Drilling 1/4" and thicker metal with a hand drill

[NCMau]

While a magnetic base drill may be the holy grail, Hougen makes several annual cutters that can be used in a hand drill or drill press, that will make life easier than using twist drills (which have a tendency to grab, when using larger sizes). Not to mention that the holes are actually round.

Well Bob, after reading your enthusiastic annular cutter post, I just had to try them myself. So I ordered a modestly priced set from ebay and I was amazed on how efficient they are compared to a twist bits. For my occasional use, these cutters totally eliminated my desire for a mag drill. To use the cutter on the drill press without removing the chuck, I cut the head off of a 1/2-20 bolt to use with a 1/2 drill female to 3/4 Weldon adapter. I could not locate online a stud for that purpose. That seems to be working okay, at least for cutters up to one inch anyway.
I do, however, have one question. Doing some reading online, I read nowhere about drilling a pilot hole before using the annular cutter. I drilled some 9/16 and 1/2 holes with a hand drill but if I did not have the center pin in the 3/16 pilot hole, the cutter would do some dancing and not be able to drill in the exact spot that supposed be.
I have to have a pilot hole whether I use the drill press or a hand drill. Is this the norm or did I miss something here? True, you can use a guide block as you pointed out, but that seems to complicate things, not just for the setup, but also for the exact location of the hole....... I am all ears.

 

[downsizingnow48]

I've used these Champion cutters for years. They are annular cutters with a pilot drill. In various hole sizes and material depths. They work great in either hand held or drill press. They are carbide tipped, I have never had one get dull yet.

CT7 - Carbide Tipped Hole Cutters

 

[BukitCase]

Not Bob, but maybe I can help - on an actual mag drill (mine, anyway) the center pilot pin serves two purposes - one is to be able to center punch where you want your hole and line the drill up so that pin "clicks into" the punch mark - the other is to automatically eject the "slug" when you raise the mag drill's quill back to the top (this defeats the normally spring-loaded pilot, whose THIRD function is to block coolant flow (sorta) til you actually start drilling...

If I'm understanding your setup correctly, you have the stock MT adapter and chuck in a drill press, then a headless 1/2"-20 bolt in that chuck, then a 1/2-20-to-3/4" weldon adapter (like this)
Steel Dragon Tools 1/2" Female Thread to Weldon Shank Adapter - - Amazon.com

then your annular cutter?

IF so, all those extra items (possibly including your drill press bearings, depending) are introducing too NON-rigid a mount NOT to get wander from the annular cutter - It may not have happened YET, but there's a good chance you may find out why annular cutters don't like a lack of rigidity in a drill - they tend to break under those conditions.

Of course, the best (not cheapest) way is to use them in the tool they were designed for; but unless/until you want to/can DO that, I have one suggestion that may help, if you aren't already DOING it -

MINIMIZE the "floppiness" in your setup as much as possible by making sure all your connections between chuck and adapter are as tight and true as you can, and always raise your DP's table up as far as possible (like having the cutter's teeth within maybe 1/4" of the piece to be drilled, with the quill at the TOP of its travel.)

Also, depending on how old your DP is it might be time to replace the quill bearings - I know my DP is past due for that (bought new in 1983)

Another option is to get some of the shallower "sheet metal" type annular cutters, they don't do more than about 1/2" deep but can even be used in a HAND drill - I have this kit

Blair 119 Rotobroach Cutter Kit Hole Saw Kit - Hole Saw Sets - Amazon.com

They offer several "kits"
Amazon.com: blair rotobroach: Tools & Home Improvement

As do Hougen and others.

I used them when beefing up the deck on my ZTR; plasma cut a bottom plate from 1/4" steel, drilled out the wimpy 1/4" mounting holes to 5/16", clamped the new plate in place, used a 5/16" transfer punch to get a centered punch mark in each hole, then drilled for bigger bolts with the new plate still clamped. No pain, big gain :thumbsup:

Keep in mind though, this type are mostly 1/4 to 1/2" depth of cut - that's a LOT of why they can be used in hand drills; too short for much "side loading"... Steve

(Now I KNOW my typing's gettin' slow - Pat "snuck in there" while I wuz writin' a BOOK :laughing: )

 

[downsizingnow48]

These Champion CT9 annular cutters with pilot bit are made in sizes up to 2" cutting depth.

 

[downsizingnow48]

I use the Blair cutters that Steve mentioned a lot. For hole sizes 5/16 through 3/4. The smaller sizes are good for 1/4" material which is the OP's question. The larger sizes are good for 1/2 material. Not very expensive, and they are very effective solutions for the needs of many home fabricators.

I seldom use a twist drill these days if I have a Blair or Champion cutter in the size needed. As others have mentioned, they require less effort and give you a rounder hole.

 

[dragoneggs]

Pat, I just looked at those Champion cutters on Amazon, thinking I would put a set on my wish list. Whoa! They must be good, they are not cheap!!! Dang it.

 

[2ndhalf]

When I was in maintenance, many years ago, our drill presses all had oil feeds that auto oiled the drill bits. Oiling a drill bit is to cut down on friction and cool the bit as it creates friction. Not enough oil will allow the bit to get too hot take the tempering out of the bit in a hurry and rendor your bit dull and useless until sharpened and if you take the tempering out of the bit your bits will not last long when sharpened.

Sharp Bits and lots of Oil.

 

[downsizingnow48]

Yep true. I bought the Blair set (now about 70 bucks) which covers about 85% of my hole cutting needs, plus some Champion bits on an as-needed basis. This is a lot more expensive than equiv HF twist drills, but for the sizes, much less expensive than industrial standard twist drills eg McMaster Carr. Truth in advertising, I bought a set of HF Silver and Deming drill bits which work just fine and also handle a lot of hole drilling needs.

 

[MossRoad]

Re: Drilling 1/4" and thicker metal with a hand drill

Bruce:

The Craftsman base already has a hole through the base that will allow my 5/8" bit to pass through. I thought for 10 bucks I'd find some alternate uses for them in the future.

Before I bought my mag drills I turned the headstock on this cheapo drill press 180 degrees and clamped it like you were suggesting.

View attachment 531240

I've had one of those on my workbench for well over 30 years. It's very handy. I mounted it in the table near the miter saw. So I can set a gauge block in the table and, say, cut a bunch of deck rail balusters, and just slide them over and drill pilot holes at the right height with another stop block. Only problem is if you mount a hand drill in it, you need one hand to hold the drill on and one hand to pull the lever to lower the drill, and a third hand to hold the work. So you can rig up a tie wrap to hold the drill trigger on, and a foot pedal or switch to turn the drill off and on......

Or you can buy a cheap harbor freight drill press for $49 on sale.

 

[dragoneggs]

Yep true. I bought the Blair set (now about 70 bucks) which covers about 85% of my hole cutting needs, plus some Champion bits on an as-needed basis. This is a lot more expensive than equiv HF twist drills, but for the sizes, much less expensive than industrial standard twist drills eg McMaster Carr. Truth in advertising, I bought a set of HF Silver and Deming drill bits which work just fine and also handle a lot of hole drilling needs.

I can see buying Champion for the particular diameter as needed and that is probably... or more should I say, definitely the way to do it. Have to keep them in mind for next time. Just can't justify buying the kit as much as I would smile when opening the tool drawer.