Drill Bit Advice

[reible]

As I slowly trudge forward on setting up my workshop at our new house, I mounted one of my 10E's on the wall as a dedicated drill press. I then came to the realization that have a large mish mash of old drill bits of various types and sizes, mostly from years of house repairs and remodeling, but that I would prefer to start off with a more organized assortment of bits more appropriate for wood working. So I'm hoping for some advice on the types of bits I should get, input on quality differences I should be aware of etc. In terms of what I'll use them for, once the shop is up and running, I will be making toys and gifts, wood turning, and some cabinetry and furniture making etc.

Hi,

I'm assuming we are talking wood shop drills.

I have no idea how much money I have invested in drill bits over the years but it would be a sizable amount. Unless you have a large pot of money at your disposal it would make since to add drill sets as you need/want them over several years.

Most sets come with bits that may never get used by most people, I like to share the wear by using bit slightly larger/smaller when possible. Bits like 1/8", 1/4", 3/8", 1/2" tend to be the more used sizes.

Sets can come in steps of 1/8", 1/16", 1/32", 1/64" of course you get more bits each time you up the step count, and more bits means more cost. If you can by the best you can at the time. And start with fractional twist bits.

A set of brad point bits will be needed. They will cost more but give better results in wood. They do no give flat bottom holes so you could go to the for Forstner bit set before or after the brad point bits. These bits will cost you but in some cases it would be pretty difficult to do the job without them. If you go to say 1" dia then add to the set as you need the bits is a good idea, larger bits get expensive so buying a set might be prohibitive.

If you want to do some quick and easy drilling on less quality or hidden holes then a set of spade bits is a good idea. In most cases you can get a smaller set for cheap.

Depending on what projects you tackle you may want a set of numbered bits, and lettered bits. If you start some metal working you will need to start getting serious with bits.

Metric bits I don't find much use for but I have a couple of sets that I got for working many years back. Since retiring I think I've used them less then 10 times.

A few other drill related purchases like a center punch and countersinks will need to go to the head of the list. For metal a automatic center punch would be a good addition.

A good set of stepped drills come in handy when working with thinner metal projects. I've seen cheap ones but I would avoid them.

This is of course an overview.

When I worked in a machine shop (lots of years ago) drills less then 1/4" were replaced when worn, bits up to about 1" were hand sharpened and bits larger then that were most often sent out to be done. I tend to think along those lines even now. Small bits are hard to sharpen and cheap to buy. Mid-range bits can be done by hand and I have no large bits.

Ed

[wa2crk]

Any metallurgists here? I have heard that HSS can not reach a high enough temperature to lose its temper by grinding. HSS is tempered at a much higher temp than regular steel. Any one know for sure? I would like to get an answer from a real expert.
I still think that a Drill Doctor or something similar is a good investment. I have had drill bits right out of the box that did not have the cutting edges cut equally. The Drill Doctor made the cutting edges symmetrical and the drills performed better. Just my 2 cents worth.
Bill V

[Ed in Tampa]

I think my question got lost.

If I go to the store I find

Regular Steel or no label?????

High-Speed Steel (HSS)

Titanium coated HSS

Cobalt steel

My question is Cobalt steel drill bits worth the increased price? How about the titanium. I was told the Titanium is just a coating and it comes off and you are left with a HSS drill bit.

[JPG]

I will leave that question for the experts, but feel a need to clarify terminology.

Heat treating involves both hardening and tempering.

When hardened, steel is typically brittle(thing files).

Tempering decreases the brittleness as well as some hardness.

Tempering is done at a lower temperature than hardening and under controlled cool down(compared to quenching).

When a tool 'loses its temper', is is because the temperature has attained the 'softening' range, but cool down is rapid(relatively speaking).

Then there is annealing which is the opposite direction from hardening.

IIUC HHS is tempered at a higher temperature and that allows it to be hotter when being used without loosing hardness.

[terrydowning]

As for the Original Post re:recommended drill bits.

For smaller holes.
I have a set of brad points for clean entrance holes in wood these seem to help a bit with tear out on the backside as well.

I have several sets of regular steel (jobber) twist bits I have accumulated over the years some of these are the "Titanium" (gold colored bits) I see no difference in performance between the two sets. nothing beats proper technique

I have a small 29 piece set of HSS bits I use for drilling steel

For larger holes:

I started with spade bits and hole saw (they come in the inexpensive sets)
I upgraded to a set of Porter Cable forstner bits I got at the big blue box store (They were relatively inexpensive and work nicely.)

Secrets I have learned for successful drilling
1. Use Sharp bits
2. Use a sacrificial backer on fibrous materials to reduce/prevent tearout during through drilling.
3. Use a center punch and sometimes even a starter bit on harder materials this can help even on wood or plastics especially if it's a larger hole.
4. Don't be afraid to step drill for larger diameter holes. Use Jobber bits only for step drilling. Step drilling with brad points or forstners is an exercise in frustration and futility.
5. TAKE YOUR TIME drilling develops tremendous heat especially if the bit is getting dull use slower speeds and stop to allow the bit to cool.

I am brand agnostic when it comes to drill bits. I have bits ranging in age from nearly new to older than I am form various manufacturers and I really can't tell the difference in performance.
IMHO It's proper technique and sharp tools that make the difference in drilling.

Tampa - Ed

To answer your question re: cobalt
For wood working it's an extra expense. I have the following types
Regular tool steel excellent results in wood and non ferrous metals, not so good for steel.
HSS does the job on most items. Take your time with a slower speed and lots of lubrication for steel.

Titanium Coating is just a coating (Looks like gold) that make the bit slicker as soon as the coating wears off either from use or sharpening your're back to using whatever the base metals are.

I have no experience with cobalt bits so take the following for what it's worth (Not too much)
I hear that Cobalt drill bits are great for harder steels (Like drilling out a grade 8 bolt) and I'm sure it would do great for wood as well. Personally, I don't think it's worth the money as I mostly drill wood and non-ferrous metals. I do have a set of HSS for the occasional steel drilling I need to do.


Hope this helps

[dgale]

Thanks for all the great input from everyone - it is very helpful. I have several sets of twist bits from over the years, most missing at least a few bits that broke or were lost. I do have one nice set I inherited from my Dad in a wood box - I save those for woodworking and use the others on random other stuff where I'm less concerned about the results. I also have the 5-piece SS brad point bit set (1/4", 3/8", 1/2", 5/8", 3/4" IIRC), all of which are unused or minimally used. Other than that, I have a few sets of spade bits, most of which need some rust removal and likely some sharpening. So sounds like I should consider a set of Forstner bits and otherwise will just buy additional brad point bits as needed to fill in missing sizes. It sounds like I'm not hearing any overwelming preference on brand or quality of Forstner bits (?) - I'll probably just start with a basic set of seemingly suitable quality and then add to it as need arises.

[newportcycle]

I think my question got lost.

If I go to the store I find

Regular Steel or no label?????

High-Speed Steel (HSS)

Titanium coated HSS

Cobalt steel

My question is Cobalt steel drill bits worth the increased price? How about the titanium. I was told the Titanium is just a coating and it comes off and you are left with a HSS drill bit.

You were told correctly the bits are typically HSS coated with titanium nitride. The coating will extend bit life by a factor of 3 or so, if your not going to resharpen, pay the little extra. If your going to buy a drill doctor, go with HSS and sharpen as frequently as necessary. Cobalt drill bits contain higher levels of cobalt alloy in their mix and hold edges better at higher tempratures such as you would encouner drilling hardwoods or metals, as for durability drilling wood i havent seen any numbers on wear but would expect similar to HSS.