Author Topic: Drill Sharpener  (Read 67 times)

f350ca

Drill Sharpener
« on: April 02, 2019, 07:44:45 PM »
Built a tool grinder a LONG time ago to grind what would be an acme cutter for the lathe but used them on the shaper to cut racks for the cnc plasma cutter. The intent was to use the platform for other attachments that never got made. Well we finally started.
Based the design on a couple of other sharpeners I found on the net.
This jig orientates and positions the bit to get the flutes level. The stop is set , then the bit can be turned to get the other edge at the same clearance angle and length. The angle plate at the end swivels to line up to the bit and the scribed lines aid in getting it flat.

f350ca

Re: Drill Sharpener
« Reply #1 on: April 02, 2019, 07:48:31 PM »
Once set on the carrier the bit is held in this attachment that swings the bit over the face of the wheel. The cutting angle and clearance angle can be set to whatever you want. A screw at the bottom of the holder sets the depth of cut, spark out on both edges and the web is centered.

woodchucker

Re: Drill Sharpener
« Reply #2 on: April 02, 2019, 08:48:56 PM »
nice, but I'm missing something.
First, that right angle plate with the etched lines... did you make that, or is that a tool that can be bought?
When you set the bit on the stand, how do you know you are transferring the same angle to the grinder?
How do you set relief.. that looked like a shallow grind, not one that needed to remove much relief. if you were reshaping a bad tip, would you just do the relief by hand or will this handle it?
Jeff
Clausing 8520   SB Model 9a - power hacksaw, Milwaukee band saw in a table.  Delta Rockwell Surface Grinder (not online yet .. being rebuilt where am I going to stick this)
For pics: https://imgur.com/user/woodchucker/posts

f350ca

Re: Drill Sharpener
« Reply #3 on: April 02, 2019, 09:02:47 PM »
The plate was just a piece of aluminum angle, I fly cut the surface then scribed the lines using a single lip cutter as a shaper bit. Was tedious scribe a line, come back step over .05 then repeat.
There's a finger welded to the end of the angle that the other web is pressed against, you can just make it out in the one photo. You hold the bit against it and bit rotates as you slide it back and forth. Once the lip facing up is aligned to the grid you set the back stop. Now you can flip the bit, with it against the finger and the back stop its aligned again.
The head on the grinder will swing to set the cutting angle, here its at 118 deg, theres another swivel below it to tilt the whole thing to give the clearance angle at the lip. The material at the back is ground away on the bench grinder. Guess I could increase the clearance angle and do it on the machine but its faster by hand and not critical.
This one was in rough shape, needed a lot ground on the edges and lots on the back.

Greg

woodchucker

Re: Drill Sharpener
« Reply #4 on: April 02, 2019, 09:17:20 PM »
got it, that filled in a bunch of things I missed in the pics. nice job on the build.
I was curious about the face truing tool, and saw you made that as well. It looked like it was made for it.


Overall a nice job..
Jeff
Clausing 8520   SB Model 9a - power hacksaw, Milwaukee band saw in a table.  Delta Rockwell Surface Grinder (not online yet .. being rebuilt where am I going to stick this)
For pics: https://imgur.com/user/woodchucker/posts

f350ca

Re: Drill Sharpener
« Reply #5 on: April 02, 2019, 09:43:19 PM »
This is the mechanism that sets all the angles Jeff. Stole some of the ideas from a Gorton grinder.
The bodies are cast iron, the degree marks are at 5 degrees, the extra lines on the center section act as a verier to give 1 degree readings on the swing and tilt. Split cotters lock the movement.