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Drill bit sharpener or new bits?

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pfarber

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Any thoughts on buying something like a Drill Doctor for re-sharpening bits or should they by thrown away once dull?
 

BJC

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This is a joke, right?



BJC
 

Pilot-34

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Do both!
As long as you have plenty of sharp bits on hand you will do a excellent job with a drill doctor.

If it’s your last bit you’re going to mess that thing up so bad it’ll never recover
 

Hephaestus

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Depends on the bit.

But with the proliferation of cheap Chinese HSS bits even the tool cribs treat them as 1 time use disposable "shop supplies" safety officers would have you strung up if they caught you sharpening one.

But my favorite 3/8" HSS bit is now under 2" long it's been sharpened thousands of times.

Those under 1/8" sizes especially if they're chinese sourced - definitely one time use.

I ran across a split tip sharpener once - I'd really like to get one for my tool hoard :)
 

pfarber

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I have at least 3 big box stores (hardware)near me and i can guarantee that none of them would have 'rivet sized' bits in stock.

My concerns are:

Is there anything special about the bits that a sharpener would not be able to handle?
For people that have done a metal plane, would the $80+ cost of a sharpener have a ROI? Or do you not use enough bits that need sharpening? Say at $10 a bit, would I dull 8+ bits or not?
If someone has used a sharpener, were the bits good enough for precision AC work?
 

cvairwerks

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Buy your bits in bulk from one of the better known suppliers, such as MSC, McMaster-Carr or others. Stay with the better brands such as Cleveland. You can’t recover the cost of a decent drill sharpening rig when doing a single aircraft. Look at the cost of a Darex or Black Diamond sharpener for a cost idea.
 

stanislavz

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I did fire one worker for breaking dull bits in place of sharpening them or placing to a box of dull bits. We have one skilled older men, who was sharpening drill bits by hand in benchtop grinder, at the rate of 20-30 seconds per drill.

It is not a big deal to sharpen it, just take our time to learn it.
 

KirbyK

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I work as a machine repairman in a machine shop. I own a drill doctor and it's great for resharpening carbide drills on down, when the spiral or rate of twist is common. When it's not, toss the bit or if it's a bigger size sharpen by hand. Love my drill doctor.
 

dfunnemark

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I splurged and bought a 29 piece set from Drill Bit City (wintersdrillbitcity.com) after I had previously purchased some individual bits from them. The bits have lived up to the claims on the website. I try to avoid abusing them, but when cobalt or other bits don't work, I go to the good ones. Never failed.
 

pfarber

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8 minutes 43 should be enough.
Watching a guy that's got thousands of rounds of practice is of no value. He basically runs the bit over the wheel and says 'look! it sharp!'.

While its an impressive demonstration of skill, its completely useless as to HOW to do it.

Seeing that most bits are sub $5, I think for a one time build my best option is to buy in bulk. I don't need bits that often to justify a $100 bit sharpener.

And yes, I was taught how to dress bits as a Mechanic. We had a gauge we used to get a consistent tip angle (otherwise it walks and cuts like crap).
 

Daleandee

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I just bought a handful of the numbers I needed the most of. Make life easy on yourself. Drill bits ain't that costly.
 

Geraldc

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While its an impressive demonstration of skill, its completely useless as to HOW to do it.
I have been sharpening drills for years because most of the ones I used were large and expensive.When I was shown the technique in the video I found that I could sharpen drills quicker and better.
 

pfarber

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I have been sharpening drills for years because most of the ones I used were large and expensive.When I was shown the technique in the video I found that I could sharpen drills quicker and better.
One of my initial dilemmas was: buy expensive coated drills, or $2 HSS.
Next was, buy 2-3 HSS and sharpen, or buy 5-10 of each and throw them away.

Doesn't grinding a bit remove that expensive coating making it little more than HSS???
And coated bits are way to spendy... $10-20 each vs $2 for HSS. At most you'll drill 2024-T3 or a 6xxx series... would HSS really have an issue with this metal?

Right now I don't see the ROI for a sharpener, or in spending the time to learn. I could still bugger up a bit and make out of round holes meaning rivets would need to go up a size... muh purrity airplane won't be purty.
 

Angusnofangus

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And coated bits are way to spendy... $10-20 each vs $2 for HSS. At most you'll drill 2024-T3 or a 6xxx series... would HSS really have an issue with this metal?
HSS works just fine for 2024 or 6xxx series aluminum. You should get lots of holes for one drill bit. When HSS is too dull to drill 7075-T6 well, it will still drill 2024 fairly easily.
 

thjakits

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Panama, Rep. of Panama
Hi all,

....I think at the end it comes down if you "...need to have a drill bit sharpener" - if you don't feel the need - you don't need one!

I am just bringing my Drill Doctor 750 online....:rolleyes:

The problem with the Drill Doctor is - supposedly - really small sizes are not going too well....

I remember in Engineering School we had a beautiful bit and mill sharpener - but can't find that beauty anywhere!!
Every angle adjustable to the finest decimal! Special stones!

By any chance, does anyone know of a fixture or grinder/sharpener for SMALL bits?? like 0.5mm to 4 mm??


Cheers,

thjakits
 

cvairwerks

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A Black Diamond sharpener only goes down to a #70, and it’s a $9000 unit. A Micra10 will do it, but I couldn’t find a price on one, even a used one. I suspect that for doing microbits, you are going to be close to a Black Diamond grinder price for a used one. You couple probably buy a new Lyc/Con for less money than a new sharpener.
 
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