Gasket Discussion, Comparison PTFE vs Viton vs Polysteel vs Solid PTFE or Envelope ?

[SquattingBull]

Love the side by side. Cant wait for that report back. Short of something drastic is seems like what you are losing in usability of viton to PTFE does not even compare what seems like a very very small amount of potential contaminant. Also, I realize this may not be the most popular topic but inhaling hot vapor/smoke/whatever as a source of chronic irritation to your lungs and respiratory system is most likely a mountain to a mole hill in potential damage to your pulmonary system. The risk we take while imbibing via smoking.....

 

[Sunfire]

Vape pen! Just got a fancy new Nero technology one! Yay! I gotta get me a setup to put the pen up to a water pipe of some sort. Water filtration will help our lungs greatly!

Idk why I didn't mention this before. Dwight wanted me to mail him the super shitty screen gaskets I had so I soaked them in coconut oil cause I had no cheap oil. Just put the 4 inch screen gaskets, dirty as fuck, into a small saucepan with the heat on mega ultra low just to keep the oil liquid. Came back an hour or so later and gave em a quick warm water wash and them put them into soapy warm water to soak again as soap is an emulsifier and that'll get all the leftover oil off. Then came back, warm water rinse again and dries them by not whipping but pat,tamped it to dry. Worked great as far as cleaning it is concerned. Wish I would have scrubbed it dry though to look for contamination. Maybe the coco oil will help condition the gasket and preserve it's lifespan. Perhaps even put a nice coating on it and hold contaminants back? I gotta call dwight today anyways I'll ask him what he thinks about all this and report back

 

[Sunfire]

Just got off the phone with dwight.

He said that iso should have no reaction with viton but I informed him of our obsevations. He suggested at first it could be the release agents, but mostly likely it's carbon. Carbon, derived from soot. Is used like a fiber to strengthen the material. Like straw in clay or gravel in concrete. The actual polymers should not be leaching as they are bonded. So most likely is naturally derived elemental carbon that we see on our paper towels which might be rising to the surface from the clamping and unclamping of the gaskets. If you smoke flowers, your smoking way more carbon than the ratios we see on the paper towel, spread throughout the entirety of the product produced in that run. Plus the part of the actual gasket that touches the solvent is very little compared to what we scrub. The solvent isn't physically scrubbing the gasket either. I'm feeling safer now.

He said coconut oil should be fine and it will not however condition the gasket because the viton should have no permeation of any kind, which is the point of viton.

I informed him of the current side by side test of coconut oil and iso and he said he's going to do the same thing at his desk.

 

[montroller]

Results are back, and it isn't looking good...

I was trying to think of an alternative for a second but it was pretty obvious. The answer is PTFE.

Any reviews of those enveloped gaskets Roji?

 

[Sunfire]

Hmmm. Ptfe envelope gaskets with custom made screens

 

[montroller]

So I was thinking a little more about the tests and I don't think my results can truly be valid. Neither gasket is new and one was bought from glacier while the other was bought from Amazon.

I think a proper test would have 2 brand new gaskets from the same supplier.

But honestly it is probably just easier to grab enveloped gaskets or find some PTFE ones that actually work.

 

[Sunfire]

New ones might have the carbon release on it. I believe dwight how he explained how they are made and how the carbon could be working it's way out prom the compression and release we always do to gaskets. Which is why they degrade and become weaker rather quickly.

An envelope ptfe that doesn't cold flow should hopefully last longer right? That's enough to sell me right there.

 

[jpdnkstr]

I love this place, it always makes me feel sooo good about my own OCD issues!

 

[Roji]

Thank Horatio Delbert. He brought this to light in my lab.

http://www.brewerygaskets.com/1-5-teflon-envelope-epdm-insert-tri-clamp-gasket/

http://www.coleparmer.com/Product/PTFE_Gasket_100_MESH_Size_1_1_2_Tri_Clamp/EW-30538-86

 

[flatslabs]

EPDM is not compatible with most solvents or petroleum derivatives (certainly not butane) as far as I know, so make sure you are getting the Viton or other

 

[Roji]

EPDM is not compatible with most solvents or petroleum derivatives (certainly not butane) as far as I know, so make sure you are getting the Viton or other

the epdm has no contact with the solvent. That is the point of an envelope gasket.

 

[flatslabs]

Fair enough, for some reason I thought the material was exposed on both sides of the gasket, what will you be using to clean them?

Also interesting to note is the temperature rating on the Viton ones vs the EPDM.
I also see Dixon has FKM and EPDM envelope gaskets in their catalog, but didn't see Viton. Something to do with DuPont patent issues and Viton trademark?

 

[Roji]

I clean them with 99% iso. Works well.

 

[BrainChild]

Isn't viton just dupont's brand name for FKM?

And here are PTFE envelope gaskets with viton inserts: https://www.gvc.net/p/23/ptfe-viton-sanitary-tri-clamp-envelope-gaskets. I'm getting some 6"

Though I gotta say, the tuf-flex seems to be the best choice, though very pricey!

http://www.rubberfab.com/products/sanitary-gaskets/specialty-gaskets/tuf-flex

 

[flatslabs]

Kind of... Viton is a DuPont trademark, but just like Teflon there are a number of different formulations of material under the Viton brand name.

DuPont lists several kinds of Viton with varying degrees of chemical and hydrocarbon compatibility so I was more or less wondering what the dixon FKM are equivalent to.

http://www2.dupont.com/Plastics/en_US/pfo/assets/downloads/viton/Viton Selection Guide.pdf

What I was suprised by was from the page Roji posted the Viton envelope gaskets were only rated down to 5 deg Fahrenheit compared to the EPDM which were -60F

 

[SquattingBull]

Roji I only see up to four inch on those enveloped gaskets and while it isn't much a hassle to swap if they work wouldn't the large gaskets still be the major source of leaching if that is happening? The column gaskets are getting passed over by solvent in the process but the larger bottom gasket on the collection pot (for many systems discounting a tall shatter platter or welded bottom) are certainly being exposed to oil for a much longer period of time and have more surface area. As GW has pointed out these larger gaskets are going to be even harder to seal as the diameter increases so I wonder if that may be why they are not on there. I am not convinced that its a problem at this point but I am all about erring on the side of caution for the consumer if a better product tests out to be superior or at least equal in functionality.

 

[Sunfire]

I'm not done with the viton black smudges yet!

I had some never used gaskets laying around that I decided to play with. The two 4" 120 mesh removable screen ones are from brewerygaskets.com which are sourced from vietnam. The two 4" 20 mesh gaskets are from an unknown source that were given to me back in December. The 4" and 2" regular ones are from glacier.

I rubbed them all with iso, very well, and NO black smudges, none! So then I took a used gasket and rubbed the outside of it with iso where no r600 or even steel ever touches it and there was black smears on the towel. So then I took a different gasket and rubbed the outside with a dry, new paper towel, and black smears came off it, completely dry and new paper towel!

I didn't think soaking them was a good variable to include in this experiment because the gaskets never get soaked for longer than a few minutes in r600 and only the very inside even touches solvent.

So, here's what we have learned; new gaskets don't rub off with iso, Used gaskets rub off black with oil and with a dry towel, Parts of used gaskets that never see solvent rub off black.

Logically, I feel it's safe to assume the black stuff rubbing off is NOT solvent related. The fact that the new ones didn't rub off, and the used one do, considering we can now rule out solvent as the cause, only leaves the variable of use which involves compressing and decompressing. This adds evidence to dwight ' s theory that it's carbon working it's way up to the surface from the compression and decompression.

I have an analytical chemist in the family. We discussed gettingn the black smudges tested but it seems like it would be extremely hard. Control towel and test towel would have to be EXACTLY the same size. Test towel would need to have as much black rubbed onto it as possible. Towels would have to be compared by weight before testing for carbon. Considering the paper towels are mainly carbon, and the test towel would be losing lots of fibers while rubbing, the results will not be an accurate representation. I can have the testing done for free if any one comes up with a clever way to do it?

Furthermore, the chemist family member suggested that considering the source (soot) it's more likely to be graphite which is simply a chain of carbons. This would be better because it's heavier and would have more chances of staying behind on your nail. I'm still in the heaviest belief that if you smoke flowers past the point of green, and especially from black to grey ash, you are smoking an incomparable amount of more carbon than you would from dabbing product that had any contamination from the gaskets. Especially considering it's only the very inside of the gasket that touches the solvent, and the liquid solvent is "rubbing" the gasket.

This is similar to alot of shit we deal with, it works for our purposes but wasn't made for our purposes.

Now I'm not saying to not buy envelope gaskets, I'm totally down to get some, especially since you guys have been doing some research into which one will be best for our purposes. My conclusion simply is that I feel the viton is still safe until it can be proven otherwise. I like sustainable products and as I said before, if the envelope gaskets last longer that's enough to sell me.

 

[Sunfire]

Roji I only see up to four inch on those enveloped gaskets and while it isn't much a hassle to swap if they work wouldn't the large gaskets still be the major source of leaching if that is happening? The column gaskets are getting passed over by solvent in the process but the larger bottom gasket on the collection pot (for many systems discounting a tall shatter platter or welded bottom) are certainly being exposed to oil for a much longer period of time and have more surface area. As GW has pointed out these larger gaskets are going to be even harder to seal as the diameter increases so I wonder if that may be why they are not on there. I am not convinced that its a problem at this point but I am all about erring on the side of caution for the consumer if a better product tests out to be superior or at least equal in functionality.

I agree completely, I don't like scraping against any gasket regardless on material. I'll be upgrading to a welded base asap!

 

[Roji]

I have 3" 6" and 12" envelope gaskets ordered. They do exist.

I'm going the simple route. No black gaskets means no black contaminate. No testing or observing or hoping or praying necessary.

 

[SquattingBull]

I'm not done with the viton black smudges yet!

I had some never used gaskets laying around that I decided to play with. The two 4" 120 mesh removable screen ones are from brewerygaskets.com which are sourced from vietnam. The two 4" 20 mesh gaskets are from an unknown source that were given to me back in December. The 4" and 2" regular ones are from glacier.

I rubbed them all with iso, very well, and NO black smudges, none! So then I took a used gasket and rubbed the outside of it with iso where no r600 or even steel ever touches it and there was black smears on the towel. So then I took a different gasket and rubbed the outside with a dry, new paper towel, and black smears came off it, completely dry and new paper towel!

I didn't think soaking them was a good variable to include in this experiment because the gaskets never get soaked for longer than a few minutes in r600 and only the very inside even touches solvent.

So, here's what we have learned; new gaskets don't rub off with iso, Used gaskets rub off black with oil and with a dry towel, Parts of used gaskets that never see solvent rub off black.

Logically, I feel it's safe to assume the black stuff rubbing off is NOT solvent related. The fact that the new ones didn't rub off, and the used one do, considering we can now rule out solvent as the cause, only leaves the variable of use which involves compressing and decompressing. This adds evidence to dwight ' s theory that it's carbon working it's way up to the surface from the compression and decompression.

I have an analytical chemist in the family. We discussed gettingn the black smudges tested but it seems like it would be extremely hard. Control towel and test towel would have to be EXACTLY the same size. Test towel would need to have as much black rubbed onto it as possible. Towels would have to be compared by weight before testing for carbon. Considering the paper towels are mainly carbon, and the test towel would be losing lots of fibers while rubbing, the results will not be an accurate representation. I can have the testing done for free if any one comes up with a clever way to do it?

Furthermore, the chemist family member suggested that considering the source (soot) it's more likely to be graphite which is simply a chain of carbons. This would be better because it's heavier and would have more chances of staying behind on your nail. I'm still in the heaviest belief that if you smoke flowers past the point of green, and especially from black to grey ash, you are smoking an incomparable amount of more carbon than you would from dabbing product that had any contamination from the gaskets. Especially considering it's only the very inside of the gasket that touches the solvent, and the liquid solvent is "rubbing" the gasket.

This is similar to alot of shit we deal with, it works for our purposes but wasn't made for our purposes.

Now I'm not saying to not buy envelope gaskets, I'm totally down to get some, especially since you guys have been doing some research into which one will be best for our purposes. My conclusion simply is that I feel the viton is still safe until it can be proven otherwise. I like sustainable products and as I said before, if the envelope gaskets last longer that's enough to sell me.

Yep this is pretty much exactly how I feel. I am totally down to swap to something else if it comes up that it can be sealed effectively under all conditions and at appropriate sizes and provides a better service but I am not gonna freak out about it either. The fact of the matter is inhaling smoke or hot vapor is not the greatest for your lungs (not just from a cancer perspective but from COPD and interstitial lung dx as well) and the likelihood that these viton gaskets are some unforeseen terrible entity seems very unlikely thus far. I personally like having a removable bottom and our new machine we're building right now will either have a shatter platter or flat bottom depending on the application but to each his own. I definitely agree scraping along the seal is a no no and for that reason we don't and I can for sure see the appeal of a welded bottom depending on your preference and tek. Sunfire cool input from the analytical chemist btw I bet thats an awesome person to get to run stuff past.

As a closer, Roji thanks for posting all the links and I look forward to hearing some of your results on the function of these bad boys and will happily swap once they have been vetted by trusted sources like yourself. The enveloped gaskets are a super cool idea to get the best of both worlds and that much is not in doubt.