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On 2012-05-05, Lloyd E. Sponenburgh <lloydspinsidemindspring.com> wrote:


Lloyd, I am very interested, myself, as to
1) Whether one can do a good job sharpening dull end mills 2) How long does it take.
Keep us updated.
i
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Well, I committed to the payment, so I guess I'll be learning to do it! <G>
I'll keep you informed.
From one friend, he estimates less than five minutes to 'tune up' a slightly-dulled 3/4" 4-flute bit that is not chipped. I will find out.
I will have to invest in a measuring device to handle 3-flute bits, or I'll have to work up the math to figure the new o.d. with a micrometer after the flutes have been ground.
LLoyd
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On 2012-05-06, Lloyd E. Sponenburgh <lloydspinsidemindspring.com> wrote:

Keep us posted. End mills seem to be very cheap at Enco. Say, a 2 flute 1/2 end mill is $9.99, double ended. With carbide, though, economies would be substantial.
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Ig, one thing I have found is that it's worth the money to go with premium US-made endmills, even when you're talking about HSS.
I have several 3/4" and larger milling cutters 4" long. They are immensely expensive (per pound), and the Chicom cutters just don't keep cutting cleanly for about 1/4 of the time the good US cutters do.
It might be the grinding. If so, I'm about to learn an expensive lesson (one way or the other). But since these E-90 machines sell all day long (used) for more than $1600, I figure I'm pretty safe.
LLoyd
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote:

I was spoiled by starting out with Pratt & Whitney Stellite cutters. When those finally wore out, I got some plain HSS tools and they were used up in minutes. I couldn't figure out what was so different until years later I finally found out those P&W cutters were Stellite! Now, I only buy solid carbide in the small sizes (up to 1/4") and M42 and M57 Cobalt cutters in larger sizes. The Cobalt cutters last at least 3 X longer than HSS and only cost a few cents more most of the time.
Jon
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Of course, once you re-grind one, that advantage is mostly lost. The gullets are still coated, but the primary and secondary reliefs are not.
Lloyd
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message

Cobalt is not a coating; it's a premuim grade of tool steel that's been formulated with a higher cobalt content, for the purpose of increasing red-hardness and abrasion resistance.
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in

Correct; I saw "coated" when he wrote that. Cobalt alloy cutters and drills are more than "just a few cents more".
Lloyd
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message

Okay, just wanted to make sure you were clear on that..
BTW, cobalt end mills are a bit more difficult to grind, the word "tougher" being an apt description...spark color, pattern and intensity is also bit different.
Anyways--likely it won't take you very long to notice that, when sharpening, they actually do "feel" a bit different as compared to M2--after which point if you ever happen to unexpectadly encounter one, you'll probably realize it fairly quickly.
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Thank you. Again, good advice. I use 'em. I've never sharpened them.
Lloyd
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    [ ... ]

    That means that you will want a V-anvil micrometer. Note that there are two styles with different V-angles. One for 3-flute, and the other for 5-flute.

    And likely need a diamond wheel to sharpen them.
    Good Luck,         DoN.
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message

Lay it on a surface plate, touch off on the od with a height gage for a zero reading and then take another reading off of the flute. Now, double the difference and subtract it from the shank dia.
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in

Good advice, and simple. Thank you. I do other indirect measurements all the time.
Now, if the beginning of the _other_ conversation had gone this way:
LS - "Wow! I just scored on a tool I've wanted for a long time! yay!" PM - "Well, I've owned one for years, and it's saved me lots of money, but here's what it can and can't do..."
Instead of: LS - "Wow! I just scored on a tool I've wanted for a long time! yay!" PM - "Piece of junk. Dumb purchase. (Even though I own one and have saved a $100K with it.)"
then the rest of the conversation might have gone differently. It seemed to me that your only intent for responding at all was to try to crush my enjoyment of having bought it. Of course I would bite back. Wouldn't you, with the shoe on the other foot?
I just bought a used Solberga 2HP drill press with power-down, in very nice condition. I was happy about it. Was that a stupid purchase, too?
Lloyd
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On Sat, 05 May 2012 19:28:35 -0500, Ignoramus18788

Did you keep that Monoset you had a while back? I have one, its far more versatile for making custom tools. IMHO, custom cutters is the reason to have tool grinding abilty.
I've done a whole bunch of end mill re-sharp. its slow work, no way around that. I'm a cheap skate, but i don't work that cheap. For standard end mills, just watch fleabay for deals. As my son says, there must be thousands of machinists walking top quality stuff home from their job and taking what they can get.
Karl
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I sold that Monoset for $2,500.
The buyer showed up in a full suit, with a hat that had a feather in it.
In addition, he has two smoking hot daughters with him, who helped with loading of this monoset.
Regarding end mills, I agree with you, more or less. It is cheaper to buy new end mills, or buy them at auctions, for cash, or have Bob sharpen my endmills.
Bob is the guy who does T&C grinding and who sold me my warehouse building. He could not own this building due to real estate taxes. His 2011 tax was raised to $49,000 PER YEAR, and the only thing he could do is sell the building for whatever he could get. He sold it to me, and due to purchase price, my real estate tax was lowered to $21k per year.
He was already behind on taxes and could do nothing.
I strongly feel that it is unfair, but at least I am on the better side of this unfairness.
i
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[snip]

Sounds like there is an interesting story here. Why couldn't Bob get the reduction without selling?
Joe Gwinn
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I am not a RE expert. Here's what I understand. The county "thought" that his building was worth $670k. He could not prove to the county that it was not worth that much, without actually selling the building.
Since I bought it in an arms length transaction, I could easily prove that the building is worth the purchase price ($280k), because this is what I paid for it. The county accepted the price of the transaction as estimated value, and my taxes were reduced proportionally.
Of course, I had to pay 1/3 of the first year's reduction to the lawyers that I retained.
i
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Were there no other comparable sales nearby? That's the usual approach.

At this point, the County is legally cornered by state law. So sad.

This may be the key. Bob may have been unwilling to hire a mean-enough lawyer: 49000/3= $16,333. It sounds like a lot of money, but was repaid in the first year. But, this should not have been necessary.
Joe Gwinn
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It is very possible that there were not any comparable sales. Plus, it is easy for the county to dismiss them during hearings.

As far as I know, and I do know, he did hire a lawyer every reassessment, and was not successful. That info is publicly available, that is how I know.
This is why I strongly feel that it is unfair.
i
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As you noted elsewhere, it was 1/3 the difference, or $9K. And it was a contingency fee at that.

Yes. And Bruce Bergman probably cracked the code.
This is a big reason that northern industrial states are busily deindustrializing.
Joe Gwinn
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