End mill sharpening.

[th62]

Sharpening end mills.
Ok, so I machined up a new mount for the new Ozito rotary tool. I made the mount to fit the flexible extension, it worked ok, but the cords running everywhere is a bit annoying, so, I’ll make another mount later on just for the rotary tool to keep the cords to a minimum.
This is my procedure for sharpening end Mills:
Mount the mill in the chuck and using a straight edge, get the end mill cutting edges horizontal, then make a mark on the chuck or pulley of the lathe, make another mark 90 degrees to the first and so on until you have four marks all at 90 degrees to each other, then set up some sort of pointer.
Next, mount the rotary tool in the tool post and centre the shaft of the grinding wheel and bring the grinding wheel up the face of the end mill, switch your lathe into reverse gear and start it up. Start up the rotary tool and face the end mill until the mill is flat. You can just spin the chuck by hand if you wish.
Once flat, place the grinding wheel in the centre of the end mill and grind a divet in the middle, rotating the lathe chuck to get the divet central, the divet edge should reach the inner edge of where the flute meets the middle.
Next drop the rotary tool down a few degrees, rotate the chuck until the marks on the chuck line up with the pointer and grind the rear most flute, rotate the chuck 90 degrees at a time, grinding each flute, just make sure you bring the grinding wheel to the centre of the end mill on all four flutes.
Next, brush the cutting edges of the end mill with a diamond honer. I have a couple of diamond plates I use. The end mill should be as sharp as you can get it and should cut leaving a no e shiny surface.
You can grind a cutting edge and a relief behind that if you wish, but I don’t bother.
I don’t have all the fancy gear, adjustable tool holders and what not, can’t be bothered. I’m also pretty slack, you’ll notice my centre pointer point is now flat. Do whatever works for you, I’m a manual machinist in the extreme, but it works for me.
I started making a video, but it would have taken three weeks to upload, so, you’ll have to just look at some stills.
I prefer two flutes for aluminium, as they don't gum up like four flutes do.

[DIYer]

Thanks th62! We've added your End Mill Sharpening Setup to our Sharpening category,
as well as to your builder page: th62's Homemade Tools. Your receipt:

End Mill Sharpening Setup by th62

tags: sharpening

[Jon]

Congratulations th62 - your End Mill Sharpening Setup is the Homemade Tool of the Week!

This is a nice use of a rotary tool and a solid sharpening technique.

Some more good builds from this week:

Air Blower by RCTURKA
Flat Bar Twister by orioncons36
Drill and Hex Wrench Extension by hemmjo
Coaxial Centering Indicator by Improvised DIY
Moxon Vise by Make Things
Circular Saw Cutting Guide by Didpoolhall
Hammer and Drill Combination Tool by My MiniCrafts
Mill Center Finding Pin by Improvised DIY


th62 - we've added your tool entry to our All Homemade Tool of the Week winners post. And, you'll now notice the wrench-on-pedestal award in the awards showcase in your postbit, visible beneath your username:



And, you'll be receiving a $100 cash prize, in your choice of Amazon (US-only), PayPal, or bitcoin. Please PM me your current email address and award choice and I'll get it sent over right away.

Nice work!

[Don42]

Many thanks for a very clearly illustrated writeup that I could read and understand in a couple of minutes rather than having to sit thru a 10+ minute video that spends a lot of time doing operations we've all done thousands of times -- measuring, drilling, turning, welding, making swarf. And yes, I really do need a way to sharpen end mills!

[th62]

Funny, I posted this on Home Shop Machinist and all I received was a heap of criticisms. I don't think a lot of people realise that this is simply a hobby, not something to sink thousands of bucks into. I'd probably receive nothing but criticism from those on Metalwork Forums also. Both forums are largely peopled by those who have lost sight of the fact that this is a hobby, and not everyone wants to spend thousands and thousands on the best tools available. I make do with what I have, mostly Chinese. Besides that I'd rather do than get a machine to do it for me.
Even funnier, these people have machines that are capable of making machines and yet rather than make them, they buy them???

[tonyfoale]

Many thanks for a very clearly illustrated writeup that I could read and understand in a couple of minutes rather than having to sit thru a 10+ minute video that spends a lot of time doing operations we've all done thousands of times -- measuring, drilling, turning, welding, making swarf. And yes, I really do need a way to sharpen end mills!

Hear, hear. A voice of sanity shouting out from the morass of 3rd rate videos that seem to have taken over here. I was going to write a post similar to yours but you did it better.
Videos have their place but in a forum like this they should be used only to elaborate on verbal and photographic posts which allow one to quickly determine whether a post is of sufficient interest to go and view the video.

th62's post was like a breath of fresh air. Full verbal description adequately illustrated with plenty of photos. That used to be the norm when I joined this forum. I have a means of sharpening end mills ( Homemade Tool & Cutter grinder (with a difference). ) so the content of this post was not directly useful to me but it was just so nice to see a well prepare post again. Far better than 20 mins of watching a large diameter bar being turned down to a small diameter bar.

[tonyfoale]

Funny, I posted this on Home Shop Machinist and all I received was a heap of criticisms. I don't think a lot of people realise that this is simply a hobby, not something to sink thousands of bucks into. I'd probably receive nothing but criticism from those on Metalwork Forums also. Both forums are largely peopled by those who have lost sight of the fact that this is a hobby, and not everyone wants to spend thousands and thousands on the best tools available. I make do with what I have, mostly Chinese. Besides that I'd rather do than get a machine to do it for me.
Even funnier, these people have machines that are capable of making machines and yet rather than make them, they buy them???

Fortunately, this forum is remarkable free of that sort of mindless criticism. Unfortunately that is not common elsewhere. In my experience those who criticise for no good reason are generally those lacking the knowledge or ability to do it themselves and therefore are not worth listening to. It seems to be some sort of weird macho thing.