Materials for a bearing button

[antithesis]

I've seen it done here and there, on surfaces that you want to reduce metal on metal wear and galling, like hammers for instance, people have made or bought buttons like the old maccari buttons as a plain bearing of sorts

Now I've done homework aplenty on the topic, but I'd like to know what some of you guys would use, and why

Nothing off limits here either, it can be a filled or virgin polymer, different alloy of lead bronze or brass. Anything goes, what would you use and why( wear resist, toughness, low COF, price, convenience, availability, tell me what you like about it)

[Rabbitstopper]

Phospher bronze maybe far from hard wearing but more a material that can be easily machined and replaced also has self lubricating properties. What would the application be? If a thurst bearing type application just go hard.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://simplybearings.co.uk/shop/&ved=2ahUKEwiEwua3uPrnAhWktXEKHXTDAr4QFjAAegQIBBAD&usg=AOvVaw0t6RCy68tsW9aNzAbMYjNA

[antithesis]

Phospher bronze maybe far from hard wearing but more a material that can be easily machined and replaced also has self lubricating properties. What would the application be? If a thurst bearing type application just go hard.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://simplybearings.co.uk/shop/&ved=2ahUKEwiEwua3uPrnAhWktXEKHXTDAr4QFjAAegQIBBAD&usg=AOvVaw0t6RCy68tsW9aNzAbMYjNA

It would be a sliding button mounted in a shallow hole in the top of a hammer, to reduce or eliminate the drag between the top of the hammer and tube...it would be technically more closely defined as a plain linear bearing.  It would serve an almost identical purpose to the macarri buttons they had for Springer pistons to reduce friction and take up any space between tube and piston, if you're familiar. I know it's splitting hairs but that's just how I am.. something long wearing and self lubricating would be about ideal, and can be had in rod form, maybe 1/8 to 3/16

[KnifeMaker]

I've used three materials so far for a difficult hammer in a non drop sear AG.
First I used nylon rod. Couldn't find any quickly so for a test, I cut a .22 cal. white nylon type jag and used the narrow shaft part for buttons top front, and rear bottom on a Maximus hammer. worked Very well!


Ordered Delrin rod, and it worked well also. I wanted to order PTFE next, but never did. 


I had an issue with the Rainstorm II non drop sear wearing the underside and leaving chatter and galling marks on the entire length of the hammer.


In a fit of desperation, I have a good selectioin of pull ties here and selected a tough type used for LEO and MIlitary type handcuffs. It is also used industrially.


I milled a slot in the bottom of the hammer and fitted the smooth side out and affixed with plastic to metal Epoxy. It totally stopped the damage and the fine metal dust I was finding in the trigger group.


both together gave better shot to shot averages, easier cocking, and stopped the terrible wear!


I also ordered some Anti-Friction tape, but the Mini Raptor arrived and never got around to trying it in the RS or Maximus.


They kinda took a back seat. 


Knife

[antithesis]

I've used three materials so far for a difficult hammer in a non drop sear AG.
First I used nylon rod. Couldn't find any quickly so for a test, I cut a .22 cal. white nylon type jag and used the narrow shaft part for buttons top front, and rear bottom on a Maximus hammer. worked Very well!


Ordered Delrin rod, and it worked well also. I wanted to order PTFE next, but never did. 


I had an issue with the Rainstorm II non drop sear wearing the underside and leaving chatter and galling marks on the entire length of the hammer.


In a fit of desperation, I have a good selectioin of pull ties here and selected a tough type used for LEO and MIlitary type handcuffs. It is also used industrially.


I milled a slot in the bottom of the hammer and fitted the smooth side out and affixed with plastic to metal Epoxy. It totally stopped the damage and the fine metal dust I was finding in the trigger group.


both together gave better shot to shot averages, easier cocking, and stopped the terrible wear!


I also ordered some Anti-Friction tape, but the Mini Raptor arrived and never got around to trying it in the RS or Maximus.


They kinda took a back seat. 


Knife

I think unfilled ptfe would wear pretty fast, I wish Kel f was easier to source.

Zip ties huh?

I like that idea alot, I may give that a go if my mds hammer starts getting chewed up

[Motorhead]

HOW said material is attached or machined makes a HUGE difference.   Adhesives even super glue / CA won't stick to nylons even tho Nylons are very very tough and make for an excellent bearing in a linear application.
Forms of Acetal such a AF grade ( teflon fortified ) you can glue with CA and also wears very well.
Machining to have said material in a containment pocket is the most ideal outside of the entire hammers outer shell being made from it.

[antithesis]

HOW said material is attached or machined makes a HUGE difference.   Adhesives even super glue / CA won't stick to nylons even tho Nylons are very very tough and make for an excellent bearing in a linear application.
Forms of Acetal such a AF grade ( teflon fortified ) you can glue with CA and also wears very well.
Machining to have said material in a containment pocket is the most ideal outside of the entire hammers outer shell being made from it.

That's exactly what I had in mind, well within my means.  It wouldn't be hard to drill a specific size and depth pocket, and take a short piece of rod and file a slight taper for an interference fit..

Most polymers id consider for this would not be easily glued without expensive adhesives and primers, and if the button wears out somehow,  in a pocket fit I could easily replace it...tube should hold it just fine even without a taper. So that being the case if I can get it, or already have it, in rod stock it won't take much to make a simple insert...still love that zip tie idea, may make the potential application of non steel hammers alot wider in scope instead of worrying about destroying a custom made piece with incompatible trigger parts

Alternately I had even considered polymer bearing balls if I could make the pocket just right, but rod stock seems most practical

[nced]

I've seen it done here and there, on surfaces that you want to reduce metal on metal wear and galling, like hammers for instance, people have made or bought buttons like the old maccari buttons as a plain bearing of sorts

Now I've done homework aplenty on the topic, but I'd like to know what some of you guys would use, and why

Nothing off limits here either, it can be a filled or virgin polymer, different alloy of lead bronze or brass. Anything goes, what would you use and why( wear resist, toughness, low COF, price, convenience, availability, tell me what you like about it)

LOL....while the older HW springers I bought (R10, R9, HW77k) had a rather sloppy fit to the receivers which benefited from "buttoning", since the HW piston skirts  are hardened and the receiver tubes aren't hardened there will be little (or no) galling between the dissimilar metals with proper lubing. The only benefit of buttoning is simply the fact that properly fitted buttons center the piston better and the buttons do minimise metal to metal sliding if the buttons are Delrin. I was going to button my HW95 when I received it a couple years ago and work the receiver ID for an oring piston seal conversion. when I disassembled the gun I found that the piston to receiver fit was already good and the receiver ID was already finished similar to what I do with oring piston seal conversion so both the HW95 receiver ID and piston skirt were "unmollested"..........
Gone were the cross-hatch "grooves" common with the older HW springers I bought after the "ham fisted cross-hatchers" were done. Here is Factory my HW95 receiver finish straight from the box.........

The piston fit the receiver so well that all I did was polish the skirt a bit and allowed the Dupont Krytox GPL205 grease to do it's magic.........


Anywhoo....to directly answer the original quaestion, when I do add buttons I make mine from Delrin rod. Sometimes it's black Delrin, Sometimes it white delrin.........

[KnifeMaker]

For the buttons, i have had very good luck making the pocket a press fit. No adhesive needed.


For the pull tie I milled a slot i the steel hammer and only allowed it to be 4 thou. proud. I has work in the Rainstorm for over two years now.


It was showing extreme wear from the sear riding it, so I obtained a new hammer and installed the strip in the milled slot.


It has thousands of shots at high fpe showing NO appreciable what what so ever. Even if it did wear, it would be a  simple matter to replace it.


as a side benefit, the sear shows much less wear over the long haul. A win-Win!


JB makes an epoxy , made for adhering to different plastics. Works pretty well. [size=78%]  [/size]


Knife 

[antithesis]

Years back I made an inquiry about a sample request from aron alpha (parent company of Krazy glue) under the pretense of being a full fledged customs shop (in my dreams), filled out a few questionnaires regarding applications and materials, and these guys sent me so much of almost every kind of ca glues that they have, in 2OZ BOTTLES!!,  4 OZ bottles of primer for delrin and such, toughened, methyl, ethyl, silica thickened, wicking, seriously there was nothing I couldn't glue with CA , it all thickened and went bad after a few years but man I even experimentally glued together a cracked in two AF Condor breech and IT HELD! 

I've sadly never had ca that worked that well again.

Knife,

I was thinking about trying uhmw in place of nylon just to try it, I've got a few sheets and it's definitely tough stuff, I think rivalling nylon in many regards, except for structural applications, but in strips and sheets or for shimming I swear by it

[antithesis]

Oh, and nced,

Have you ever noticed any difference between the two? Unless otherwise noted, like carbon filled and such, I understand there to be no actual difference except dye.. I've always wanted to know what a 13xx poppet(white) is made of. Seems like either delrin or nylon, but the mrod poppet(black) is definitely delrin and WAY harder

[nced]

Oh, and nced,

Have you ever noticed any difference between the two? Unless otherwise noted, like carbon filled and such, I understand there to be no actual difference except dye.. I've always wanted to know what a 13xx poppet(white) is made of. Seems like either delrin or nylon, but the mrod poppet(black) is definitely delrin and WAY harder

Nope.....no difference as far as I can tell, however McMaster Carr also offers a Teflon filled Delrin which is Brown as well as a red or blue variety that has added silicone in the mix. Blue is also known as Turcite A and it's stronger than red which is Turcite X which is more slippery than blue.
https://www.mcmaster.com/acetal

[KnifeMaker]

Hope I can get the pics of a button job and striker here.

[Atom]

Phenolic cotton is much better from Delrin...
https://www.ebay.com/itm/1-Ft-Of-Natural-Brown-Rolled-Molded-Phenolic-Rod-312-Dia-Knife-Handle-Pins-/131554025393

[antithesis]

Phenolic cotton is much better from Delrin...
https://www.ebay.com/itm/1-Ft-Of-Natural-Brown-Rolled-Molded-Phenolic-Rod-312-Dia-Knife-Handle-Pins-/131554025393

Phenolic huh? That's an interesting proposal, it would definitely last that's for sure.

How well does it machine or file? I only wonder about friction coefficient and the long term possibility and effect of cotton fibers in the mechanism...probably negligible. Ive known it being used in light duty gears and drives, that also may be worth looking at too

Teflon filled delrin or moly filled for that matter have had me looking harder at filled polymer, I'd need to look at the exact composition of the fillers, I have looked extensively at bearing grade filled polymers but can arrive at no real ideal conclusions, and you can't get any tech advisers on the horn for a couple feet of rod or a 200 usd minimum potential purchase

[Atom]

Yes, phenolic cotton+ptfe
https://m.tufnol.com/tufnol-grade-2f-3-ptfe.aspx

[nced]

Phenolic cotton is much better from Delrin...
https://www.ebay.com/itm/1-Ft-Of-Natural-Brown-Rolled-Molded-Phenolic-Rod-312-Dia-Knife-Handle-Pins-/131554025393

Hummmm....why is it better? Years ago working as a machine designer for an induction heating and melting design/fabricating company the "Phenolic materials" were used as an electrical insulator. The phenolic materials came in different mixtures, some filled with fiber glass, some paper, some jute, some cotton, etc. I'm thinking that unless the user was careful the "phenolic" buttons could do more wear than the sliding metal to metal parts if an abrasive form is chosen......


Anywhoo........Delrin/Acetal is actually a bearing material, some tough enough for making plastic gears and it has worked well whenever I used it.

Some button installations  I have seen "issues" with are the "glue on button installations". I personally mill recesses for my buttons so even if they "work loose" (hasn't happened yet) the buttons are captive between the piston shell and receiver ID so they won't migrate through the gun. On the other hand, here are a couple pics of a piston from a gun sent to me that had a "glue on button" treatment..........

[antithesis]

Yes I don't care what kind of adhesives you use, I simply can't trust it to stay put in an application like this, especially using the kinds of plastics id consider...most glues even with primer are marginal on bearing plastics like delrin, polyethylene, peek, nylon, etc.  Especially something that is self lubricating in nature..

It's too easy to mill a pocket and use either a bearing ball or better a piece of rod press fit and captive. 

You being a springer guy I see , I was sure if anyone could confirm button failures, even with surface prep, that's alot to ask of any adhesive

[mobilehomer]

The Crosman NP2 has a buttoned piston. It uses 3 - 4mm Teflon balls in pockets.  I replaced them with Delrin balls.

[antithesis]

The Crosman NP2 has a buttoned piston. It uses 3 - 4mm Teflon balls in pockets.  I replaced them with Delrin balls.

Teflon is WAY too soft for that in my opinion.   They were BALLS? Not posts or buttons or anything? Teflon balls would seem like they would fall apart in no time