Recommend a good quality large size drill bit set

[fried1765]

I have many sets of high speed drills. I know none of the sets were over $80. Purchased from local hardware stores. I use Drill Doctor to sharpen them. Took a while to learn but now I can get all but those under, about 3/16", really sharp.

I have larger bits for both wood & steel. Purchased individually - not in any set. Each for a specific need.

The drill doctor is a good tool, but it does have a learning curve, and will only sharpen bits to 3/4" (I have a DD).

The least expensive bits are high speed steel - HSS.
There are Cobalt COATED bits, which as the Cobalt name suggests, are supposedly coated with a very thin Cobalt coating...don't waste your money on these.

True Cobalt bits are either M35 or M42.
The M35 bits contain 5% Cobalt, while the M42 bits contain 8% Cobalt.
As you might guess, the M42 bits are the better ones, and cost a bit more than the M35.
Both of these style bits are WAY better than the HSS junk sold at the big box stores or HF.

I have two sets of Molybdenum M7 bits up to 1/2", and some random M7 bits in larger sizes up to 1-1/4"
I buy Molybdenum M7 bits from Drillhog.com, and they are also sold on Amazon.
I feel that the M7 bits are equal to the Cobalt M42 bits.

M35 and M42 Cobalt, and M7 Molybdenum drill bits, are all vastly superior to the purported top quality brand of any high speed steel bits!

Quality drill bits are worth every penny, in my opinion!
Cheap drill bits are a source of frustration.

While not usually Cobalt or Molybdenum, at least a small set of left hand drill bits is also a necessity in my opinion.

 

[LouNY]

The set I have currently is a lot like this one. Probably about the same initial price and quality. Even looks like the same box.

https://www.northerntool.com/shop/tools/product_200626793_200626793

How hard is it to re-sharpen bits like these?

Rob

I have the same set of bits.
I have resharpened a few of mine, free hand on a bench grinder with a fine stone.
The best reasonably priced cutting fluid that I found and use is a blend of cheap ATF and diesel fuel,
about 2/3 ATF or a bit less and the balance #2 fuel oil, it does smell a bit.
Using this fluid and the slowest speed I can get on my drill press ( a small 1hp milling machine)
if I can get a nice spiral curling up the hole is going to be good and the bit last.

 

[Sawyer Rob]

I have several drill presses with 1/2" chucks.
Rob

So do I, but the problem is, most of them don't go slooow enough to drill BIG holes, but this one does,

So it's the one I use for drilling big holes,

SR

 

[BigBlue1]

OK, I could buy a set of those M7 Drill Hog bits.

Does anyone have a recommendation for a good drill RPM speed chart for drill bit sizes and metal types? I did some Googling but there is a lot of other info that seems more prevalent (surface feet per min and feed speeds) which doesn't help my little brain with RPM. I do have a drill press that can go pretty slow (at least as low as 300 RPM) but need to know what I'm targeting.

Thanks,
Rob

 

[Big Barn]

100 RMP would be nicer, Rob. And a good drill table vise and clamping accessories.

Don’t worry about specs for feed rate. Use the advice already mentioned concerning watching the chip.

 

[downsizingnow48]

Somebody above mentioned Champion hole cutters. You should give that a careful look. They are not just "hole saws". I use them too. They are excellent for what you seem to want to do. Accurately sized round holes with your drill press or hand held if need be.

CT7 5 Piece General Maintenance Hole Cutter Set

 

[Big Barn]

Somebody above mentioned Champion hole cutters. You should give that a careful look. They are not just "hole saws". I use them too. They are excellent for what you seem to want to do. Accurately sized round holes with your drill press or hand held if need be.

CT7 5 Piece General Maintenance Hole Cutter Set

I’ve never tried one but I see they are available individually also on eBay and reasonably priced.

 

[WranglerX]

When going bigger, I have a "bridge reamer"....Its easier on wrists and if use carefully will drill hundreds of holes ... Yes expensive but I can mark reamer to what hole size I need and just push it through to the mark.... Less tendency to bind up and break wrist if using portable drill motor...

Similar to this but mine is 15/16 (large end) for 7/8 clearance holes... Sort of wish I has gotten 1-1/16 though...

https://www.mscdirect.com/product/details/02341667

Shop around prices vary a lot...

Dale

 

[Gordon Gould]

Somebody above mentioned Champion hole cutters. You should give that a careful look. They are not just "hole saws". I use them too. They are excellent for what you seem to want to do. Accurately sized round holes with your drill press or hand held if need be.

CT7 5 Piece General Maintenance Hole Cutter Set

I also use hole saws in the drill press. Often much easier than drill bits. Mine have a 1/4 pilot bit in the center so I predrill a 1/4 hole location hole. The hole cutters will cut good until the kerf gets loaded with chips then it will feel like it has suddenly gone dull. Just stop and blow out the chips with the air hose or use a pick to clean them out then go again. A lot of complaints about hole saws are because people don't realize that you have to do this.



Milwaukee and Champion both make these.

gg

 

[NoTrespassing]

OK, I could buy a set of those M7 Drill Hog bits.

Does anyone have a recommendation for a good drill RPM speed chart for drill bit sizes and metal types? I did some Googling but there is a lot of other info that seems more prevalent (surface feet per min and feed speeds) which doesn't help my little brain with RPM. I do have a drill press that can go pretty slow (at least as low as 300 RPM) but need to know what I'm targeting.

Thanks,
Rob

Speeds and Feeds Calculator - Good Calculators