Here's a quick look at how I machined several pieces of aluminum to make the tangential tool holders. A version if it was written up in "The Home Shop Machinist" Jan/Feb 2009 issue. I figure there had to be a better way to mill the tool block than what the writer had shown. He made his on a Sherline. I made mine on a Grizzly Mini-Mill or X2 style milling machine. I also have a Sherline lathe/mill combo.
I'm not going into a lengthy description or give dimensions. It was a tool holder I always wanted to try, plus I wanted to see if I could use less steps to accomplish the same thing. Weather I did or not is still in the air. The proof being in the fact that I have to turn the holder clockwise or counter clockwise from square to the cross slide table. You are supposed to be able to both face and turn without having to move the holder. Not true in my case. It does cut well though.
First pic is of the vise setup. Turned 12 degrees clockwise from square.
The two blocks of aluminum. 1.5" square by about 2" long.
The first of many cuts.
One side completed.
Both parts have the first side cut at 12 degree angle.
With the vise still at 12 degree the parts are clamped on there side that was cut earlier.
The second side finish milled.
Next will be the hole for the clamp and the slot for the tool bit. The one that's completed was my prototype and has a 1/4" slot for that size tool bit. The other two will be for a 3/16" and 1/8" HSS tool bit.
A rough guestimate of where the tool clamp will be.
Disregard the dimension on the scale. Locating the hole, just approximate.
Hard tapping the hole 1/4"-20. I just tighten the drill chuck enough so that the tap won't break when it hits bottom. How do I do it? Its just a sense of touch and some guts. <grin>
Milling the 3/16" tool slot.
Checking fit of the tool bit. That's about as deep as you'd want to go.
Both slots cut. Notice that when the holder is laid down in it's cutting position that the tool will be slanted 12 degree away from the center line.
All three lined up. 1/4" left, 1/8" middle, and 3/16" right.
The tool needs to be about .560" high or thick. So I'm using the prototype to scribe a line on the other two.
A quick trip through the band saw. I use a 6 tooth per inch raker tooth. Cut's like butter. Then a quick trip through the mill to clean up the saw cut.
And here is the tool on try out cutting. The blade holder is nothing more than a piece of steel with a hole in it and one surface mill so when clamped it will be parallel with the tool.
That's it for now. I'm not going to go and develop this much beyond some clearances so I can face larger diameter pieces. I want to concentrate on building the coke bottle engine I've started. This was an experiment to see if I could do the job in less set ups than the author used in his article. I think I succeeded. I'm just not sure I have some of the angles right. I did this to see if I could make a tool to better turn the bronze material of the coke bottle engine. I think it would but will resort back to the regular tool post that came with the Sherline for now. Perhaps when I finish the engine I'll resume on the tangential tool holder.
Questions?
Regards,
Bernd
