[fastlanecafe]

China has world class manufacturing ability also.

Making a blanket statement suggesting all the bearings they produce are contaminated is ludicrous.

Do you think this company " http://www.nsk.com.cn/ " would stand for that type of business practice?


Jeff...

Jeff-
He did not say ALL bearings were contaminated- he made a comparitave statement. The amount of bearings produced by NSK China and other foreign companies is a tiny percentage of the total. China's bearing production is massive, and in fact, they were nailed for dumping bearings on the US market at below cost. As with most other mass produced Chinese goods, they do have a " fairly high" problem with quality control. If you and Philbur had read the post a bit more carefully, you would see that he was trying to make a constructive suggestion to the Tormach owner on avoiding a repeat of the problem.

[jalessi]

One set of failed bearings out of the entire production of Tormach CNC machines does not deserve a bad rap or a statement like:

"Chinese sealed bearings suffer from fairly high failure due to contamination during assembly. Even if the assembly process is clean, the lubricants they use are often contaminated as well."

The Chinese bearing industry will produce nearly 5 billion sets per year, only a small percentage fail prematurely.

From the very beginning it was stated that the top spindle bearing's where installed incorrectly, not defective product or contaminated lubrication.

The rest of the negative dialog is hyped up drama!

[veteq]

It`s better to say for example

There is a parameter called.

L10 = (C/P)^p

with:
C = dyn. max load
P = Force
p = factor for bearingtype

L10 says that 10% doesn`t perform as the other 90% and has premature faillure

There are also classes called L3 etc.

So there is a standard for less performing bearings, it calculated.


It Would be the same to say, all Americans are the cause off the economic faillure in the states.
It`s better to come with based arguments who has the blame.
Maybe it`s to complex to understand who?
Then dont say anything


If you say something about someone else, you have to come with facts.

[fastlanecafe]

One set of failed bearings out of the entire production of Tormach CNC machines does not deserve a bad rap

Jeff,
The post is about 2 Tormach machines, both with failures- that, according to Veteg's comical formula is 100% failure. Without knowing how many other ureported failures there are, we can only speculate and use generalizations.

[keen]

Keen, what serial number is your machine? This entire thread sounds like my machine has started to sound, I got the squeeks every now and again. Tormach is trying to help me figure it out, but I am thinking bearings at this point.

Hi Bluefin - Just got this - different time zone in NZ. you guys are hot on response!

Yes one pair of my bearings were in upside down . My machine is ser no. 286 04-2007.

If you need to strip down the spindle assembly I have notes from when I did it that may help.

If you fit any make of replacement bearings - contamination ex the factory is not an issue as they come without lube. It is critical the amount of grease - too much will cause overheating - and use the correct grade. The wrong grade could cause overheating, melt out or drop out. I think its worth the expense to use a special spindle grease. EG Kluber isoflex LDS 18 special A

I am trying to remember if there is a way you can see if your bearings are in upside down also - without dismantling the whole assembly. Let me know if that would help and I will study my notes etc.

[veteq]

Jeff,
The post is about 2 Tormach machines, both with failures- that, according to Veteg's comical formula is 100% failure. Without knowing how many other ureported failures there are, we can only speculate and use generalizations.

This a other post of you, mr.fastlanecafe (other thread):

"At least your last post had some information that was useful, which is what these forums are suppossed to be for. Maybe you got a lemon- it happens. Anything made by human beings is subject to mistakes. Its almost weekly news that some big auto maker recalls hundreds of thousands of cars for some defect. Even BMW, who brag about their "ultimate German engineering" had to recall cars for defective brakes. You should have simply sent the machine back for a refund. If not, try to make something positive out the experience by posting your solutions to the various problems for the benefit of others on this forum."

You are a funny man man, MPS.

regards,

Roy.

[LeeWay]

I haven't used Tormach heads or anything else from them, other than tooling holders, but I do see a lot of the same type things using other smaller heads from China. I personally own three of the X2 heads. All three have preformed flawlessly at low temps. Low runout and just decent quality for the price. I have upgraded bearings only in my new lathe and they run the warmest. Highest temp after break in and an hour was 125 F.
I can say that it isn't only the bearings fault nor the head milling. It could be a combo of both. It may also be installation technique and tooling.
Makers of ,machinery can only depend on the rep. of parts. They can surely test machines to an extent, but then after the fact, they ship them. Sometimes these shipments see extreme temps.
I am not saying that any of these things are at fault. Simply mentioning that everything you buy may not be a 1st class product when it arrives. It may require some factory replacements or some user adjustments.
If a fella had paid $50,000, he could expect a man to be there and do this work.
If not, it is just a luck of the draw. Most work without incident, but there are always a few, no matter what you make.
Space Shuttle comes to mind here.

I know it does not feel very well to get a new machine and have trouble. One must consider the outlay however and be realistic as to what type support they can expect. I can say the the Zone is the best source of support for the widest variety of items that I have ever seen.

I am glad it was useful in this case.

[jalessi]

Fastlanecafe,

There is only one post in this thread that details a bearing installation problem and subsequent failure.

Why are you attempting to cloud the issue with negativity?

Are you holding a grudge against Tormac?

The overwhelming majority of Tormac posts are very positive.

Sending replacement warranty parts half way around the world in six days is very good service.

You cant change the fact that they are providing excellent service.

On top of that the new Chinese bearings are performing flawlessly as Keen stated in his prior post.

Are you going to find a way to rebut that also?

Jeff...

[philbur]

Keen surely if the top bearing set is upside down it will be impossible to apply any preload. Thefore you should be able to detect axial float in the spindle.

Just a thought
Phil

I am trying to remember if there is a way you can see if your bearings are in upside down also - without dismantling the whole assembly. Let me know if that would help and I will study my notes etc.

[keen]

Hi Phil - You allways show deeper thought than many ! Whats your background?

Anyway your question. The angular contact ball bearings have a small portion of outer race on the non thrust side - just beyond the centreline. I anticipate your next question. "how then can it be assembled? It is not a after assembly cage spreading situation, but simply a press fit over that small lip - maybe only a few thou. Once the bearing is installed it can no longer flex enough to allow disassembly. If the top bearings are in upside down that small land is what takes the weight of the spindle . Scary - and soon squawky !

[seanreit]

..

[fastlanecafe]

Fastlanecafe,

There is only one post in this thread that details a bearing installation problem and subsequent failure.

Why are you attempting to cloud the issue with negativity?

Are you holding a grudge against Tormac?

The overwhelming majority of Tormac posts are very positive.

Sending replacement warranty parts half way around the world in six days is very good service.

You cant change the fact that they are providing excellent service.

On top of that the new Chinese bearings are performing flawlessly as Keen stated in his prior post.

Are you going to find a way to rebut that also?

Jeff...

Jeff,
If you read the thread from the beginning slowly without reacting like Barney Fife, you will see that the original failure was on " Keen's" machine- then " Digits" had concerns about his spindle from which there were no further posts, followed by "Blu Fin " who has the same symptoms as "Keen". You might also note that I did not make any comment, except to defend " Sharpshooter" who simply suggested it might be safer to buy better quality bearings than take a chance on a second set of originals.

[jalessi]

Fastlanecafe,

Digit has a brand new spindle that is not even installed in a machine yet and has not mentioned anything about a bearing failure.

Bluefin has not determined if he has a bearing problem or not.

What is your point?

Now you are attempting to cloud the issue with a 1960's television show.

The quality or service provided by Tormac has absolutely nothing to do with Barny Fife or The Andy Griffith Show.

Talking about a Soap Opera, are you Rabble Rousing for a reason?

Jeff...

[fastlanecafe]

are you Rabble Rousing ?

Jeff...

You are the only one getting roused- is that rabble rousing?

[BlueFin]

Hi Bluefin - Just got this - different time zone in NZ. you guys are hot on response!

Yes one pair of my bearings were in upside down . My machine is ser no. 286 04-2007.

If you need to strip down the spindle assembly I have notes from when I did it that may help.

If you fit any make of replacement bearings - contamination ex the factory is not an issue as they come without lube. It is critical the amount of grease - too much will cause overheating - and use the correct grade. The wrong grade could cause overheating, melt out or drop out. I think its worth the expense to use a special spindle grease. EG Kluber isoflex LDS 18 special A

I am trying to remember if there is a way you can see if your bearings are in upside down also - without dismantling the whole assembly. Let me know if that would help and I will study my notes etc.

Thanks for the information Keen, I have been keeping a watch on the spindle and it has not made any noise in the last week, I still need to talk more with Tormach but I am pretty sure the sound is coming from the spindle and not the drive system. At least I see that the bearings are available on the Tormach website and not too terribly expensive if the thing craps out a year from now or something.

Do the bearings require a press to get them out/off?

[keen]

Thanks for the information Keen, I have been keeping a watch on the spindle and it has not made any noise in the last week, I still need to talk more with Tormach but I am pretty sure the sound is coming from the spindle and not the drive system. At least I see that the bearings are available on the Tormach website and not too terribly expensive if the thing craps out a year from now or something.

Do the bearings require a press to get them out/off?

hi BlueFin - the bearings are not a heavy press fit but a light press of some kind is safer than tapping them in. I attach below a couple of pics of assembly using a press - and a mill quill as a press.

[NC Cams]

RE post 30

YOU NEVER< NEVER< NEVER PRESS AN AC back together!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.

You heat the outer ring, chill the inner and balls and they literally DROP together.

Press them together and you might as well throw them away.

YOU will pretty much ALWAYS brinnell each of the balls as well s the raceway you manhandled the balls over.

The alleged misassembly of the bearings may NOT have been the fault of Tormach. THere are or should be chevrons ( < or >) machined or etched across the OD of the outer rings.

YOu did record the position of the chevron, didn't you? probably not.

If there was no chevron, and someone simply put in generic ac/s, generic AC's will not achieve a preload unless they are of the SUL, SUM or SUH variety

YOu did take photo of them to send to tormach to prove they are/were installed backwards? Probably not.

If the chevrons were >> and wrong, they were mismarked. IF they were <> or ><, they were misinstalled. It is easy to misinstall bearings, BTDT myself. BUT, they are so sloppy it is like a saddle on a sow. I"d find it hard to believe that an experienced assembler would make that bad of a mistake - besides, if the OEM even ran the thing for 5 min, the should have heard it right away.

THings like that happen right away, not after an appreciable period of use.

Point is, one can't really blame tormach for anything if one simply knocks a set of bearings out, especially a machine tool bearing, and starts pointing fingers and waving hands on a website. Any time one points fingers, there are 3 pointing back at you.

Kluber grease is fine but pricey and not necessarily any better than Andok C over the long haul. Bridgeport used Andok C in all their milling machines and some of them ran for 20 plus years with the same Andok C grease.

Bearings get the blame for a lot when actually people cause most bearing problems.

BTW, Bob Warfield has a link on his website (www.delicious.com, I think) that has a bunch of posts listed for spindle bearing service recommendations. They are Bridgeport specific but the same applies to pretty much any machine tool spindle.

My $0.05 offered as former machine tool bearing engineer.

[veteq]

Bearings get the blame for a lot when actually people cause most bearing problems.

Do you mean something like,
Forces that are to high, no proper run-in, no proper heating up?
colisions?

Wrong feed/speeds?

regards,

Roy B.

[NC Cams]

For starters, YES

[LeeWay]

I understand that bearings can be installed by heating and cooling proper surfaces, but you should be able to install bearings using the proper tools without any heat or cold.
If you are always pushing or pulling on the surface that you are seating, there is no pressure on the balls at all.

I noticed that the kit for swapping bearings in the X2 heads from LMS is missing one small part to be able to do this correctly. Otherwise it is a nice dedicated kit.

Where you have to be careful is when bottoming out. You have to sneak up on the seat. Too far and then you have put pressure on the balls and races.

I have swapped out these a few times now. It took a time or two to get the routine down just right, but it does work with the right tools.