Power feed drilling.
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Power feed drilling.
Want to mount a 3 jaw chuck on a 5-C shank. The fixture head I have laying around it toooo small .Rats! So make a adapter plate to fit the two pieces together. Had a chunk of 5" bar laying around [mystery metal acts like 4140 chip wise] sawed off a .800 aprox thick piece ,faced both sides . Fixture head has a 1" male stub so needed to drill/bore a hole in plate for a light press fit [will be bolted also] Drilled a 1/2" pilot hole then punched a 7/8" through. I was lazy so used the SB heavy 10 with the 4 jaw,should used the 12" gear head! Lowest speed back gear at a little over .002 rev feed was all it would before stalling. Miserable flat belts ! Drill was a 118* point which didn't help,opening up to 7/8 worked better. Hole surprisingly was only .001 over size ,not bad for some Indian taper shank bits I've had for 20-30 years.Finished the hole to 1" with a insert boring bar. I suppose I could have used a drill chuck in the taper bit tool holder and used 135* split point for pilot and 31/32 S&D drill to save on boring time. What fun is that!!! Anyway using power carriage feed beats cranking TS !
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Re: Power feed drilling.
Your pictures speak to how securely and accurate you were able to hold that drill. We can see the chip strings coming out equal. That's pretty impressive.
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Re: Power feed drilling.
SPRO: Ya ought to see the chips when I do the same on the 18" lathe with .012 or so feed per rev. pushing a 1.5 drill through mild steel with a 1/2 pilot hole. You stand back out of the way!
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Re: Power feed drilling.
If you've ever operated a (serious) radial drill press, you likely know that you can do that with larger drills and more than double the feed, no sweat!John Evans wrote:SPRO: Ya ought to see the chips when I do the same on the 18" lathe with .012 or so feed per rev. pushing a 1.5 drill through mild steel with a 1/2 pilot hole. You stand back out of the way!
H
Wise people talk because they have something to say. Fools talk because they have to say something.
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Re: Power feed drilling.
No room for a radial. A year ago a Giovanni Breada [sp] came up for sale on clist here for $1000,my tool dealer friend bought it. Nice, 6-8" column as I recall was in really good condition.Harold_V wrote:If you've ever operated a (serious) radial drill press, you likely know that you can do that with larger drills and more than double the feed, no sweat!John Evans wrote:SPRO: Ya ought to see the chips when I do the same on the 18" lathe with .012 or so feed per rev. pushing a 1.5 drill through mild steel with a 1/2 pilot hole. You stand back out of the way!
H
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Re: Power feed drilling.
My dad used the power feed to drill a large model cannon barrel.
The comparatively short tailstock travel would have made it a chore.
Funny thing was that he had turned the outside of the barrel maybe 25 years earlier on the South Bend 9A, but that lathe was too short to drill the barrel. The Clausing did it no problem.
Steve
The comparatively short tailstock travel would have made it a chore.
Funny thing was that he had turned the outside of the barrel maybe 25 years earlier on the South Bend 9A, but that lathe was too short to drill the barrel. The Clausing did it no problem.
Steve
Re: Power feed drilling.
I feel your pain.John Evans wrote: No room for a radial. A year ago a Giovanni Breada [sp] came up for sale on clist here for $1000,my tool dealer friend bought it. Nice, 6-8" column as I recall was in really good condition.
While it would be hard for me to justify owning one, there was a beauty that went in an auction up here about a couple years ago. Wish I could remember the details, but I do recall it would have been perfect for the smaller shop. I'd have loved to have added it to my collection, but then I'd love to add a centerless grinder, too. No end to my hopes and dreams, or so it seems.
H
Wise people talk because they have something to say. Fools talk because they have to say something.
- SteveHGraham
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Re: Power feed drilling.
I'm always afraid to push drills. The other day I needed to drill a 1/2" hole in 304. I was using scrap, and I had already used a rotary broach to put a hex hole in the end. I drilled into the hex with a 1/4" bit, and it started popping like it was hitting gravel.
I was going to give up and use a smaller drill, but it occurred to me that there might be a work-hardened area at the bottom of the hole, and that a bigger bit might work just as well, since it would be hitting softer metal. I didn't look at the size of the next bit I used, but it was up close to 1/2", and it ran right through the work. Didn't even have to peck. Went about 2.25" in.
I never know what the drills and the machines are capable of.
I was going to give up and use a smaller drill, but it occurred to me that there might be a work-hardened area at the bottom of the hole, and that a bigger bit might work just as well, since it would be hitting softer metal. I didn't look at the size of the next bit I used, but it was up close to 1/2", and it ran right through the work. Didn't even have to peck. Went about 2.25" in.
I never know what the drills and the machines are capable of.
Every hard-fried egg began life sunny-side up.
Re: Power feed drilling.
I made mention of the radial drill simply because of the ability of a twist drill to move metal. Given the proper setup and power, they can move it at a horrifying rate---much like watching a horizontal mill running a side cutter.
I'm not a fan of machining 304. Been there, done that, and have achieved success as required, but once you've machined either 416 or 303, you tend to learn to hate the stuff.
Interestingly, 303 and 304 are almost identical, chemically. The chief difference is the element chosen for free machining, either sulfur or selenium. What a difference they make!
H
I'm not a fan of machining 304. Been there, done that, and have achieved success as required, but once you've machined either 416 or 303, you tend to learn to hate the stuff.
Interestingly, 303 and 304 are almost identical, chemically. The chief difference is the element chosen for free machining, either sulfur or selenium. What a difference they make!
H
Wise people talk because they have something to say. Fools talk because they have to say something.
- SteveHGraham
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Re: Power feed drilling.
What speed do you think you would use to push 7/16" in 304? I am curious. I think I was under 300.
Every hard-fried egg began life sunny-side up.
Re: Power feed drilling.
Before we lose the original intent of my reply: I was commenting about the rigidity of many different sections of the lathe. The drill wasn't powered by a quilled spindle to a massive table. Nothing like that. It depended upon the tool holder for the drill ( which I think was an internally tapered adapter) to a secure tool holder to a solid ( when locked, tool holder), to a compound and cross slide. Then the whole carriage is powered and achieves the accuracy evident by the chips. THIS doesn't happen by accident.
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Re: Power feed drilling.
Using HHS bit I would start at about 200 RPM with lube. SS needs to have a chip coming off all the time,rub a bit and instant work hardening.SteveHGraham wrote:What speed do you think you would use to push 7/16" in 304? I am curious. I think I was under 300.
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