• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
  • PLEASE: Read the FORUM RULES BEFORE registering!

Precision Drill Sharpener

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#1
Quite a while back I built my version of John Moran's ( aka: gadgetbuilder ) drill sharpener. While the machine I built works great , I got to thinking, since I built it , I have more and better equipment, much better and more tooling. I want to build another one with a more powerful motor to make sharpening larger drills easier and I want to hold tighter tolerances. The construction of my first machine was mostly aluminum, but I want to make the new one all steel. I was also considering making it an attachment for my newest T&C grinder but that is still up in the air. ( if I make it a stand alone machine I can use it on the bench sitting on my stool or in my wheel chair.)
So....... I started today.
image.jpeg I started with the trunion supports since they are most difficult. These pieces have to be exactly the same height for each pair.
image.jpeg The bearing holes have to be reamed as exact as possible to be in line. Any misalignment and they will bind. I milled them from cold finish steel.

image.jpeg They came out great. I made pins from .250 drill rod and put nylon washers and "e" clips to hold them together. ( the original had tapped holes and screws in the ends of the pins) , I like this better. This and mounting these is the most critical and difficult part. I have ordered some steel plate to finish the trunion assembly...... More to come.
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#3
As this machine is the design of John Moran, I got his permission to do this build article. I will include photos and details of the build and prints for the changes I made that are not part of the original design. Anyone wishing to build this fantastic machine can contact John directly for details on those parts. The drill sharpener was featured in two issues of HSM magazine I believe , but Village Press has run out of back issues of the magazine.

With that said, I can get to building this project.
 

Billh50

Active User
H-M Supporter-Premium
#4
I managed to snag both issues of the magazine when I saw your original build. Just waiting to get a real milling machine before I attempt to make it though.
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#5
I managed to snag both issues of the magazine when I saw your original build. Just waiting to get a real milling machine before I attempt to make it though.
Yes, it is much easier with a milling machine. Although , there is only a small amount of milling to do. I did 90% on the lathe and drill press. If one has the means to mill the small parts on their lathe, a mill isn't even needed, especially if using mostly aluminum as I did.
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#7
I would need to get or make a milling attachment for my lathe.
I made a simple but good milling table for my south bend 9 before I had a mill. It was 8" X 8" X 3/4" thick.


Bill,
what kind of lathe do you have?
 
Last edited:

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#8
I am making some of the small parts while waiting for the ordered materials to arrive. I ordered a ER 20 Collet Chuck, A set of linear bearings, bearing rods , a diamond grinding wheel, and rod support brackets. I also ordered some steel pieces to make the sharpener.

While waiting for materials, I have made the trunnion supports and today I made the infeed screw for the collet block. It is made from a piece of .375 diameter brass rod knurled on the end.
Infeed Screw.jpg This is the print for the infeed screw.
turning screw.jpg Turning the brass rod requires a center to keep it from bending.

finished screw.jpg This is the finished screw with 6-32 threads on the end. The spring will keep the screw from moving when using the sharpener.

screw and spring.jpg This screw is almost three inches long overall and 2" of it is only .138" diameter.

I also started making the indexing knob.
knob.jpg It is steel, knurled For .500". I have to wait for the collet chuck to arrive to finish this part. It must be bored to be a close sliding fit on the collet chuck.
 

NEL957

Active User
Active Member
#10
Mark
As normal top shelf, with steel and the new changes are bound to be a much better sharpener.
Be well my friend
Nelson
 

Randall Marx

H-M Supporter - Premium Content
H-M Supporter-Premium
#11
Another build for me to watch. I love it and expect your usual very-high quality work! Your attention to detail is my favorite part of you builds. Thank you for once again sharing this build with us!
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#12
The two adjustable linear bearings came in today. They are a little over an inch square. They seem like nice quality, I'm impressed. All the parts are shipped for this project.
image.jpeg
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#13
Some of the steel came today for this project so I got busy on it.
image.jpeg The trunnion supports mount to a .250" thick ground steel plate 4" square. This plate does not have to be ground , but it just makes it a little more precision. It required some imaginative clamping to hold everything in position to drill and bolt together.

image.jpeg I drilled and tapped for 8-32 SHCS to hold the supports. I put the alignment rod, which is a piece of .250" diameter ground rod, through the trunnion supports to keep them aligned while drilling and tapping. I got one screw in each one to get it together and check alignment before drilling the other two holes. To align the supports on the ground plate, the right support is located even on the front corner of the plate. The other one will line up in position by the alignment rod.With the trunnion supports bolted to the ground plate ,the alignment rod should be able to be turned with your fingers.

image.jpeg The other two bolts are installed. It took patience and time to line everything up, but was worth the effort. The clearance holes for the 8-32 SHCS were drilled for "close" on size fit. There is only a couple thousandths movement when loose , but everything is lined up as close to perfect as possible.

image.jpeg With the trunnion supports installed and the alignment rod free rotating, the plate was clamped in the mill vise and the front milled for clearance of the grinding wheel. The distance milled out for clearance is 1.0" and goes back to the front of the trunnion support. The width is not critical, so I milled over leaving about 1" total where the other trunnion support mounts. ( There is a half flat on the center of the alignment bar which will be explained later.)
image.jpeg Next will be to drill and mount the outside trunnion supports that mount on the sliding base plate. Notice there are two thin nylon spacer washers between the two trunnion supports on each side. These are for clearance and serve as bearing surfaces for smooth operation.

image.jpeg With one bolt holding the right trunnion support and before drilling the left side, the ground plate is lined up square with the sliding plate. Then the left side will be drilled and tapped for 8-32 SHCS.

image.jpeg The outside trunnion supports are drilled and tapped and mounted with the same care as the inside supports. This completes the main trunnion assembly and is probably the most critical and difficult part of this build.

image.jpeg The outside trunnion support on the left side has a distance of .362" stamped on the top. This is the distance from the face of the support to the center line of the alignment rod. I put this there as a reference. If I choose to mount this Precision Drill Sharpener on my T&C grinder the face of this trunnion support would be lined up with the face of the grinding wheel to locate the unit for sharpening drills. I haven't decided yet if this will be a stand alone machine or be used with the T&C grinder.

image.jpeg
image.jpeg These two photos show the completed trunnion and sliding table. The next process on this will be to locate and drill the holes for locating the chuck and bolting the linear bearings to the sliding base plate.

The first machine I built was mostly aluminum ( as I had the material) and although it works flawlessly and does an excellent job, this unit made of all steel and much better precision is going to be a highly precision and sturdy machine. I am making subtle changes to Mr. Moran's design to try to make the machine the utmost in quality and precision. So far the minor changes are:
1.) The trunnion table is .250" longer to move the chuck a little farther back from the grinding wheel to allow more clearance when grinding the larger drills. This plate is 4" X 4.125" instead of 3.625 as in the original design. I found this to be desirable from using the machine I built previously.

2.) the outside trunnion supports are .250" higher. This raises the trunnion assembly slightly to allow the space for a different design angle setting gauge. Also this was needed if I wish to use the unit on my T&C grinder.

3.) The sliding base plate is increased in size to 6" X 8". This was done to accommodate the linear bearing system. By using all steel construction and ground plate, this makes a higher quality and sturdy machine.

These traits will be continued through out the rest of the build along with other minor changes to the other components to make this hopefully my finest build yet.
 

NEL957

Active User
Active Member
#14
Mark
Very nice and it will be so much better than the aluminum. All the work you have done on the mill is paying off now.
Be well my friend
Nelson Collar
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#16
Mark
Very nice and it will be so much better than the aluminum. All the work you have done on the mill is paying off now.
Be well my friend
Nelson Collar
Yes, Now that I have better and more tooling ( much of it I made) and more machines, I am rebuilding some former projects. While the originals work great and are well built, I feel I have the capacity to remake some tooling and make it more precision and more "professional" ( for lack of better words). As I do This, I intend to pass my earlier versions ( where I am building a complete new item) on to some deserving soul that will appreciate them. It will be a way of paying forward the blessings I am enjoying now.
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#17
Looking good. Do you take time off to sleep and eat? ;) Cheers, Mike
LMAO......... Actually, yes I do. Some have wondered how I do what I do. I have probably 10 hours in what I have made so far on this project. That is not a lot of time and your next question is how do I do so much in so little time. I think the main thing is I am usually working on a half dozen different projects at the same time. I work on a project until I need a part or material and go on to another while waiting for that material. This keeps me busy and I get a lot done because time is well managed without even trying. I work at a nice even pace and spend an average of about 5 hours a day in my shop. If I get tired , I stop and take a nap. If I get hungry, I stop and go out to eat or fix something in the kitchen, I only work as much as I am comfortable doing. Some days that may be 8 hours but most days are around 4 or 5 hours and some days I don''t even get to the shop. My shop is my escape from the world outside and the worry of health problems or any other problems. I relax working in my shop. If this ever ceases to be fun....I will quit it. ( another thing is I been at this for over 45 years. I know a thing or two).
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#20
I made another change to the drill sharpener. I made a new trunnion table that is 5.500" long.
image.jpeg
You can see the difference here. The old table is sitting above. The original design was built from parts that were on hand. I've got the idea to make the table longer for more support of the collet chuck. This way , The complete Chuck will sit on the table instead of hanging over the back of it.

image.jpeg
Here is the completed unit with the new longer trunnion table.
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#21
Another change will be the use of the type M collet nut and Chuck.
image.jpeg
This photo shows the difference in the two types of nuts.
image.jpeg
Because there is a difference in the outside diameter of more than .250", this will create a lot more clearance between the collet chuck and grinding wheel. In the original design there were a lot of instances where the larger nut would hit the grinding wheel. This should eliminate that problem .
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#22
I looked at many other builds of this drill sharpener and there are many variations using the same concept but with various methods of doing the same thing. I intend to take the best features from many different builds and roll them into one great machine. Another feature that I will change is the setting of the angles for the trunnion table. The original design used some simple blocks to set the angle. While this works just fine and is very simple, I saw another method I found interesting and it is a more solid setting that cannot move when set.
image.jpeg This method uses an arc in a plate that will have a clamp bolt with a handle to loosen and tighten the setting. image.jpeg I still have to make the clamp bolt, but I really like this setup. There will be an adjustable stop at the primary angle and another at the secondary angle. Another advantage of this setup is I can set any angle desired where the original design set the angles and they really weren't adjustable. image.jpeg The range of angles is adjustable from -5 degrees to +40 degrees.
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#24
I made the clamp bolt and the adjustable stops.
image.jpeg image.jpeg The rear stop is set at 8 degrees for the primary grind and the front stop is set at 25 degrees for the secondary grind. Everything works great so far.
 

NEL957

Active User
Active Member
#25
Mark
That is going to be better than top shelf. I like the improvements. Can not wait to see the finish sharpener.
Be well my friend
Nelson Collar
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#27
Mark, how did you cut the curved profile on the adjustment plate and the slot? Thanks, Mike
That was tricky!
I made the piece that gets the slot as a rectangular piece of .250 thick steel. I clamped it where it gets mounted and put a pointed screw where the clamp screw goes. I then raised the table to scribe a line where the slot goes. This was the only way I could think of to lay it out because the pivot point and arc are in a different plane. ( I couldn't measure it).I then put the piece on the rotary table and kept moving it until I got the tool to follow the arc when rotating the table. Once that was done, I cut the slot, moved over and cut the outside edge. I hope this helps.
 

FOMOGO

Active User
H-M Supporter-Premium
#28
Quote: I made the piece that gets the slot as a rectangular piece of .250 thick steel. I clamped it where it gets mounted and put a pointed screw where the clamp screw goes. I then raised the table to scribe a line where the slot goes. This was the only way I could think of to lay it out because the pivot point and arc are in a different plane. ( I couldn't measure it).I then put the piece on the rotary table and kept moving it until I got the tool to follow the arc when rotating the table. Once that was done, I cut the slot, moved over and cut the outside edge. I hope this helps.

Thanks for the explanation, that makes perfect sense. Cheers, Mike
 

mark_f

Global Moderator
Staff member
H-M Supporter-Premium
#29
I got all the linear bearing parts in so I got that set up.
image.jpeg I removed all the SHCS and replaced them with flat head screws on the bottom of the sliding table. This gives me a flat surface and won't interfere with mounting the bearings. In the above photo all the bearing holes are drilled and tapped.
image.jpeg The linear bearings are mounted with 6-32 SHCS.

image.jpeg The unit slides nicely and smooth. Also notice there is an adjustable bearing on the front and rear. I thought these would be a good idea, but now I think they are not needed. The idea was to put a little "drag" on the slide but it gets "jerky" when you adjust them too snug. The system works fine without them.

I will address a topic before someone brings it up. The linear bearings and grit from the grinding wheel. I know from using the previous sharpener I built that there is minimal dust when using a diamond wheel. I also usually put a small cloth on the table under the wheel to catch any grit, so in my opinion this won't be a problem. Then I could always make way covers.