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Drill and End mill sharpening machine

GaryLa

Plastic
Joined
Mar 10, 2015
Location
Los Angeles
Hello,

I have been researching drill bit and end mill sharpening off an on for a year. I have seen every piece of advice from "just buy new ones" to hand sharpening to various machines. I have a complete understanding of how it's done, but no practical skills with much more than occasional drill sharpening by hand with a bench grinder.

We are embarking on a production project which includes tens of thousands of drilled holes and some minor milling. I would hate to be throwing away drill bit after bit rather than just re-sharpening.

My preference is to buy nice stuff and take care of it. So, I'd like to sharpen bits every N-number of holes, instead of using a new one each time.

I have been looking at a pricey machine known as "Cuttermaster CM-01P". I understand it's ridiculous overkill, but I also don't want to spend vast amounts of time trying to acquire the finesse of sharpening drills and mills.

I had a Deckel SO or SOE years ago, but we only made single-flute cutters with it. I mostly watched.

What would the recommendation be to perform these sharpening needs -- without having years of skill already racked up?

Many thanks in advance.
 
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In my experience, the SRD/TDR drill grinders are the easiest and best for drill sharpening. They make several models, so you need to know what size drill bits you want to sharpen. You can learn the technique in five minutes and sharpen drills in less than a minute for each one, depending on size. They make attachments that claim to do split points and the ends of end mills, but I am not impressed with those devices. I would buy new split point bits rather than trying to duplicate the factory grind.

I have a Darex E-90 end mill sharpener that can do a good job on both the ends and sides of end mills, but I seldom use it.

So, consider the cost of paying your own people to sharpen tools versus sending them out to a shop that does nothing else versus buying new tools. Maybe you can set up the SRD/TDR drill grinder so that a machine operator can sharpen drill bits between operations. Grinding end mills, especially on the side, takes much more skill and time.

Larry
 
In my experience, the SRD/TDR drill grinders are the easiest and best for drill sharpening. They make several models, so you need to know what size drill bits you want to sharpen. You can learn the technique in five minutes and sharpen drills in less than a minute for each one, depending on size. They make attachments that claim to do split points and the ends of end mills, but I am not impressed with those devices. I would buy new split point bits rather than trying to duplicate the factory grind.

I have a Darex E-90 end mill sharpener that can do a good job on both the ends and sides of end mills, but I seldom use it.

So, consider the cost of paying your own people to sharpen tools versus sending them out to a shop that does nothing else versus buying new tools. Maybe you can set up the SRD/TDR drill grinder so that a machine operator can sharpen drill bits between operations. Grinding end mills, especially on the side, takes much more skill and time.

Larry
Agree 100% with larry

A simple machine for simple drills is not a bad idea.

Most guys will have difficulty getting the OD with the correct clearance on the Cutmaster.

if you can find a sharpening shop to do a good job for about 1/2 price likely that is the best choice.
 
Resharpening depends a lot on the size and type of drill bit. You have probably been told that a bit less than .25 is not worth resharpening. Since you haven't said what the depth or diameters are there is only so much advice to give. You will also learn that some manufacturers work better than others. Best way to evaluate the process is to check the drilled hole every x number of holes and chart the results. Then you have better data to make a judgement with.

Tom
 
Not sure messing about with end mills is worth the bother, plus you end up with undersized end mills. Drills might be worth it, but be sure you know how much time you're spending. If you're doing thousands of parts, you should be buying the best quality carbide drills you can get, in bulk, so you get a good price. That will affect the economy of sharpening. Sharpening might only make sense when looking at the single piece price of a drill, or if they're biggins.
 
Darex M5

I bought it new many years ago new, fast and precise. sharpen , split , modify any angle you want to......

Some on *bay right now.

This is not a Drill doctor...........think it was around $1200 new
 
Plus ++ on the SRD !! Dead simple to use ,and minimum practice to become proficient.I have successfully sharpened 1/16 bit with mine.
 
I have a 20+ year old Darex drill sharpener. Does a nice job. Small bits get tossed sometimes, but repeat jobs using a lot get sharpened in bulk. And when you are working into the night and need a stub drill? No problem. Different point angle? Web thinning? Very easy to do.
 
Thanks very much for the great replies.

It appears that Darex has discontinued the E-90 mill sharpener without a replacement.

It seems the replacement for the DrillGrinder M-5 model is the M-80. I'm going to look at that unit.

I do have a surface grinder and some fixtures, but it's CNC-controlled which I think makes it difficult to use for this. I considered getting an old manual one for sharpening, but then I remembered I didn't know what I was doing.

The holes we're drilling are 4.1mm, #21, and #7 mostly (90%).
 
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The holes we're drilling are 4.1mm, #21, and #7 mostly (90%).

Those are pretty cheap size drill bits. Presumably uncoated, since you would be grinding the coating off anyhow. Even at 10's of thousands of holes, seems like it would take a lot of saving $1 drill bits to pay for the grinder? Unless you are doing stainless or something exotic ... but then you would be running carbide?
 
..... I would hate to be throwing away drill bit after bit rather than just re-sharpening.
We all hate to throw away stuff that can be fixed or reused.
But there is time and money costs.
In this size in HSS I tend to toss them as the resharp time cost is more than new. I will say I hate to do it as it screams so wrong in my head.
Also know that they get smaller and the web gets thicker with each regrind not to mention belly or cave and will not cut the same.
Tens of thousands of holes is not hobby or home shop level.
 
GaryLA sir,
Here's what I use in my shop.
Drill Grinders from Oliver of Adrian : Since 1913
I have an oliver 600 and a model 21. The 21 will do up to 5/8th ( even though they don't advertise it as doing such). I can sharpen 30 small drills in 15 minutes without breaking a sweat. I really like that it is easy to change the geometry of the drills for different materials.. Really simple are the model 21's. The drill holders have a size range so as long as your drill is within that range you can sharpen it. You don't need a holder for every diameter.
I know this is no help for your quest to sharpen end mills but I hope you find it useful in some way.
Stay safe
Calvin B
 
I've been using a Black Diamond grinder for sharpening drills the last 5 or 6 years. It's a bit of an overkill for the volume I do but is easy and quick to use. I wore out a Drill Doctor Classic 750 in only a few years and didn't want to repeat the experience.

Black Diamond Grinders are expensive new, but can occasionally be found used for reasonable prices. The one I happened on is a model 65. It was built for a military contract in 1974. Unlike standard Black Diamond machines it has a 1/3 hp 3 phase motor. All those built for the commercial market I'm aware of have a 1/4 hp single phase motor. This one came from a National Guard repair depot. It was purchased new, but never used. Why they purchased it was beyond me. The building it was in didn't have 3 phase power so it sat unused in the corner until it was auctioned off in 2012.

The second owner bought it as part of a lot, and again had no intention of using it. It sat in the corner of his shop until about 2016 when the shop moved to a new location. He knew I was looking for a drill grinder and offered it at a more than reasonable price. It didn't cost me much more than a replacement Drill Doctor, and is 10 times the machine.

DSC09988A.jpg DSC09987A.jpg


ON EDIT: There's currently a Black Diamond BW_70 model listed on eBay for $450.00 or best offer. It looks to be an excellent machine and within the size parameters you need. It looks to be missing a few collets, but they aren't that hard to make.

Black Diamond Precision Drill Grinder with cabinet ,RPM 3400,,model BW-70, | eBay
 
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I just want to offer a counter opinion or completely different path really.
First I am assuming that at tens of thousands of holes you are doing this via cnc.
I drill tens of thousands of 3mm holes regularly and I get about 8,000, 3/8" deep holes in 17-4 stainless with a single $70.00 drill bit (thats .875 cents a hole).
I think sharpening drill bits is a waste of time and skilled labor. Your time, or an employees time is worth more than a decent drill bit. Running hss bits or even resharpend (read coating removed) carbide bits in production does not make economic sense in 2021.
 
My only experience was with “Brierley” drill sharpeners, I have to be honest it’s not the easiest to learn, however the results were faultless, and fast, I could do a small bin of drill bits in 40 minutes, each one identical.
If your going into bulk drilling ( we had a cnc sharpener also) I’d think of outsourcing, till the process is stable then look at bringing back by acquiring the right machine first time, darex xp16 was looking good, the one we had was the size as a fanuc robodrill with a price to match but took stuff up to 3”
Mark
 
I'll second the Black Diamond, I got an old style and restored it. Bought parts off Fleebay and can go from #80 to 3/4". I've split the point on a 3/64" drill with it.

full
 
The best way to have them resharpened is to accumulate perhaps 50 of a size and send them to a high-quality sharpening shop. The problem is length variance if that bugs you set up.
Good to layer them so ODs don't get damaged.
 








 
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