Drill bits

[scotthh]

I've always grabbed whatever bits were around or bought a specific one if I needed it. But I'm tired of scrounging, and want to get some good, marked bits.

The first choice is how many bits, what kind of set? It seems there are a lot of 29 bit sets 1/16-inch to 1/2-inch by 64ths. Seems like a good idea and I'll have a wide selection for making holes.

Next, what material. They make cobalt, titanium, black oxide, and high speed steel (HSS). The manufacturers would have you believe the exotic materials hold their sharpness the longest and the black oxide one won't rust has fast as the HSS ones.

Some sets are Pilot-point, some are Split-point, some are a mix and some are a mystery. "Pilot Point tip starts on contact for clean, accurate holes and reduces lock-up on breakthrough." Is this just a marketing gimmick?

Finally, you have to choose a brand. Does this matter?

$50 DeWalt DW1969 29 Piece Pilot Point Twist Drill Bit Assortment with Metal Index
$27 Hitachi 728078 29-Piece Split Point Black Oxide Shield Drill Bit Set
$13 Stanley ST-04150 29 Piece 1/16-Inch to 1/2-Inch Black Oxide Twist Drill Bit Assortment

Each set is basically double the price of the cheaper set. (The DeWalts were $58 yesterday at Amazon by the way.) Are the more expensive sets worth it?

[ScottS]

If you want your drill bits to start accurately, without walking, center punch the spot before drilling. For large drill bits, you may need to center punch, enlarge the punch mark with a small drill bit (a "center drill" or combined drill/countersink is good for this), then drill with the full-size bit. I haven't tried pilot point bits, but haven't noticed much difference in split point and standard bits; they all tend to walk if you don't center punch the hole location.

If your primary use is woodworking, I wouldn't spend a lot of money on fancy drill bits. I've yet to see a drill bit of any type rust, but then again I keep mine in the house rather than the garage. Coatings may prolong the life of the drill bit if you frequently use them to drill metal. If your primary use is wood, an expensive coating may be a waste of money. If you cut both wood and metal, it's not a bad idea to have two sets of bits. Cutting through metal really tends to dull a bit, which will make it more likely to tear-out when cutting wood.

FWIW, I recently bought a 115-piece (#1-60, A-Z, and 1/16-1/2" by 64ths) Titanium-coated drill bit set from Enco for $56. They're imports, but the quality looks good. Of course, the first thing I need to do is put a size 'W' hole in 14-gauge stainless steel and I bought the 118-degree set rather than 135-degree  I also have a set of DeWalt bits that I bought 10-years ago which are still going strong. I've used and abused them and most are still in good shape...

[bigh4th]

I would also stay away from the cheap sets from places like harbor freight.  out of every set I looked at, at least 2 bits had a screwed up point on them.  They're cheap for a reason.

However, you may want to check the local flea markets.  My father got a screaming deal on a snap-on bit set from a fellow who bought them and wound up never using them.  got a 60 bit set for $15.  My dad isn't a snap-on man as he feels they're ususaly over-priced, but a deal is a deal.

Hope that helps.

-Harry

[Xiaou2]

 Harbor Freight Bits + Drill Doctor = Awesomeness.


 Really, unless a bit is totally FUBAR'd  its gona cut about the same
as any other bit.

 Once you start cutting steel - it will wear your bits head down
very quickly,  and thus ruining it in less than a 5 min use.
 I dont care if its the top of the line bit with the best materials,
and coatings.   Steel cutting will kill them quickly.

 To revive the bits,  get a  Drill Doctor kit.

 You can re-sharpen bits as if they were new - or better (with the
split tip method).    Bits that would normally be tossed after 5 min
of cutting thru a steel pipe..  now can be re-used hundreads of
times over.   Saving you money,  as well as time, gas, and the
environment and resources .

 If you break a bit in half.   No problem.  Drill Doctor can still
be used to revive it.   

 Once you got it,  you may never need to buy another set of
bits your entire life.  Pretty sweet if you ask me.

 Anyways, Im very pleased at the results of Drill Doctor,
and highly recommend it to anyone who does a lot of
drilling.  I only wish I knew about it much earlier...


(I have the 750x model)

[ScottS]

Once you start cutting steel - it will wear your bits head down
very quickly,  and thus ruining it in less than a 5 min use.
 I dont care if its the top of the line bit with the best materials,
and coatings.   Steel cutting will kill them quickly.

I'm sorry, but the idea that cutting through steel ruins drill bits in 5 minutes is just plain wrong. What ruins drill bits is running them through anything at the wrong RPM. The right RPM is particularly important when drilling through steel. But if you use the right RPM, the correct feed rate, and an appropriate drill bit (e.g. 135-degree point for stainless steel) your bits should last for quite a few holes before they need to be sharpened. A bit of cutting fluid doesn't hurt, either. I know the machine shop class I just completed managed to drill lots of holes in 1020 steel with only a few drill bits shared across the entire class...

[javeryh]

My wife wants to drill 1/2" holes in a pumpkin for Halloween.  Am I going to ruin my drill bit?

[bfauska]

Not if you clean it off afterwards.

[TroyO]

Yeah, I used to burn up lots of bits trying to drill steel until I figured out that going super slow is the ticket. My old drill press only went down to 640 (I think) RPM, and the new one goes down to 220.... HUGE advantage for metal drilling. Lots of feed pressure and slow speed works good for me. I usually get chips and/or a spiral sliver out when drilling that way. When I was burning them up I would get dust/filings.

Anyway, I have the 115 piece nitride coated bit set from Harbor Freight... http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=1611 I think it was this one, and it's worked well. I've broken a few, but it was all pretty much my own fault.

I drill all kinds of materials, plastic/metal/wood/leather/bondo/etc (But never a pumpkin) and they've done pretty well.

And, they are on sale again.... I might just go get another set and keep the old to replace lost/broken ones. :-)

[Xiaou2]

Maybe I should be more specific.

 Its one thing to cut thru a 1 mm plate of steel.

 And another thing to go thru a 4mm steel pipe.

 The tip is what does the cutting,  and does wear with relatively quick time.

 Yeah, slow is best.   Also, using the trick by drilling small holes
first, and progressively larger ones works best.

 Yet, after such an endeavor, the bits tips just arnt going to be the same.
They will cut much slower cause of the wear on them.

 Ok, so my 5 min wasnt quite accurate..     (well, depends on if
someone knew what they were doing the first times  hehe )   
But still,  the Drill Doctor is amazing, and well worth it to me.

 

[squirrellydw]

So the drill Dr is good?  Can it do all types of tips?

[Xiaou2]

Its Great

 http://www.drilldoctor.com/pilot.asp?pg=compare-models

 DRILL DOCTOR MODEL 750X

The DD750X shop model is designed for durability and has the flexibility required to sharpen the largest range of dull or broken bits-including split points and masonry bits. The DD750X also adds increased capacity, sharpening 3/32” to 3/4” bits.

The precision and accuracy of the DD750X makes this our top of the line model.

    * One chuck sharpens all sizes 3/32" -3/4".
    * Longer jaws hold bit more precisely and jaw guides eliminate jaw twisting on small bits.
    * New “Push to Stop” design on the drill point splitting port will not allow you to over split the bit point.
    * Adjustable material take-off allows user to change the amount of bit material that can be removed to further extend the life of your bits.
    * User replaceable diamond sharpening wheel design for simple replacement.
    * Cast aluminum point angle shuttle for added durability
    * Metal sharpening tube
    * New permanent magnet motor produces consistent power, regardless of speed or load.
    * Sharpens High-speed Steel, Carbide, Cobalt, TiN-coated and Masonry bits
    * Can sharpen 3/32” – 1/2” reverse-twist (left-hand) drill bits with optional accessory

---

  The higher models can make a Split Tip from any drill bit.   Its quite amazing, because
it will make your normal bits even better.  Less wander, and faster cut times.

 The 750X also adds the ability to alter the cut angles of the tip from  115° - 140°, as well
as able to define how much material you want to remove.

 Can sharpen High-Speed Steel, Carbide, Cobalt, TiN-Coated, Carbide-Tipped Masonry


 Check Amazon for good deals on these.   Thats where I got mine.

[ScottS]

The only problem is that drill bits are cheap, while the Drill Doctor is expensive... especially if you want the ability to sharpen any type of bit. Seems like you'd have to sharpen a lot of bits to justify the purchase of a Drill Doctor...

[danny_galaga]

Harbor Freight Bits + Drill Doctor = Awesomeness.

when i was an apprentice we did a few days in a fitting and turning workshop. one of things we did was learn how to sharpen drill bits properly. i can still do it now. you have to turn it in a 3 dimensional movement. i wonder if the drill dr does this?

[Kaytrim]

Yes it does the 3D movement.  Over the lifetime of the Drill Dr. you will end up saving money.  I have one myself and I have not had to buy any new bits unless they broke off at the end of the flutes.  The thing is that this only works with your standard drill bits not anything like spade bits, forsners or hole saws.

TTFN
Kaytrim