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Thread: School me on drill bits
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06-09-2022, 02:00 PM #26
The problem with many Ti and Cobalt bits is that it is just a coating, which means they can't be sharpened. Or well, you can sharpen them, but then the remaining coating is going to chip off once you ground a portion off and you're not cutting with the high dollar magic you paid for. Research what you're buying.
And these higher end bits still don't change the fact that you're pressing down with hundreds of pounds of force on a 1/16" diameter rod that can still buckle and snap. IDGAF what kind of steel its made of, abuse your bit drill bits and they don't last.Wait, how can we trust this guy^^^ He's clearly not DJSapp
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06-09-2022, 04:45 PM #27
M42 is a tool steel alloy, you can get M42 drill bits with a range of coatings including no coating from a supplier like MSC (who’s online catalog the first couple pages of might be helpful for OP) As said earlier, overkill if all you have is a hand drill.
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06-09-2022, 05:58 PM #28Registered User
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I was looking at videos about bit sharpeners and stumbled across this bit comparison. Pretty interesting and reiterates a lot of the points made in this thread about speed and force.
https://youtu.be/xgQeSrsAXgE
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06-09-2022, 06:41 PM #29
this was a nice comparison... I'm not a fan of Black Oxide as the material seems (generally) brittle and the bits are easy to snap. That being said, they resharpen nicely and are cheap.
M35 & M42 designation indicates the amount of colbalt (5% & 8%) in an otherwise alloy material.
Sharpening Coated Bits ( per DJ's post) can be sharpened but a rabbit hole matching the sharpening element (fine wet & dry stones - hardened metal fixtures - laser - waterjet) to the exposed leading (cutting) edge material (coating) the Bit is made up of. generally speaking, a more expensive coated Bit will have more depth to the coating.
IE: A diamond cutter can be re-sharpened many times which is just a diamond particulate coating (in 99% of cases) on a fixture.I am not in your hurry
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06-09-2022, 08:03 PM #30
The comparison video is the one to look at on You Tube. It discusses things like the weight pressure, the material, and the different brand bits. You pretty much have 3 types of bits. Black Oxide, Titanium (most are only coated titanium), and then cobalt- used for steel and harder materials mostly.
As pointed out, the method and preparation are pretty much as important as the bits.
There are also drill bit sharpeners out there. Drill Doctor and others that can help rejuvenate the bits that are no longer cutting through materials.
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06-11-2022, 07:56 AM #31
If you're drilling wood and accuracy and clean holes matter, get a set of brad point bits. The brad point keeps the bit from wandering when you start the hole and the spurs on outside make clean holes--at least on the side you're starting from. You'll still get tear out on the back side unless you back up the work or finish the hole from the back. These bits are usually not HSS and you can't use them on metal. You also can't use them to enlarge an existing hole.
If you do a lot of mounting hinges a set of self centering hinge mounting bits is worth it. These put the hole in the wood exactly in the center of the hole in the hinge.
If you are using keyless chucks use hex shank bits, even if you don't use a quick change chuck adapter. IME keyless chucks don't grip round shank bits well, especially the smaller bits.
Quality of the bit matters most in masonry bits. And if the chuck of your hammer drill jams and you can't get the bit out, tap the end of the bit with a hammer. The tip is a lot harder than the hammer so you won't ruin it.
If you have a wife don't buy expensive bits, or invest in a safe that only you know the combination to.
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06-15-2022, 06:11 AM #32
there's 2 small tips I can give.
get an automatic center punch, if you need to start a hole and the spot you drill needs to be exact.
and basics...dont use a large bit to start in dense material,,,using a smaller bit will get job done faster and easier, then progress slowly up in size (this is important when drill in plastic or pexiglass ,as those can crack easily)ski paintingshttp://michael-cuozzo.fineartamerica.com" horror has a face; you must make a friend of horror...horror and moral terror.. are your friends...if not, they are enemies to be feared...the horror"....col Kurtz
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