RotoMetals2Lee PrecisionMidSouth Shooters SupplyADvertise here
Graf & SonsTitan ReloadingStainLess Steel MediaInline Fabrication

Page 1 of 2 12 LastLast
Results 1 to 20 of 34

Thread: Need lathe advise.

  1. #1
    Boolit Master



    Join Date
    Oct 2008
    Location
    LEESBURG VA
    Posts
    682

    Need lathe advise.

    The lathe is running and I started on the list. I got halfway through the first drill hole pulverized the drill bit. All I know it was supposed to be titanium coated.
    Thanks,
    Bill

  2. #2
    What material, hole diameter, and spindle speed? Was it a new sharp bit? Did you use a center drill to start the hole?

  3. #3
    Boolit Man
    Join Date
    Sep 2011
    Location
    Australia Philippines (Good)
    Posts
    143
    Im going bet the drill bit was Chinese....

  4. #4
    Banned




    Join Date
    Mar 2014
    Location
    409 area code -- Texas, ya'll
    Posts
    3,724
    Quote Originally Posted by M.A.D View Post
    Im going bet the drill bit was Chinese....
    Even with the HF drill bits (which I assume are Chinese), I only break the really small ones. Once I get up to 1/8" or maybe 1/4", the chance of breaking one is a LOT less.

    But, yeah, if you are on a lathe, start with a center hole. Even the HF center cutters are useful.

  5. #5
    Super Moderator




    Buckshot's Avatar
    Join Date
    Mar 2005
    Location
    So. California
    Posts
    11,545
    ..............Not enough info. A Titanium coating isn't magic, and depending upon what you're doing probably isn't really necessary. Remember too, the first time you sharpen it the coating is gone on the business end.



    Personally for most of my drilling in the lathe or milling machine I really like parabolic flute type bits. And yes this one is TiN coated but I don't specifically buy them so. Their benefit is primarily chip clearance/flow. Don't know what you mean by 'Pulverize' either. There are quite a number of possible reasons. Everything from poor quality bits, simple lack of coolant/lube, to chip packing, or a material issue.

    ..................Buckshot
    Father Grand Caster watches over you my brother. Go now and pour yourself a hot one. May the Sacred Silver Stream be with you always

    Proud former Shooters.Com Cast Bullet alumnus and plank owner.

    "The Republic can survive a Barack Obama, who is, after all, merely a fool. It is less likely to survive a multitude of fools such as those who made him their president."

    Shrink the State End the Fed Balance the budget Make a profit Leave an inheritance

  6. #6
    Boolit Master

    Join Date
    Jun 2009
    Location
    North central Ohio
    Posts
    714
    Usually you have to run small drill bits pretty fast, clearing chips often and use a good lube. I have found, generally speaking cheaper drills are usually pretty dull and ground improperly right out of the package. All Chinese drills need sharpened before using and then their kinda "ok" for not too demanding tasks. It is dang near impossible to sharpen real small bits in the home shop environment so I have an assortment of higher quality drill bits and center drills that are used frequently and save the marginal/Chinese for projects that require me to enlarge existing holes.


    We accumulate our opinions at an age when our understanding is at its weakest. Georg C. Lichtenberg

    At what point, then, is the approach of danger to be expected? I answer, If it ever reach us it must spring up amongst us; it cannot come from abroad. If destruction be our lot we must ourselves be its author and finisher. As a nation of freemen we must live through all time, or die by suicide. A. Lincoln

  7. #7
    Titanium coatings mostly just reduce wear on a drill which is working properly in a suitable material. So they benefit factory production more than the amateur with one job to do in less than ideal circumstances.

    Deep-hole drills are about the most effective of all, and they have a point off-centre, so that the bottom of the hole is slightly W-shaped. A good drill sharpening jig is valuable, but an incorrectly sharpened drill can work quite well, if you already have a hole and a drill chuck or collet which are precisely located on the axis of rotation. A really good stub or centre drill to start the hole, followed by a cheap long drill, can do a good job.

  8. #8
    Boolit Master rondog's Avatar
    Join Date
    Mar 2009
    Location
    Denver, CO
    Posts
    1,499
    Speed? Material? Drill size? Coolant? Cutting oil? Power feed or manual?

    Lots of factors here.

  9. #9
    Boolit Master



    Join Date
    Oct 2008
    Location
    LEESBURG VA
    Posts
    682
    Holy cow:
    Grade 5 bolt
    1/4"
    600RPM +/-
    Center drill used
    New or close to new
    Though parabolic were for aluminum
    Chinese ?
    Manual feed

    Drilled as far as the quill would allow, kept oiled, cleaned the chips regularly. It broke half way through the second pass. First time I broke anything over 1/8".

    Was a little apprehensive about Harbor Freight.

    Thanks,
    Bill
    Last edited by just bill; 01-27-2017 at 08:23 AM. Reason: Computer word generators, spelling and added info.

  10. #10
    Boolit Master Moleman-'s Avatar
    Join Date
    Jul 2016
    Location
    SW Michigan next to a winter wheat field
    Posts
    367
    Usually what I run into drilling a deep pocket on the lathe is chip packing. The deeper you go the more frequently the chips need cleared which can be tedious if you have to unbolt the tailstock each time as you're past the travel of the quill. Lots of cutting fluid and a sharp bit will help keep the bit temp down will help it from heating up to the point where the OD of the bit expands and wants to lock up in the bore. Chinese bits are all over the board on quality. Some soft, some brittle. I've even received a set as a gift a few years back where they weren't sharpened. Almost like the sharpening jig was 90 degrees off and the cutting edges were ground off.

  11. #11
    Boolit Master

    Join Date
    Feb 2008
    Location
    Bozoland Mt.
    Posts
    1,321
    Even the best of bits will dull if you let them rub. The cutting action depends on curling away material, if the bit is touching the material and not cutting it is rubbing.
    6000 rpm is pretty fast for a .250 bit.
    I have feeds and speed program, I punched in steel, medium carbon alloy (1045)
    .250 highspeed steel bit
    1.5 " hole depth
    it returned
    722 rpm 1.45 inch per minute feed, with a peck depth of .250
    My program is limited to 1 1/2 horsepower machine.
    At 2'' depth of cut I was warned to use a parabolic bit.
    A parabolic bit refers to the shape of the flute, they are more expensive to manufacture. But give greater volume to hold and flow chips with good bit strength.
    Last edited by clodhopper; 01-27-2017 at 11:30 AM.
    To lazy to chase arrows.
    Clodhopper

  12. #12
    Boolit Master



    Join Date
    Oct 2008
    Location
    LEESBURG VA
    Posts
    682
    I think I've narrowed it it speed and chip removal. I'm trying again later with a new drill.
    Bill

  13. #13
    Boolit Master
    Join Date
    Nov 2010
    Location
    Nevada
    Posts
    204
    Quote Originally Posted by Jeff Michel View Post
    Usually you have to run small drill bits pretty fast, clearing chips



    often and use a good lube. I have found, generally speaking cheaper drills are usually pretty dull and ground improperly right out of the package. All Chinese drills need sharpened before using and then their kinda "ok" for not too demanding tasks. It is dang near impossible to sharpen real small bits in the home shop environment so I have an assortment of higher quality drill bits and center drills that are used frequently and save the marginal/Chinese for projects that require me to enlarge existing holes.
    Also if you are using steel its much better to go with a 135 degree point than your 118 degree and use cobalt drills

  14. #14
    Boolit Master lead chucker's Avatar
    Join Date
    Jan 2010
    Location
    Alaska
    Posts
    641
    Cobalt drill bits work good. I have a set and really like them. They don't give them away that's for sure. Center drilling I have found is a must.
    Dont pee down my back and tell me its raining.

  15. #15
    Boolit Master
    smokeywolf's Avatar
    Join Date
    Jan 2011
    Location
    Too far west of where I should be.
    Posts
    3,252
    HS-Cobalt drills, 135 degree split point.
    TiN or TiAlN coatings, usually a little pricey for the home shop machinist are helpful in resisting abrasion, heat buildup and chip welding.

    If your going to be doing more than occasional deep hole drilling you might want to consider getting an air compressor and a coolant mister. Not as good as a coolant-thru drill, but will reduce greatly the peck-drilling.

    I avoid VA, Hanson, Greenfield and all China made cutters. Greenfield used to be real good, but back in the 1990s they started buying off-shore HS and HS-Cobalt and just doing the grinding here. They don't hold an edge for karp.

    For drills I stick with Union, Chicago Latrobe, Cleveland, Precision Twist Drill (PTD), Guhring and one or two others.
    A well regulated militia, being necessary to the security of a free State, the right of the People to keep and bear arms *shall not be infringed*.

    "The greatest danger to American freedom is a government that ignores the Constitution."
    - Thomas Jefferson

    "While the people have property, arms in their hands, and only a spark of noble spirit, the most corrupt Congress must be mad to form any project of tyranny."
    - Rev. Nicholas Collin, Fayetteville Gazette (N.C.), October 12, 1789

  16. #16
    Boolit Master



    M-Tecs's Avatar
    Join Date
    Apr 2008
    Location
    Minnesota
    Posts
    4,646
    Quote Originally Posted by smokeywolf View Post
    I avoid VA, Hanson, Greenfield and all China made cutters. Greenfield used to be real good, but back in the 1990s they started buying off-shore HS and HS-Cobalt and just doing the grinding here. They don't hold an edge for karp.

    For drills I stick with Union, Chicago Latrobe, Cleveland, Precision Twist Drill (PTD), Guhring and one or two others.
    That has been my experience also. Some of the cheap stuff it real junk compared to a quality bit.

  17. #17
    Boolit Master

    Join Date
    Feb 2008
    Location
    Bozoland Mt.
    Posts
    1,321
    I bought the Harbor Freight 105 piece cobalt set on sale for 79 bucks or something. Most of the bits were pretty good, One so far was not sharp from the factory.
    I set it up in a cnc mill with proper speed, feed and lube, it immediately started screeching and smoking. Rechecked the feed, and speed, no go

    You get what you pay for, with the harbor freight set I got a nice index for storing bits, number bits from 1-60, letter bits A-Z, and 1/64-1/2 by 64ths. Of the 20 or so bits I have used in the set so far only one was bad, it was so bad that it showed up first try. The set was all I had at first, now it is a back up.

    Since then I have been building a stock of screw machine length bits.
    The shorter lengths bits suffer less from deflection. Mostly buying the sizes useful for an immediate project.

    I am fortunate to have supplier very close to home, I can take a mile detour from dog walking, go in the store, and buy at reasonable prices endmills, bits, coolant, carbide inserts and more.
    To lazy to chase arrows.
    Clodhopper

  18. #18
    Boolit Master

    Join Date
    Mar 2013
    Location
    Northwest Ohio
    Posts
    7,646
    A little tip to help out, Make sure all the old drill bit is out of the hole before trying again or come in from the other end. Center drill and drill with a good black sulfar oil clearing chips every .050 or so and making sure oil is getting up to the point. On small holes deep holes this can be tricky. Deep hole drills are hollow and oil is pump thru the drill under high pressures to the cutting edges this keeps things cool and clears chips much better. We would set the machines up to "peck" drill .050 or so ( depending on drill dia.) and clear break the chips. On manual machines about a 1/4 -1/2 turn on the tailstock for 1 revolution then clear chips works.

  19. #19
    Boolit Master

    Join Date
    Apr 2014
    Location
    Oregon. Hate the politics, but love the weather!
    Posts
    1,834
    Speeds and feeds, speeds and feeds. And sharpness, and oil, and material. All a learning process. Whatcha makin' wit de bolt? A die?

  20. #20
    Boolit Master Idz's Avatar
    Join Date
    May 2013
    Location
    New Mexico
    Posts
    501
    The most important thing I learned about the chinese lathes is to make sure everything is solidly locked down. Any loose parts in the chuck, tailstock, drill chuck, or feeds and you will break bits.

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check