Bearing education 101

eligius1427 - Wednesday, June 4, 2008 - 6:30pm

Hi all, been looking for thrust or full complement roller bearings for my wind vane direction arrow for two days now, but have only found plain steel as an option for the most part. I found one company that will make one out of stainless (for $1100 ouch) and another that I'm waiting to hear back from(kaydon), but not much luck other wise. I've checked mcmaster, msc, and google. It has to fit around a 2" OD tube and will be exposed to the elements. Should I be worried about rusting? If i build a shell around it will that protect if from rusting? Can I or should I take one apart and have it painted? I've found bearings in ceramic, bronze, brass, or stainless but none of them are big enough. Ideally a stainless steel needle thrust bearing is what I want. Any suggestions.

Jake

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Why not just use

Rich Waugh - Wednesday, June 4, 2008 - 8:50pm

Why not just use impregnated, sintered bronze (Oilite)?

Rust would probably be an isue with a steel bearing, unless it is heavily greased and sealed. If you can find a sealed bearing that will fit, that may work okay for many years. One thought that occurs to me is to look into wheel bearings for marine trailers. They may have something that is highly corrosion resistant for salt-water use.

I do think that an OIlite bearing would probably work fine for several decades and not need lubrication or maintenance. I've seen old machinery that was out in the weather for twenty years or more with Oilite bearings that were still as good as new. Your vane isn't going to have high rotational speeds so I'm not at all sure that you have any need for needle bearings.

I'm surely no engineer though. Ries Niemi might be able to offer some good advice on this topic. If Ries says it, you can prettymuch take it to the bank, as long as it isn't concerning music (I mean hey, the guy admits to listening to punk rock in his shop!) GRIN

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Thank you very much, rich.

eligius1427 - Wednesday, June 4, 2008 - 9:49pm

Thank you very much, rich. I found a lot of options with the sintered bronze thrust bearings and they are so much more economical. I found a sleeve bearing as well that fit in the tolerances, but the material was called "Rulon" bronze. Any idea what this is? I'll probably ask them in an email, but I'd rather look like an idiot amongst friends. :) Found a bunch of sintered bronze sleeves, but they are too thick, can I flapper disc these down? Obviously this won't be very precise, but since it's just a windvane i thought it might be ok.

Since it's not about music, I'll try to bounce this off Ries as well.

Jake

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Never done it

warren - Wednesday, June 4, 2008 - 10:49pm

Jake,
I think you are making a wise choice to go with a bronze type set up for your bushings and thrust washers. They will last forever. Any kind of bearing will have to have a lubricant. As method before lubricants actual add resistance to the rotation. If you wanted to use any lube maybe some Teflon spray.
I never have made a windmill but I have seen few with the bronze. Now bearings I also know all of the different kinds from being a service engineer.

warren
http://www.metalrecipes.com

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Bearings

Chucky Boy - Wednesday, June 4, 2008 - 11:22pm

Jake,
Currently the world is facing a bearing shortage. Like the Steel prices bearings are becoming more expensive as well as hard to find.
I'm a machinist and it is having a huge impact on the Aerospace Business now.
Anyway, use a sealed Ball Bearing stay away from the needle type. They are far to expensive and do not do well in the eliments. The best you could get for your application would be a carbon/ceramic style (very expensive and an overkill) No lubrication required and can take freaky temps.
Oilite should work but will require lube if temps take a dip. I would recommend a sealed bearing, Marine application if possible. If size becomes an issue have your machining buddy fabricate a reducer sleeve(s) for your 2" pipe and conceal the Assy. If you need further Info. you can find it thru the Machinery's Handbook kind of the Bible for what I do. I did try and find the bronze you mentioned with an application to a bearing with no success.
You'll make it work I've seen your stuff posted this is a peice of cake.
Hope this helps.
Chuck

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Vane Bearing

Nic East - Thursday, June 5, 2008 - 8:29am

Geez, you guys think up some complicated ways to do what a single bearing-steel ball would do, and has done for centuries. I improved on that slightly by using two appropriately-sized bearing balls stacked under the sleeved post of the vane. Add some lithium grease and voila!

Nic East, Jim Thorpe, PA USA Creativity begins with a novel thought.

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I like the simplicity, but

eligius1427 - Thursday, June 5, 2008 - 9:35am

I like the simplicity, but I'm not sure it work for this application or I'm just not understanding it correctly. The direction arrow has a sleeve that sits around the main vertical pipe and rests on a fixed collar. I'm trying to reduce friction between the bottom face of the sleeve and the to face of the collar. If I'm reading this right your method would help the main vertical tube spin, right? If not, could you please clarify further?

Jake

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That's the way I usually do

Rich Waugh - Thursday, June 5, 2008 - 11:18am

That's the way I usually do it too, Nic. One hardened bearing ball that the pivoting tube drops over and rests on in a detent. Elegantly simple and damn near foolproof. However, on Jake's design, it appears to me that there isn't a way to make that pivot method work and that he needs a sleeve and thrust washer type bearing. Therefore, I suggested the Oilite bronze since it needs no lubrication othr than one drop of insturment oil and will last forever in a weathervane. If he can do the single-ball bearing thing, then naturally I would recommend that.

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