# Self Lubricating Plastic



## Cride5 (Jun 16, 2010)

Lubing cubes is not only a time-consuming chore, but over time may _increase_ the rate of plastic wear. At the moment it seems that manufacturers pay little attention to the plastic used in their cubes, and I think much more could be done to produce cubes using plastic with a much lower coefficient of friction.

The problem with applied lubricants is that over time cube debris combine with them to create an abrasive paste. This increases dynamic friction and also increases wear. Because of this I regularly need to clean and re-lubricate my main speedcube. A similar problem occurs in the use of plastic gears. Example here:
http://www.eng-tips.com/viewthread.cfm?qid=27538

A solution to the problem is to use polymers with a low coefficient of friction. For example, Polytetrafluoroethylene (PTFE) - a soft polymer - can be combined with harder plastics to create a compound with high durability and low friction, see:
http://www.matweb.com/reference/coefficient-of-friction.aspx

I'm sure there are many more compounds available for this type of application, varying in price, hardness and friction coefficient. For example, here is a manufacturer which specialises in these:
http://www.ferret.com.au/c/Dotmar-EPP/Self-lubricating-super-plastics-n705667

No doubt cubes using this kind of plastic would be much more expensive, but if it worked it would certainly be an investment I would be prepared to make.

Are there any plastics experts with more info about the feasibility of this, and are there any cube manufacturers who have/would consider this?


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## AndyK (Jun 16, 2010)

Great idea, you should send this to Haiyan. He's already proven that people will pay a lot for a good cube (25 bucks for his memory cube). 

I'd buy one. Better yet, give me some AutoCAD designs, a block of your plastic of choice and I could make you a cube on a fabber.. (it'd probably not be hollow though)


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## Carson (Jun 16, 2010)

I am anxiously awaiting the first teflon cube.


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## ChrisBird (Jun 16, 2010)

Carson said:


> I am anxiously awaiting the first teflon cube.



Mmm, I love the smell of money going down the drain =p

How about carbon fiber?


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## daniel0731ex (Jun 16, 2010)

the AII have 3 versons that are made of 3 different type of plastics: ABS, PC, and POM. 

I think the POM AII would be what you are looking for.


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## Cubenovice (Jun 16, 2010)

Polymer chemist here...

POM would be the obvious choice for speedcubes. 
This becaus of its "hardness" and inherently low friction coefficient.
Can be even furter improved via lubricating additives like teflon but I doubt if you would feel the difference in a cube.

These additive also migrate to the surface of the material, possibly making stickers stick less.

I am a relatively new cuber but have never seen any cubes marketed as being POM based though.


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## rjohnson_8ball (Jun 16, 2010)

I remember when I was an undergrad at MIT back in the 70's I learned there was a very low of friction between stainless steel and Teflon. Maybe the edge and corner pieces could be Teflon coated, and the center pieces steel?


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## daniel0731ex (Jun 16, 2010)

Cubenovice said:


> Polymer chemist here...
> 
> POM would be the obvious choice for speedcubes.
> This becaus of its "hardness" and inherently low friction coefficient.
> ...



It's nice having a real expert here, instead of a wanna-be like me 

The versons of A2 with different plastic is quite common, but it's just that nobody ever posted about in this forum, and that "CubeforYou doesn't sell it", not many people ever knows about them or sells them (in western based stores).


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## daniel0731ex (Jun 16, 2010)

rjohnson_8ball said:


> I remember when I was an undergrad at MIT back in the 70's I learned there was a very low of friction between stainless steel and Teflon. Maybe the edge and corner pieces could be Teflon coated, and the center pieces steel?



or maybe teflon edge, stailness steel corner, and plastic center?


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## iSpinz (Jun 17, 2010)

daniel0731ex said:


> Cubenovice said:
> 
> 
> > Polymer chemist here...
> ...


The A-II's in my store are POM. They are awesome. They screws can get alot of gunk in them though.


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## dillonbladez (Jun 17, 2010)

I wouldn't say it's 'self-lubricating' but the idea of less friction sounds nice. I want a teflon cube D;


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## buelercuber (Jun 17, 2010)

ChrisBird said:


> Carson said:
> 
> 
> > I am anxiously awaiting the first teflon cube.
> ...



It could then be used as a weapon!!

no0b kidturns one side) "LOOK I SOLVED IT!!!" 

myself: CLUNK, "look , i solved you"

or a hammer! better yet, A BULLET PROOF CUBE!!!


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## radmin (Jun 17, 2010)

daniel0731ex said:


> the AII have 3 versons that are made of 3 different type of plastics: ABS, PC, and POM.
> 
> I think the POM AII would be what you are looking for.



How do you tell the three type AIIs apart?


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## Ashmnafa (Jun 17, 2010)

The title fooled me. It isn't self lubricating, it is just a different plastic, but I still like the idea.


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## Cubenovice (Jun 17, 2010)

Ashmnafa said:


> The title fooled me. It isn't self lubricating, it is just a different plastic, but I still like the idea.



Well actually they can be self-lubricating. As mentioned the additives might migrate to the surface (additive dependent).
But even if they do not migrate at all they are still self- lubricating.
As the surface gradually wears new addtive particles become exposed.

For optimal performance it is indeed a good idea to not have the exacts same materials touching eachother.
Something that can happen with POM gears on POMm axles is a squeeking sound. This can be resilved by having one component in a different material. However it could also be enough to use two different grades of POM.


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## Cride5 (Jun 17, 2010)

Cubenovice said:


> Polymer chemist here...
> 
> POM would be the obvious choice for speedcubes.
> This becaus of its "hardness" and inherently low friction coefficient.
> ...



Hi Cubenovice, thanks for your input.

So from what I gather the best set up would be to use two 'grades' or types of plastic. Probably using the cheaper (normal friction) one for the corners/centres and the more expensive (low friction) one for the edges. It would probably be useful if the edge pieces were designed so that both external surfaces (for attaching stickers) were engineered out of the non-slippery plastic, so that only the internal surfaces have the self lubricating properties. Do you think this would be possible? 

Could you recommend any plastics manufacturers who might be able to build a prototype like this? If so, what would be a reasonable estimate for the cost? Ideally the cubies would be based on the FII design, possibly with modifications to the construction of the edge caps.


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## Gurplex2 (Jun 17, 2010)

pfft, there's already a million good 3x3's.


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## Deleted member 2864 (Jun 17, 2010)

Gurplex2 said:


> pfft, there's already a million good 3x3's.



Then why are people still designing new ones?


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## Cubenovice (Jun 17, 2010)

Hi Cride, to be honest I think the hassle of having the additional parts required to have cubies with specific sides in specific materials would outweigh the possible benefits.
I do not think there is actually much to gain given the construction and "operating" speed of a proper speed cube.

Wen I look at my QJ4x4x4 for instance I would actually prefer it to have a little m*ore* friction.

For prototyping it is no use to go to plastics manufacurers. They only make the material . A cube manufacturer would be the ideal person to play around with material combinations for all components.
This because they have got acces to all the molds.

With modern 3D prototype techniques like FDM, SLA or SLS you can nowadays make some very nice functional prototypes. But you cannot make the parts in the injection molding plastics you would use for the final product.

An idea could be using an SLS proto with custom cubies designed in such a way that you can mount strips of testmaterials on them.
For individuals an easy prototyping service is http://www.shapeways.com
Polyamide SLS pieces go for 1.5 USD per cm³ but you will have to prepare the 3D data.

If you have some spare cubes you can actually do some experimentation yourself. It is "just" a matter of applying some thin sheets of the materials onto specific areas of your cube. For the best prototyping you cannot beat some good old tinkering.

I have various pieces of POM (and other materials) available if you are up for it


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## daniel0731ex (Jun 17, 2010)

Guojia is actually the first to mess around with plastics other than ABS for cubes xD

the A5 have only ABS and PC versons, because the POM A2 is said to be too "squeaky"; so they didn't use it on the A5, which have a lot more surface area that contacts each other on the pieces.


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