Pull Stud Broke - Brother Spindle Trashed - Page 3
Close
Login to Your Account
Page 3 of 26 FirstFirst 1234513 ... LastLast
Results 41 to 60 of 509
  1. #41
    Join Date
    Nov 2014
    Country
    UNITED STATES
    State/Province
    Florida
    Posts
    3,749
    Post Thanks / Like
    Likes (Given)
    1547
    Likes (Received)
    1770

    Default

    Quote Originally Posted by Mickey_D View Post
    We had a major crash on our fairly new (under a year old) Brother S500X1. The machine was doing a light facing operation with a Mitsubishi 2" 45 degree ASX 4 flute face mill - 10,000 rpm, .025 DOC, 150 IPM, on a 1.48" x 2.48" 6061 part. We had run about 10 parts on this run (300 plus with the same program and tools last month and over 12,000 over the last five years on at least 5 different machines - so not a new part), everything sounded fine, finish was great, and then BOOM! The machine made a bang and grinding noise for about a second before erroring out. Jogged the spindle up and noticed that the facemill was laying on top of the part with an insert stuck into the part (still clamped into the vise). I then noticed that the pull stud was broken at the base, looked for it in the machine and could not find it and did not until I looked into the spindle and noticed that it was still clamped into the spindle. The inside spindle was trashed at the spindle mouth and at the top of the taper where it spun on the tool.

    Called Yamazen to get service scheduled (this was Tuesday afternoon and they got a spindle shipped in and a service guy down and had it up by Thursday evening) so many kudos to them for prompt service. I then called Maritool support and told them that one of their 30 taper (not coolant through) studs (not more than 6 months old) failed and ate my spindle, tool holder, and facemill and that it looked like a possible problem with either material or heat treat process and they should trace the studs from our order and check any that they had. The response that I got was "they can break" and if I wanted to I could send the broken one back and they would inspect it. I have bought a lot of stuff from them over the years and have been happy but I am not now. Yamazen has gotten more aggressive on stud pricing so we are going to switch to their studs from now on - I don't like surprises.
    To me that ^ implies Yamazen is going to warranty their studs somehow?? So if you have a crash with a broken Yamazen pull stud, spindle repair is on their dime? Trying to understand the thought process since you stated you had run this job (even tho IMO 10krpm on a 2" facemill is WAAAYY too fast) of over 12k parts in 5 years, you get one catastrophic failure and you throw Maritool under the bus..

  2. Likes empwoer liked this post
  3. #42
    Join Date
    Nov 2005
    Country
    UNITED STATES
    State/Province
    Illinois
    Posts
    2,024
    Post Thanks / Like
    Likes (Given)
    210
    Likes (Received)
    1568

    Default

    " When I called Maritool before ordering about $1500 worth of ER-20 and ER-32 holders, pulls studs and a face mill holder I asked the person about what studs were needed and was told that the standard non-coolant through studs would be fine on the regular and not high torque spindle. That is whey I ordered them."

    seriously!! You are runing all these machines and running a face mill at 10,000 rpms and you are taking the advise of someone at sales? My sales team knows any questions other than simple cookie cutter answers go straight to tech, me.




    Quote Originally Posted by Mickey_D View Post
    I am not trying to bash Maritool, I have used their stuff for years and have been happy with it, but I am sharing my experience about a pull stud failure. This pull stud suffered a very quick brittle failure. No elongation, deformation, or give at all, it just snapped. I am going to dig in my junk drawer and pull out some old long and skinny Haas style through coolant studs from my Hardinge, put them in a vise and whack them with a hammer and see if they snap like these did or give a little before they fail. Some probably have over a hundred thousand cycles on them.
    Then why the nice choice of thread title?

  4. #43
    Join Date
    Oct 2004
    Location
    Elyria Ohio
    Posts
    1,804
    Post Thanks / Like
    Likes (Given)
    3396
    Likes (Received)
    749

    Default

    Quote Originally Posted by Mickey_D View Post
    I am not trying to bash Maritool, I have used their stuff for years and have been happy with it, but I am sharing my experience about a pull stud failure. This pull stud suffered a very quick brittle failure. No elongation, deformation, or give at all, it just snapped. I am going to dig in my junk drawer and pull out some old long and skinny Haas style through coolant studs from my Hardinge, put them in a vise and whack them with a hammer and see if they snap like these did or give a little before they fail. Some probably have over a hundred thousand cycles on them.
    And that will prove ...?

  5. #44
    Join Date
    Apr 2007
    Country
    UNITED STATES
    State/Province
    West Virginia
    Posts
    1,026
    Post Thanks / Like
    Likes (Given)
    504
    Likes (Received)
    408

    Default

    After reading a lot of posts here on 30 taper machines, including some pm's with BROTHERFRANK, I have fretted a lot over the use of my 2" face mills in my machine. Mostly I have backed off from using them in production because of this risk. If something goes wrong using a cutter this size it is almost guaranteed that the the spindle will be toast. Pushing it hard makes this a whole lot more likely.

  6. #45
    Join Date
    Jun 2012
    Location
    Michigan
    Posts
    4,685
    Post Thanks / Like
    Likes (Given)
    4297
    Likes (Received)
    2845

    Default

    We had to replace our spindle on our Brother just last week. Operator forgot to turn the coolant on cutting 6061 aluminum.Had the same grinding noise the OP did, then the stud busted off and after the holder danced around inside the taper for a couple of seconds it was thrown from the spindle. I didn't even need to look inside at the taper, I knew it was fucked. The tool was a 1/2" Destiny Diamondback running at 15k, 1.25 deep with .100" stepover and 400ipm.
    Part was lifted up out of the carbide grippers.
    We've ran thousands of these parts.
    Yes we use Mari-Tool pull studs. Spindle was replaced, and bought more Mari-Tool studs along with more Mari-Tool holders.
    This was 100% operator error.

    Side note to OP:
    Who makes those Yamazen pull studs?

  7. #46
    Join Date
    Oct 2004
    Location
    Elyria Ohio
    Posts
    1,804
    Post Thanks / Like
    Likes (Given)
    3396
    Likes (Received)
    749

    Default

    No matter what you do the result is going to be inconclusive. You will never be able to figure out exactly what went wrong in there.

    I remember in my metallurgy book when I was an apprentice, there was a very long explanation on the various phases that steel goes through inside a blast furnace. Then at the end of the explanation it said something to the effect of "that's our best reasonable guess since no one has actually been inside a blast furnace during the process". That has stuck with me through the years. Jumping to a conclusion is never wise and usually wrong.

    This occurrence was an anomaly - pure and simple. Had that tool holder been previously involved in a crash that went unreported? Had that tool holder been dropped on the pull stud? Had the pull stud been damaged when it was installed in the tool holder?

    I had a pull stud break and it was awful. I was in the middle of a cut with an old cemented carbide cutter (those things were awful). When it broke the boss yelled at me like I did something wrong even though it was mid-way through a production run of a job that was run periodically. Haha.. I was too young to know better but now I would call him a jackass to his face.

    Why did it break? I have no idea. In 40 years I have never broken another one.

    If you want to send that pull stud out for failure analysis that is about the only way to get any meaningful conclusion on the matter but even then it will only be marginal at best. Even if hardness is tested at various points around the part, hardness readings can vary by a couple of points either way on every reading. That is really not going to tell you anything conclusive. Looking at the microstructure may tell you where the fracture originated - but again - nothing conclusive to be learned from that. Chemical analysis will tell you if the stud is composed of the steel that it is supposed to be composed from. That may yield you something useful. A thread on practical machinist is not going to give you much help.

  8. #47
    Join Date
    Sep 2007
    Country
    UNITED STATES
    State/Province
    Washington
    Posts
    5,181
    Post Thanks / Like
    Likes (Given)
    188
    Likes (Received)
    1544

    Default

    To the OP, I am really sorry this happened. I have had some bumps with my S700X1 and it is a sickening feeling. I really do empathize .

    OK, so I have run several 10,000's of parts through my S700X1. 80% 6061, 5% 7075, and the remainder plastics and stainless. Nearly all of those parts (not the stainless) were faced with a Maritool 5-insert 2-1/2" SEHT endmill. Average .02" DOC, and up to 100% engagement. .003"-.006" chipload. I am lately using Frank's extra-strength pullstuds on this tool, but before that it was the regular ones. This is a quite light cut, compared to roughing with a 1/2" Diamondback.

    With this in mind, I rather doubt the OP's case was simply the pullstud broke with nothing else having gone sideways just before the kaboom. Earlier in the thread you said this -- "We have worn out several of the fixtures over the years (make them out of CRS 1018) and when they wear parts get flung out." Could it be that this is exactly what happened here, and the broken pullstud is a consequence?

    Again, I'm sensitive to your situation, and I want to be helpful, and not take sides. It is possible that you switch over to someone else's pullstud, run for awhile, then another part lifts out of the fixture, and you make another kaboom, and scrap another spindle.

    Regards.

    Mike



  9. Likes 2outof3, Nerdlinger, empwoer, Mateomicro liked this post
  10. #48
    Join Date
    Dec 2012
    Location
    Se Ma USA
    Posts
    1,497
    Post Thanks / Like
    Likes (Given)
    115
    Likes (Received)
    840

    Default

    Only way to tell what actually happened would be to treat the machine like a crime scene. Touch nothing and photograph everything at every angle, measure every distance, every force applied. Even then it will still be hard to determine if the broken stud was a symptom or a cause. Would a lost insert cause enough imbalance? If so the vibration would "flex" the assembly 333 time a second at 20k. It is a tapered holder and side loading forces create a lot of force pulling on the stud.
    Last year a piece of HDPE got ripped from a vacuum chuck by a .75 endmill running at 8k, bit plunged to make a pocket in the center. The CAT40 holder spun the part and imbalance pulled it out of the spindle and through part of the enclosure. $1400.00 to replace Z roller guard, serious sheet metal banging and several digs in the spindle bore. We were luck as a careful hand stoning inside the spindle restored the TIR to maybe a 10th. A part we make thousands of every year for the last 15+ years. Drawbar force was checked and OK.

  11. #49
    Join Date
    Jan 2013
    Location
    Gilbert, AZ
    Posts
    5,878
    Post Thanks / Like
    Likes (Given)
    7404
    Likes (Received)
    7467

    Default

    Quote Originally Posted by Mtndew View Post
    We had to replace our spindle on our Brother just last week. Operator forgot to turn the coolant on cutting 6061 aluminum.Had the same grinding noise the OP did, then the stud busted off and after the holder danced around inside the taper for a couple of seconds it was thrown from the spindle. I didn't even need to look inside at the taper, I knew it was fucked. The tool was a 1/2" Destiny Diamondback running at 15k, 1.25 deep with .100" stepover and 400ipm.
    Part was lifted up out of the carbide grippers.
    We've ran thousands of these parts.
    Yes we use Mari-Tool pull studs. Spindle was replaced, and bought more Mari-Tool studs along with more Mari-Tool holders.
    This was 100% operator error.

    Side note to OP:
    Who makes those Yamazen pull studs?
    In red ^^^ That is 40 taper territory. No way I would try that in my Brother.
    I run 3 tools in there that I absolutely hate having to run in there. But, part features give me no choice.
    I am quite conservative with them. Yet they are still very loud, even though the spindle load is low. I still don't like it.
    As was mentioned already, noise = vibration. Vibration = bad.

    I believe Frank sells both his own studs, and JM Performance studs.
    If you look on Maritool.com @ the BT30 studs, the "high-force" studs come from JM Performance (I'm pretty sure). I am sure Frank will chime in and correct me if I am wrong.
    I run a mix of both. For drilling/tapping/reaming/ or anything that I am sure is a very light load (chamfering with a 1/8" drill/mill) I'll run Franks studs.
    Anything that raises an eyebrow gets a high-force stud.

    The jist of the high-force stud is that it puts the threads deeper in the taper, reducing taper distortion.

  12. Likes CosmosK, D.D.Machine liked this post
  13. #50
    Join Date
    Dec 2013
    Country
    UNITED STATES
    State/Province
    California
    Posts
    683
    Post Thanks / Like
    Likes (Given)
    227
    Likes (Received)
    380

    Default

    Quote Originally Posted by Pete Deal View Post
    After reading a lot of posts here on 30 taper machines, including some pm's with BROTHERFRANK, I have fretted a lot over the use of my 2" face mills in my machine. Mostly I have backed off from using them in production because of this risk. If something goes wrong using a cutter this size it is almost guaranteed that the the spindle will be toast. Pushing it hard makes this a whole lot more likely.
    Pete, I would prefer to give my opinion myself. I would run that 2" cutter all day long. I run the 5" OSG Disc Cutter taking .125" doc at 4" width of cut at 150 ipm. I haven't seen a pull stud break on it's own in 24 years of running BT30 machines. Work holding issues, programming, bad offsets, no or improperly aimed coolant ... I've run the Century 2.5" at 16k... If there is any chance you can pull a part out of the work holding, you are taking a risk.

  14. Likes wheelieking71, eaglemike liked this post
  15. #51
    Join Date
    Sep 2007
    Country
    UNITED STATES
    State/Province
    Washington
    Posts
    5,181
    Post Thanks / Like
    Likes (Given)
    188
    Likes (Received)
    1544

    Default

    Quote Originally Posted by wheelieking71 View Post
    In red ^^^ That is 40 taper territory. No way I would try that in my Brother.

    I believe Frank sells both his own studs, and JM Performance studs.
    If you look on Maritool.com @ the BT30 studs, the "high-force" studs come from JM Performance. I am sure Frank will chime in and correct me if I am wrong.
    I run a mix of both. For drilling/tapping/reaming/ or anything that I am sure is a very light load (chamfering with a 1/8" drill/mill) I'll run Franks studs.
    Anything that raises an eyebrow gets a high-force stud.
    Cough, cough ...

    Standard roughing for me is 16k RPM, 1/2" Diamondback, 1.25" deep, .150" stepover, 288 IPM, which is a little more MRR than Mtndew's parameters. Been doing this for long enough to know that this well within the machine's capability. Not saying that you should do this with your Speedio, just pointing out that it is quite feasible. I have made many tons of 6061 chips with these parameters. You REALLY need to have a solid grip on the stock though, dovetails or Talon Grips (or the like). Grabbing 1/4" with steel vise jaws probably won't be enough.

    Mtndew did specify that the operator forgot to turn on the coolant -- that will ruin your day for sure.

    Regards.

    Mike

  16. Likes wheelieking71, Mtndew liked this post
  17. #52
    Join Date
    Jan 2013
    Location
    Gilbert, AZ
    Posts
    5,878
    Post Thanks / Like
    Likes (Given)
    7404
    Likes (Received)
    7467

    Default

    Quote Originally Posted by Finegrain View Post
    Cough, cough ...

    Standard roughing for me is 16k RPM, 1/2" Diamondback, 1.25" deep, .150" stepover, 288 IPM, which is a little more MRR than Mtndew's parameters. Been doing this for long enough to know that this well within the machine's capability. Not saying that you should do this with your Speedio, just pointing out that it is quite feasible. I have made many tons of 6061 chips with these parameters. You REALLY need to have a solid grip on the stock though, dovetails or Talon Grips (or the like). Grabbing 1/4" with steel vise jaws probably won't be enough.

    Mtndew did specify that the operator forgot to turn on the coolant -- that will ruin your day for sure.

    Regards.

    Mike
    I am obviously gun-shy! LOL. I do run the heck out of a 3/8" S-carb though.
    Having said that, one of the tools I mentioned I hate running in there is a 2.5" dia. x .437" 9 tooth woodruff!

  18. #53
    Join Date
    Jun 2015
    Country
    UNITED STATES
    State/Province
    Texas
    Posts
    425
    Post Thanks / Like
    Likes (Given)
    87
    Likes (Received)
    103

    Default

    Quote Originally Posted by Wsurfer View Post
    Yikes,
    Sounds like I need to slow the fk down.
    Maybe, maybe not. Cost of doing business. Brother spindles are reasonably priced compared to ones that cost a Haas mini mill. Just expect you'll need one someday.

    I leave some margin for error because I only have one machine. I'm in awe of how some of these guys push theirs, but I don't have that much cushion. High end SFM on my 1.5 Mitsu face mill is 3k, so I run it at 5500 RPM. 3mm max depth. I run my roughers over rated SFM, but radial don't get much over 10% unless the cut is shallow.

    My money is on pull stud was fine. Part came up and forced the break. No room for error running balls out. Sucks bad.

  19. #54
    Join Date
    Jun 2012
    Location
    Michigan
    Posts
    4,685
    Post Thanks / Like
    Likes (Given)
    4297
    Likes (Received)
    2845

    Default

    Quote Originally Posted by wheelieking71 View Post
    In red ^^^ That is 40 taper territory. No way I would try that in my Brother.
    It's definitely pushing the limits for sure. Stubby holder, dual contact, etc..
    We've slowly crept up to those parameters and found a sweet spot.
    Do I recommend this cut for others? lol no. Besides, the new spindle was "only" $6500 or so.

  20. Likes JonP liked this post
  21. #55
    Join Date
    Jan 2013
    Location
    Gilbert, AZ
    Posts
    5,878
    Post Thanks / Like
    Likes (Given)
    7404
    Likes (Received)
    7467

    Default

    Quote Originally Posted by CosmosK View Post
    My money is on pull stud was fine. Part came up and forced the break. No room for error running balls out. Sucks bad.
    I would kind of lean the same way. Not actually being the guy that loaded the part though, we will never know.

  22. #56
    Join Date
    Jan 2013
    Location
    Gilbert, AZ
    Posts
    5,878
    Post Thanks / Like
    Likes (Given)
    7404
    Likes (Received)
    7467

    Default

    Quote Originally Posted by Mtndew View Post
    It's definitely pushing the limits for sure. Stubby holder, dual contact, etc..
    We've slowly crept up to those parameters and found a sweet spot.
    Do I recommend this cut for others? lol no. Besides, the new spindle was "only" $6500 or so.
    I don't have dual contact. I was talked out of it by the salesman. I was stupid for listening to him.
    At the time, I didn't have the time to do enough research. I regret that.
    Same salesman talked me in to a chip conveyor that I despise! Again, I got my research the hard $$$ way on that one.


    EDIT: I just went back and looked at the pics. One thing I didn't see anybody ask:
    That part is pretty thin. What does the work-holding look like after the crash? Show us pics of the jaws................
    All the focus seems to be on the pull-stud. Sure, everybody wants to quickly point a finger, I get that.
    But, I think this deserves a little deeper investigation.

  23. #57
    Join Date
    Jun 2012
    Location
    Michigan
    Posts
    4,685
    Post Thanks / Like
    Likes (Given)
    4297
    Likes (Received)
    2845

    Default

    Quote Originally Posted by wheelieking71 View Post
    I don't have dual contact. I was talked out of it by the salesman. I was stupid for listening to him.
    They tried to talk us out of the dual contact also. Once you go dual contact, you never go back.

  24. Likes wheelieking71, barbter liked this post
  25. #58
    Join Date
    Apr 2006
    Location
    Austin, TX
    Posts
    1,745
    Post Thanks / Like
    Likes (Given)
    183
    Likes (Received)
    463

    Default

    Quote Originally Posted by fmari --MariTool- View Post
    Mickey_D,

    I spoke to you. I certainly did not just say ya they can break. I asked you about the application and I also mentioned they we sell high strength retention knobs that are much stronger and better suited for large face mills such as what you are using. A 2" cutter at 10,000 rpms is very fast. That application demands a high strength retention knob. Yes I offered to have my heat treater do an analysis. I stand behind all of my products.

    Not sure what else you want me to do? Send you a $10,000 check? It's very interesting how right away I am the guilty party. No possibility it was taking more than .025" deep. No of coarse not. Impossible. Part slipped out. Any chance 10,000 rpms is too fast for a 2" cutter. Any chance an insert broke off from centrifugal force?

    I just calculated 10,000 rpms on that cutter is 5,000 sfpm. Don't you think that would call for a high strength retention knob? I wouldn't call that a conservative application.

    Did you take advantage of our balancing service? That kind of mass at 10,000 rpms can really generate a lot of force. I have seen assemblies like this have a 50-80 gmm imbalance. This should be balanced as a whole assembly. Cheap insurance and will improve tool life and surface finish.
    Frank - I looked at the pull stud page on your website again this morning and nowhere did it say that you need to use your high strength studs with a face mill holder, not even on the BT-30 face mill holder page. If you know they need it put it on your website. Also, what is the difference between the two? Different materials? Different heat treat process? Different tensile strength and toughness? I have bought enough "new and improved" and "extra high strength" products over the years to take descriptions like that with a grain of salt. If you are doing something like making your high strength studs out of say carpenter 158 so they can have a very hard surface for wear resistance and a tough core that fights crack propagation better than through hardened 4140 or the like. Tell the customer what they need to buy and why - just don't have a regular one and a "high strength one" that costs twice as much with no reason why one is better than the other.

    Fact is the pull stud did not keep the holder in the spindle. It did not over power the drawbar spring and pull the tool out, it was the point of failure. If the pull stud had not failed, this would not have happened.
    I am talking to my insurance company and they said to hang on to everything for now because they may want to inspect it, after that I am going to send it to Frank so they and their heat treater can have a look to. Like I said earlier, I have bought stuff from them for years and have been happy with their service and tooling and I am not trying to drag them through the mud - just share my experience.

  26. #59
    Join Date
    Aug 2013
    Location
    Chicago, IL
    Posts
    850
    Post Thanks / Like
    Likes (Given)
    598
    Likes (Received)
    319

    Default

    Quote Originally Posted by Bruce Griffing View Post
    Don't the drive lugs take up most of the torque about the z axis?
    Yeah, you're probably right...

  27. #60
    Join Date
    Sep 2006
    Location
    Abingdon, VA
    Posts
    3,356
    Post Thanks / Like
    Likes (Given)
    4495
    Likes (Received)
    3106

    Default

    I would definitely go with a high-strength pull stud of whatever brand for a 30-taper machine.

    And as far as the ultimate strength goes --- from a machining standpoint, a pull stud that has been finish ground on the neck and related radii and shoulders will be stronger than one that is just finish turned.

    Why?

    Finish turning leaves the spiral "hills and valleys" around the circumference of the part (albeit very small), with the valleys potentially creating a stress riser, especially near a corner or beginning of a radius.

  28. Likes Nerdlinger, wheelieking71, cameraman liked this post

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
  •