Anyone understand cross slewing bearings?

[Lelandwelds]

A friend of a friend is trying to reform his pack rat ways. His collection of bearings is for sale at essentially scrap price. I have made an offer but the poor guy acts like he is passing a kidney stone.

These are used take offs from a mining operation. Many of them are single row cylindrical rollers. Each roller alternates at 90° from its neighbor. Some have an internal gear ( how do you find a pinion to mate with it?) like out of a crane. The smallest has an ID of about 3 inches. The largest is about 48". The largest weighs about 200 lb.

I have always to build a large positioner. I think I can build a metal shredder or maybe something like a tub grinder. Several of those bearings are large enough to build a car carousel. Many of the roller pieces are large enough to forge into a decent sized knife. ( I have never forged from a bearing!)

I have never knowingly worked with a cross slewed cylindrical roller bearing. They're supposed to withstand high loads from both directions in both vertical and horizontal rotations. They are supposed to take high moment loads too. ( That's pushing down on one side and pushing up directly opposite on the diameter. A twisting motion.)

Can these take a load from any direction all at once?

 

[larry_g]

Are you talking about crossed roller bearings?

http://www.ikont.com/rotary-bearings/crossed-roller-bearings

I've some experience with these, https://www.nbcorporation.com/basics-crossed-roller-bearings/ Way better load carrying than ball type and longer lasting.

lg
no neat sig line

 

[matt_i]

Imo they're nice because of all the line-contact in the cylindrical rollers (as opposed to a single point contact with a ball). And they can be made fairly miniature. SMC has a whole lineup of air cylinder/linear slide actuators (MXS series) which use the crossed rollers in a linear/V-way. Seems like they are also used in first-class machining centers as well.

Not sure how they stack up with tapered roller bearings in a rotary application, typically those are best for impact and high loads.

In any "can I build a...." one has to determine the loads, look in catalogs, etc, to size the components, and figure out how to keep lube in and contamination out.

 

[ilovevocs]

The largest is about 48". The largest weighs about 200 lb.

Pictures please!!!

 

[Lelandwelds]

Are you talking about crossed roller bearings?

http://www.ikont.com/rotary-bearings/crossed-roller-bearings

I've some experience with these, https://www.nbcorporation.com/basics-crossed-roller-bearings/ Way better load carrying than ball type and longer lasting.

lg
no neat sig line

No these these look different. At least one came apart easily. The individual roller is about the same diameter as it's length. There isn't a cage but the plastic looking seal looks like it might double as one. At first glance, it looks like it was assembled incorrectly but each fits in a perfect little pocket.

All my info comes from the seller and some stumbling around on the internet when I got home. Not exactly my favorite position. I have already made an offer. The owner obviously carried these home from some job over the years and doesn't want to over share. He's talking about hauling for scrap but acts like they're cherished family heirlooms.

 

[Lelandwelds]

In any "can I build a...." one has to determine the loads, look in catalogs, etc, to size the components, and figure out how to keep lube in and contamination out.

Where is the fun in that? Nope, I will just wing it if he says yes. My stuff is low volume, low hours and these are comically over sized. I just wish there were two that were identical.

.

Pictures please!!!

I am really bad at picture taking. I just can't seem to remember I always have a camera and phone in the same pocket always.


It s some distance. I don't want to wrangle another visit. He will raise his price or some crazy thing. If he says yes, I will post a project build on sawhorses under a shade tree as my first project thread.

 

[1wook]

Yes the bearings will be able to take high loads from multiple directions at once (axial and radial). What else do you need to know about them?

Slewing bearings are cool, but they aren't used in many designs for multiple reasons. Cost is one of the main reasons. If you can get them cheap enough it might be worth designing your contraption around them. But since it sounds like you don't have two identical ones I wouldn't bother with them. You also will need to figure out how to keep them greased/lubed. Let him keep his cool bearings and don't become a collector of stuff you won't use!

Also bearing steel wouldn't be in my choice of material for forging a knife unless I had large power hammer. Making a cylinder into a knife would be a workout!

 

[Lelandwelds]

Yes the bearings will be able to take high loads from multiple directions at once (axial and radial). What else do you need to know about them?

Slewing bearings are cool, but they aren't used in many designs for multiple reasons. Cost is one of the main reasons. If you can get them cheap enough it might be worth designing your contraption around them. But since it sounds like you don't have two identical ones I wouldn't bother with them. You also will need to figure out how to keep them greased/lubed. Let him keep his cool bearings and don't become a collector of stuff you won't use!

Also bearing steel wouldn't be in my choice of material for forging a knife unless I had large power hammer. Making a cylinder into a knife would be a workout!

This was supposed to happen yesterday but he is declining my calls. He obviously was unhappy about selling his stuff. Oh, well. It's not like I really need a project without a shop to work from.

I sold my second hand tire hammer. I want to build a nicer one myself. I like 52100 for knives. I would like to try a more modern bearing steel.

 

[Slupie]

A friend of a friend is trying to reform his pack rat ways. His collection of bearings is for sale at essentially scrap price. I have made an offer but the poor guy acts like he is passing a kidney stone.

These are used take offs from a mining operation. Many of them are single row cylindrical rollers. Each roller alternates at 90° from its neighbor. Some have an internal gear ( how do you find a pinion to mate with it?) like out of a crane. The smallest has an ID of about 3 inches. The largest is about 48". The largest weighs about 200 lb.

I have always to build a large positioner. I think I can build a metal shredder or maybe something like a tub grinder. Several of those bearings are large enough to build a car carousel. Many of the roller pieces are large enough to forge into a decent sized knife. ( I have never forged from a bearing!)

I have never knowingly worked with a cross slewed cylindrical roller bearing. They're supposed to withstand high loads from both directions in both vertical and horizontal rotations. They are supposed to take high moment loads too. ( That's pushing down on one side and pushing up directly opposite on the diameter. A twisting motion.)

Can these take a load from any direction all at once?

look at Kaydon slewing rings

https://www.kaydonbearings.com/

https://www.kaydonbearings.com/RK_turntable_bearings.htm

 

[Lelandwelds]

look at Kaydon slewing rings

https://www.kaydonbearings.com/

https://www.kaydonbearings.com/RK_turntable_bearings.htm

That is one sweet website. It isn't exactly a 90 second breeze through. I have really only worked with common ball, roller and tapered roller. There is always a next level.

I got excited with the potential for a little bit. My friend says the seller wants to keep his bearings "for later".

 

[larry_g]

So this is what I had pictured when I asked if they were cross roller bearings,

https://www.kaydonbearings.com/XR_turntable_bearings.htm

I had worked with some of these and not heard the name 'slewing bearing' Learning something every day.

lg
no neat sig line