bearing sizes

[wa2crk]

Anyone know the correct size for the jointer bearings? Bearing numbers??
Bill V

[dusty]

Anyone know the correct size for the jointer bearings? Bearing numbers??
Bill V

I believe you are looking for R8-2Z and it measures 12.7mmx28.575mmx7.938mm and is shielded both sides.

Jointer Cutterhead Bearing 001.jpg (1.75 MiB) Viewed 7826 times

Jointer Cutterhead Bearing 002.jpg (775.13 KiB) Viewed 7826 times

The bearing shown is from China, don't know manufacturer but it is marked R8Z.

http://www.vxb.com/R8-2Z-Dia-12-7mm-OD- ... AqlL8P8HAQ

PS It is also marked with the manufacturers code GBC.

http://www.generalbearing.com/products.html

http://catalog.generalbearing.com/db/se ... nch_series

[wa2crk]

Thanks Dusty
Bill

[JPG]

1 1/8 x 1/2 x 5/16

[dusty]

[quote="JPG"]1 1/8 x 1/2 x 5/16[/quote

I don't know what the difference is.

http://www.vxb.com/R8ZZ-Shielded-Bearin ... As1F8P8HAQ

vs

http://www.vxb.com/R8-2Z-Dia-12-7mm-OD- ... AqlL8P8HAQ

If they are form, fit, function equivalents, I would not expect VXB to list both numbers. The later is what is in my jointer. The image is of one that I replaced.

[JPG]

1 1/8 x 1/2 x 5/16[/quote

I don't know what the difference is.

http://www.vxb.com/R8ZZ-Shielded-Bearin ... As1F8P8HAQ

vs

http://www.vxb.com/R8-2Z-Dia-12-7mm-OD- ... AqlL8P8HAQ

If they are form, fit, function equivalents, I would not expect VXB to list both numbers. The later is what is in my jointer. The image is of one that I replaced.

I guess it is to appease those who insist on using mm.

Any time you see strange mm dimensions it is most like a 'inch' dimension.

28.575mm = 1.125"
12.7 mm = .500"
7.938mm = .3125"(5/16)

[jsburger]

1 1/8 x 1/2 x 5/16[/quote

I don't know what the difference is.

http://www.vxb.com/R8ZZ-Shielded-Bearin ... As1F8P8HAQ

vs

http://www.vxb.com/R8-2Z-Dia-12-7mm-OD- ... AqlL8P8HAQ

If they are form, fit, function equivalents, I would not expect VXB to list both numbers. The later is what is in my jointer. The image is of one that I replaced.

I guess it is to appease those who insist on using mm.

Any time you see strange mm dimensions it is most like a 'inch' dimension.

28.575mm = 1.125"
12.7 mm = .500"
7.938mm = .3125"(5/16)

It could also be some difference in parameters other than size. They do have two different numbers. You have to have the correct chart to interpret the number since different manufacturers use different numbering systems. As we know each digit in the number has a specific meaning (bearing type, bearing size, material, number of shields, type of shield, grease, etc.). Also the digit position in the number is relevant.

Here is one example.

http://www.skf.com/binary/79-66347/457013.pdf

Look starting at page 2 of the catalog (page 4 in the PDF reader).