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View Full Version : OT: Table saw bearing id different from what it's number says it should be.



Dave C
11-01-2016, 11:46 AM
I bought an old Craftsman table saw with the knowledge that it was going to be a lot of work to restore. The motor runs, but the arbor bearings were growling, so the first order of business was a complete tear down to find out what kind of bearings were in it. This is what is stamped on the bearings: WTW Japan 6202 5/8 RS. The bearing measures OD=35mm. ID= 15.87mm, W= 11mm. Now, my problem is, the specs for a 6202 bearing has the ID at an even 15mm. I've measured the bearing and the arbor a half dozen times, and the ID is definitely .6250" which is 15.87 mm. The OD, and width correspond with the specs for a 6202 bearing. I'm stumped. Did the specs change over the years?

ecortech
11-01-2016, 12:00 PM
The original is a special 6202 5/8 RS indicates a 6202 with 5/8" bore.
Should be available from most bearing suppliers.

Ed

Dave C
11-01-2016, 12:11 PM
The original is a special 6202 5/8 RS indicates a 6202 with 5/8" bore.
Should be available from most bearing suppliers.

Ed

Thanks Ed. Sounds like the price just went up.

JoeLee
11-01-2016, 12:12 PM
That 6202 RS bearing with a 15mm ID is also available in 16MM 6202 RS 16 I think would be the number. I ran into this years ago.
And yes a lot of bearing mfg. have changed their numbering systems as one mfg. buys out the other, it gets confusing.

15.87 is considered 16mm at .624803

JL..............

https://bearingsdirect.com/odd-size-bearings/4029-6202-2rs-16mm-sealed-special-size-ball-bearing-id-16-x-od-35-x-11-mm-sealed.html?gclid=CKrSu8n5h9ACFUlehgodp5wJnQ

Highpower
11-01-2016, 12:24 PM
Thanks Ed. Sounds like the price just went up.


Not too bad really. Amazon (https://www.amazon.com/Sealed-Bearing-6202-10-2RS-Bearings-VXB/dp/B002BBKJGQ/ref=sr_1_1?ie=UTF8&qid=1478017322&sr=8-1&keywords=6202-5%2F8-2rs) has them. Definitely NOT 16mm.

Illinoyance
11-01-2016, 12:25 PM
Had a similar issue with spindle bearings for a Walker Turner wood lathe. They also used a non standard bore. I did manage to find a source of bearings. Was $100 for a pair of bearings.

Dave C
11-01-2016, 12:28 PM
Thanks guys, got lucky and found them on fleabay. Lot of 2 for $4.59 with free shipping. http://www.ebay.com/itm/130820405197
Never would have guessed that they would mix metric and inch dims on the same part. Go figure.

LKeithR
11-01-2016, 01:24 PM
...The original is a special 6202 5/8 RS indicates a 6202 with 5/8" bore.
Should be available from most bearing suppliers...

Yes, in the smaller sizes there's a whole range of bearings with metric OD and width but with imperial bores. Designed to accommodate inch dimensioned shafting.


That 6202 RS bearing with a 15mm ID is also available in 16MM 6202 RS 16 I think would be the number...

Not likely, in the bearing world 16mm is a very uncommon bore size.


...And yes a lot of bearing mfg. have changed their numbering systems as one mfg. buys out the other, it gets confusing...

Primary identification no.s have not changed in decades--a 6202 is 6202 is a 6202. What does change is the suffix no.s which denote seal type, clearances and corner radii among other things.


...15.87 is considered 16mm at .624803...

Not the case. As I pointed out above 16mm is an almost impossible to find bore dimension. A 6202 special will have metric OD and width dimensions with a true 5/8" bore (plus clearance to fit a standard inch dim. shaft). A true 16mm bore would be almost .005" too large for a 5/8" shaft...

Dave C
11-01-2016, 02:08 PM
The bearing number is 6202 5/8 RS. Clearly states a 5/8" bore, not 16mm.

JoeLee
11-01-2016, 03:23 PM
Yes, in the smaller sizes there's a whole range of bearings with metric OD and width but with imperial bores. Designed to accommodate inch dimensioned shafting.



Not likely, in the bearing world 16mm is a very uncommon bore size.



Primary identification no.s have not changed in decades--a 6202 is 6202 is a 6202. What does change is the suffix no.s which denote seal type, clearances and corner radii among other things.



Not the case. As I pointed out above 16mm is an almost impossible to find bore dimension. A 6202 special will have metric OD and width dimensions with a true 5/8" bore (plus clearance to fit a standard inch dim. shaft). A true 16mm bore would be almost .005" too large for a 5/8" shaft... No it's not, it's actually quite common.

JL..................

http://i911.photobucket.com/albums/ac317/JoeLee09/General%20Bearing%206202%202RS%2016mm/Image001_zpsxf0dlslx.jpg (http://s911.photobucket.com/user/JoeLee09/media/General%20Bearing%206202%202RS%2016mm/Image001_zpsxf0dlslx.jpg.html)
http://i911.photobucket.com/albums/ac317/JoeLee09/General%20Bearing%206202%202RS%2016mm/Image002_zps7y6jw1sm.jpg (http://s911.photobucket.com/user/JoeLee09/media/General%20Bearing%206202%202RS%2016mm/Image002_zps7y6jw1sm.jpg.html)

Doozer
11-01-2016, 03:53 PM
I have a Honda motorcycle that I wanted to replace the steering neck bearings.
They were originally loose ball type, but I wanted tapered rollers.
The bearings were a half millimeter size, like 38.5mm x 17.5mm or something
like that. I found a company All Balls Racing that has conversion bearings in
half millimeter sizes, just for what I was doing, converting my Honda to more
modern and robust bearings. It might surprise you what is out there.


--Doozer

Tundra Twin Track
11-01-2016, 10:05 PM
I had picked up a couple 1-15/16" bearing from a bearing supplier a number of years ago,when I went to install them one was a 2" bore but had the 1-15/16 part # stamped in the race.When I returned it the fellow said in 25yrs selling bearing that was a first!

wierdscience
11-01-2016, 10:55 PM
I bought an old Craftsman table saw with the knowledge that it was going to be a lot of work to restore. The motor runs, but the arbor bearings were growling, so the first order of business was a complete tear down to find out what kind of bearings were in it. This is what is stamped on the bearings: WTW Japan 6202 5/8 RS. The bearing measures OD=35mm. ID= 15.87mm, W= 11mm. Now, my problem is, the specs for a 6202 bearing has the ID at an even 15mm. I've measured the bearing and the arbor a half dozen times, and the ID is definitely .6250" which is 15.87 mm. The OD, and width correspond with the specs for a 6202 bearing. I'm stumped. Did the specs change over the years?

Cross over bearings are quite common,at least with yours they had the decency to mark the bearing as a 6202 which definitely makes it a 35mm (1.3779") OD. There is also an inch dimension 1623 that is .625" bore,.437" wide and 1.375" OD,see the issue?Hard to tell apart without a mic.

Some other popular sizes-
6201 x 1/2"
6203 x 1/2
-3/4
-7/8
-1"
6204 x 3/4
-7/8
6205 x 1"

These are actually handy sizes for building things and repair work.I keep them all in stock at work.As an example,small pump motor comes in with a 6203 (17mm .669") bearing spun on the shaft.No time to build up and re-machine and the keyed section of shaft is 5/8" any way,so machine to .6255",grab a 6203-5/8" and put it back in service 30 minutes flat.

wierdscience
11-01-2016, 11:03 PM
I also would mention that OEM's can have bearing companies make any odd combination they want and they can use any nomenclature they want as well.
Never assume the numbers on a bearing are correctly describing the bearing you have in hand.A quick glance at a bearing chart and a caliber to confirm what you have can save you some headaches especially if you have to order something in.

LKeithR
11-01-2016, 11:37 PM
No it's not, it's actually quite common...

Oh you can find them all right, but they're not a common size. At the moment I have three different bearing catalogues on my shelves; FAG, SKF and NSK....not one of them shows a 16mm bore for any bearing...

Lew Hartswick
11-02-2016, 08:44 AM
Never would have guessed that they would mix metric and inch dims on the same part. Go figure.
I have a can full of hardware that is UNC with Metric heads. So why not . :-)
...lew...

CCWKen
11-02-2016, 09:27 AM
Thanks guys, got lucky and found them on fleabay. Lot of 2 for $4.59 with free shipping. http://www.ebay.com/itm/130820405197
Never would have guessed that they would mix metric and inch dims on the same part. Go figure.

"They" have been doing that for many years. Ford used a metric OD bearing with a 1/2" bore in the starters and generators beginning in 1919 for at least the rest of the Model T era (through 1927).

Arcane
11-02-2016, 09:44 AM
Oh you can find them all right, but they're not a common size. At the moment I have three different bearing catalogues on my shelves; FAG, SKF and NSK....not one of them shows a 16mm bore for any bearing...

As I was walking past the assorted bearings in the local Peavey Mart store yesterday, I glanced over and saw 35mm x 11mm x 16mm bearings right next to the 35mm x 11 mm x .625 inch bearings.

Ohio Mike
11-02-2016, 04:51 PM
Typical inch bore metric bearing. Nothing "special order" about it. Any bearing supplier should have it on the shelf or have in a day.

Highpower
11-03-2016, 08:40 AM
Thanks guys, got lucky and found them on fleabay. Lot of 2 for $4.59 with free shipping. http://www.ebay.com/itm/130820405197


Let us know how the surface finish is on those bearings. Chances are the sides will look like they are fresh off the bandsaw. There are inexpensive Chinese made bearings, and then there are CHEAP Chinese made bearings.....

Puckdropper
11-03-2016, 10:19 AM
I have a can full of hardware that is UNC with Metric heads. So why not . :-)
...lew...

They heads are metric, too, they're just not whole numbers! lol