End Mill Sharpening Attempt

ericc

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Recently, I was in the TechShop, which is a shared machine membership facility. Usually, there are some end mills in the mill box. They are often not in very good shape, but they do work a little bit. This time, there were only two. One had the end snapped off. It would still work for side milling. The other just had a burned up end. I thought it might be fun to try to see if I could sharpen the end mill by hand on the grinder. There was no dresser available, so the right edge of the wheel was a little rounded. The primary relief was ground at about 5 degrees with a slight angle in towards the center to form a dish. The resulting grind did cut, but it left a furrow down the center-line of the slot. Is this caused by not gashing the end mill correctly. These are kind of junk community end mills, so there is nothing much lost if they are goofed up a bit. By the way, it was much improved by the grinding session.

millcut.jpg
 
I ground some in my mill with a wheel with the 1/4" shaft mounted in the wheel. I used a v block and just turned it 180 deg., a 2 flute set the primary angle about 5-8 deg. and the secondary about 15-20 deg., it cut good. Set the mill spindle speed as high as it will go.
 
We have no techshop type facilities here but I think if we did I would pick up some of my own tooling and take it with me. The small amount you'll spend will make things easier and your projects will turn out much better. And don't forget to take them home with you.
 
As a result of the passing of time, one of my friends here in this small town, had to dissolve his collection of equipment and after failing to sell any of it, decided to "give it away". What happened was that he advertised, "If you come get it, you can have all of it". Included in this amazing collection of sharpening machinery was a Darex E-90, built exclusively for the purpose of sharpening end mills.

The machine is NOT all that complex in terms of its operation but is quite elegant in its design. While I am still a rank novice at its operation, there should come a time in the "NOT TOO distant future" when I would be willing to take on such a task in trade for a task I need...(yes, I like the barter system).

Once my skill has achieved a relative "journeyman" level I'd post again and you'll be welcome to send your endmill for proper care and sharpening...assuming you have not already done so...
Cheers,
Trim sends
 
One match fire, I also have a Darex e-90, got it for a little trade it is brand new it does take a little getting used to, I have the opportunity to buy a e-90 along with a darex drill bit sharpener(the kind that looks like a bench grinder) 2 Foley saw sharpener one for hand saws and one for circular. The gentleman told me I could have them for $500. What do you think.
 
The Darex E-90 sells new for about $2900 (on sale right now). The same company makes the "Drill Doctor" and I have two of them. I love them. Easy to use and quick as well as they work well.

The Foley saw sharpeners would be difficult to say anything about because I don't know the model numbers.
I have a 360, a 380 (router and drill/mill bit sharpener) SF 1000, SR1000, and SS 1000. I also have a 357 and 367. The 367 is the newest of the carbide grinders. I also have a few odds and ends, like a FB 225 scissor sharpener (which I love).

I have a 387 filer as well as the SF1000. I have 5 of the tooth spacing rods (can't remember the nomenclature,) two of the straight carrier assemblies, one crown carrier and one miter saw carrier.

I have used the SF1000 a few times, primarily to learn how to use it. Following the instructions is key.

The 387 has no motor but is so much like the SF 1000 that following the instructions makes it very simple to use by cranking it by hand...(in case the "lights go out").

The 367 got damaged on moving it to my shop but I've repaired it and have it set up and ready to start trial sharpening. I have some older carbide blades to "learn on". I have the 357 all ready to go but I need the "Hook and Top Clearance Chart" which seems to be critical to getting things done right.
Cheers,
Trim sends
 
We have no techshop type facilities here but I think if we did I would pick up some of my own tooling and take it with me. The small amount you'll spend will make things easier and your projects will turn out much better. And don't forget to take them home with you.

I'd go one step further even. A small portable tool box with drill bits, end mills, lathe bits, a scriber, combination square, center punch, micrometer, and ball peen hammer. This should make your work both quicker and more accurate. You'd probably be able to think of a few other small items related specifically to what yopu're trying to do.
 
Sounds like you nay not have removed enough of the 'middle' of the mill. I would not worry about keeping the center cut aspect of the cutter, if it is one, and 'gash' the center. It will work for every thing except making a fresh hole.
 
I understand the "gashing", but what type of wheel to do it with......especially for carbide?
 
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