge sander, probably a 180 grit belt.

Larry


----------



## Dranreb (Nov 14, 2013)

Nice work Larry, what I like about your design, is that the 16deg angle means the holder clears a large diam workpiece nicely, it also does right and left hand, which is handy...

I've been thinking on how to cure those deficiencies in mine, looking at your design has given me a prod! 

I like your clever split cotter clamp, but I'm wondering if it may be too efficient, I like the fail safe function of mine and it worked well when I tested it,  have you tried over loading it to see if the tool drops safe under extreme load?

Bernard


----------



## LJP (Nov 14, 2013)

Bernard, my design is pretty solid, no it will not drop under a heavy load. But then, that is what I was trying to achieve. My understanding of most any kind of machining is to go for rigidity. When would you ever want a tool to slip? My feeling is, you should not overload the machine.
Larry


----------



## Dranreb (Nov 14, 2013)

I agree rigidity is what we're all aiming for in tool design. 

But  me being a newbie amateur, I'm still trying to think like a machinist,  and I have had the occasional slip up, broken a couple of newly ground tools practicing  on different materials,  trying various Speeds, DOC, feed rates etc..

I have an Atlas, not the  strongest machine out there, so I like the fact idea that a 'slip  clutch' can be built into a tangential tool holder without sacrificing  rigidity, others had mentioned this feature in other posts and it just  seems a good idea to me...

Just my way of thinking.

Bernard


----------



## LJP (Nov 15, 2013)

I guess I go the other way, I use conservative feed rates, and don't try to push machines to their limits. I seem to get better results that way. 
Larry


----------



## Getaway (Nov 15, 2013)

What a fantastic job!  I have been wanting one of those for my 12x36 Atlas.  Now I have another project.

This form is such a great place to learn.  Many thanks to all of you who share.


----------

