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Getting ready to drill lots of holes - speeds/feeds check
- Thread starter stioc
- Start date
FYI - Amazon has a pretty good deal on YG-1 parabolic stub length drills. I'm a big fan of parabolic flutes in aluminum as I can plow down with no pecks fairly deep. The flutes clear chips like mad, and you can up the feed rate. I'm running flood, but a squirt of kerosene or WD40 also works.
A quality, straight stub length drill means no spot-drill needed. One less operation & tool change.
If you find yourself drilling lots of 1/4-20 holes, especially in aluminum, you might consider switching to form taps. No chips, no backing it out every turn or two. Nicer threads. Just buy a 15/64 or "C" drill and have at it.
I've also switched from buying/using drill indexes to individual drills. There are about 5-10 drill sizes I use constantly and I've found that buying a few nice drills in just those sizes means they cut better and I'm not up the creek if I wreck one. I sitll have an index for those odd-ball sizes, but mostly use the 'good'' drills in the most-frequently needed sizes.
Just a suggestion, but if you buy 5-packs of individual drills they can get pretty inexpensive. As I mentioned, I'm big fan of the YG-1 stuff. They aren't top of the line, but they're way, way cheaper than OSG, Guhring, or Nachi and they are light-years ahead of 'cheap' drills. Widia is another lower-cost but quite good quality brand.
A quality, straight stub length drill means no spot-drill needed. One less operation & tool change.
If you find yourself drilling lots of 1/4-20 holes, especially in aluminum, you might consider switching to form taps. No chips, no backing it out every turn or two. Nicer threads. Just buy a 15/64 or "C" drill and have at it.
I've also switched from buying/using drill indexes to individual drills. There are about 5-10 drill sizes I use constantly and I've found that buying a few nice drills in just those sizes means they cut better and I'm not up the creek if I wreck one. I sitll have an index for those odd-ball sizes, but mostly use the 'good'' drills in the most-frequently needed sizes.
Just a suggestion, but if you buy 5-packs of individual drills they can get pretty inexpensive. As I mentioned, I'm big fan of the YG-1 stuff. They aren't top of the line, but they're way, way cheaper than OSG, Guhring, or Nachi and they are light-years ahead of 'cheap' drills. Widia is another lower-cost but quite good quality brand.
- Joined
- Feb 27, 2014
- Messages
- 2,274
I also switch to sub length and also only buy the sizes I need. By that I mean that I keep at least one of all standard sizes but have 4 or 5 of the sizes that I use most often. I resharpen the larger bits and just replace the smaller ones when needed.
Wow, thanks for the tip! I had no idea there was such a thing as a parabolic drill, sounds fancy and sounds like it works well too. So parabolic drills clear chips better hence no need for pecking?
Is this the one you're talking about? https://www.amazon.com/YG-1-Machine-Straight-Parabolic-Diameter/dp/B014J2E76W/
BTW the Dewalt drill I used is also a 130 (or 135?) deg drill so when I drilled from the other side after flipping the piece over I didn't spot drill (I actually forgot lol) but supposedly the 130/135 deg drills don't walk like the 118 deg ones do - worked for me!
Yes, that's the bunny. Pokes holes like mad. I just drilled about 4" deep in some brass with a 31/64" YG-1 parabolic in one shot on my manual lathe. No pre-drill - just a spot to get it started concentric. I was ready to pull it out to clear things but the chips kept flowing out instead of packing in the flutes.
[By the way, that 15/64 is for a 1/4-28 form tap, not 1/4-20. Be sure to check the tap mfgr's recommended pre-tap hole size and don't take my word for it]
As far as speeds go - if you buy name-brand (not Dewalt!) cutting tools the manufacturer usually has feeds & speed recommendations, as well as tech data about pecking depths. In the case of the 15/64" YG-1 drill, they recommend 3200RPM and .003IPR in aluminum. That works out to 9.6IPM feed.
And because of the parabolic flute, you should be able to do that .750 deep hole in one shot - no pecks. I'd have the squirt gun at the ready, however, and keep it lubed and blow the chips off when it retracts.
Using your settings, Fusion reports 10:45 to drill all the holes (not including spotting). Using the YG-1 settings, it's 7:23.
Depends on how fast you can change belts/gears to the higher ratio, I guess.
Finally, the tip angle of 118 vs 130 isn't what lets you get away without spotting the hole. It's the short length drill and a split point that does it. I'm pretty sure that the 130 tips are designed for harder material. I happen to favor them for everything (except plastic) since my drills are used in all materials.
[By the way, that 15/64 is for a 1/4-28 form tap, not 1/4-20. Be sure to check the tap mfgr's recommended pre-tap hole size and don't take my word for it]
As far as speeds go - if you buy name-brand (not Dewalt!) cutting tools the manufacturer usually has feeds & speed recommendations, as well as tech data about pecking depths. In the case of the 15/64" YG-1 drill, they recommend 3200RPM and .003IPR in aluminum. That works out to 9.6IPM feed.
And because of the parabolic flute, you should be able to do that .750 deep hole in one shot - no pecks. I'd have the squirt gun at the ready, however, and keep it lubed and blow the chips off when it retracts.
Using your settings, Fusion reports 10:45 to drill all the holes (not including spotting). Using the YG-1 settings, it's 7:23.
Depends on how fast you can change belts/gears to the higher ratio, I guess.
Finally, the tip angle of 118 vs 130 isn't what lets you get away without spotting the hole. It's the short length drill and a split point that does it. I'm pretty sure that the 130 tips are designed for harder material. I happen to favor them for everything (except plastic) since my drills are used in all materials.