How do you choose a bearing

Rob Keeble

Member
Messages
12,633
Location
GTA Ontario Canada
So i looked up a specific bearing that is common for many of our machines when you get down to the basic part number....in this case 6203.

So this site is recommended all over the web on woodworking searches and it looks like they have a significant variety and this is just the issue that i have come across before.

Take a look at this search

http://www.vxb.com/mm5/merchant.mvc...r&Store_Code=bearings&SearchOffset=0&Offset=0

Hope it comes out way i saw it. Anyway all i did was type in 6203 in the search box and got this 2 page list of options.

Looking at the variations in price one can go from $2.37 all the way in steps thru to $371.77 dont forget the .77 :D

Now i know the basics like the dimensions matching and sealed versus unsealed and different types of seals but let be real at the hobby end of the scale how do you choose

Can anyone offer some insight (obviously the sizes have to match what you after) i read up on a couple of bearing manufacturers sites in the FAQ but they only seem to confuse one even more especially when you get into clearance specs like the C3 versus others and the terms like fit versus clearance.

I can see in some applications for our machines where we would be long gone before the bearing wore out if we purchased specs of no applicability just to be on the safe side.
If i recall correctly this is the same bearing that was on my Delta band saw and i can tell you that was supposed to be "American made" ( yeah right American assembled) with a 5 year warranty being the "X" rated machines and yet with relatively very little use i found that the bearings were shot and upon changing them i could not believe the difference in the noise never any other gain.

I am contemplating changing the bearing on my Busy Bee lathe spindle for similar reasons but at the moment its better the devil i know than what i don't.

In most of our cases these bearings are being placed under overhang weight type loads even if they have a dual bearing configuration on the shaft/arbor. This would add to run out in any rotating shaft being used for turning a cutting tool.

BTW i did find it very easy to change the bearings on my band saw and the installed ones were not even properly sealed from Romania go figure.
 
No real help from me on bearing selection, but I'm curious why you want to change out the spindle bearings on your lathe. Are you hearing a specific noise or seeing other symptoms (like bearing slop)?
 
Not really sure what you are asking exactly Rob... :huh:

Basically I only buy Japanese made bearings the best in the world IMHO, some of the Euro bearings are good too, but for my money, its NTN, Naichi or NSK.

Otherwise it really depends on what the application is, the speed and the environment of the bearing. I would imagine for your bandsaw regular steel shielded ZZ bearings would be fine.
 
Made in China, I'd probably pass.

Made in Germany, Japan, the USA, Canada, or Northern Europe, I'd pick a lower price point and see how long it lasts.

If it burns out, pick a couple of price points higher.
 
Thanks for the input guys. Vaughn since changing out bearings on my bandsaw and experiencing the difference, I have just had it in mind to give my lathe a go and see the difference. My bandsaw experience really conveyed the point that not all bearings are created equal even if they look the same.

Stu my thoughts were exactly what you said...Stick to Japanese.

But check out the range of price for the same bearing.
My question is say one purchased a Japanese unut for i dunno lets just say $10 then $40 and say $150 or even $300. What would the practical difference be.
Would you ever put a ceramic roller bearing into a woodworking machine?
Take a table saw, i bet the bearings on say a sawstop saw arbor versus a table saw of equivalent power at our local Busy Bee tai chi import special are not the same quality if the were the same size and format.

So we have people examining arbor run out etc and perhaps simply upgrading the bearings would make a significant difference is what i am thinking. At the end of the day its a vital part of rotating machines.


Sent from my SGH-I337M using Tapatalk
 
Back in the day when I was teaching, I had a bearing house rep come into class and explain the differences in bearings. Something he said then has stuck with me all these years later. He said bearings were manufactured in few places in the world. The intention to manufacture a bearings to best military spec did not always play out, but the bearings that failed, passed lessor tests, and that there was a market for nearly every bearing manufactured. The cost escalated downward of course. So maybe quality we are unable to either measure or even appreciate plays a big role. Since those days, a much greater manufacturing presence in the Far East may have spawned bearing manufacturers with lesser aspirations of quality. The numbers on a bearing have lots of information built in. Some of it is the level of quality. Beyond that I cannot explain, except for this: The bearings used in that 10 year comet chasing space craft probably ought to be of greater quality than even the Sawstop! Just sayin....:D
 
The shielded bearings from VXB have served me well at a good price. I used them to replace the stock bearings on my larger bandsaw. I bought enough for a few change-outs since the price was right. Its been years and I am still on the first set. Not so sure that worked as I had planned but, I still have plenty of spares :huh:.
 
Last edited:
There are a number of different reasons to look at bearings a bit differently.

First off let me say that American made bearings are sometimes going to be a high quality product. Last year I was at Timken bearing in Lebanon New Hampshire and I will vouch for that manufacturer being a high quality outfit. Almost needed surgical gowns just to tour the place. Bearing manufacturers are about the only manufacturing places that rival the gage makers in tolerances of manufacturing processes.

About bearings ---

We don't always see or think about what bearings are used for, besides our selection.

There are speed requirements and load requirements and life requirements

Some applications have stringent runout requirements.

If I had some REAL need - as I did in designing a hobbing attachment for a Maier Swiss Turning machine - I would call a bearing supplier and have them come in to visit me and discuss the requirements and have them spec out a bearing for me. I would not try to spec it out myself - not in a critical operation.

When I buy machines (not table saws and stuff like that - I buy machines in the 1/2 million dollar range) - I CERTAINLY, am into bearings - on those machines. Sometimes bearings change size as they warm up and that affects the machine performance. Bearings mean a LOT to me.

Imagine a Router with bearings that are under rated on speed requirements.

Some bearings will carry a heavy load.

Some bearings need thrust characteristics.

I can easily see the applications for a $300 bearing vs a $10 bearing.

My estimation for our woodworking is a "decent" low cost "SEALED" bearing, not the chinese ones.
I would not hesitate to buy the American Made Timken bearings - price being the governing factor.
Japanese and German bearings are also great choices.

Except for a router - just about any "decent" - not chinese bearing will serve us well on a hobby woodworking machine.
A router will need certain "speed" characteristics.

Most if not all of our bearings will be single row ball bearings. I would add - sealed, and possibly lubricated.

So, on our woodworking machines - that really boils it down to the major important stuff being -- SIZE.
 
...Vaughn since changing out bearings on my bandsaw and experiencing the difference, I have just had it in mind to give my lathe a go and see the difference. My bandsaw experience really conveyed the point that not all bearings are created equal even if they look the same...

You mentioned that your bandsaw became quieter with new bearings. What part about the bandsaw was quieter? It is the wheels spinning or the roller bearing blade guides? Is your lathe making any appreciable noise? Unless your lathe is whining or squealing, I don't think you'll see a noticeable difference with new bearings, regardless of the price.

Personally, instead of spending the time researching and replacing bearings, I'd spend the time turning some stuff. ;)
 
And Leo, we had three machines at work that were used to turn printing cylinders, some weighing 1500 lbs.with 60" wide faces. these machines had a cutter wheel that had diamond cutters and turned at 3200 rpm and they held tolerences down to 1micron on the finished surface. There were no bearings in the spindle. it was supported by hydraulic pressure, and floated in the spindle housing. They are made in Switzerland, by Daetwyler Company and are pretty amazing.
 
Surgery was mentioned here. I would certainly expect things like ceramic bearings to be used in devices like MRI machines. There are also grades of stainless that are magnetic, verses non magnetic for hospital uses.
Could you find the specs on all those bearings? I'd expect there would be different tempeture ranges for the material. I just bought some bronze bushings, for a pizza oven (helped replace them 3 years ago), and what looked like a standard bronze bushing was used. Bought regular to get them by (trying to keep from needing a hard hat), and tried to find higher tempeture ones locally (rather then pay $40 each, where the regular ones are under $1). Mixed luck (not to the tempeture I would like), and found some graphite impregnated ones, that go over the tempeture I wanted. I plan on putting them in and seeing if it goes longer then three years.
That doesn't even cover if the bearings are certified (in certain specs) or have tighter tolerances, etc.
Would I use ceramic in a woodworking machine? Only if I worked for a bearing place and they were free.
 
You mentioned that your bandsaw became quieter with new bearings. What part about the bandsaw was quieter? It is the wheels spinning or the roller bearing blade guides? Is your lathe making any appreciable noise? Unless your lathe is whining or squealing, I don't think you'll see a noticeable difference with new bearings, regardless of the price.

Personally, instead of spending the time researching and replacing bearings, I'd spend the time turning some stuff. ;)

Very wise advice..
 
And Leo, we had three machines at work that were used to turn printing cylinders, some weighing 1500 lbs.with 60" wide faces. these machines had a cutter wheel that had diamond cutters and turned at 3200 rpm and they held tolerences down to 1micron on the finished surface. There were no bearings in the spindle. it was supported by hydraulic pressure, and floated in the spindle housing. They are made in Switzerland, by Daetwyler Company and are pretty amazing.

Awesome - 4 microns is .00016. That is extremely tight, particularly at 60" wide

The bearings in that were certainly in the very high price range. Even though they are hydraulic they are still bearings. They are called hydrostatic bearings. Some machines also have hydrostatic ways.

We are investigating a process to make master disks at .4 micron or 10 millionths, .0000010 The grinder heads and accurate down to 8 millionths of an inch. Again - bearings are critical.
 
Top