Those drill sets are so cheap, it is not worth my time to inventory drills, I just buy more sets.
- posted
15 years ago
Those drill sets are so cheap, it is not worth my time to inventory drills, I just buy more sets.
" snipped-for-privacy@gmail.com" fired this volley in news:7f8f7124-995a-4669-bf89-0877d8669306 @b38g2000prf.googlegroups.com:
I find the opposite. Those Chinalloy bits are so poorly made of such a lousy alloy, and so badly ground, that they last about 1/10 the hole depth of good American bits. They're also often not precisely of the correct diameters.
I'd rather spend my money on bits I can periodically re-touch and have them last years.
LLoyd
I had a very negative experience with the cheapest drills. They might be mild steel that is TIN coated. The fail in the hole and then the only thing that can get drilling to continue, is carbide. I use cheap drills to drill through aluminum or drywall or some other stuff like this.
A while back, I bought one of the big drill sets on sale from Enco or MSC. I got one with the combined letter, number & fractional drills. I decided to get the middle-ground "no name" HSS american made set, as opposed to the cheap import set, or the very expensive name-brand US set.
They are a mixed bag, but have served me very well. Some of the drills have no size marking on them, some are nicely etched, and some are stamped so deep I have to stone them to get them to run true. The one rude surpise I got was with a number drill about 0.1" in diameter. I chucked it up after checking the shank for severe stamping ridges, and went to work. It just wouldn't cut, even in aluminum, and after a few attempts, I took it out and examined the business end. The point was ground "backwards", in that the heel was higher than the cutting edge (negative lip angle)! Since then, I check the point of every bit before I use it. So far that's the only one I've found. The steel seems to be generally high quality, and there rest are all nice & sharp.
Doug White
I think I'll stick to PTD brand. Never had luck with cheap drill bits.
Wes
I have had bad cheap drill experiences in the past, but the 115 drill set I got for $35 from CDCO was very good. I think a good test is to drill mild steel with a 1/8" drill, as I have envelopes full of 1/8" drill, so I can sacrifice it.
Drill fast and hard with coolant. The drill should drill fast and stay sharp. The CDCO set passes this test.
Correct me if I am wrong.
I found the same thing once. Wouldn't drill at all. I kept checking to make sure I was turning the right way, and then once I check the drill bit, I saw the problem. Reground it to a proper angle and it worked fine after.
JW
The $35 CDCO drills are drilling as fast and staying sharp on a par with the Precision Twist Drill Company Crystal Lake IL and Triumph twist drill also of Crystal Lake IL.
I don't know if the quality I a getting is a temporary fluke or if the Chinese have figured out how to make drills.
" snipped-for-privacy@gmail.com" fired this volley in news: snipped-for-privacy@v39g2000pro.googlegroups.com:
IF they're made from M2AL alloy, they're probably as good as the US bits, assuming they're also sized and ground correctly.
Usually, they'll specify that if it's the case. (they're pretty proud of that alloy, when they decide to spend the money on it and the heat- treatment it requires).
LLoyd
I bought some BS #9 collets from them last year, much chaper than anyone else, and appeared to be of good quality. Fast, cheap shipping.
China quality is hit or miss. Glad you got a hit.
Wes
Someone asked me if the drills are ground or forged. They are ground like the expensive US made drills.
The tool holders for the lathe are so cheap, I can buy more and have more tools ready to put on the lathe in a moment.
Now the AXA series tool holders seem to be pretty good. I have quite a few. Lathe came with a real Aloris tool post and CDCO's fit it fine. I did get one that required a bit more rotation of the locking lever but still usable.
Wes
-- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller
few. =A0Lathe came
that required a bit
The tool holders are what got me started there. My brother's shop and mine both soak up lathe tool holders at the CDCO price.
Any idea how hard they are? I occasionally need to modify them, and the real McCoy are at least case hardened. The most common thing is that I need to knock ~50 mils off the bottom to use 1/2" tooling because my compound is just a bit high. I've found the Phase II holders are easier to machine, but the CDCO's are even cheaper.
Doug White
I'll try to remember to take one to work to check Rc. Might take me a day or so to get to it but I'll post back to this thread.
Feel free to jog my memory if I forget.
Wes
One free jog...
Thanks!
Doug White
I went out to garage and grabbed one. It is in my coat pocket. I'll take it to work tomorrow.
Wes
Almost forgot. I took a few measurements across the bottom of a CDCO AXA holder.
44.3, 40.7, 48.3, 45.4Then thinking about your comment on case, I checked on both sides of the ground surface.
46.2, 45.8 on the Rc scale. Instrument is in calibration.Average of all readings is 45.1 Rc.
Wes
so to get to
Almost forgot. I took a few measurements across the bottom of a CDCO AXA holder.
44.3, 40.7, 48.3, 45.4Then thinking about your comment on case, I checked on both sides of the ground surface.
46.2, 45.8 on the Rc scale. Instrument is in calibration.Average of all readings is 45.1 Rc.
Wes
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