Drill grinding test results

Philco

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Oct 3, 2011
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Recently Charley Davidson, one of our members here @ hobby- machinist acquired some tool grinding equipment to sharpen end mills & such. He also acquired a large industrial cincinatti drill grinding machine. He ask me to bring him some drill bits that needed to be sharpened in exchange for an honest opinion of how the drill bits performed after he sharpened them. I took him about 10 bits of different sizes to sharpen. Here are the results of two of the bits.
I started out with a 1.000 silver & Deming style drill first.Faced off & centered drilled then drilled a .250 starter hole.
I stopped the lathe in the middle of the cut. Notice that both flutes are cutting
I drilled about an inch deep & measured the ID with telescoping gauge. The bore measured 1.003. I'm totally satisfied with this taken into the fact of the length of the bit & the ( spring ) in the set up.
The second test bit was a #4 morse taper 1.250 diameter drill bit that is 12 inches long.
I went through the same sequence as the first test except I drilled a .500 diameter starter hole for this drill bit. I stopped the lathe to show that both cutting edges are doing equal amounts of work.
Again I drilled about an inch deep & came up with a smooth bore & only .002 over on the diameter.
I am very pleased with Charley's work & I would highly recommend that if you've got some dull bits kicking around you're tool box to contact Charley through a Personal Message. I'm sure you will be satisfied with the quality work that he can provide.
Phil

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Thanks Phil, glad they worked as they should and glad you are happy. I still haven't got a total price sheet done for sharpening and I need to order so more wheels for my Tool grinder before I do some free end mills for some members & friends. You did a nice job on writing the review and showing pictures. Thanks for taking the time out of your busy schedule.

Thanks Charley
 
That's some even cutting on that bit!

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Lets see some pics of the machine that did the sharpening!
 
It's a Cincinnati drill grinder Simple in design yet somewhat complex (Sounds like a wine critique)

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