raw stock .379 O.D. round. Need to bring to .3753-.3757. Hollow Mill? Burnishing tool - Page 2
Close
Login to Your Account
Page 2 of 2 FirstFirst 12
Results 21 to 38 of 38
  1. #21
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    26,836
    Post Thanks / Like
    Likes (Given)
    7273
    Likes (Received)
    9180

    Default

    As for a retractable box toy, I'm guessing that Wendal @ AMSCO (dead now, and now owned by Champion (nephew)) could set you up with one.
    If not, check:

    Shorty's Tooling
    Detroit Automatic
    Champion Screw Machine
    Maybe even Champion Fortune



    -------------

    I am Ox and I approve this h'yah post!

  2. #22
    Join Date
    Sep 2011
    Location
    Posts
    1,908
    Post Thanks / Like
    Likes (Given)
    257
    Likes (Received)
    183

    Default

    Look at Tangi flow toolholders,no return mark guaranteed.
    You cannot index off the top of the turn lobe with a v toolholder because you have straight line withdrawal which will leave a return mark.
    The 'V' rest toolholder you are looking at is for cutting brass,no swarf under the rollers.
    I cannot imagine that a hollow mill will be any good, too many turning marks.
    I have a fair bit of B&S skiving tool literature if you are interested just about.

  3. #23
    Join Date
    Feb 2005
    Location
    Hatch, NM Chile capital of the WORLD
    Posts
    9,447
    Post Thanks / Like
    Likes (Given)
    15637
    Likes (Received)
    11396

    Default

    This method probably won't work with the given tolerances, but it worked in my situation,
    so.. since its cold and the shop isn't warmed up yet, might as well tell a story.

    Many moons ago, had some hot rolled 1/2" that had to come down to 485-490. I had done
    the job one time previous with a tool post grinder, but grinding the scale made a huge
    mess, so I chopped the material up and tossed it in a coffee can and filled it with
    vinegar to eat the scale away...

    I put it under the bench and was going to do it the following day.. But some stuff
    came up and I forgot about that coffee can for 2 weeks. When I finally did remember
    it, I was a little scared, the vinegar was black, but the parts were clean, and the
    vinegar had gone to work on the steel. All the parts came in at 486-487. Completely
    accidental and complete dumb luck that the parts had been chem-milled(turned?).

    That mistake made that job really easy, it just needed to be brought to length and
    one cross hole drilled.

  4. Likes Ox liked this post
  5. #24
    Join Date
    Mar 2019
    Country
    UNITED STATES
    State/Province
    Massachusetts
    Posts
    338
    Post Thanks / Like
    Likes (Given)
    179
    Likes (Received)
    156

    Default

    Quote Originally Posted by camscan View Post
    Look at Tangi flow toolholders,no return mark guaranteed.
    You cannot index off the top of the turn lobe with a v toolholder because you have straight line withdrawal which will leave a return mark.
    The 'V' rest toolholder you are looking at is for cutting brass,no swarf under the rollers.
    I cannot imagine that a hollow mill will be any good, too many turning marks.
    I have a fair bit of B&S skiving tool literature if you are interested just about.
    I remember looking at this holder in the past. I will have to look again.

    I will have to check with one of my swiss shops to see if they grind in house. I know one of them does but they are ion the other direction.

    I am sure this will be so much easier once I get approved. I will get to talk to someone in the machine shop to see how they currently do it with the same material.

    Anyone have suggestions for a small grinder to get for these in house scenarios? I am lost on the grinding side of things. I only grind my own form tools/cutoff tools and drills.

  6. #25
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    26,836
    Post Thanks / Like
    Likes (Given)
    7273
    Likes (Received)
    9180

    Default

    #2 Cinci Centerless would be way more than needed for most of your apps.
    But my love is for the #3 that can hog a lot more and hold size too, but that;'s more than you need for most apps.


    --------------

    I am Ox and I approve this h'yah post!

  7. Likes Ziggy2 liked this post
  8. #26
    Join Date
    Apr 2005
    Location
    Beaverdam, Virginia
    Posts
    9,456
    Post Thanks / Like
    Likes (Given)
    1272
    Likes (Received)
    4878

    Default

    Can skive tools be used on steel? I worked at an aerospace connector house long ago in a land far away where they used skive tools on the AS-14 Torno multi-spindles, and the Acme Gridley multis. They only ran small diameter bar stock of 3/8" and under and nothing but 360 brass, leaded copper and leaded nickel copper. For the record I never ran either of those beasts.

  9. #27
    Join Date
    Mar 2019
    Country
    UNITED STATES
    State/Province
    Massachusetts
    Posts
    338
    Post Thanks / Like
    Likes (Given)
    179
    Likes (Received)
    156

    Default

    Quote Originally Posted by Dualkit View Post
    Can skive tools be used on steel? I worked at an aerospace connector house long ago in a land far away where they used skive tools on the AS-14 Torno multi-spindles, and the Acme Gridley multis. They only ran small diameter bar stock of 3/8" and under and nothing but 360 brass, leaded copper and leaded nickel copper. For the record I never ran either of those beasts.
    My dad is leaning toward a skive tool. He has experience with them from his multi spindle days. I guess you can make them pretty easily.

    I think you put a roller on the tool and it sits on the material and allows the tool to cut concentric.I believe on the multi spindles they could hold .0005 all day. Its a way to hog out material and then get it to tolerance quickly. Dropping parts every 5-6 seconds.

  10. #28
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    26,836
    Post Thanks / Like
    Likes (Given)
    7273
    Likes (Received)
    9180

    Default

    Sounds like you are talking about a "shave" tool, and sure, you can hold that tol, but typically you would hit that on an already turned surface. Yeah, I've done it on bar surface before, and since you are only talking .002, then that's not an issue.

    But I have never ran a form tool in 4140. let alone a shave.

    Are you planning on changing gears?
    You are going to want to have your speed up for a carbide chmf and cut-off eh?
    But a Rex form on 4140 isn't going to be anywhere near that SFM.

    I would be very interested to hear your outcome, but a form and shave in 4140 would not be my go-to, but again - I aint done it before...


    ------------------

    Think Snow Eh!
    Ox

  11. #29
    Join Date
    Dec 2014
    Country
    UNITED STATES
    State/Province
    Washington
    Posts
    257
    Post Thanks / Like
    Likes (Given)
    439
    Likes (Received)
    120

    Default

    Skiving may be the low cost route to go. Made well it should hold tolerance until you get the right process up.

    To my understanding; Skiving tools are tangential cutting tools where as "shave" tools are basically a form tool intended to kiss the finial profile. schwanog has some good examples of each.

  12. #30
    Join Date
    Mar 2019
    Country
    UNITED STATES
    State/Province
    Massachusetts
    Posts
    338
    Post Thanks / Like
    Likes (Given)
    179
    Likes (Received)
    156

    Default

    Quote Originally Posted by Ox View Post
    Sounds like you are talking about a "shave" tool, and sure, you can hold that tol, but typically you would hit that on an already turned surface. Yeah, I've done it on bar surface before, and since you are only talking .002, then that's not an issue.

    But I have never ran a form tool in 4140. let alone a shave.

    Are you planning on changing gears?
    You are going to want to have your speed up for a carbide chmf and cut-off eh?
    But a Rex form on 4140 isn't going to be anywhere near that SFM.

    I would be very interested to hear your outcome, but a form and shave in 4140 would not be my go-to, but again - I aint done it before...


    ------------------

    Think Snow Eh!
    Ox
    I dont really play with carbide much but I do have some carbide cutoff tools. I would use them if I didnt have to go to dead center. They chip too easily in my world. I have plenty of Tantung cutoff blades to last 3 more lifetimes and they have worked great so far.

    I ran some 440c SS recently and had to slow things way down. The material held tolerance and ran the same drill (.1875" HSS) for 2500 holes. I ran the cross slides in by hand a bunch and it felt like it cut easy if you just let the tool do its thing. Nice Chips, Not sharp.

    I guess 41xx steels cut similar. I dont cut much of it but it was always run on my machines over the years.

    I have a ring from them to do as well. It is .746"-.748" O.D. Probly about .375" wide with a 14mm hole. They gave me .812 4140 for this one. I can run my Tantung cutoff on my vertical slide, 45 deg. chamfer on back slide, and a flat form/skive/Tantung straight edge to bring it down to size on the front slide. I can run 3 tools in the cut on this one.

    I can always get a form tool made to chamfer and bring O.D. to size. It would be consistent too. I could get around 200k parts out of it most likely. Less headaches that way too.

    I can get Form Tools in M2, M42, T15, etc. I would go with M42 for this material. I would run at around 60 SFM +/-5. I would load a new bar every 2 hours and walk away. These are the jobs my machines were made for.

  13. #31
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    26,836
    Post Thanks / Like
    Likes (Given)
    7273
    Likes (Received)
    9180

    Default

    Per the form or shave on the 3/8 part, my #1 concern would be for size and finish.
    4140 seems to like to rip and tear I would think.
    Start to leave lines in the tool, etc...

    If you doo go this route, I would ask that you post your short and long term results.


    -----------------

    I am Ox and I approve this h'yah post!

  14. #32
    Join Date
    Mar 2019
    Country
    UNITED STATES
    State/Province
    Massachusetts
    Posts
    338
    Post Thanks / Like
    Likes (Given)
    179
    Likes (Received)
    156

    Default

    Quote Originally Posted by Ox View Post
    Per the form or shave on the 3/8 part, my #1 concern would be for size and finish.
    4140 seems to like to rip and tear I would think.
    Start to leave lines in the tool, etc...

    If you doo go this route, I would ask that you post your short and long term results.


    -----------------

    I am Ox and I approve this h'yah post!
    I could always feed the part out 3-4 times and make a .250 wide form to bring it to size closer to the collet.

    Now I am just brainstorming. This will eventually be ground to size for me in production. I have to make 100 of these and 300 rings that they will pay me for. I will do the pins by hand to get what I need.

  15. #33
    Join Date
    Dec 2011
    Country
    UNITED STATES
    State/Province
    Illinois
    Posts
    213
    Post Thanks / Like
    Likes (Given)
    44
    Likes (Received)
    59

    Default

    In regards to a small grinder to buy, I agree with Ox that a #2 Cincinnati is probably the most popular and capable, but it's not really small. Maybe look into Royal Master grinders. They are tiny compared to the #2.

  16. #34
    Join Date
    Mar 2019
    Country
    UNITED STATES
    State/Province
    Massachusetts
    Posts
    338
    Post Thanks / Like
    Likes (Given)
    179
    Likes (Received)
    156

    Default

    I am working today to try to get ahead on things. I have a Drill and Reamer for the ring coming in tomorrow ($50). I found a couple of cams that will work for the rings but 1 of them has no recess lobe and the other has no reaming lobe. Not a big deal as I can 2nd op them easily in smaller quantities.

    So the rings job is a .566-.568 hole with .746-.748 O.D. The material they gave me is .812". I have to run it on a #2 1.250" machine. 64 finish on the o.d. and hole.

    I am into this one for 50 bucks. I can have a cam made for just shy of $300 to do it one and done. I will have to see production quantities and such. I also think I should get a general cam made for rings. Make it a little longer on each lobe to cover any longer rings that come across my desk (I have seen 5 of them in the last 2 months from 5 customers in 5 sizes in 5 different materials) and just use the same cam for shorter ones as well.

    I did see a video of there facilities and they showed the heat treatment facilities and they showed them pushing parts through a centerless grinder. I now know they have one in house for sure and it should just be a matter of talking to the right person. One of the other parts I am not doing for the trial had a "vendor print" pre heat treat, and an in house print post H.T.

    So if it all plays out like it should I wont have to put much of my own money up for anything and I can run rings and chamfer cutoff pins on a dedicated machine just for them. I think they will be happy with that situation and it works for me as well. Just another low dollar job churning parts out slowly day in and day out.

  17. #35
    Join Date
    Sep 2011
    Location
    Posts
    1,908
    Post Thanks / Like
    Likes (Given)
    257
    Likes (Received)
    183

    Default

    I have reconsidered the Tangi flow type turning box and it is a no no.
    In order to work the tool bit has to touch the stock first in order to push the tool bit back against the toolholder. You do not have enough stock for this to happen so it's a no go.
    I now prefer the shaving method.
    Last edited by camscan; 11-08-2020 at 10:57 AM. Reason: Can't spell toolbit

  18. #36
    Join Date
    Sep 2011
    Location
    Posts
    1,908
    Post Thanks / Like
    Likes (Given)
    257
    Likes (Received)
    183

    Default

    Do you have a longitudinal turn attachment on a 00?

  19. #37
    Join Date
    Mar 2019
    Country
    UNITED STATES
    State/Province
    Massachusetts
    Posts
    338
    Post Thanks / Like
    Likes (Given)
    179
    Likes (Received)
    156

    Default

    Quote Originally Posted by camscan View Post
    Do you have a longitudinal turn attachment on a 00?
    Not that I am aware of.

    I did get 5 of the "00" machines in my back room now. They all have slotting attachments. They are wired for 460v but I can wire it for 208 pretty easily. I will be playing with these in a few weeks. I will know what I have soon.

  20. #38
    Join Date
    Mar 2019
    Country
    UNITED STATES
    State/Province
    Massachusetts
    Posts
    338
    Post Thanks / Like
    Likes (Given)
    179
    Likes (Received)
    156

    Default

    Quote Originally Posted by Ox View Post
    Per the form or shave on the 3/8 part, my #1 concern would be for size and finish.
    4140 seems to like to rip and tear I would think.
    Start to leave lines in the tool, etc...

    If you doo go this route, I would ask that you post your short and long term results.


    -----------------

    I am Ox and I approve this h'yah post!
    I just ran the ring today and got some interesting results.

    I found a flat/form carbide tool to bring the size from .812 to .747

    I noticed the material is "tearing" a bit. Even with a short dwell it looks a little torn. Holds tolerance good though.

    The 14mm hole I had at probably .01+ IPR at first. Backed it off a bit and upped the SFM a bit. Got better results but still got too thick of a chip. Need less aggressive feed but am good at 66 SFM with a chinese HSS jobber 14mm drill. When run hard the material got shiny. After searching here it seems 4140 can work harden. Looks like a good finish when this happens.

    Gotta ream it by hand tomorrow. I will get a good feel for how it cuts for sure.

    Some more research shows .005 IPR would be the best for longevity. I agree fully from todays results.

    Looks Like
    RPM 460
    SFM 66
    IPR .005

    HSS Twist Drill - 14mm
    4140 Alloy, Cold drawn, Annealed.
    Is the data were looking for. Enjoy.


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •