Which o-ring material would be best to keep something from sliding? This is not for automotive use: I am trying to fix something that is broken. The most common materials are Buna-N, Silicone, EPDM, Polyurethane, and Viton (if I got the spelling correct. It costs about $10 a package for the o-rings, so I don't want to buy them all to try out.
Which o-ring material is the stickyest (friction)?
- Thread starter Loobed
- Start date
- Status
I'd vote for polyurethane. This material is often used for the self-adhesive "rubber" feet found on the bottom of stuff. It's a fairly durable, non-marking elastomer.
A normal o-ring is neoprene since its not effected by oil or gas.
Originally Posted By: Rick in PA
I'd vote for polyurethane. This material is often used for the self-adhesive "rubber" feet found on the bottom of stuff. It's a fairly durable, non-marking elastomer.
Is a softer o-ring stickier? Most of the o-rings I checked out are between A70 and A75 in hardness. They make a soft Buna-N that is A50 hardness.
I'd vote for polyurethane. This material is often used for the self-adhesive "rubber" feet found on the bottom of stuff. It's a fairly durable, non-marking elastomer.
Is a softer o-ring stickier? Most of the o-rings I checked out are between A70 and A75 in hardness. They make a soft Buna-N that is A50 hardness.
Last edited:
Originally Posted By: Donald
A normal o-ring is neoprene since its not effected by oil or gas.
I sort of thought it was viton that was most resistant to gas.
A normal o-ring is neoprene since its not effected by oil or gas.
I sort of thought it was viton that was most resistant to gas.
I can only speak from injector and automotive use. Common o-rings are usually polished to make installation easier.
The softer it is the stickier it will be, you can knock the shine off with some 400 or finer paper and water.
Nitril (Buna-N) 50 is pretty soft but silicone will probably be the stickiest from what i have experienced putting them together and the amount of lube they require.
Does it have to be an o-ring? There are head seals that fit on the bottom of some injectors that are very soft and unpolished, they will have a greater contact area also.
What size do you need?
The softer it is the stickier it will be, you can knock the shine off with some 400 or finer paper and water.
Nitril (Buna-N) 50 is pretty soft but silicone will probably be the stickiest from what i have experienced putting them together and the amount of lube they require.
Does it have to be an o-ring? There are head seals that fit on the bottom of some injectors that are very soft and unpolished, they will have a greater contact area also.
What size do you need?
Gotta ask... it really would help to know what this is for.
There may be alternative solutions in addition to a more informed decision.
There may be alternative solutions in addition to a more informed decision.
Quote:
I sort of thought it was viton that was most resistant to gas.
It is in general automotive use. Nitril (Buna-N) is also used sometimes but it was more common years ago.
There are o-rings that are superior to viton in their resistance to fuel and chemicals but cost a fortune, they are not really needed in automotive use.
I service some 1,000 psi injectors that use FFKM o-rings and they cost about $4 ea vs .04c for Viton 75 of the same size.
Kalrez brand (FFKM)is a more common one.
I sort of thought it was viton that was most resistant to gas.
It is in general automotive use. Nitril (Buna-N) is also used sometimes but it was more common years ago.
There are o-rings that are superior to viton in their resistance to fuel and chemicals but cost a fortune, they are not really needed in automotive use.
I service some 1,000 psi injectors that use FFKM o-rings and they cost about $4 ea vs .04c for Viton 75 of the same size.
Kalrez brand (FFKM)is a more common one.
Originally Posted By: Trav
Does it have to be an o-ring?
What size do you need?
Yes. It has to fit around a 1/8" shaft, with an OD smaller than 1/4". It will be used for feeding paper tape. A replacement unit costs $600.
Does it have to be an o-ring?
What size do you need?
Yes. It has to fit around a 1/8" shaft, with an OD smaller than 1/4". It will be used for feeding paper tape. A replacement unit costs $600.
Polyurethane rollers are commonly used in paper handling. Even hard polyurethane is quite "grippy".
Is it for a Betterpack?
Is it for a Betterpack?
Originally Posted By: tom slick
Polyurethane rollers are commonly used in paper handling. Even hard polyurethane is quite "grippy".
Is it for a Betterpack?
I don't know what a Betterpack is.
It is a measuring machine that keeps track of the dimensions than calculates the average and standard deviation. You can chose to measure a round part, check the part every 45 degrees, than it will give you how out-of-round the part is. It is a 25+ year old device, but it still does what it is suppose to do except print out the result. I can write down the results by hand from the digital display, but that takes time, and hand written records are not good for quality control records. Plus I am sometimes lysdexic, I mean dyslexic.
Polyurethane rollers are commonly used in paper handling. Even hard polyurethane is quite "grippy".
Is it for a Betterpack?
I don't know what a Betterpack is.
It is a measuring machine that keeps track of the dimensions than calculates the average and standard deviation. You can chose to measure a round part, check the part every 45 degrees, than it will give you how out-of-round the part is. It is a 25+ year old device, but it still does what it is suppose to do except print out the result. I can write down the results by hand from the digital display, but that takes time, and hand written records are not good for quality control records. Plus I am sometimes lysdexic, I mean dyslexic.
A Betterpack is a paper tape dispenser for packages.
http://www.betterpackages.com/products/dispensers/electric/bp555e.shtml
Is your machine some type of CMM?
http://www.betterpackages.com/products/dispensers/electric/bp555e.shtml
Is your machine some type of CMM?
Originally Posted By: tom slick
Is your machine some type of CMM?
You could call it a poor mans CMM
This is something what it looks like SPC printer
Mine looks like a 25 year old calculator with a printer attached.
It has one of these attached to the calculator thingy digital gauge
Is your machine some type of CMM?
You could call it a poor mans CMM
This is something what it looks like SPC printer
Mine looks like a 25 year old calculator with a printer attached.
It has one of these attached to the calculator thingy digital gauge
- Status
