Graf & SonsRotoMetals2Lee PrecisionInline Fabrication
WidenersStainLess Steel MediaMidSouth Shooters SupplyTitan Reloading

Results 1 to 17 of 17

Thread: Anyone know a machine shop that can drill out a 7/8-14 and tap for 1-1/4-12 ?

  1. #1
    Boolit Master
    Join Date
    Feb 2007
    Location
    South West Ohio
    Posts
    1,457

    Anyone know a machine shop that can drill out a 7/8-14 and tap for 1-1/4-12 ?

    I have a Redding T-7 toolhead that I would like drilled out from its 7/8-14 and tapped to the larger 1-14"-12 size. I saw one that was done years ago and there was enough meat to do it.

    I know any machine shot could do it but if anyone knows one that already has the drills and taps for it, it would likely be much less expensive. I'd rather not but a very expensive drill and tap for one project....but I will if I have to.

    I'm a little confused on where to post this....
    The good thing about science is that it's true no matter if you believe it or not. (Neil DeGrasse Tyson)

    I was scolding my 5-year old for her and her friends making a giant mess in her room. She said they all did it. So I asked her: If all her friends jumped off a cliff, would she do it too? She said, "Oh no daddy! I would go to the bottom and try to catch them! They're my friends." Man, either I have a great kid or she has a stupid father.

  2. #2
    Boolit Master


    Join Date
    Sep 2007
    Location
    longview,tx
    Posts
    2,553
    You could most probably buy a used Rockchucker press for the cost of the machine work.
    It would be stronger.
    I am assuming you want to use this for 50BMG dies?

    Ebay has the taps for about $30+ shipping
    The 1-11/64” drill is about $25
    I would not do it for less than $65-$75
    It has to be a starting tap and not left handed thread.
    Last edited by deltaenterprizes; 07-11-2018 at 10:37 PM.

  3. #3
    Boolit Master

    Join Date
    Jun 2009
    Location
    North central Ohio
    Posts
    834
    Were me, I'd find a soul with a lathe, mount it on a face plate, bore and thread it. Fairly straight forward job. It would take a pretty good man to turn a tap that size without the proper equipment.
    Before you embark on a journey of revenge, dig two graves.

    ― Confucius

  4. #4
    Boolit Master


    Join Date
    Sep 2007
    Location
    longview,tx
    Posts
    2,553
    Quote Originally Posted by Jeff Michel View Post
    Were me, I'd find a soul with a lathe, mount it on a face plate, bore and thread it. Fairly straight forward job. It would take a pretty good man to turn a tap that size without the proper equipment.
    That is another way to do that, still time consuming setting up face plate, cost would be about the same.

  5. #5
    Boolit Master


    Nueces's Avatar
    Join Date
    Dec 2006
    Location
    Texas Hill Country
    Posts
    1,739
    Those Redding turrets are quite heavy and it would take a pretty good sized lathe to swing one offset to center a die hole. A well equipped job shop would likely use a mill to bore (not drill) the holes, then thread mill the threads, perhaps finishing with a tap. These are not bolt holes. Alignment and concentricity are important here. The threads leave nothing with which to directly pick up the hole centers without some tooling and experience. Technical papers have been published on establishing the location of threaded holes.

    If I just had to do this here, I'd set up the turret in my Myford's milling attachment. That would give me power feed to bore the holes and I could thread with a boring head in the headstock. I'd make a location gauge with a close fit in the original threads and a concentric hole. Very slow, but effective.

    Either slow/effective or faster in a professional set up would be expensive if farmed out because each hole is it's own job. The factory surely uses computer machinery.

  6. #6
    Boolit Master
    Join Date
    Feb 2007
    Location
    South West Ohio
    Posts
    1,457
    Quote Originally Posted by Nueces View Post
    Those Redding turrets are quite heavy and it would take a pretty good sized lathe to swing one offset to center a die hole. A well equipped job shop would likely use a mill to bore (not drill) the holes, then thread mill the threads, perhaps finishing with a tap. These are not bolt holes. Alignment and concentricity are important here. The threads leave nothing with which to directly pick up the hole centers without some tooling and experience. Technical papers have been published on establishing the location of threaded holes.

    If I just had to do this here, I'd set up the turret in my Myford's milling attachment. That would give me power feed to bore the holes and I could thread with a boring head in the headstock. I'd make a location gauge with a close fit in the original threads and a concentric hole. Very slow, but effective.

    Either slow/effective or faster in a professional set up would be expensive if farmed out because each hole is it's own job. The factory surely uses computer machinery.
    So....does that mean you could/would do it?

    The good thing about science is that it's true no matter if you believe it or not. (Neil DeGrasse Tyson)

    I was scolding my 5-year old for her and her friends making a giant mess in her room. She said they all did it. So I asked her: If all her friends jumped off a cliff, would she do it too? She said, "Oh no daddy! I would go to the bottom and try to catch them! They're my friends." Man, either I have a great kid or she has a stupid father.

  7. #7
    Boolit Master


    Nueces's Avatar
    Join Date
    Dec 2006
    Location
    Texas Hill Country
    Posts
    1,739
    Quote Originally Posted by AbitNutz View Post
    So....does that mean you could/would do it?

    Heh! From long experience, if I let myself give in to enthusiasm and say yes, we'd be looking at months of "Soon, Buddy, soon!"

    In your shoes, I would get on one of the home machinist boards and see if some sort of trade could be worked out. You might get to inspect a nice shop and observe some of the work.

    http://bbs.homeshopmachinist.net/forum.php
    http://www.chaski.org/homemachinist/index.php
    https://www.hobby-machinist.com
    https://www.homemodelenginemachinist.com

    Another idea would be to create a post asking for brainstorming on how to do this with nothing but basic equipment. That would be interesting and require nothing but gray cells and keyboard time.

  8. #8
    Boolit Master


    Join Date
    Sep 2007
    Location
    longview,tx
    Posts
    2,553
    What is your purpose for doing it?

  9. #9
    Boolit Master Nobade's Avatar
    Join Date
    May 2005
    Location
    Albuquerque, Nuevo Mexico
    Posts
    4,481
    I'd find someone with a modern cnc mill who could do that job with a threadmill rather than try to do it in a lathe. Once it's programmed and indicated it would only take a few minutes and all the holes would be pointed in the same direction.
    "Quemadmoeum gladis nemeinum occidit, occidentis telum est."

  10. #10
    Boolit Master
    Join Date
    Feb 2007
    Location
    South West Ohio
    Posts
    1,457
    Quote Originally Posted by deltaenterprizes View Post
    What is your purpose for doing it?
    I several dies that are that size that I want to use this press for. They're the old, big Nitro Express dies. Impossible to find and when you do, you have to mortgage your house. I want to use my T-7 press....personal preference.
    The good thing about science is that it's true no matter if you believe it or not. (Neil DeGrasse Tyson)

    I was scolding my 5-year old for her and her friends making a giant mess in her room. She said they all did it. So I asked her: If all her friends jumped off a cliff, would she do it too? She said, "Oh no daddy! I would go to the bottom and try to catch them! They're my friends." Man, either I have a great kid or she has a stupid father.

  11. #11
    Boolit Master
    Join Date
    Feb 2007
    Location
    South West Ohio
    Posts
    1,457
    I understand that eBay has a myriad of taps...can someone point me to the exact ones that I would need? I'm going to get a machinist to do this so I would assume he's going to use a milling machine. If not, I'll be going to one that does.

    I have been steered away left hand taps...I'd really like to be pointed to precisely what will do the job.

    Thanks for your overly kind indulgence.
    The good thing about science is that it's true no matter if you believe it or not. (Neil DeGrasse Tyson)

    I was scolding my 5-year old for her and her friends making a giant mess in her room. She said they all did it. So I asked her: If all her friends jumped off a cliff, would she do it too? She said, "Oh no daddy! I would go to the bottom and try to catch them! They're my friends." Man, either I have a great kid or she has a stupid father.

  12. #12
    Boolit Master
    Join Date
    Jan 2010
    Location
    South Louisiana
    Posts
    448
    Sorry, I replied in your thread in swaging.
    That toolhead is likely hardened and will require the use of carbide. Carbide taps are expensive and break easy. A quick swipe with a file will tell you how hard. I seriously doubt that a HSS tap would do more than one hole if that plus requiring a 3 foot long tap wrench to push it. Not only that you need **** near perfect alignment and squareness and a tap unless held rigidly held and aligned wont give you that.
    Your options are to set up on a faceplate in a 16" swing lathe and bore and single point each hole requiring 7 set ups to do so, that's the time consuming and expensive part, the boring and threading takes a few minutes.
    FInd a shop with a cnc vertical mill with thread milling capability. They will knock it out faster than a manual job shop and cheaper.
    NRA High Master XTC
    DR# 2125

  13. #13
    Boolit Master

    Join Date
    Mar 2013
    Location
    Northwest Ohio
    Posts
    8,873
    A manual vertical mill (Bridgeport style) can do this job. set up the t-7s head flat and true. Use a tread mandrel to indicate hole in ( this will need to be made with a good fit on the threads and a taper matching the threads chamfer). a slightly under sized end mill used first to open hole up close ( 1" then a boring head used to bore to tap drill size. Left hand taps cut a left hand thread. What you want is a right hand tap in standard size. There are +005 +010 and +.015 for holes to be het treated. Also there are -.005, -.010 and -.015 for threads to be lapped or ground for fit. You want a 000 right hand tap. On a tap this big a skip tooth desighn really lowers force to cut the thread. SInce this is a thru hole a starting tap can do it start to finish.

    With the proper set up this job can be done in a heavy drill press even. Indicate turret hole in to zero and strap clamp down. this requires some tapping around to get right. drill it to tap drill size chamfer and tap. I recommend boring as it wont walk and the radial forces distortion are much less. But it can be done with a drill. the issue will be going from 7/8 14 to 1 3/32 tap drill size the drill will want to grab and bite a lot. and end mill is better here and will cut cleanly but not in the drill press.

    Most shops will set this up and have it done in a short time. Its more set up than work, like a lot of things. the right tools and things go quick.

    I would set this up in the mill on 1-2-3 blocks with the head 2" above the table and strap clamps to lock it down. indicate hole in with the above mandrel and open up hole with 1" end mill, then bore to tap drill size and chamfer the top of the hole. Tap with a skip tooth right hand tap thru. remove and chamfer the bottom side of the thread.

  14. #14
    Boolit Master
    JSnover's Avatar
    Join Date
    Dec 2007
    Location
    Bensalem, PA
    Posts
    3,341
    What Country Gent said. It's a simple job and actually fairly easy IF you understand the importance of the locations and how to keep everything true.
    Warning: I know Judo. If you force me to prove it I'll shoot you.

  15. #15
    Boolit Master


    Join Date
    Sep 2007
    Location
    longview,tx
    Posts
    2,553
    Quote Originally Posted by Nueces View Post
    Those Redding turrets are quite heavy and it would take a pretty good sized lathe to swing one offset to center a die hole. A well equipped job shop would likely use a mill to bore (not drill) the holes, then thread mill the threads, perhaps finishing with a tap. These are not bolt holes. Alignment and concentricity are important here. The threads leave nothing with which to directly pick up the hole centers without some tooling and experience. Technical papers have been published on establishing the location of threaded holes.

    If I just had to do this here, I'd set up the turret in my Myford's milling attachment. That would give me power feed to bore the holes and I could thread with a boring head in the headstock. I'd make a location gauge with a close fit in the original threads and a concentric hole. Very slow, but effective.

    Either slow/effective or faster in a professional set up would be expensive if farmed out because each hole is it's own job. The factory surely uses computer machinery.
    You put a counterweight on the opposite side to balance out the part being off center.

  16. #16
    Boolit Master


    Nueces's Avatar
    Join Date
    Dec 2006
    Location
    Texas Hill Country
    Posts
    1,739
    Quote Originally Posted by deltaenterprizes View Post
    You put a counterweight on the opposite side to balance out the part being off center.
    Yes, of course. I was talking about the swing required. It's less than I thought. I went out and measured mine and found that a 10 inch lathe could handle it. That means my Myford 7" could take it in the 10" gap on a faceplate.

    Filed away in case I ever suffer form this particular wild hair.

  17. #17
    Boolit Man
    Join Date
    Jan 2008
    Posts
    106
    Probably a long shot.......ask Redding?

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