View Full Version : end mill ginding-part4

09-21-2006, 12:26 AM
here are a few more shots,expecially for Jim Hannum.We aim to please:D.
A flat piece of 1/16th alum. plate has a slot with a half round end cut in it.After inserting the end mill ,the plate is put in the diagonal slot in the front face of the chuck.It is then turned until the tip of one cutting edge is against the plate.Then the grub screws are tightened to hold the endmill in position in the chuck.Thus at every 90 degree turn of the chuck in the v-block slide,a new edge is offered up to the wheel.


The full view of the grinding operation,with the grinder not running.
The table that the v-block sits on can be turned horizontally for the side angle if required,or can be tilted in the vertical plane to give primary or secondary angles.I don't bother with 2 angles on the smaller cutters,but will try it on a bigger one when necessary.


Hope that explains the mode of operation,Jim.
I must say,I didn't really think such a simple thing could work that well.I'm quite happy with the results.
I have managed to grind a broken end mill back to a useful life,even if i'll only use it for roughing.
Just as an aside,the blue piece used for the base is actually a cast iron bracket of an old bed,used to hold the spring frame onto the headboard.
Gave it a quick pass on the mill to ensure a 90 degree face,and there you are.Recycle,recycle,recycle:D.

09-22-2006, 12:33 AM
Matador, I'm not sure I understand the responce (or the lack of) to your GREAT post? I have never tried to sharpen a mill end cutter, but have always wanted to try! I think your Idea at the least deserves some responce from some of the regulars of this BBS or at least a thumbs up or down! I plan to try your idea, Thanks for the post!

09-22-2006, 12:50 AM
Matador, I'm not sure I understand the responce (or the lack of) to your GREAT post? I have never tried to sharpen a mill end cutter, but have always wanted to try! I think your Idea at the least deserves some responce from some of the regulars of this BBS or at least a thumbs up or down! I plan to try your idea, Thanks for the post!

I agree but spreading it over 3 and now 4 threads makes it difficult. Perhaps Matador could summarize it all up in one post or thread?

09-22-2006, 12:56 AM
I second that,great subject excellently done with nice clear pictures as well.Gotta give it a try,I've got nothing to lose but a drawer full of dull end mills.I hate throwing something away that still has some life left to it.I'm sure that I am not the only one with a collection of old end mills that could be put back into service.Thanks for the posts on the subject.

09-22-2006, 01:19 AM
If it take ten posts, rsr911, and it helps me and the rest of us to understand what he is trying to tell us, so be it! The man has a great idea and deserves our respect and what ever it take to get his idea across to us. Until some one proves him wrong, ( and I don't think they will ) let him do it his way. When some one comes up with an idea that "Makes and Saves" don't knock them, Please:D

09-22-2006, 01:59 AM
Christian,the reason I spread it over 4 posts is,that for some reason you can only post 4 photo's or other graphics(including smilies)in one post.
I too would have preferred one single posting.
To properly show the working of the thing,I felt it necessary to add more photo's.
I believe I mentioned somewhere that the item was featured in an old issue of model engineers workshop(issue 14),an English magazine.Most people on this board are unlikely to have access to this magazine,so i felt justified in posting it.
I'm pleased some people found it useful.:)

09-22-2006, 02:01 AM
I'm not knocking him, just suggesting why the replies are so few. I'm also thinking of the future, if this project was posted all in one thread it would be easier for others to find by searching. Also having all the info in one thread would mean that comments and suggestions would also be in that thread and the end result would be a VERY useful one. This is only a suggestion, I'm not criticizing the idea at all, in fact I think it's brilliant and perhaps that is why I so wish it was all in one place, so that more will benefit.


Just noticed Matador posted as I was typing my reply to lugnut.

Matador, yes you can only post 4 photos per post but did you know you can reply to your own post with more photos? What I'm saying is that you could have had 4 posts in one thread with 4 photos in each, then the whole porject is easier to follow and condensed in one place. Regardless of all that I love the idea and I'm going to try it, in fact I'm going to copy your posts into a Word document and save it on my hard drive for future reference. ;)

09-22-2006, 07:14 AM
Hans, I was away yesterday, and did not get a chance to respond. The functioning is clearer now, and I can see how it is set up.

I asked for the view of the grinding as there are two methods of achieving the cutter angles. One is to tilt the fixture, the other to raise and lower it with respect to the diameter of the grinding wheel, the tangent of the wheel determining the angle.

With a tilting fixture like yours, using a cup wheel and grinding on the flat face will give better contol of the angles. This requires turning the fixture 90 degrees to feed the mill into the end of the wheel.

A finer grit will also help the finished grind.

The fixture is nicely made, and will do a good job of sharpening end mills. To do the ends, a simple fixture like this is just as good as any other type.

Many of us gear heads are not computer types, and don't know all the ins and outs of outwitting the forums. I encourage anyone to present their work in whatever method they can. We'll figure it out.

09-22-2006, 07:18 AM
I'm going to do like like others have said, copy and save these posts. A great little project, and heck, maybe a way to empty the box of dull endmills....
Thanks for the good explanation and the photos.

Lew Hartswick
09-22-2006, 10:59 AM
I built a fixture to do this on a tool and cutter grinder some time ago.
Works pretty well and can do S&D drill bits as well , using several
flat angles in place of the curve on the end.
Now to see if I can post a picture here. :-)
Nope. Can't find any place to attach a pix.
How do I do that? I'll put it on my home page at Earthlink.

09-22-2006, 05:04 PM
Lew,please read the sticky post at the top of the general forum page,it has a very good expaination on how to include photos with your post.


09-22-2006, 11:08 PM
Matador, excellent work! There are only 4 facets of proper endmill grinding, so do not be dismayed by some of the comments. The only hard part of grinding an endmill , is the flutes. I will say by experience, the normal, HSM, will probably never get the flute spiral perfect anyway. Why do you think there is such large discussion about tool and cutter grinders? It's because MOST people do not understand CLEARANCES. Simple as that. Keep up the good work.