Recommend a boring bar for mass material removal - Page 3
Close
Login to Your Account
Page 3 of 8 FirstFirst 12345 ... LastLast
Results 41 to 60 of 160
  1. #41
    Join Date
    May 2011
    Country
    UNITED STATES
    State/Province
    New Jersey
    Posts
    1,922
    Post Thanks / Like
    Likes (Given)
    173
    Likes (Received)
    1042

    Default

    I have a .563" hertel carbide bar that takes wpgt "Trigon" inserts. You can take some pretty big cuts with it. If you have coolant available it's through as well.

  2. #42
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    25,080
    Post Thanks / Like
    Likes (Given)
    5316
    Likes (Received)
    7836

    Default

    Quote Originally Posted by Zahnrad Kopf View Post
    We have a turning job that will require installing a 4.5" bore in solid material, among other ID and OD features. Due to timing, there is no time to entertain having the blanks water-jetted to a nominal bore size for cleanup in the turning center. Plus, the price won't allow it.

    So, with that said we're looking for recommendations on a boring bar and insert combo that might help us remove material faster than we might normally. Machine is 15HP spindle with gear drive transmission, so I think the power is there. And, it's as stout as any other machine in its size range that I have ever run. So, I'm not worried about that. However, since the vast majority of what we do is typically MUCH smaller and not usually removing this much material, I'm not really sure what I can expect to achieve. Right now, I am thinking to hold it in Pie jaws since I am only going to get .500" to hold onto. ( which obviously will also have effect on how large a cut we can take ) Part gets flipped for 2nd op install of feature on other face.

    Material is 4140 Pre Hard. 6" diameter, solid. 2.125" thick. Any recommendations on a tool/insert combo?

    Thanks.

    Got these done yet?

    You said that there wasn't time to punch the centers out with the torch. That seems like you need to make chips "yet today".

    ???


    Now I hafta question torching 4140PH in the firth place.
    Shirley that would need annealed afterwards eh?
    Then re-heat treated back to "PH" status?

    Besides, the cost of blowing that center out can either go to your material suppliers torch, or to your lathe.
    I see folks all the time here trying to minimize the amount of werk that they have to doo to a part. I doubt that I will ever understand that train of thought? I am in the business of selling machine time. I'm all about blowing that center out on my own if it pencils out at all.

    That low range will really help that 15hp grow up on this job!



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

    Think Snow Eh!
    Ox

  3. Likes Monarchist, doug925 liked this post
  4. #43
    Join Date
    Nov 2013
    Country
    UNITED STATES
    State/Province
    Utah
    Posts
    4,373
    Post Thanks / Like
    Likes (Given)
    1170
    Likes (Received)
    2397

    Default

    Quote Originally Posted by Dan from Oakland View Post
    Using the outside insert of an insert drill for more than a few parts is penny wise and pound foolish. Not saying you can't do it but drill inserts tend to be a lot more expensive than a turning insert. AND/BUT there is no way you can cut as hard or fast using a drill body for a boring bar- drill bodies are designed to handle the thrust from drilling and are no where near as rigid as a boring bar as they don't have or need flutes for chip evacuation.
    I agree with this in the context of any "more than a few parts". BUT man is it nice if you just have few parts. If you are smart about indexing the square type inserts (Iscar and others) the inside corner of the inside insert gets almost no wear as a result of near zero/infinite SFM, so indexing that corner to the Boring sequence works okay. but you really need to be attentive.

    I do it all the time, but I am lazy.

    Robert

  5. #44
    Join Date
    Apr 2010
    Country
    UNITED STATES
    State/Province
    Wisconsin
    Posts
    6,010
    Post Thanks / Like
    Likes (Given)
    4155
    Likes (Received)
    3661

    Default

    Quote Originally Posted by Dan from Oakland View Post
    Using the outside insert of an insert drill for more than a few parts is penny wise and pound foolish. Not saying you can't do it but drill inserts tend to be a lot more expensive than a turning insert. AND/BUT there is no way you can cut as hard or fast using a drill body for a boring bar- drill bodies are designed to handle the thrust from drilling and are no where near as rigid as a boring bar as they don't have or need flutes for chip evacuation.
    I agree with the intent of this, but for what we're doing I think it would be okay. I'm not talking about using a ten year old insert drill to bore open to 4.5". I'm more considering using a modern insert drill with this type of use accommodated for. ( and expected ) Additionally, I'm only considering the use for a few passes, only to open marginally up to a larger boring bar size. So, in essence, using a 1.25" insert drill to open up enough to allow a 1.5" boring bar in to continue the bulk of the work.

    I am not completely committed to the idea, yet. However, it does have some merit and is worth investigating.


    Quote Originally Posted by Ox View Post
    Got these done yet?
    No, Sir. Not yet... almost. We won't get the material from them until Tuesday some time.


    Quote Originally Posted by Ox View Post
    You said that there wasn't time to punch the centers out with the torch. That seems like you need to make chips "yet today".

    ???


    Now I hafta question torching 4140PH in the firth place.
    Shirley that would need annealed afterwards eh?
    Then re-heat treated back to "PH" status?

    Besides, the cost of blowing that center out can either go to your material suppliers torch, or to your lathe.
    I see folks all the time here trying to minimize the amount of werk that they have to doo to a part. I doubt that I will ever understand that train of thought? I am in the business of selling machine time. I'm all about blowing that center out on my own if it pencils out at all.
    No, no... I wrote that there was not time for water-jetting the cores out. Absolutely no way I am going to be torching out cores in 4140 just to deal with that headache.


    Quote Originally Posted by Ox View Post
    That low range will really help that 15hp grow up on this job!
    LOL. That's what I'm hoping, buddy.


    It's funny to me... Given the nature and size of the vast majority of our work, this machine very rarely sees the low range get selected. So, I'm a little out of my auto-pilot realm, but looking forward to expanding it a bit.


    Quote Originally Posted by litlerob1 View Post
    I agree with this in the context of any "more than a few parts". BUT man is it nice if you just have few parts. If you are smart about indexing the square type inserts (Iscar and others) the inside corner of the inside insert gets almost no wear as a result of near zero/infinite SFM, so indexing that corner to the Boring sequence works okay. but you really need to be attentive.

    I do it all the time, but I am lazy.

    Robert
    I tell people this all the time. I'm lazy. So I really bristle at having to do something more than once that should have only been done once, if done correctly. It's not that I'm good or even smart. It's that I'm lazy! LOL.

    Thanks, Gentlemen.

    P.S.,

    I did do some cursory searching on some aggressive serration claw jaws. Between the schedule timing of this job and their costs, I will most likely just use Pie jaws for this time around. But I like the idea so will very likely make some of my own claw jaws with OD gripping pointy serrations.

  6. Likes Monarchist liked this post
  7. #45
    Join Date
    Feb 2007
    Location
    Aberdeen, UK
    Posts
    3,501
    Post Thanks / Like
    Likes (Given)
    1217
    Likes (Received)
    1308

    Default

    Bit late to this party, but I do a massive amount of this kind of work with this kind of material, although this is a pretty small part on my scale.

    Claw Jaws are absolutely the way to hold a part like this.

    The Allied Revolution drills are useless in the bigger sizes. I have a 100mm one, it was an expensive tool and a complete waste of money. Too much surface speed delta between the inner and outer insert for those little inserts. It just doesn't work, constant balancing act between not burning up the outer insert, not breaking the inner insert, and actually getting enough feed to break a chip without shattering the inner insert from too much pressure.

    Forget about trepanning - slow, needs a lot of torque, difficult chip control, expensive tooling.

    Spade drills are cheap, but any modern insert drill will run circles around it.

    Wxxx inserts are useless for anything apart from very light roughing. There's just no locational stability in the pocket.

    Sandvik 880 is still my first choice for real heavy duty drilling. Expensive, but justifiably so. Probably not necessary if your lathe is unable to reach the limits of the tool however.

    Follow up with a CNMG or DNMG to bore. DNMG150612 is a good choice as it can still break a chip with pretty big DOC (6-7mm DOC) and is less prone to chatter than CNMG.
    Last edited by gregormarwick; 09-24-2017 at 08:12 AM.

  8. Likes Monarchist, Jashley73, CNC Hacker liked this post
  9. #46
    Join Date
    Apr 2007
    Location
    Pillager, MN
    Posts
    5,703
    Post Thanks / Like
    Likes (Given)
    1861
    Likes (Received)
    5174

    Default

    This is darn simple turning........................tree panning? Really? Spade drills? Wah? It's 2017 for cryin out loud. Get a 2" indexable, a nice beefy 1.5" CNMG bar, serrated hard jaws and have at it. The material is butter. 4140PH? Cuts better than 1018..............I may not be able to plow through it like a machine with low range, but even my wimpy Haas could chew through a pile of iron at a good clip..........................

  10. Likes ARB, Mud, Jashley73, CNC Hacker liked this post
  11. #47
    Join Date
    Sep 2017
    Country
    ITALY
    Posts
    23
    Post Thanks / Like
    Likes (Given)
    1
    Likes (Received)
    2

    Default

    Quote Originally Posted by gregormarwick View Post
    wxxx inserts are useless for anything apart from very light roughing. There's just no locational stability in the pocket
    a32s-dwlnr08 : wnmg + shim + top clamp + internal coolant

    i use such tools inside custom toolholders : lower height, heat treated, bigger clamping screws, etc

    sometimes chips get stuck between insert and top clamp, but this is ok as long as there is a roughing operation

  12. #48
    Join Date
    Nov 2013
    Country
    UNITED STATES
    State/Province
    Utah
    Posts
    4,373
    Post Thanks / Like
    Likes (Given)
    1170
    Likes (Received)
    2397

    Default

    Quote Originally Posted by kalim View Post
    a32s-dwlnr08 : wnmg + shim + top clamp + internal coolant

    i use such tools inside custom toolholders : lower height, heat treated, bigger clamping screws, etc

    sometimes chips get stuck between insert and top clamp, but this is ok as long as there is a roughing operation
    It's like arguing with a ------cat or a kitten??

  13. Likes Jashley73 liked this post
  14. #49
    Join Date
    Apr 2010
    Country
    UNITED STATES
    State/Province
    Wisconsin
    Posts
    6,010
    Post Thanks / Like
    Likes (Given)
    4155
    Likes (Received)
    3661

    Default

    Quote Originally Posted by gregormarwick View Post
    Follow up with a CNMG or DNMG to bore. DNMG1501612 is a good choice as it can still break a chip with pretty big DOC (6-7mm DOC) and is less prone to chatter than CNMG.
    So, I'm leaning more toward a DNMG insert than a CNMG insert simply for the versatility and tool pocket economy. Okay, okay... I don't really need to watch my tool pocket usage... There are 12. Just that if I can avoid an additional tool, it makes sense. The reason is that these bores have relief bores in them, along with 45° chamfers so I am thinking that as long as we have to purchase tooling, I may as well purchase one tool that can do the whole thing instead of two tools and inserts to match.

    I honestly do not recall using a DNMG bar before, but I'm a fan of multi clamps. I don't mind the extra fiddling when changing inserts, at all. But given the depth of the pocket and the steep DNMG shape, is the top clamp a necessity? I ask, because it sure seems to limit our choices fairly largely when deciding to have one. I know that I'd sure feel better with one, but maybe I'm letting experiences with other tools color my opinion, so thought to ask.

    Looking forward to hearing back from the reps on Monday. Also tried to email Exkenna Curtis again to see if our accounts will play nice. Also kind of looking forward to seeing how this old thing runs in low gear, slow speed, and much heavier ( than we normally deal with ) cuts... Almost like getting another machine...

  15. Likes Monarchist liked this post
  16. #50
    Join Date
    Mar 2017
    Country
    CHINA
    Posts
    1,576
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1132

    Default

    Quote Originally Posted by david n View Post
    This is darn simple turning........................tree panning? Really? Spade drills? Wah? It's 2017 for cryin out loud.
    Well, yes, but ... to throw the capitalist Eli Goldratt viewpoint in here, if you are a small shop and go to auctions :

    Spade drill body, $10. Probably get a box of two or three sizes for $15 - 20.

    The hss inserts, even if you buy them new from Coast Tool, still only $15-20 apiece. (My prices could be off on this.)

    Resharpen by hand easy.

    So the job comes in, you throw the antique spade drill up, pump the coolant directly through it, blow out the center holes in the morning. Yeah, it takes longer. But your total investment was $50 about three years ago when you went to the Renstrom auction. You didn't have to order anything, research catalogs, talk on phone, wait for UPS. Holes in the blanks, now move on to finishing the parts.

    Get a 2" indexable, a nice beefy 1.5" CNMG bar, serrated hard jaws and have at it.
    Price ? Time ? What's the actual hangup in getting the job done ?

    Constraint theory. What is our goal and what are the real bottlenecks ?

  17. Likes Monarchist liked this post
  18. #51
    Join Date
    Sep 2017
    Country
    ITALY
    Posts
    23
    Post Thanks / Like
    Likes (Given)
    1
    Likes (Received)
    2

    Default

    Quote Originally Posted by Zahnrad Kopf View Post
    is the top clamp a necessity?
    good toolholders should allow an insert to cut without actually clamping the insert on the holder

    tightening an insert on such a holder must not be done thinking that delivered torque
    must overcome the cutting forces, but only to keep the insert in place, not to fall ( because of gravity )

    more precise, the clamp should not unscrew because of the effect created by vibrations

    during a long setup, vibrations may loose or tighten a screw ; more precise, the parts from the thread ensemble change internal tension near the thread zone

    also ensemble hardness comes into play : things are not so ok if screw and parts have almost same hardness especially if hardness is high, because is difficult to achieve that elastic-plastic behaviour on the deformation chart; for a human ( hand ) is easier to feel that point when at least one part has lower hardness

    now back to your question : is good to check screws from time to time, but is not ok to overtight an insert clamp if quality toolholders are used; consider top clamps only when machining with higher specs


  19. #52
    Join Date
    Oct 2012
    Country
    UNITED STATES
    State/Province
    Virginia
    Posts
    10,268
    Post Thanks / Like
    Likes (Given)
    5843
    Likes (Received)
    4626

    Default

    Quote Originally Posted by DMF_TomB View Post
    spade drill make a 2.5 or 3" dia hole is a good start.
    Not on this one. Too thin for the hole diameter. One runs out of point guidance right away, then shit gets ugly, and fast.

    Trepan, annular cutter, or "balanced" boring-bar head are the better methods on any material where the material thickness is less than the bore wanted.

    2CW

    And BTW.. GREAT thread, and so voted!

    Lots of good points covered, and adaptable to more than just the OP's immediate needs.

    Thank you, one and all!

  20. #53
    Join Date
    Apr 2007
    Location
    Pillager, MN
    Posts
    5,703
    Post Thanks / Like
    Likes (Given)
    1861
    Likes (Received)
    5174

    Default

    Quote Originally Posted by SeaMoss View Post
    IF you are a small shop and go to auctions :
    Could happen..........if the stars align and you bought that lottery ticket............................................ ....

    The OP prolly has none of those great auction jewels that would make the job so much easier and "cheaper".......................(and take 3-4 times as long, negating any tooling savings)

  21. #54
    Join Date
    Apr 2007
    Location
    Pillager, MN
    Posts
    5,703
    Post Thanks / Like
    Likes (Given)
    1861
    Likes (Received)
    5174

    Default

    Quote Originally Posted by Monarchist View Post
    Not on this one. Too thin for the hole diameter. One runs out of point guidance right away, then shit gets ugly, and fast.

    Trepan, annular cutter, or "balanced" boring-bar head are the better methods on any material where the material thickness is less than the bore wanted.
    Huh? Maybe a spade, but and indexable will work just fine......................they don't care how thick(or thin) the material is..................................

  22. #55
    Join Date
    Feb 2007
    Location
    Aberdeen, UK
    Posts
    3,501
    Post Thanks / Like
    Likes (Given)
    1217
    Likes (Received)
    1308

    Default

    Quote Originally Posted by Zahnrad Kopf View Post
    So, I'm leaning more toward a DNMG insert than a CNMG insert simply for the versatility and tool pocket economy. Okay, okay... I don't really need to watch my tool pocket usage... There are 12. Just that if I can avoid an additional tool, it makes sense. The reason is that these bores have relief bores in them, along with 45° chamfers so I am thinking that as long as we have to purchase tooling, I may as well purchase one tool that can do the whole thing instead of two tools and inserts to match.

    I honestly do not recall using a DNMG bar before, but I'm a fan of multi clamps. I don't mind the extra fiddling when changing inserts, at all. But given the depth of the pocket and the steep DNMG shape, is the top clamp a necessity? I ask, because it sure seems to limit our choices fairly largely when deciding to have one. I know that I'd sure feel better with one, but maybe I'm letting experiences with other tools color my opinion, so thought to ask.

    Looking forward to hearing back from the reps on Monday. Also tried to email Exkenna Curtis again to see if our accounts will play nice. Also kind of looking forward to seeing how this old thing runs in low gear, slow speed, and much heavier ( than we normally deal with ) cuts... Almost like getting another machine...
    For heavy cutting, yes get one with a top clamp. And make sure it's pullback top clamp. My experience roughing with leverlock ones is that cutting vibration will lift the insert slightly in the pocket so that the shim becomes loose, which leads to chatter. This doesn't tend to be so much of an issue on external holders, which is why I anecdotally attribute it to vibration of the tool body.

    Zahnrad, one thing that hasn't been brought up yet, but might be important - What actual lathe do you have?

    I ask because insert drills in lathes like damping and stability. Too big of a drill in too small of a turret - it will drill the hole, but will squeal like a stuck pig. Similarly, in modern turning centres, the bigger issue with spade drills (if you go that route) is not spindle torque, but Z axis thrust.

  23. Likes Jashley73, npok liked this post
  24. #56
    Join Date
    May 2002
    Location
    South Central PA
    Posts
    13,444
    Post Thanks / Like
    Likes (Given)
    2176
    Likes (Received)
    3370

    Default

    Quote Originally Posted by Zahnrad Kopf View Post
    So, I'm leaning more toward a DNMG insert than a CNMG insert simply for the versatility and tool pocket economy.
    My fear about that would be breaking the DNMG when you are pushing the bar with heavy cuts. When that happens you can wipe out the expensive bar before you know it happened. We went to CNMX when we started breaking CNMG inserts because they are 50% thicker. We also tried the LNMX inserts mentioned earlier fearing that the CNMX might not be enough, so far haven't needed it.

    Quote Originally Posted by SeaMoss View Post
    Well, yes, but ... to throw the capitalist Eli Goldratt viewpoint in here, if you are a small shop and go to auctions :

    Spade drill body, $10. Probably get a box of two or three sizes for $15 - 20.

    The hss inserts, even if you buy them new from Coast Tool, still only $15-20 apiece. (My prices could be off on this.)

    Resharpen by hand easy.

    So the job comes in, you throw the antique spade drill up, pump the coolant directly through it, blow out the center holes in the morning. Yeah, it takes longer. But your total investment was $50 about three years ago when you went to the Renstrom auction. You didn't have to order anything, research catalogs, talk on phone, wait for UPS. Holes in the blanks, now move on to finishing the parts.


    Price ? Time ? What's the actual hangup in getting the job done ?

    Constraint theory. What is our goal and what are the real bottlenecks ?
    The biggest constraint here would be backing up in the time machine to get to the auction. ZK needs the tools now. I haven't seen any auctions like that within driving distance for years. Before I stopped chasing auctions most of those bottom feeder items started being snapped up by Ebay speculators. Having been quite an auction rat, I have a huge hoard of those buys, including some spade drills that I've never used. Plus keeping and storing them for years and then finding them when desired goes against most of Goldratt. Ebay has replaced auctions for me, get it now at 40% or less instead of store it forever at 10%.

  25. Likes Monarchist liked this post
  26. #57
    Join Date
    Feb 2007
    Location
    Aberdeen, UK
    Posts
    3,501
    Post Thanks / Like
    Likes (Given)
    1217
    Likes (Received)
    1308

    Default

    Quote Originally Posted by Mud View Post
    We also tried the LNMX inserts
    You want to talk about wiping out holders, those LNMX inserts take the cake. The extreme feedrates required to break a chip mean that failures happen before most operators can react. I ran LNMX in production for about two weeks before going back to CNMG. Effective, but replacing the holders got expensive. And when you take into consideration that you're limited to about half the max DOC of a CNMG12 the gains aren't all that impressive anyway.

    Quote Originally Posted by Mud View Post
    My fear about that would be breaking the DNMG when you are pushing the bar with heavy cuts.
    In 41xx and 43xx steels with DNMG150616 I run 6-7mm DOC and .3-.4mm/r on 63mm C6 capto bars in production. Insert breakages are rare if the operator is paying attention.

  27. Likes Mud, Monarchist, npok liked this post
  28. #58
    Join Date
    Mar 2017
    Country
    CHINA
    Posts
    1,576
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1132

    Default

    Quote Originally Posted by Mud View Post
    I have a huge hoard of those buys, including some spade drills that I've never used.
    There ya go ! Ship one over to zahnrad

  29. #59
    Join Date
    Jun 2013
    Location
    St. Louis
    Posts
    653
    Post Thanks / Like
    Likes (Given)
    472
    Likes (Received)
    294

    Default

    removed .

  30. #60
    Join Date
    Jun 2016
    Country
    UNITED STATES
    State/Province
    Minnesota
    Posts
    233
    Post Thanks / Like
    Likes (Given)
    73
    Likes (Received)
    104

    Default

    I have done work like this before. If the O.d. need to be turned I roughed that, drilled the slug and bored, then finished the o.d. with a dnmg holder so then I had less resonance to worry about. I basically made a coffee can I say.

    But not to hijack thread I have a question:
    What do you do with something that already has a ...1" hole that you have to open up to around 3"??? Alot of material removal but insert drills need to center locate so a spade? Will the edges chip out? I want to run the largest bore bar I can so can't start with a pint size 1" bore bar.


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
  •