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Bob G
11-05-2009, 09:21 AM
I have a project that requires a pair of self aligning bearings and have not had any success finding a source.
I would prefer ball bearings but I can use Oilite bushings. The bore should be between .1875 & .250. The attached drawing is a rough idea of what I need.

Thanks in advance.
Bob G


http://i219.photobucket.com/albums/cc50/garrett_robertl/BearingSelfAlign.jpg

Duffy
11-05-2009, 09:26 AM
Could you try a supplier of Oilite bushings? I have seen these used in small shaded pole motors, and presumbably the bushing maker also makes the bushing holders. Duffy

Evan
11-05-2009, 09:29 AM
http://www.vxb.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=bearings&Category_Code=Self-aligning

Ken_Shea
11-05-2009, 10:25 AM
Bob,
These are available direct from the mfg.
http://www.igus.com/igubal/sizepresent.asp?p=EFOI

They are made from Hi-Strength plastic.

Forrest Addy
11-05-2009, 11:59 AM
Yup. That's a standard pillow blovk design widely aailable in graduated sized on self aligning ball bearings and also with oilite.

Look in most any power transmission product catalog like Boston Gear. Martin, Dodge, and the usual suspect in industrial supply houses plus your local bearing and motor shops.

You need a very small size. Pillow blocks in this size range are very bulky for the shaft size. Yoy may have to bush them down from a larger size. Oilite bearigs come with a spherical OD but you'll have to make your own mount.

Carld
11-05-2009, 01:13 PM
Bob, those bearings are not hard to find. You may not find the dimensions you want but they are available from almost any bearing supply company. If you require a certain dimension for the housing then you can buy the bearings and make the housing.

EDIT: well they may be hard to find because in ball bearing they only go down to 1/2" shaft so you would have to bush them. It looks like your going to have to use bronze or oilite unless you can find a specialty company. I have seen small flange bearings in business machines.

Fasttrack
11-05-2009, 01:49 PM
Can you handle metric?

http://www.vxb.com/page/bearings/CTGY/Self-aligning

6mm would be about 0.236 inches.

Bob G
11-05-2009, 05:32 PM
My biggest problem is I'm [80] years old and my shop consists of a vise and a hand drill. Twenty years ago I could have made what I need in my own shop.
Kens plastic parts would do the job but what I am working on is a Rotary Stirling Engine and the 176 Deg. F max might be a problem.
I have found both ball & Oilite bearings but none as an assembly ready to mount.
Thanks again,
Have Fun,
Bob G

Ken_Shea
11-05-2009, 05:47 PM
Bob,
As it so happens, the max long term temp is 176 Degrees F
Max Short Term 246 Degrees F
They don't just melt but the load carrying is diminished.

Ken

Evan
11-05-2009, 06:27 PM
For a Stirling engine any sort of friction bearing is out of the question. It is essential to keep friction as low as possible. Rather than use ball or (gasp) a friction bearing is it possible with your design to support at least one end of the shaft in a needle and cup bearing?

Ken_Shea
11-05-2009, 06:47 PM
Evan,
My guess is that Bob was only using the ID as a loose bushing fit that would offer very little resistance.

Could also ream out the ID of the flange bearing and press fit a 5/16OD X 3/16ID needle roller bearing.

Thought I had him all fixed up on that but what i have are .250OD X 1/8 ID needle roller bearings.

andy_b
11-05-2009, 07:58 PM
My biggest problem is I'm [80] years old and my shop consists of a vise and a hand drill.

Thanks again,
Have Fun,
Bob G

where in PA are you? i have access to a really big vise and several hand drills. seriously though, if someone is near you they (or i) might be able to lend a hand for the non-vise and non-hand drill related tasks. :)

andy b.

Ken_Shea
11-11-2009, 10:18 PM
Bob G,
Did you find a solution to your bearing?

Ken