Interesting, also what I do when I am concerned about not marking the surface on breakthough is to put a rubber grommet at the drill end of the bit, acting as a cushion, works a treat
Just a warning on those Harbor Freight bits. I had some wobble and it was too late to return them. So if you buy them, take every bit out and roll them on a flat surface to make sure they're straight. I imagine you could bring them back for an exchange if you find one that wobbles.
Good video. I think the first lesson would be to learn to drill holes properly. Your bits will last longer and your holes more precise and cleaner. The Cobalt bits should not be used in a hand drill- the wiggling movements can snap them. Drilling steels/metals are best done with the cobalt- not aluminum. Use a lubricant and the bits will love you. Drill a pilot hole sized properly for the drill bit size your using- that 1/4" bit could have used a 1/8" pilot- though bits that small really may not need a pilot hole- depends on the material. Use a punch on the material to mark your drilling spot and to keep the bit from wandering and breaking. The bigger the bit, the slower the speed- aluminum likes faster speeds. The good thing about the cobalt bits vs the HF coated bits is the cobalt can be sharpened and not loose their hardness, where the coated HSS bits will loose the hard coating once you sharpen them and revert back to cheap HSS HF bits are made of. I have no use for those Dewalt pilot bits I call them. Using proper drilling methods, the regular grind bits are just fine. I will sometimes use a cheaper coated bit to start the hole about .010", then use the cobalt to finish- this prevents wandering. Control the breakthrough by backing up the material your cutting or you can snap the bit. Drilling through material too slowly will overheat and dull the bit- keep the bit pressure steady and make curls, not little chips.
And always use pilot bits for wood, pretty much exclusively, I can do just fine without Cobalt, I don't do a lot of drilling through steel, but I suppose if I were I out to buy a new set I would consider the Harbor Freight, especially at the price point of being the same as DeWalt
Yes Cobalt bits even when doing wood drilling if you do a lot of wood drilling or are going through Hardwoods high speed steel will wear out pretty fast because wood is abrasive that has mineral content. That is why saw blades have carbide tips.
I bought a cobalt bit to drill through my tow hitch. drilled through hitch and receiver just fine. then I let a girl use my drill. she snapped it almost instantly.
It’s definitely easier to break them if you let it wobble or angle in the slightest, but with care, m35 and m42 (5% and 8%) cobalt bits work just fine in hand drills. I have a stubby m42 set from snap-on that I use regularly with my 3/8 chuck right-angle Milwaukee drill, and have yet to break one. Usually drilling exhaust manifold bolts.
The more intricate the tip of the bit, the softer the material it was designed to drill through. Pilot bits are for timbers, 135 degree tips are for metals and stones. I manufacture aluminium and steel security screen doors for a living and go through about 5 bits a month, where as my coworkers go through x3 that amount in the same time span. Our boss is a tight ass so we sharpen and reuse old bits until they're no good or snapped, but its still so aggravating losing time on a busy schedule due to trying to sharpen a bit without a sharpener just a grind stone and patience, let alone when they snap! Regardless of the ore used or size of bit in the drills they all snap and all eventually lose their efficiency. I cannot wait for the days where I can make me doors with 1 bit in each tool without ever having to worry about swapping them over except when different sizes are required. Maybe a new metal all together or from meteorites. Maybe Isotopes of existing metals that have unusual properties like extreme density and tensile strength. Maybe diamond may become so common a resource in the future we can afford to make diamond drill bits, not just tipped. Using HSS and tin coated aluminium drillbits is a joke, especially when working with steel. I'd have to make straps for the inner edge of the frame of the door to hide the edges of a sheet of strong mesh, drilling through the tops, bottoms and both sides up to 100 times per door. If it's steel i'd be lucky to make a single door with a single drill bit, if it's aluminium I get about 2 - 4 weeks out of a bit and that's with resharpening in my own work hours when I should be pumpin out doors :/
The pilot points seem like a good idea and they are very sharp. The problem is drilling heavy steel. You'll twist the pilot point off before the main bit bites. This renders the bit completely useless. When they don't twist off, it's an awesome bit.
For super precise drilling into wood and plastic/thermoplastics, what type of bit would you advise besides carbide which I’m just not going to drop that kind of money on Bits. Would love to here your advise as my situation I drill to the .001 and it’s got to be exact and I can’t have walking.
If you want super precise holes than you have to drill them slightly undersized and then use a machine reamer to size them to exactly what you need. To ensure a precise location then you have to use a center punch to give a divot for the drill bit to start and on larger holes you would also want to Pilot drill. Meaning for a half inch hole in aluminum to be super accurate you would want to center punch, pilot drill, drill to just under half inch, then use 1/2 inch reamer, a four-step process.
Drill a pilot hole which is smaller diameter first it will make for less pressure and less chance for walking away from where you want the hole located. Especially when using larger drill bits.
The Cobalt is not a coating, it is a different alloy high speed steel with 5% Cobalt also known as M35 or co5, high grade ones are m42 or co8. Meaning you retain the Cobalt advantage after re sharpening
my experience with three different sets of those exact harbor freight bits you have is they will work for wood and aluminum but if you drill steel not hardened steel just plain 1/4" angle iron you will have to sharpen the bit 3 or 4 times before you just put it away and get a quality bit they suck when drilling steel but great for wood
@True WingChun if you cant drill through a piece of 3/4" plate with a 1/4" bit without sharpening and then use a 1/2" bit to open the hole up without sharpening then the bits are JUNK these bits are JUNK period end of sentence
The cobalt drill bits are machined at 135 deg for hard metal so are not ideal for aluminium hence your problem. Test again on steel and you will see the difference.
HI! for so many interesting reviews and a very good delivery I would like to see you using a better setup and better camera angles if possible! thank you!
Um, why do you have the handle of your drill at such an awkward angle? It was uncomfortable watching you do a simple drilling task: no pre-punch to help the chisel point move material, your hands moving all over, shaking from the awkward hand placement and muscle strain, and how you don't anticipate breakthrough at all... and especially then trying to compare the results. I'm not aware of where you learned your drilling technique, but I'm guessing that has more to do with the variation in cuts than the quality of these little bits. Your hands shaking around is probably the main cause of the gouging in the cut channel. Maybe try a drill press if you want to compare the results? I agree with one of the other commenters: don't use the cobalt in a hand drill, especially if you can't get the drill stable. I don't own either of these sets. I think they are both kind of pricey for what they are, and I'm not sure who they are aimed at (DeWart aiming for the DIYers who can't sharpen their drills? Professional wood workers who would rather just buy new bits when they get dull?), but I do own the other two HF sets (black oxide and titanium coated) and a more traditional set of DeWalts (among others). The trick is to look closely at the points. The Dewalt are way cleaner, nicely ground in a classic double-bevel drill grind with sharp, smooth edges.The HF bits are basically straight ground. You know, to save money by just not grinding a second relief cut on the face. They are rather uneven on the quality of their grinds too, depending probably on the age of the grinding material at the time of manufacture, some coarse, some almost mirror smooth. That said, I end up using the HF bits most all the time. I know how to sharpen a bit, so the ones I actually use have a nice, sharp edge.
This made me go through my titanium drill index from Harbor Freight, the Warrior branded ones, specifically the ones I haven't used or sharpened. Maybe the cobalt line is superior, but I wish I could post a picture. Four of the bits were literally reverse ground. The trailing edges, where the relief angle should be, were higher than the cutting edges. One bit was asymmetrically ground, with the chisel point off center. I could only recommend these for users who are experienced and skilled enough to think, "Why isn't this cutting?" visually inspect the drill and entirely regrind the point. I think most people watching this should skip the cheap drills and just get a well-made standard set.
there is a optimal drilling speed formula, based on the size of the bit and the material you are drilling. For example when using a 1/2" (12.7mm) HSS bit in plain steel you would want to be around 700 rpm.
I think that dewalt set contain cobalt as well. Cobalt drill bits have extremely smooth surface, cobalt not only makes harder the material, its refining the grain structure of the metal as well. And those dewalt bits never could be that smooth if theyr only made out from standard hss.
Valuable reveiw i was never impressed wit the Dewalt bits. Keeping a sharp edge over time ironically i installed Architectual Woodworking and drilled AOTA of MDF and Aluminum just like you used in your eveiw it was funny though because i did use. A Dewalt case that Coke’s real well to store all my drill bits inside but. It was a variety of Many manufactures and mostly HSS that i could easily dress up with a Jewlers file in the feild as needed
Way too much chit chat- get to the point. Soft 6061 is not a good test at all. Cobalt is made for harder steels. Do this test on 4041 steel and do 10 holes a piece.
drill bits break when you add side pressure (drill bits aren't designed for that). downward pressure shouldn't snap any drill bit. I'm guessing your free hand drilling or your drill press is out of round.
I agree and on smaller size is usually you are running way too slow small bits need to run at thousands of RPMs and pushing way too hard small drill bits don't drill fast you have to have patience. CNC machines can drill through steel and other metals amazingly fast because they run perfectly precisely and are perfectly regulated in the speed and pressure that they drive the bit with
@@CatusMaximus the opposite is true once you get up to 1/4 and larger holes, esp with cobalt bits. Slow speed, very high pressure, and lube is what keeps the bits sharp.
Interesting, also what I do when I am concerned about not marking the surface on breakthough is to put a rubber grommet at the drill end of the bit, acting as a cushion, works a treat
Just a warning on those Harbor Freight bits. I had some wobble and it was too late to return them. So if you buy them, take every bit out and roll them on a flat surface to make sure they're straight. I imagine you could bring them back for an exchange if you find one that wobbles.
what's a cheap but reliable way to find a truly flat surface?
@@Layariona peice of plate glass you can buy at Home Depot or some hardware stores
Good video.
I think the first lesson would be to learn to drill holes properly. Your bits will last longer and your holes more precise and cleaner. The Cobalt bits should not be used in a hand drill- the wiggling movements can snap them. Drilling steels/metals are best done with the cobalt- not aluminum. Use a lubricant and the bits will love you. Drill a pilot hole sized properly for the drill bit size your using- that 1/4" bit could have used a 1/8" pilot- though bits that small really may not need a pilot hole- depends on the material. Use a punch on the material to mark your drilling spot and to keep the bit from wandering and breaking. The bigger the bit, the slower the speed- aluminum likes faster speeds.
The good thing about the cobalt bits vs the HF coated bits is the cobalt can be sharpened and not loose their hardness, where the coated HSS bits will loose the hard coating once you sharpen them and revert back to cheap HSS HF bits are made of.
I have no use for those Dewalt pilot bits I call them. Using proper drilling methods, the regular grind bits are just fine.
I will sometimes use a cheaper coated bit to start the hole about .010", then use the cobalt to finish- this prevents wandering. Control the breakthrough by backing up the material your cutting or you can snap the bit.
Drilling through material too slowly will overheat and dull the bit- keep the bit pressure steady and make curls, not little chips.
And always use pilot bits for wood, pretty much exclusively, I can do just fine without Cobalt, I don't do a lot of drilling through steel, but I suppose if I were I out to buy a new set I would consider the Harbor Freight, especially at the price point of being the same as DeWalt
Yes Cobalt bits even when doing wood drilling if you do a lot of wood drilling or are going through Hardwoods high speed steel will wear out pretty fast because wood is abrasive that has mineral content. That is why saw blades have carbide tips.
@@CatusMaximus I'll go along with the hardwood part of that, that will wear down a normal drill bit
What is the difference between the Yellow Dewalt set & the Black Dewalt set?
From my expedience cobalt should be used in a stationary device such as drill press or mill
I bought a cobalt bit to drill through my tow hitch.
drilled through hitch and receiver just fine.
then I let a girl use my drill. she snapped it almost instantly.
It’s definitely easier to break them if you let it wobble or angle in the slightest, but with care, m35 and m42 (5% and 8%) cobalt bits work just fine in hand drills. I have a stubby m42 set from snap-on that I use regularly with my 3/8 chuck right-angle Milwaukee drill, and have yet to break one. Usually drilling exhaust manifold bolts.
@@colemanbonner they are do able for sure. The stubby bit def helps steady the bit specially in a hand drill
The more intricate the tip of the bit, the softer the material it was designed to drill through. Pilot bits are for timbers, 135 degree tips are for metals and stones.
I manufacture aluminium and steel security screen doors for a living and go through about 5 bits a month, where as my coworkers go through x3 that amount in the same time span. Our boss is a tight ass so we sharpen and reuse old bits until they're no good or snapped, but its still so aggravating losing time on a busy schedule due to trying to sharpen a bit without a sharpener just a grind stone and patience, let alone when they snap! Regardless of the ore used or size of bit in the drills they all snap and all eventually lose their efficiency. I cannot wait for the days where I can make me doors with 1 bit in each tool without ever having to worry about swapping them over except when different sizes are required. Maybe a new metal all together or from meteorites. Maybe Isotopes of existing metals that have unusual properties like extreme density and tensile strength. Maybe diamond may become so common a resource in the future we can afford to make diamond drill bits, not just tipped. Using HSS and tin coated aluminium drillbits is a joke, especially when working with steel. I'd have to make straps for the inner edge of the frame of the door to hide the edges of a sheet of strong mesh, drilling through the tops, bottoms and both sides up to 100 times per door. If it's steel i'd be lucky to make a single door with a single drill bit, if it's aluminium I get about 2 - 4 weeks out of a bit and that's with resharpening in my own work hours when I should be pumpin out doors :/
Harbor Freight bits are good for polishing...
The pilot points seem like a good idea and they are very sharp. The problem is drilling heavy steel. You'll twist the pilot point off before the main bit bites. This renders the bit completely useless. When they don't twist off, it's an awesome bit.
Can you show us how to re grind them and what you usefor it?
I just got m42 bosch set, the dewalt was less pricy but didn't include 1/2
For super precise drilling into wood and plastic/thermoplastics, what type of bit would you advise besides carbide which I’m just not going to drop that kind of money on Bits.
Would love to here your advise as my situation I drill to the .001 and it’s got to be exact and I can’t have walking.
If you want super precise holes than you have to drill them slightly undersized and then use a machine reamer to size them to exactly what you need. To ensure a precise location then you have to use a center punch to give a divot for the drill bit to start and on larger holes you would also want to Pilot drill. Meaning for a half inch hole in aluminum to be super accurate you would want to center punch, pilot drill, drill to just under half inch, then use 1/2 inch reamer, a four-step process.
Catus Maximus appreciate it. Yea reamers are common in my application/use.
If you want a very clean hole in wood or plastic, use a Forstner bit and cut from both sides to avoid tear out.
Drill a pilot hole which is smaller diameter first it will make for less pressure and less chance for walking away from where you want the hole located. Especially when using larger drill bits.
Do you lose the cobalt advantage once you have to sharpen them?
The Cobalt is not a coating, it is a different alloy high speed steel with 5% Cobalt also known as M35 or co5, high grade ones are m42 or co8.
Meaning you retain the Cobalt advantage after re sharpening
I always end up drilling stainles steal and hardened steel. I had to end up returning the Dewalt at Northern tools and ended up getting some cobalt.
WHAT IS THE MODEL NUMBER OF HARBOR FREIGHT COBALT
Pilot are for wood. Cobalt usually metal
Don't you see that Dewalt is actual cobalt? Pilot Point can be used in both wood and metal.
How about Drill Hig
my experience with three different sets of those exact harbor freight bits you have is they will work for wood and aluminum but if you drill steel not hardened steel just plain 1/4" angle iron you will have to sharpen the bit 3 or 4 times before you just put it away and get a quality bit they suck when drilling steel but great for wood
@True WingChun if you cant drill through a piece of 3/4" plate with a 1/4" bit without sharpening and then use a 1/2" bit to open the hole up without sharpening then the bits are JUNK these bits are JUNK period end of sentence
@True WingChun actually pushing down on the drill is not what causes heat at all. It is the speed. Drills love being fed.
So... just drilling aluminum? Why cobalt?
Those pilot point bits are boss in sheet metal
The cobalt drill bits are machined at 135 deg for hard metal so are not ideal for aluminium hence your problem. Test again on steel and you will see the difference.
nice review as always
Split points can be reground.
In aluminum high speed, light pressure makes the cleanest holes. I like 4000+ rpm drills (1/4" chuck, pneumatic). Cobalt bits all the way!
That's a good idea I'll end up making a video comparing different RPMs when Drilling in aluminum
@@CatusMaximus
I look forward to seeing that! Low speed high pressure for steels. Titanium is somewhere in between-bring lots of bits!
This is the video that brought me here, subbing was a no brainer.
I have those Dewalts. In metal, a slight angle can make the corners grab and tear the metal. I'm not doing something right. . .
TTP HARD drill bits are the best I have comes across, but they are $$$$.
HI! for so many interesting reviews and a very good delivery I would like to see you using a better setup and better camera angles if possible! thank you!
Um, why do you have the handle of your drill at such an awkward angle? It was uncomfortable watching you do a simple drilling task: no pre-punch to help the chisel point move material, your hands moving all over, shaking from the awkward hand placement and muscle strain, and how you don't anticipate breakthrough at all... and especially then trying to compare the results. I'm not aware of where you learned your drilling technique, but I'm guessing that has more to do with the variation in cuts than the quality of these little bits. Your hands shaking around is probably the main cause of the gouging in the cut channel. Maybe try a drill press if you want to compare the results? I agree with one of the other commenters: don't use the cobalt in a hand drill, especially if you can't get the drill stable.
I don't own either of these sets. I think they are both kind of pricey for what they are, and I'm not sure who they are aimed at (DeWart aiming for the DIYers who can't sharpen their drills? Professional wood workers who would rather just buy new bits when they get dull?), but I do own the other two HF sets (black oxide and titanium coated) and a more traditional set of DeWalts (among others). The trick is to look closely at the points. The Dewalt are way cleaner, nicely ground in a classic double-bevel drill grind with sharp, smooth edges.The HF bits are basically straight ground. You know, to save money by just not grinding a second relief cut on the face. They are rather uneven on the quality of their grinds too, depending probably on the age of the grinding material at the time of manufacture, some coarse, some almost mirror smooth.
That said, I end up using the HF bits most all the time. I know how to sharpen a bit, so the ones I actually use have a nice, sharp edge.
This made me go through my titanium drill index from Harbor Freight, the Warrior branded ones, specifically the ones I haven't used or sharpened. Maybe the cobalt line is superior, but I wish I could post a picture. Four of the bits were literally reverse ground. The trailing edges, where the relief angle should be, were higher than the cutting edges. One bit was asymmetrically ground, with the chisel point off center. I could only recommend these for users who are experienced and skilled enough to think, "Why isn't this cutting?" visually inspect the drill and entirely regrind the point. I think most people watching this should skip the cheap drills and just get a well-made standard set.
Good review
Thanks
2000 rpm?? isn't that too high?
there is a optimal drilling speed formula, based on the size of the bit and the material you are drilling. For example when using a 1/2" (12.7mm) HSS bit in plain steel you would want to be around 700 rpm.
I think that dewalt set contain cobalt as well. Cobalt drill bits have extremely smooth surface, cobalt not only makes harder the material, its refining the grain structure of the metal as well. And those dewalt bits never could be that smooth if theyr only made out from standard hss.
Some serious RPM! haha
AND ALSO THE MODEL NUMBER OF DEWALT
Valuable reveiw i was never impressed wit the Dewalt bits. Keeping a sharp edge over time ironically i installed Architectual Woodworking and drilled AOTA of MDF and Aluminum just like you used in your eveiw it was funny though because i did use. A Dewalt case that Coke’s real well to store all my drill bits inside but. It was a variety of Many manufactures and mostly HSS that i could easily dress up with a Jewlers file in the feild as needed
Way too much chit chat- get to the point. Soft 6061 is not a good test at all. Cobalt is made for harder steels. Do this test on 4041 steel and do 10 holes a piece.
Dewalt looks gòod
Why Could you not put the camera on the other side so we see the drilling action, instead of you blocking it with your hand ??!!
Waaaay too many RPMs.
Those harbor freight drill bits are junk I was snapping those bits off all the time and I was mostly drilling aluminum
drill bits break when you add side pressure (drill bits aren't designed for that). downward pressure shouldn't snap any drill bit. I'm guessing your free hand drilling or your drill press is out of round.
I agree and on smaller size is usually you are running way too slow small bits need to run at thousands of RPMs and pushing way too hard small drill bits don't drill fast you have to have patience.
CNC machines can drill through steel and other metals amazingly fast because they run perfectly precisely and are perfectly regulated in the speed and pressure that they drive the bit with
@@CatusMaximus the opposite is true once you get up to 1/4 and larger holes, esp with cobalt bits. Slow speed, very high pressure, and lube is what keeps the bits sharp.
Not an objective review. You based most of the review results on your "opinions" rather than scientific measurements.