Is my drill press too fast for steel?

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Rancho5

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Feb 10, 2015
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After searching and researching, I'm concerned that my Harbor Freight drill press (760-3070 rpm) might run too fast for knife making. In your real world experience are the rpm's low enough to be an all around knife making drill press? I'll be starting with 1084 but eventually will use all kinds of steel.

Or maybe with cobalt bits I'd be fine? What do budget conscious knife makers do?

Thanks guys.
 
Rancho5 said:
After searching and researching, I'm concerned that my Harbor Freight drill press (760-3070 rpm) might run too fast for knife making. In your real world experience are the rpm's low enough to be an all around knife making drill press? I'll be starting with 1084 but eventually will use all kinds of steel.

Or maybe with cobalt bits I'd be fine? What do budget conscious knife makers do?

Thanks guys.
Click to expand...



That's plenty slow enough for the size drills that DP can handle, and that you're likely to be using for knifemaking.


The blanket statement of "run as slow as possible" is a good guideline for inexperienced machine operators, since too slow is better than too fast in most cases, but often times that's much much slower than optimal for cutter life.


In the case of your drill, you'll probably be fine just running it at 760 rpm for most sizes. Especially anything bigger than 1/8", but regardless, you should be fine. You shouldn't be running drills bigger than 1/2" in that machine though, and that'll be pushing it.


Regardless, buy premium quality drills for metal, from an appropriate supplier (not Lowes, Home Depot, or similar), and everything should be good.
 
Last edited:
^ yup

I run 1/4" drills at 900 RPM in things like annealed D2, 3V etc. The key is to feed hard enough that you're cutting and not rubbing. This is a problem at higher speeds and can lead to chatter, work hardening and poor cutter life. You have to feed hard enough to cut a chip, regardless of the RPM. This can be difficult to an inexperienced operator when the web exits the back side of the work piece and the drill suddenly overfeeds. Higher RPM makes problems happen faster.

I recommend coolant when running fast, and a couple pecks to prevent overheating the tip of the drill.

edit:
D2 at 660 RPM, dry:

[video=youtube_share;vAy11Fv4N7s]http://youtu.be/vAy11Fv4N7s[/video]
 
I'm glad it'll work. Thanks for the advise. Instead of Home Depot or Lowes, where shall I go, and are there certain sizes I'm sure to use more than others, rather than just buying a set and not using some? Also, cobalt, or something else?
 
ENCO Made in Usa cobalt. Buy these by the dozen in the sizes up to 1/8" or #30 for 1/8" pin holes.
 
Rancho5 said:
I'm glad it'll work. Thanks for the advise. Instead of Home Depot or Lowes, where shall I go, and are there certain sizes I'm sure to use more than others, rather than just buying a set and not using some? Also, cobalt, or something else?
Click to expand...

Good question

You have to drill a little oversized

for example a 1/4" pin will not fit in a .250" hole

check the wire gauge drill sizes and drill .002" over or so- check the chart and see what's close
 
I have that same press running at 760. Im drilling anything between 1/8 and 3/8" perfectly fine. Bits are still in good shape even after about 5 complete knives. I wouldn't go any bigger than 3/8" though. I had some trouble drilling 1/2".
 
The only time I go below 600 RPM is for countersinking (hole chamfering). I like to run a single-flute countersink at 300 RPM, which is the slowest I can go. I like single flute because I can sharpen it easily.
 
Just snagged a Ryobi DP-101 for $50 on Craigs. It got 570-3050 rpm. My HF is going back. The Ryobi seems a little more heavy duty. Plus I prefer to buy used higher quality than new less expensive.
 
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