What is the best tutorial on how to sharpen drills using the U2 grinder?

[Janderso]

I just bought the Shars version of the ubiquitous U2 tool and cutter grinder.
It came with the full accessory kit including the drill bit tool.
I have figured out the clearance angle but how, what are the settings to grind the cutting edges?
There are a few very poor quality videos in some other language that has not done much for me.
Thanks,
Jeff

 

[Ulma Doctor]

you'll decide the angle for the cutting edge.
it will usually be 59° or 67.5° unless you are sharpening/making a spotting or right angle drill
59° for 118° bit
67.5° for a 135° bit

 

[ACHiPo]

Jeff,
Did you see this article that Rex posted a while back?
https://www.icscuttingtools.com/pdfs/Drill_Point_Geometry.pdf

The 3-D descriptions and photos make me scratch my head, but I suspect there's a goldmine in there for optimizing drill cutting angles.

 

[Janderso]

I haven’t seen it but I will.
The geometry is getting better but the split point is off.
I’ll get there.
Thanks for the link Evan.

 

[Janderso]

Still working my way through the article.
The drill attachment allows you to set depth, pivot and hold the drill bit securely

The attachment holds the drill bit at a 45 degree angle.

There are so many ways of adjusting the 4 pivot points, it truly is an amazing tool.
My goal is to identify the setting for each adjustment of the head.
I'm surprised nobody hasn't come up with a way to grind the perfect 118 degree drill bit using this Universal grinder. If the settings are published I haven't found it.

 

[Stonebriar]

There is not a lot of info on using these things. The few videos I found are not that helpful.

 

[NC Rick]

There are so many ways to setup these machines wrong, it takes a bit more dedication than I have given it. Almost totally impractical for a single drill or anything. Don't get me wrong, these a cool little machines but I find them time consuming. I hope to have a lot more time which needs consuming!

 

[Janderso]

There are so many ways to setup these machines wrong, it takes a bit more dedication than I have given it. Almost totally impractical for a single drill or anything. Don't get me wrong, these a cool little machines but I find them time consuming. I hope to have a lot more time which needs consuming!

The ability to step up to the grinder, set it to pre-marked or known positions for grinding your standard drill bit is the intended idea.
I'm sure there are plenty of uses like touching up carbide at exact angles or grinding lathe tools.
I'll get to know this little fellow over the next few months and report back.

 

[NC Rick]

I hope you share your experience as I have yet to do a drill bit. I have done single lip mill cutters and lathe tools as well as various brazed carbide tooling.

 

[pontiac428]

Jeff, your problem from the photos above is clocking. I had to spend some time grinding until I figured out the tricks. Then I scribed reference lines on my drill work head for reference.

The absolute best reference for this particular grinder is Harold Hall. He illustrates all of the failure modes like clocking error and excess stickout with diagrams of cause and effect. At the end of the day, it is incumbent on the operator to understand the tool, so a 1-2-3 step guide isn't enough to make one proficient. You really gotta wrap your head around it to become a natural.

I did watch a YT video with a couple of old Chinese guys grinding bits in bad lighting. It was enough to click the process into place for me, followed by a sit-down with Harold Hall. If you do that, you will know exactly what you are doing wrong and how to fix it. Bear in mind that heavily worn bits need to be re-clocked after roughing because of the helical flutes.