Drill bits

Speeds and Feeds are critical to all tool cutters. As does the materials you intend to cut.
If steel, does your drill or mill go slow enough?
Please don't make the mistake I made when I first got my SDs.
I figured that if I had a chuck which would hold them, then I could use them. Good results thought otherwise.
Took me a while to to set up to spin them correctly.

Additional thoughts:
Please observe that a chuck plus a drill eats up alot of clearance. I don't know what you are working with for machines.
What is your plan for sharpening? Hand grinding is great. But you may want to practice on some sacrificial drills.
These days I usually choose an MT if I have one in the correct size.

Daryl
MN
 
Hertel has always been my go-to for inexpensive, but quality drill bits. They used to be US made, but my understanding is that they are now (since MSC purchased the brand) made overseas. I haven't purchased any of the 'new' ones, but they've always given me good service.

Eventually, you'll find certain sizes that you use a lot (e.g. #7 - the tap drill for 1/4"-20). When you do, invest in Cleveland Twist or another very high quality replacement. That, at least, has been my strategy, and it's worked out rather well.

GsT
 
I have been buying these ten packs of 5% Cobalt bits off Amazon. I can't believe how much better they cut than straight HSS!




I highly recommend these!

I just finished a project with a lot of drilling and tapping. All of the holes started off with 1/8, 1/4 and 3/8 bits to do the heavy removal of steel and then were enlarged with my HF letter and number drill bit set. Since the cheap bits are only enlarging holes they don't dull like they would if they were doing the bulk of the stock removal.



From what I have read 8% Cobalt drills are harder than 5% and will last longer but they are more brittle and will break easier.
 
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Ultradog MN said:
Agree.
But he asked for advice. Along with several others, I gave mine.
Problem?
Click to expand...
No particular problem with the message. ;) I've got mainly Dormer now and the cheap drills I have left, are sizes I almost never use (weird how the cheap drills you end up with are the ones you don't use! :grin:).

I've found though, in 30 years of internet use (going back to newsgroups), that one liner, hard-line 'advice' posts are generally of dubious value to people reading a thread and tend to reduce the s/n of that thread. ;)

Eh, I'm not the boss of you though. :)
 
My strategy is/was to buy the 115 piece drill set from Harbor freight. This way I have all of the sizes when/if needed. The drills are not real good quality and some even need sharpening right out of the box. BUT the index they come in is nice as it lists both the common size of the drill as well as the decimal size of the drill. I find this very handy when I need a hole of a certain size and do not want to look it up on a drill chart to see what letter, number, fraction is closest. As I kill the HF drills I replace with quality name brand drills. This way the sizes that YOU used most will all be quality and you still have the full set for that odd job where you may need that uncommon size.

As far as what sizes are best for you, only you can answer that. It was mentioned above that a #7 is good have since it is the tap drill for a 1/4-20 thread, It is extremely rare that I would ever tap a hole that big. Most of my stuff is M3, or #4-40 and smaller. Others would never want to tap a hole this small. It all depends on what you will be doing.
 
Drill Hog has a variety of sets. They have a drill & tap (with index) which might be what you're looking for.

The best is to get them all, number, letter, and fraction. Even better if you can get them in screw-machine length and standard length. And while you're at it, get the M42 variety for double the price.

Buying drills is a surprisingly difficult task. Even figuring out which alloy is better is a project. There's lots of low-quality fluffy probably-AI articles online. A forum is your only hope! Somehow I found Drill Hog and have had good luck. I just ordered some replacements last night. I had been using a cheap keyless drill chuck that would occasionally spin a drill, despite all of my efforts to avoid this bozo situation. Someone turned me on to Llambrich chucks, which take a death grip on the bit. So now I'm replacing a few spun bits.
 
I have one of those super index sets with over 100 bits, made in USA, that I save as my "good" bits. These get used for precise work, drilling before tapping, and similar work. For everyday use, a Harbor Freight set, made in India, gets the nod. These have served well over the years. A Drill Doctor is used to spruce up the edge, as needed. Honestly, this cheapo set has earned my respect time and again.
 
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