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Thread: Home built end mill grinder
01-17-2012, 10:19 AM #1
Home built end mill grinder
Hey have any of you built an end mill grinder / sharpener. I thought about trying to grab one of the small Asian lathes and coming up with something. Just curious if anyone has done something similar.
01-17-2012, 10:28 AM #2
The key think you want is the ability to move fairly rapidly and smoothly, to a preset stop. This is for using a cup wheel for the end grind anyway. Then you will want to be able to set the relief angles for primary and secondary (again end grind). Grinding the OD is more difficult to some degree due to having to use a finger on the flutes.
Really I'd look for a used KO Lee tool and cutter grinder, you can use it as a surface grinder (kind of)for small jobs too. And you can have two wheels on it at once which you will need or want to gash the ends of the endmills.
01-17-2012, 12:42 PM #3
Advise and a hard won philosophy
I completely sympathize with your burning desire to create something very useful with nothing more than an inexpensive base and your enthusiasm. I suffer from that same form of insanity and have for over 70 years. I once dreamed of making a banjo from a toilet seat and a Jonnie mop.
In my opinion, there is no way to even approach the worth and value of a tool and cutter grinder at used prices, by your expenditure of time and money in that futile quest.
Even a tired but decently equipped machine that needs some TLC and is priced accordingly, will get you much closer to the machine of your dreams, with far less effort and expense and it's designers had a much firmer grasp of useful functions and solutions for pitflls than you and I do.
I understand that your needs are modest, a handful of dull endmils but there's not much chance that you understand the needs that you'll have for sharpening tools, not long after you complete the Frankenmonster cheap lathe-cum-tool sharpener. And by complete, I mean give up on trying to make it do what it never could have done well.
It took me a long time to grasp that what I do to make a living, even a modest living, pays much more than time invested in futility. Haunt all sources of the machine tools you desire, like Craigslist, 'til that revivable jewel at give-away price turns up. Carry it home and marvel at the brilliance of it's design as your knowlege is increased by what it has to teach you.
An old, heavy antiquated plain bearing Galmeyer and Livingston T & C grinder was recently offered in my locale, for less than that HF junk costs. He finally unloaded it for $100. Vastly closer to the final goal you seek plus much more that you don't know to seek yet. As it stood, it could well accomplish your current needs and with some TLC, provide much more, that you don't even know that you need yet.
IMPORTANT: 3 more tips from my experience. Never let "heavy" sway your choice. Heavy only affects you once, (or until you need to move again) but crappy/light will effect you every time you flip on the switch and that effect will be disheartened/pissed! Heavy usually means better or best.
And further, a cheap little machine sitting on a rickety old dresser, takes up as much floor space as a real machine that does useful, precision work, EVERY TIME YOU USE IT! Avoid years of daily disappointment.
Finally, I missed out on so many truly great machines at little or even no expence, (free) that it makes me very sad. Why? Because of crippling ignorance about one thing, electricity. I'd whine, "that's worthless to me, it requires 3 phase power." Until I spent less than $200 and a weekend on the little project in the pic below, I could not capitalize on the true bargains, industrial machines. Now I seek them out.
10 HP 3 phase rotary converter. Turns my household single phase power into industrial 3PH. True magic! A little more in the electrical cabinet out of sight above.
In my mid sixties, I hauled home 4,000 pounds of horizontal milling machine and accessories and moved it into it's resting place in my shop, by hand, with no danger or extreme effort. Just some thoughtful time and use of ordinary objects. Lot's of stories chronicling that sort of thing in detail on this forum.
My hope is that though there's little chance you'll give this much thought, that you'll remember it after several disappointments on the path you are now taking, the sooner, the better.
01-17-2012, 04:27 PM #4
"grab one of the small Asian lathes"?
the feature of a grinder/sharpener is precision and stability. without it grind by hand.
01-19-2012, 12:39 AM #5
I really like how you set up that phase converter!!!! Looks like a slick setup. I will look into the older tool and cutter grinders. I agree I would rather have something which was purpose designed however I have yet to see anything affordable. Maybe I will run across such an item.
01-19-2012, 05:26 AM #6
While I agree with the engineers above, there's nothing wrong with a bit of DIY
Some years ago I built this one using a motorcycle fork leg as the slide. Surprisingly,the main tube is ground inside and out and a MT3 ER32 chuck just fitted nicely into the end.
The slide is mounted on a vertical slide via a simple hinge (so the end mill can be moved to the next flute) and the V-slide mounted to a cheap X/Y 'milling' vice.
It worked ... sort of
01-19-2012, 08:50 AM #7
You, axkiker and I are cut from the same cloth.
I'm psychic, know how your thinking went Bill, let me show you:
I've got some dull end mills and need sharp ones.
I've seen the way that they are sharpened professionally, how close to that am I?
Got the main part, a spinning abrasive wheel, just need to hold the end mill against it, at the right angle, be able to feed it in precise increments, exactly the same for each flute, and the toughy, feed it axially with precision.....the real guys call that an air bearing, right?
Hmmmm, that little X Y table feeds in sorta' precise increments, probably good enough to make these end mills better. I'll have to figure out a way to revolve the end mill without changing that perfect XY setting until all flutes are the same, oooh, a hinge?
OK, those are some of the easy parts, lets tackle the potential game stopper, precision axial feed..... what revolves and slides in and out pretty solidly, thousands of times without failure...(gazing around while waiting for that eureka moment) what's that leaning against the back wall, mostly hidden by other pieces of metal...motorcycle forks?
Sure, it wont make the end mills new but they'll be a lot sharper than they are now, probably get rid of that brown color, right where I grind but that's no longer important, I'm now compelled to try it. ...and THAT last bit is where our insanity lies!
Just shows that you and I Bill, are closer to how this stuff works, than ax has gotten so far but we weren't born with it either. Our development is demonstrated by the fact that neither of us would have seen a cheap asian lathe as fitting any required function in end mill sharpening.
OK, enough fun, thanks for the kind words about the RPC axkiker, (you really need one) glad that I may have aimed you in a better direction, wish this forum had existed for me 50 years ago.... lucky you...
Ax, go here http://www.practicalmachinist.com/vb...-plans-101231/ and start with the first entry, Jim Rosen's elegantly simple 3 phase maker. When you've read the rest of the thread, go back to the forum Milacron started with that thread, Transformers, Phase converters and VFD's and really get into it. It is your key to the good stuff, the best at pennys on the dollar. You may have to do a little fixin' but save your build time for the way you dulled those endmills.
01-19-2012, 08:56 AM #8
Well, this one works well, but was a lot of work. If you can find a decent deal on a k. o. lee, or even a cincy#1 or #2 with tooling, i'd go that way. I've built attachments for this one to do taps, single flute co-sinks, bandsaw blades, radius tools, etc,etc.
shown here setup to grind flutes on endmills:
01-19-2012, 09:08 AM #9
01-19-2012, 10:23 AM #10I'm now compelled to try it. ...and THAT last bit is where our insanity lies!
Collecting dust under my bench is an old Black & Decker valve grinder spindle and the slide from a chop-saw...
Unless I can wangle a Clarkson Mk2 out of a friend's shed.
01-19-2012, 10:28 AM #11
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01-19-2012, 10:45 AM #12
One thing you may try for endmill sharpening is a Delta Toolmaker grinder. Depending upon where you live, they may be had for very litte out the door (sometimes a fraction of the cost of an asian lathe). At this point, these machines are very old, so you will definately get your DIY time. You will not get to build the entire machine, but you can think of it as a casting kit. You will have to make or repair a bunch of the little pieces yourself.
01-19-2012, 10:49 AM #13
Actually for grinding the OD's the air bearing fixture is the heart of it I suppose, the tool and cutter shop I worked in right out of high school we used a cobbled together thing to do the OD's, all you really need to be able to do is raise and lower the table to change the clearance angle for primary and secondary.
01-19-2012, 11:05 AM #14Actually for grinding the OD's the air bearing fixture is the heart of it I suppose,
01-19-2012, 11:30 AM #15
Doesn't look like you gave up a lot by using that bike part, very nice flute grind Bill! Sure, an air bearing would not have left the microscopic serrations but I'd be surprised if they hurt and might even be superior for utility drilling in mild material, as they look to be quite uniform. Besides, if the hole needs to be reamed, a perfect drill wont take the place of a reamer and flute grinding, of any quality, has already resized the hole.
You nailed the helical contour, so that part works great too. Yeah, I know, just follows the finger but that's all the expensive ones do. Nice looking machine and it works too!
01-19-2012, 11:36 AM #16
Well im a big fan of Delta / Rockwell equipment. So I may start looking around for one of those Tool Grinders. I currently use a Rockwell drill press and just finished fixing up an 11" Rockwell lathe which I really like. So it would only be fitting to add a Delta grinder to the shop.
Or I may try to tackle rigging up some sort of sharpener on my own just for shits and giggles. Usually when I have these ideas what I do is more determined by what I find at the current moment. LOL
01-19-2012, 02:00 PM #17
I spent quite some time building this one (a Quorn) over a number of years, not quite finished in the photo:
then when I finished it I bought this one:
01-19-2012, 03:37 PM #18
No one understands better than I, the excuses one can come up with for spending excessive time on a "better mouse trap", while only having a passing relationship with mice and none at all with building traps.
I've known several guys that turned down time and a half overtime to spend the time with their hobby. The only possible way a budding machinist can justify that, is if he just want's the machine. Got no dreams that require it, so it's like collecting butterfly's, can't eat them and no one will buy them, just goofy about garish bugs.
If you have a project that requires the machine tools, especially if you are like me and have deluded yourself that successful completion of this project will set you on easy street, YOU ARE WASTING VALUABLE TIME. Especially when you run the numbers on great used industrial units, going for less than the parts for your cobbled together pile that slightly resembles that industrial unit and it's available today!
Even if you are immortal, (I used to be) and time means nothing to you, put that energy into your real dream, might get lucky, if you start soon enough.
I'm 72, it took me way too long to figure that out.
Got no advise for you guys that are weaving butterfly nets......
Now about Phil, since he went ahead and bought that commercial grinder, I'll assume that he needed it, but went without it all those years. Been wrong before though......
01-19-2012, 05:57 PM #19
I have a little K. O. Lee B960. The grinder cost me almost nothing, the tooling to go with it was FAR more than the base machine... this is like a lathe, you can get a free lathe and spend a small fortune tooling it up if it comes naked.
For endmill ODs, air bearing fixture is definitely the ticket. Perfect results first time around. There is absolutely NO resistance or friction, so it feels like you are holding the endmill in your fingers, having it guided by an all knowing hand.
If anything, buy a grinder and put your creative energies to work making fixtures. Those are the expensive part, anyway.
01-19-2012, 06:41 PM #20
If someone is interested in a project, I have about 90% of a K.O. Lee air spindle head for grinding end mills. What's missing is the base with the tilt lever to move the end mill to and from the wheel. The original collets have been replaced by $150 worth of precision bushings (which is what I'd sell it for). The air spindle seems to work well. If interested, I can take and send a pix.