Spindle noise - Question to Tormacheers

Well I cannot speak from experience since I do not own one but just hearing the sound, I agree with your initial diagnosis. Have you attempted to turn the spindle by hand with the belt disconnected? Might be able to feel it if the bearings are ground up that bad. The other thought i had was possibly the pulley on the spindle is rubbing somehow? Could it be loose and slipped down to where it contacts something?
 
If you have ever "played" with a Tormach PCNC 1100, can you take a look at this quick video and tell me what you think the problem and solution are? Thanks!

http://youtu.be/gMUcwRWiyXo

Not sure but sounds to me like drivetrain noise. Is it belt or gear driven? Gear driven can be a little noisey, may need to use some grease on them.
 
It is belt driven. Removed the Spindle cartridge and I can feel the spindle is the one making the noises. Some viewers have stated that I need to work on the bearings and add grease. What a job! But oh well, back to the grinder...

Thanks for your input!
 
I have some experience with bearing replacements in the Tormach and have to say while the recording sounds pretty clear, I never encountered the type of sound that yours appears to have with something like a lobe or "high point" hitting something. Mine was simply an overall change in the otherwise "smooth sounding" that was most normal. Some people will laugh at the approach, but if you use the old mechanics trick of putting a flat tipped screwdriver on the column in different locations and the smooth or hopefully "rounded end" in your ear - you can better pinpoint the area where the sounds seem to be coming from. There are two sets of bearings and you may have more issues with the "upper" or the "lower" set - no way to really know too much better. This isn't as simple as just putting grease where it's dry and Tormach has a pretty specific approach to the use of grease in and around the bearings - which I agree with. Having 1 ounce do some good doesn't mean that 16 ounces does anything better! It's all about having it where you need it and then "protecting" it to make it last longer. Read their literature about replacing the bearings and look at the variety of Utube stuff also related to this subject.

I see your location is in the garage - mine was also but suffered a bit more in the winter months because of not having consistent heat. If you want the bearings to last longer, then you can't expect to walk in "cold" - turn on the spindle and start working like mad! You'll do well to use something of a "warm up routine" IF your garage temperatures are on the colder side. I start the spindle (in reverse) and run it at a low rpm (500-1000) for about 5 to 10 minutes, then stop, reverse the direction and put another 5 to 10 minutes on it. That at least gives the internal components a chance to start warming up and if your garage is on the cold side, then the grease within the bearings "settled" and cooled off in whatever levels existed when you ran the spindle previously. The amount of grease is actually pretty slim and you're not going to move it around much, you're just wanting to get it to "circulate and lubricate" as much as can possibly happen when it's retained in a specific area.

Doing the homework up front before you take on the removal of the spindle and bearings is well worth the effort and time. It will all make far more sense once you've gone thru it and when you get into the re-install portion of the work, the re-tightening of the spanner nuts is a key item to pay attention to. The same theory applies - the right torque makes things work as intended, excessive doesn't make anything work better! My vote would probably be a problem with the bearings as there's little else within the column that moves in a way that might make that sound, unless something very small and hard has dropped in or around the inside of the drawbar area but I would think that would be easy as well to chase down if you just pulled the drawbar out and ran the spindle. Good luck, get your digital camera ready along with the new bearings and follow the Tormach instructions and notes! They're established for a good reason, and good luck. Let us know what it turns out to be. Thanks.
 
WOW!!! Thank you for this great info! Much appreciated!

I have already ordered the ball bearings from Tormach because when I inspected the existing ones they looked like they have seen better days. Now, you are right that this machine is in my garage, but that is not where it was for the past 6 years. In fact, where it was and what kind of stresses it was subjected to, I will never know. I just acquired this machine last week and as I was powering it up, noticed the noise. I do appreciate your input towards temperature handling. I never thought of that! My garage has some shielding so it is not ridiculously cold, but it is no 70F either.

Removing the spindle cartridge wasn't too bad. Removing the spindle from the cartridge was a little bit tough, but with the aid of a press it all came out pretty good.

The problem I am seeing will be putting the cartridge back in! For some reason, it is not going in easily. I don't want to force it as I don't want to mess the column. That would be an expensive ticket item if I mess it up. I think I will need to freeze the cartridge and then heat up the column to aid in this procedure. Will worry about that when the time comes, because the first step is to get the ball bearings which I will receive tomorrow.

Am definitely documenting all of this setup on video as I imagine there will be plenty of others going through the same ordeal at some point in time. Was reading on an article Tormach has sold about 4000 PCNC1100. That's a lot of ball bearing replacements in the future!
 
Getting the spindle back in place isn't really that difficult if you let the machine do the work! I use a short stack of plywood on the machine table to get it somewhat "centered" and to have the spindle "top" level with the column "bottom" before starting to push it to the "seated" position. If you're really careful, you can then turn the machine on (I know this is going to spook out some readers but so be it!) and then with the settings for using the hand toggle in a very slow setting - just gradually feed the column down over the spindle. While you're feeding the column down, it's easy to feel the engagement of the outer diameter of the spindle with the inside of the column. If it's not moving in as "smooth as glass" then it should not be going in! (Mine probably has .003 to .005 clearance between the spindle and the column ID - not much more) If you have the pulleys and keyways ready at the top, you can also put them in place while moving the column down which makes it far easier than trying to lift the spindle. It also helps to be a bit "greasy" by having a generous coat of WD-40 on both the spindle outer surface and the column inner surface. If you use oil, grease or something else, you'll be wiping it up for months as it collects around the bottom of the column/spindle flange which is a pain.

Another thing that's a bit too late now but maybe you already considered it is to put a small pin-punch mark on the OD of the column flange and another on the column steel at the same point. IF the previous alignment of your spindle to the table surface was good, this would permit you to put the spindle back with the same axial orientation which can make a difference. In my view this should have been done at the factory when they signed off on having an acceptable alignment but I could not find anything representing that effort. You'll know whether you have any issues when you finish bolting the spindle flange to the column and then use your longest tramming arm to check the alignment in both the X and Y axis. If you want that fly-cutter to be making clean passes, both need to be good. The only way I've ever been able to get mine to that level has been with shims between the spindle flange and the bottom of the column. Take notes that are relative to the (6) bolt positions and you'll end up with an acceptable alignment that you can then repeat if/when you have to pull the spindle again. In my case, I pull it more frequently than normal as I have built a "stand-alone" high speed spindle that gives me rpms in the 25 to 30,000 rpm range and uses a marriage of the Kress spindle and one that "houses" the Kress on the same machine centerline. No offsets or position corrections to worry about and it runs cool for hours at a time when needed. I can change from the standard Tormach spindle to my "high speed" version in about 15 minutes and I'm ready to cut with those .003 to .005 dia. single lip cutters and they hold up surprisingly well when you can take out the opportunities for external vibration with the offset arms that Tormach sells. I use the power cord plugged into the coolant pump circuit to permit me to trigger the unit "on or off" within the code.

Fooling around with the spindle isn't really brain surgery but it probably feels like a dose of "apendicitis" when you haven't done it previously.

Hope your re-install goes well and that you can tell us what you've learned when you're done! Thanks.

Chips4Lips
 
Thanks for all this input Chips4Lips! I have learned so much during the past week as I dismantle this thing and read the responses you and many others have provided. I am very grateful!

During all this ordeal, I did make one lethal mistake which ruined one of the ball bearings, but this is no biggie as I am replacing the bearings anyway. It bugs me that I messed it up, though. I should have known better! I am documenting the mishap, as luckily I was recording the blunder.

What truly worries me is that I have not been able to place the cartridge on the tower cavity. I tried freezing the cartridge to -4 degrees and even then it won't go in. I am not ready to fully assemble this yet, as I need to grease the new bearings, which I will be doing in the upcoming minutes. But when the time comes, I will try to heat the tower with an industrial blower (if that even has a chance of working) and I will freeze the assembly again to see if that helps. I think I will need to pass a screw through the spindle cartridge and build a rustic puller to put it all together, though. I am only hoping this tower is not somehow deformed and the cartridge can't go in easily. I know I am most likely freaking out unnecessarily, but since I have never done anything like this, it is the natural response. I hope to have joined the ranks of experienced spindle'ers in the upcoming days ;-)
 
I had a a spindle bearing go out on my in warranty PCNC770. When running at 10,000 rpm for some time the bearing would scream as the spindle wan down to a stop. Tormach Customer Service was skeptical at first but when I sent a recording of the noise they immediately said "bearing problem" The 770 spindle cartridge must be replaced as a unit although it can be broken down to components. A new replacement was sent and it had serious runout issues. It turned out that when they bored holes in the spindle face to balance it, they had not removed the burrs. An after hours trip to Tormach fixed that problem (fortunately for me, it's only a 40 minute trip).

While I did not have to pull the assembly apart, I did have similar issues with adjusting the spindle nuts for proper torque. Tormach states that there is a change in length of the spindle due to heating so the adjustment for end play is somewhat a compromise. They advise running it after adjustment and checking temperature rise. I made a a socket spanner for the spindle nut and spanner wrench from one of the several extra 22mm wrenches in the TTC kit for the pulley nut.

I have been running the machine for more than a year now with no incident.
 
Regarding installing the spindle, the advice above is good. Use the z axis drive to press it in. For the final push, I used the spindle mounting screws to pull the cartridge home. You can pull it in with a set of screws of appropriate lengths as well. The advantage of this method is that your holes are properly aligned for final; fastening which could be an issue if you have a close fit on the assembly. Good luck with your repair!
 
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