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Which Drills to buy
- Thread starter Dgrose
- Start date
I also have the HF cobalt set of 100+ drills, have had since long before I got the lathe. Have replaced a few of the smallest, #50+, over time, but the others are fine, sharp as if new. I consume the 61-80 really little guys and buy them in tubes of 10 or 12, but they're too small for the lathe anyway.
Tim
Tim
- Joined
- Apr 23, 2018
- Messages
- 6,561
I think it's better to start with a set, that way you have the darn drill you need on hand by default. Then replace what you break. I've done pretty good with the Shars HSS sets, they're good quality at a step down in price from the good stuff.
Harold Hall and Tubal Cain might straighten out some of the confusion about drill point angles. Hall's tool sharpening book and Cain's drill, tap, and die book from the Workshop Practice series are both in our site's download section. The point angle on a twist drill is akin to the rake of a lathe bit, which is a specification you select based on the material you are cutting. 135 degree bits do punch through hard metal because they are pointy, but once the point is sunk in the work the rake angle will matter more. See chart.
Split points have many advantages in that they are center-cutting and really control wander. As much as I love my little cutter grinder, split points are a whiz-bang cinch to sharpen with a Darex Drill Doctor. I've had mine for 25 years, and that little guy just keeps on ticking like a Timex watch. You can grind a split point on any ordinary drill, so no reason to pay extra for them when they are new.
Harold Hall and Tubal Cain might straighten out some of the confusion about drill point angles. Hall's tool sharpening book and Cain's drill, tap, and die book from the Workshop Practice series are both in our site's download section. The point angle on a twist drill is akin to the rake of a lathe bit, which is a specification you select based on the material you are cutting. 135 degree bits do punch through hard metal because they are pointy, but once the point is sunk in the work the rake angle will matter more. See chart.
Split points have many advantages in that they are center-cutting and really control wander. As much as I love my little cutter grinder, split points are a whiz-bang cinch to sharpen with a Darex Drill Doctor. I've had mine for 25 years, and that little guy just keeps on ticking like a Timex watch. You can grind a split point on any ordinary drill, so no reason to pay extra for them when they are new.
- Joined
- Feb 2, 2017
- Messages
- 1,234
I bought a complete set of US made numbered, fractional, and lettered cobalt split point screw machine bits from a retired machinist. They are nearly new--most do not look like they've ever been used. They were not cheap--I paid 50% of new from the catalog he had from about 10 years ago--I think $300 for all of them. The same sets would be about $1k new now. I have a bunch of other used HSS jobber-length drills I use most of the time, but if I'm doing something I particularly care about, the cobalt drill comes out and is a joy to use.
- Joined
- Dec 20, 2012
- Messages
- 9,422
Hey Evan, gotta' tell you this story. I spotted a brand new set of Titex cobalt drills and matching taps on ebay. It was a micro set for holes up to 10-32, complete with the tap handle to drive them; retail for this set was over $300.00, if I recall correctly. Opening bid was $5.00, with free shipping, and the auction ended at something like 3am, Hawaii time. I guess I was the only one awake at the time and I won that set. I felt sorry for the seller, poor guy. When I have to tap tiny holes in stainless, this set comes out.
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- Mar 26, 2018
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Ebay is rarely a place for great deals in my experience. You got a deal sir.
- Joined
- Dec 20, 2012
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- 9,422
Yeah, I did, but I still find a lot of deals on ebay. You just have to know what you want, how to find it, how to bid on it, how to walk away and how to be patient.
My last brand new 1/2" Albrecht chuck was $85.00 and this was about 2 years ago. There were two and the rest of the 19 bidders went for the second one. My brand new PTD 115 piece screw machine drill set came in at $100.00, shipped. I just "won" a brand new set of Borite cobalt micro boring bars last week - $50.00, and I was the only bidder.
I cannot even begin to list the deals I've gotten on ebay, even today. It does help that I know what I'm looking for, though.
- Joined
- Nov 23, 2014
- Messages
- 2,609
I have a set of the cobalt HF drills for under $100 and like them. I've found the $20 sets of 29 fractionals to be of questionable quality. Most of mine are US made HSS from Cleveland. I've had very good luck with Norseman and Viking.
One thing I'd recommend is watching some videos on how to sharpen a drill bit. You can drill better with a $1 sharp import drill bit than a $100 dull domestic. They are going to dull, so might as well learn to sharpen them. I've had very good luck with my Drill Doctor 750 drill sharpener. Really tough, at least for me, to sharpen anything under 1/8" by eye anymore.
You mentioned screw drills. Jobber length are the most common but the screw machine (or stubby) drills can be handy on a mill. You should probably center or spot drill holes in steel for bits under 1/4" to keep them on center. The screw machine drill bits are around 1/2 the length and relatively more rigid. You can usually get away without spot drilling first. Another plus with the shorter length is head room on a mill. If you mount a 1/2" end mill directly in an R-8 collet, it hangs out of the spindle by just over the length of the exposed end mill. A drill chuck hangs down easily lower than a 1/2" end mill, then you have the length of the drill bit on top of that. Stubbies buy you a few inches of head room if that's important.
Bruce
One thing I'd recommend is watching some videos on how to sharpen a drill bit. You can drill better with a $1 sharp import drill bit than a $100 dull domestic. They are going to dull, so might as well learn to sharpen them. I've had very good luck with my Drill Doctor 750 drill sharpener. Really tough, at least for me, to sharpen anything under 1/8" by eye anymore.
You mentioned screw drills. Jobber length are the most common but the screw machine (or stubby) drills can be handy on a mill. You should probably center or spot drill holes in steel for bits under 1/4" to keep them on center. The screw machine drill bits are around 1/2 the length and relatively more rigid. You can usually get away without spot drilling first. Another plus with the shorter length is head room on a mill. If you mount a 1/2" end mill directly in an R-8 collet, it hangs out of the spindle by just over the length of the exposed end mill. A drill chuck hangs down easily lower than a 1/2" end mill, then you have the length of the drill bit on top of that. Stubbies buy you a few inches of head room if that's important.
Bruce
- Joined
- Nov 27, 2012
- Messages
- 7,863
Not my experience. 90% of my tools (not just machining related) that were great deals came from ebay over the past 10-15 yrs. All the unbelieveable steal deals I have got were from ebay. Deals were much better 5+ yrs ago though. Now a days they're harder to find & have to sort out all the China listings but deals are still there. Like Mike said, need to know how to find them as well as be patient & know how to bid on them.
My Eagle Rock K1-44 that costs around $400 I got for $85 shipped, was practically brand new. I got a 29 pc fractional set of Alvord-Polk reamers that costs around $700 for $70 shipped. Only 1 of the reamers looked like it was ever used. That one was a big surprise, I honestly thought I was buying an Chinese import set. Most of my measuring tools are from ebay as well as all my titanium stock. Plenty more but those 2 I remember the most. I just bought 2 brand new Dorian BXA holders last night for $40 ea.