Printable View
Has anyone out there done a spindle repair on this machine? The spindle on my machine is ceased and its most likely bearings. I need to pull the spindle from the PREX motor in order to have a look at the bearings but I am not sure exactly how to do this. Any advice would be greatly appreciated. Please Help! Thanks.
You are in for a big project. The spindle is liquid jacketed for cooling so you will need to drain off the fluid and pull the spindle as a cartridge. It will be messy no matter what. There are large o-rings on either end of the jacketing and they do not want to come out easily. After the cartridge is pulled, the armature and Stator can be separated and the bearings can be replaced. New bearing should be preloaded and run in before reassembly if possible to verify preload. I'd suggest having the whole headstock taken to a reputable spindle repair company that is experienced with this since it is the heart of your accuracy, but if you're daring, it can be done in the field and the bearings can be run in on the machine. The preload is actually checked by temperature to verify so that is why it's better to run it in while off the machine so adjustments can be made if needed.
Best regards,
Hi OkumaWiz
Thank you for your reply. I have been exploring this option while waiting for the the local machine tool distributor to get me the final numbers for what this rebuild will cost. I have found another local machine tool service company that can remove the whole headstock as you suggested. This sounds like the best option to me. I intend to send it to a spindle repair shop in the US. They have stated that they can do all the repair work, bearing, preload, run in etc as you mentioned. This is how I am going to proceed as this type of work is way beyond my expertise. Thank you again for your reply as this gives me confidence that I am proceeding correctly.
On another note: there isn't a lot of information on repairing/servicing these machines on the web, in machining forums etc. I get the impression that these machines are rare, rarely break down or that people just do not want to share this valuable information. What do you think?
hy shooter :) what happened ? what caused the failure ?
... parts for spindle : 7000
... shipping : 500 - 1000
... workmanship : 1500 - 3000
if you are lucky, the bearing inside the hydraulic cilinder are ok, but how it is being spinned by the spindle ( as long as minimal hidraulic pressure exists ), then any motion problem inside the spindle is copied inside the hydraulic cilinder; so, if there where motion shocks, discontinuous rotation, etc, consider also this :
...hydraulic cilinder : 4000
* all these numbers are informative, may be different values in your area
hmmm
aaa, there is a method to lower costs, like finding a service guy which is no longer working at the service provider; for example, if you have conections, maybe you can find such a guy : retired, or no longer working at the service dealer; i know such persons, but not in your area :)
do you proper maintain the machine ? is there spindle oil replacement done regulary, is the oil level checked at least once / week ?
sh**t happensQuote:
What do you think?
i can help with tips about lowering cnc reaction time, lower servo torque limit, 100% process monitoring, and others, that are not 'default'; prevention is the key, and osp has stuff inside it, that allows configuring the machine in ways not possible on other brands / kindly :)
Hi DK
I do not know what caused the failure. There is only 3000 spindle hours on the machine! I have hired a local machine tool service company to remover the headstock. I am going to crate it and ship it to a spindle repair shop in the US. Believe it or not, this will lower my repair costs but it is the machine downtime that really hurts. The OKUMA tech did mention that the hydraulic cylinder is leaking oil so the next step is to look at this part. What I can tell you right now is that the hydraulic cylinder is not ceased. Maybe I should send it to Kitagawa for evaluation and rebuild or is this something a person can do in-house?
Please contact on [email protected]
maybe now is a bit too late for this advices, but :Quote:
I do not know what caused the failure
... from time to time, you may check the alarm history inside mac-man, especially for diff over alarms, and alarm A types
... you may use an application, which is defult with osp300a, that simply takes a photo of the screen each time there is an alarm; like this, you no longer have to check the mac-man to search for an error, but simply check the 'suite' folder, which creates a snapshot each time an error ocurs; and there is also the possibility to send the photo/printsceen, via e-mail, to mobile device, etc
... get used with spindle loads at 2000rpm eq, and spindle temperature, and re-check periodically
... use a ' i don't know how is called' device, that measures vibrations, and put it on the spindle once/week, and observe the long-term progress :)
also, there are the tips from the end of post #4; so far, i have not shared the implementation method, but only described what is possible / kindly :)
Thanks for the tips Deadly Kitten. I have recently learned from a very honest person in Michigan that some of these OKUMA LB lathes have a known front tapered roller bearing issue. Apparently there is a list of machine serial numbers that have these bad bearings but my local machine tool distributor failed to mention this. I am going to dig into this. I will post when I have an update.
if i may, do you still have guarantee on your machine ? or assurance ? are you covered ? kindly :)
Hi DeadlyQuote:
Originally Posted by deadlykitten
No I do not have warranty on this machine anymore. I do not expect OKUMA to cover any costs. At this point I just want to get this machine fixed and back running. It sounds like OKUMA was aware about this bearing issue and covered this type of failure beyond the warranty period (when the customer was informed of the issue, which I suspect was rare) but realistically I am just a small customer to them , why would they care. Its too bad the small customers have to suffer.
our okuma dealer, at least the big-boss, is very gentle and he treats the small customer with same respect as a consacrated customer
whatever the problem, he never refused, but always helped :) he knows how to embrace things ...
about the fact that you know that there is a list of machines with lower quality bearings, play it nice, discuss it with your okuma dealer if you wish, but try not to share things about the person that told you so; on this forums are members ( at least 3.45 ) that work inside okuma, and he may get into trouble; i don't know, i am just saying :)
another tip, about protecting the spindle, is using the " power peak cut " special function
is good to have an assurance, especially one that covers any " accidental damage "; you know, it may be possible to get a replacement bearing as " good " as the faulty one; even if you activate as many safety things as possible, some stuff may still happen / kindly :)
Hi DeadlyQuote:
Originally Posted by deadlykitten
Yes well put. They are people too and I may have jumped to some conclusions but often when there is money involved it can get ugly. Thanks for the tips. The last thing I want to do is get someone in trouble that is trying to help. Anyway I guess I have to let go of my frustration and move on. I will post more as this spindle rebuild progresses.
I have to ask, are you really in Antarctica?
Just an update: the machine headstock is at the spindle repair facility in the US and they informed me that they will be tearing it down soon. Will post again when I know more.
I have see in the past that a drain for the spindle labyrinth seal can get clogged and cause bearing failure. Have you checked by the firewall under the spindle to see if yours has the drain and that is is clean?
Best regards,
Hi Okuma WizQuote:
Originally Posted by OkumaWiz
I had another person mention that too. I am not aware of any drain and the headstock is at a repair facility right now so I cannot verify. There was a know problem with a bearing on certain machines and OKUMA sent out a bulletin to distributors (I was able to read it the other day). Are you aware that they had this issue? You should check out PM forum OKUMA LATHE LB-3000 SPINDLE REPAIR.
Although the drain comes out of the spindle housing, the area that got clogged was built into the firewall and can be seen without the spindle if you have it. If there is nothing but straight firewall with no drain “catcher” built in then your model maybe doesn’t have it.
I was not aware of the bearing issue.