Thrust Bearings vs Bronze Washers

Tachead7075 said:
If that's what you want to call me:). I will take your advice, you seem to be a bit grumpy and looking for conflict. I am just hear for some good conversation about knives and to learn, I'm not looking to argue. Good day to you sir:thumbup:
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Arguing doesn't have to take form in hostility, it's simply a disagreement. Google "argue".

The point is, Mete is well respected and knows what he is talking about. When people talk, listen. You might learn something;)
 
Blues Bender said:
Arguing doesn't have to take form in hostility, it's simply a disagreement. Google "argue".

The point is, Mete is well respected and knows what he is talking about. When people talk, listen. You might learn something;)
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Just because you are respected doesnt mean your always right(talking generally, not about mete). Nor does it mean that everyone should take what anyone says as gospel. I think you may need to take your own advice here man. Are you Mete's personal internet forum defender? Why dont you let him question/debate what I said if he wants to. You started this "disagreement" or "argument" or "debate"(whatever you wan to call it) because I disagreed(really just clarified what he said imo) with Mete but, you dont seem to even care about the topic we are debating. If you dont have anything to say about the topic of this thread then why clutter it up and/or derail it? Let the man speak for himself about the topic of this thread please.

The bearings used in these knives are thrust bearings by design imo. I bet if you had ZT send you a set in their original box it would say thrust bearings on it. Just because they are not being used in a thrust application doesnt mean they are not thrust bearings.

Anyway, all of this really has nothing to do with the original question which has already been answered.
 
Tachead7075 said:
The bearings used in most knives like ZT's are thrust bearings by design even if not being used in a "thrust" application. And, they consist on ball bearings in a bearing cage/retainer so, they are indeed a form of ball bearings.
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To split hairs in this stupid discussion, They are used in a thrust application.
The bearings resist 'preload' forces of the pieces each side of the blades piviot.
Then when the blade is extended & twisting forces applied to the extended blade, this adds greatly to the thrust forces upon the bearings.
As far as rotational forces, I say depending on the pivotshaft to blade and bearing race(groove) tolerences if the bearings carry any of the rotational load.

Personally I think blade rotating directly on a shaft & plainbearings to resist thrust are plenty adequate, Its a freaking knife afterall.
Then again, I would never want to own or build a Rolex watch either.
 
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To clear a couple things up.
*Bearings have balls or rollers to roll on, bushing does not (aka: washer)
*Thrust bearing/bushing is the proper term. They see an axial load ("parallel to the shaft") when you tighten the pivot screw to take out blade play.
*"Thrust bearing" is not a marketing name. They were used on the propellers of ships in WW2 and I'm sure the name was coined well before that.
*Caged bearing refers to the cage that holds the balls or rollers in place. An open, without a cage, bearing the balls would fall out when you took your knife apart.
 
After reading your first msg. So if you do not want to open the knife up, if you have good eyes, or find someone who does (not me). Take a light and look into the pivot screw inside the knife. If it has bearings, you should easily be able to see the little "BB's" separating the blade and handle. That is the best way I can think of, short of opening her up.
 
Deiphod said:
Dumb question, but I'm new to all this, so please forgive me.

Is "thrust bearings" just a fancy marketing name for phosphor bronzer washers, or is there an actual difference between the two?

I could open my knife up to find out, but that would void the warranty.

Thanks in advance.
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What knife do you have?
 
A washer is a bearing, a plain bearing. The others are roller bearings & ball bearings.

I can see how thrust bearing is the correct term. They take the force produced by tightening the pivot. I never viewed them that way, thanks for the education.
 
Taken from Wiki:

A plain bearing (in railroading sometimes called a solid bearing) is the simplest type of bearing, comprising just a bearing surface and no rolling elements. Therefore the journal (i.e., the part of the shaft in contact with the bearing) slides over the bearing surface. The simplest example of a plain bearing is a shaft rotating in a hole. A simple linear bearing can be a pair of flat surfaces designed to allow motion; e.g., a drawer and the slides it rests on[1] or the ways on the bed of a lathe.
 
*"Plain bearing" is a bit of an obsolete term. Go to the Mc Master Carr sight and see what pops up when you search it.
*A linear guide can be either bushing or ball. Most manual lathes have bushings they call "ways". New CNC machines use linear bearings, they call those "linear bearings". :)
 
Navin_R_Johnson said:
*"Plain bearing" is a bit of an obsolete term. Go to the Mc Master Carr sight and see what pops up when you search it.
*A linear guide can be either bushing or ball. Most manual lathes have bushings they call "ways". New CNC machines use linear bearings, they call those "linear bearings". :)
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Thank you, Navin, that was educational. They divide thrust bearings into two groups: thrust washers; & ball & roller thrust bearings . http://www.mcmaster.com/#Bearings

So in summary, it seems all these types used in knives are thrust bearings. The distinguishing groups are thrust washers, thrust roller bearings, & thrust ball bearings.
Getting back to the OP's question, the term Thrust Bearing doesn't distinguish, it is the all encompassing general term.
 
Now that all that's covered... how about telling us what knife it is and I'm sure someone can tell you what the hell is actually in that pivot assembly of yours. Lol.
 
mete said:
Thrust bearings can be ball or roller.IIRC the rollers of big thrust bearings can weigh 5 pounds !! => for your BIG knives !!
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I got a friend working as the financial manager of a "small" company which all it does is make bearings. The biggest ones they make are meant for those huge cranes you see in the harbors meant to load and unload containers and different goodies from the cargo ships. He knows nothing about the process of making them, but once in a while he gets down to the factory itself and takes some pictures for us... Trust me, the rollers on those bearings are MUCH HEAVIER than 5 pounds... XD XD

Quite interesting all the science that goes behind the design of any bearing. And much more interesting is knowing the cost of the production VS the regular sales price.... they are soooo cheap to manufacture!
 
Tachead7075 said:
The bearings used in most knives like ZT's are thrust bearings by design even if not being used in a "thrust" application. And, they consist on ball bearings in a bearing cage/retainer so, they are indeed a form of ball bearings.
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They are being used in a thrust application, though, most of the force on the bearings comes from the pivot squeezing them and not from the blade moving, hence they are being used in a thrust application. Also, the 'ball bearings' you reference are not the only bearings being used out there, and are still considered 'thrust bearings' that are just not designed for heavy loads (making them fine for small loads like pivots of knives).

You might be misunderstanding what you're reading online.
 
KingMC said:
They are being used in a thrust application, though, most of the force on the bearings comes from the pivot squeezing them and not from the blade moving, hence they are being used in a thrust application. Also, the 'ball bearings' you reference are not the only bearings being used out there, and are still considered 'thrust bearings' that are just not designed for heavy loads (making them fine for small loads like pivots of knives).

You might be misunderstanding what you're reading online.
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While they are definitely under some thrust force, I dont consider this to be a true thrust application myself although these are thrust bearings. A standard bearing, like used in some other brands folders, could have worked in this application as well and really would have been a better choice imo(but, that's another topic). An example of a true thrust application would be the use of this style of bearing(thrust) in a helicopter's blade grips. I realize that, my argument was that the bearings used in these knives are produced as thrust bearings and are still ball style bearings. Maybe you misunderstood? He was saying that they were not thrust bearings and should not be called ball bearings but, any type of bearing(including thrust bearings), that use balls, is still a ball style bearing.

My understanding comes from formal schooling and many years as a professional mechanic, not the internet(although the internet can be a valuable resource).

I am not sure why we are still going on about this though as the OP question has been answered/resolved and this was a bit out of the scope of the question in the first place.
 
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Personal opinions are fine, your opinions on the matter at hand are obviously different from everybody else in the thread, but trying to pass them off as the only real answer is the problem you keep running into. Your schooling and opinions on what this thread's purpose is are not really relevant to the discussion being made, so bringing them up constantly doesn't really do anything to help get your point across.
 
KingMC said:
Personal opinions are fine, your opinions on the matter at hand are obviously different from everybody else in the thread, but trying to pass them off as the only real answer is the problem you keep running into. Your schooling and opinions on what this thread's purpose is are not really relevant to the discussion being made, so bringing them up constantly doesn't really do anything to help get your point across.
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What do you mean my opinions on the matter? I simple said that bearings used in knives like ZT's are thrust bearings when someone else said they werent(Mete). They are manufactured as thrust bearings, no matter how they are used. They are also ball style bearings. Those are facts, not my opinions. This threads purpose is outlined in the OP and was a simple question...

"Is "thrust bearings" just a fancy marketing name for phosphor bronzer washers, or is there an actual difference between the two?"

That has been thoroughly answered. This "the nomenclature of bearings" discussion we have gotten into is far beyond the OPers question and has now thoroughly derailed his thread. That is partly my fault and I apologize for that but, I was just clarifying what Mete said because I have a lot of experience on this topic.
 
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