You are wrong. Don't just repeat stuff you read/see on the web.
Three years of use and not a speck of corrosion.
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Gx filter is here
- Thread starter 1900colt
- Start date
Three years of use and not a speck of corrosion.
If that worried about corrosion just use a clear report cover and make a tube to slide in..
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Lots to read, many discussions to be found, here is one https://airgunforums.co.uk/threads/molecular-sieve-and-aluminium-containers.37533/
I too had read that it needs a barrier, without me doing my own detailed research I have no opinion yet, but you may be right!
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Pressurizing the sieve is what makes it absorb water vapor effectively.
The cheap Tuxing type without a PMV are ineffective until the tube reaches a high pressure. The lower pressure air flowing into the gun is not dry.
Yes, I seen years of verbiage on the topic. Lots saying it will happen. None that I recall actually showing damage.
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I guess that is what I mean. The air doesn’t start flowing into my gun until everything is around 2200 psi anyway. However, yes there is a volume of air that gets past the sieve for sure. Just seems a small amount but I guess over time probably ads up.
I have the gx filter coming. I plan to run it on my cs2 for direct gun fills. I will use the larger filter on the cs4 for topping off 6.8 L bottles. For that filter I bought a one way foster valve , like you find on a lot of guns. To that I screwed on a bsp foster adapter like you have to buy for many fill probes. With that on the output side of the filter I can just open my tank valve and the compressor won’t start filling until the filter pressure equalizes the tank pressure.
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A couple of thoughts on the issues of liners and PMVs . . . lots of bad info out there, much of it spread by one who refers himself an airgun scientist, but is really more of a marketing dude . . .
On liners, they are probably a good idea, but even without one it's not like the cylinder is just going to explode or anything. If your filter does not use one, simply inspect the inside of the tube each time you change desiccant and if you see any discoloration, take action. And if you change media before it gets saturated, there will likely be no issue anyways. And if you want to use one, as already stated, simply make your own and add it in there. Not a bad idea.
On PMVs, it is important to know that desiccants will work fine at lower pressures - if you doubt it, weigh out a sample and leave it out in the open at atmospheric pressure and then weigh it again a day later. The statements that the filters "won't work" at lower pressure (thus without a PMV) are simply wrong. What is true is that in the "right situation" a PMV can increase the efficiency of a desiccant filter, and they do this through increased dwell time via reduced flow rate through the media. Multi stage air compressors basically put out a constant volume of atmospheric air regardless of output pressure, and thus the flow rate (and thus inversely the dwell time) through a given filter is higher when the pressure is lower, and lower when the pressure is higher.
So the "right situation" for needing a PMV is when filling a reservoir from empty (or at least close to it). As airgunners, we almost always fill to reservoirs that already have at least 100 bar or more in them - maybe one fill out of hundred (or less) is from empty (especially if we fill tanks from our compressors, and the tanks fill the guns). For breathing air (SCUBA and firefighting), the opposite is true - almost every fill is from close to empty, as divers try to maximise the time they have underwater with each tank (maybe not as much with fife fighters - they want to get out of the fire as soon as they can). These situations are where a PMV is highly beneficial, and should be used. Filters with PMVs are common in the dive industry. They don't hurt anything in an airgunning application, but are not beneficial or needed. If one is worried about that one in a hunder fill from low pressure, simply realize that each subsequent fill (with more fully dired air) after it will dilute out any small water vapor level that got through the first part of that initial fill - nothing much to worry aobut, unless you plan to fill the reservoir and then simply store it unused for a long time (and even that case is worlds better than the folks that fill without the use of a desiccant filter at all).
The attempt to convince airgunners that we need a PMV in their filter is purely marketing - cynically, the process of convincing someone that they need to purchase something that they don't really need . . .
On liners, they are probably a good idea, but even without one it's not like the cylinder is just going to explode or anything. If your filter does not use one, simply inspect the inside of the tube each time you change desiccant and if you see any discoloration, take action. And if you change media before it gets saturated, there will likely be no issue anyways. And if you want to use one, as already stated, simply make your own and add it in there. Not a bad idea.
On PMVs, it is important to know that desiccants will work fine at lower pressures - if you doubt it, weigh out a sample and leave it out in the open at atmospheric pressure and then weigh it again a day later. The statements that the filters "won't work" at lower pressure (thus without a PMV) are simply wrong. What is true is that in the "right situation" a PMV can increase the efficiency of a desiccant filter, and they do this through increased dwell time via reduced flow rate through the media. Multi stage air compressors basically put out a constant volume of atmospheric air regardless of output pressure, and thus the flow rate (and thus inversely the dwell time) through a given filter is higher when the pressure is lower, and lower when the pressure is higher.
So the "right situation" for needing a PMV is when filling a reservoir from empty (or at least close to it). As airgunners, we almost always fill to reservoirs that already have at least 100 bar or more in them - maybe one fill out of hundred (or less) is from empty (especially if we fill tanks from our compressors, and the tanks fill the guns). For breathing air (SCUBA and firefighting), the opposite is true - almost every fill is from close to empty, as divers try to maximise the time they have underwater with each tank (maybe not as much with fife fighters - they want to get out of the fire as soon as they can). These situations are where a PMV is highly beneficial, and should be used. Filters with PMVs are common in the dive industry. They don't hurt anything in an airgunning application, but are not beneficial or needed. If one is worried about that one in a hunder fill from low pressure, simply realize that each subsequent fill (with more fully dired air) after it will dilute out any small water vapor level that got through the first part of that initial fill - nothing much to worry aobut, unless you plan to fill the reservoir and then simply store it unused for a long time (and even that case is worlds better than the folks that fill without the use of a desiccant filter at all).
The attempt to convince airgunners that we need a PMV in their filter is purely marketing - cynically, the process of convincing someone that they need to purchase something that they don't really need . . .
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I would err on the side of caution and not drop desiccant directly into an aluminum filter body. Of course it isn’t just going to explode it will take time. The problem is there are many people that don’t know it even is a problem. I know there is no way in hades I would stand on YouTube and advise anything else. Also leaving media out in the open isn’t the same as air moving through it when forced by a compressor. Of course the media will eventually absorb from stagnant air. Flowing air doesn’t remain in the presence of the media long enough for it to work. Needs to be slowed down. Not sure on other points as I didn’t read all the post. I will listen to his advice. To each their own.A couple of thoughts on the issues of liners and PMVs . . . lots of bad info out there, much of it spread by one who refers himself an airgun scientist, but is really more of a marketing dude . . .
On liners, they are probably a good idea, but even without one it's not like the cylinder is just going to explode or anything. If your filter does not use one, simply inspect the inside of the tube each time you change desiccant and if you see any discoloration, take action. And if you change media before it gets saturated, there will likely be no issue anyways. And if you want to use one, as already stated, simply make your own and add it in there. Not a bad idea.
On PMVs, it is important to know that desiccants will work fine at lower pressures - if you doubt it, weigh out a sample and leave it out in the open at atmospheric pressure and then weigh it again a day later. The statements that the filters "won't work" at lower pressure (thus without a PMV) are simply wrong. What is true is that in the "right situation" a PMV can increase the efficiency of a desiccant filter, and they do this through increased dwell time via reduced flow rate through the media. Multi stage air compressors basically put out a constant volume of atmospheric air regardless of output pressure, and thus the flow rate (and thus inversely the dwell time) through a given filter is higher when the pressure is lower, and lower when the pressure is higher.
So the "right situation" for needing a PMV is when filling a reservoir from empty (or at least close to it). As airgunners, we almost always fill to reservoirs that already have at least 100 bar or more in them - maybe one fill out of hundred (or less) is from empty (especially if we fill tanks from our compressors, and the tanks fill the guns). For breathing air (SCUBA and firefighting), the opposite is true - almost every fill is from close to empty, as divers try to maximise the time they have underwater with each tank (maybe not as much with fife fighters - they want to get out of the fire as soon as they can). These situations are where a PMV is highly beneficial, and should be used. Filters with PMVs are common in the dive industry. They don't hurt anything in an airgunning application, but are not beneficial or needed. If one is worried about that one in a hunder fill from low pressure, simply realize that each subsequent fill (with more fully dired air) after it will dilute out any small water vapor level that got through the first part of that initial fill - nothing much to worry aobut, unless you plan to fill the reservoir and then simply store it unused for a long time (and even that case is worlds better than the folks that fill without the use of a desiccant filter at all).
The attempt to convince airgunners that we need a PMV in their filter is purely marketing - cynically, the process of convincing someone that they need to purchase something that they don't really need . . .
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Not wrong at all, check the real science from manufacturer's of breathing air compressors and filters. Check the labs that certify breathing air, research a little and don't be stupid. It is absolutely scientifically documented.
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100% of my actual hands on experience says corrosion is not present.
Believe whatever you want...
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The filter has both, charcoal and beads inside the plastic cartridge.
Easy to replace if you want to go with beads only
Easy to replace if you want to go with beads only
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The problem is contact with aluminum. The filter he is using has a barrier that I assume is made out of a metal that won’t react and cause acid production. I am sure it’s good to go
The price did go up. I ended up paying 129.
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I bought one of these last year. It does a good job, but apparently the burst disk was not as advertized, because I tried using it to fill a 6.8L bottle and the disk burst after it got over 4000 psi .... ugh. Do any of you know where I can get a new burst disk for this? thanks
https://www.amazon.com/Separator-Compressor-4500Psi-Pressure-Connector/dp/B0CYZV1KC6
https://www.amazon.com/Separator-Compressor-4500Psi-Pressure-Connector/dp/B0CYZV1KC6
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Another factor that would minimize the value of a valve holding air in the filter until a pressure like 1900 psi is the filter will be relatively cool at this point and that will tend to condense moisture from the air. As the filter heats up the air will carry more moisture but by then the valve on the gun is likely to be open which will increase dwell time.
I like the idea of a plastic cartridge for the desicant but if there is an issue with a possible reaction with aluminum (I don't know one way or the other) it would have to either also occur with aluminum oxide or be able to eat through the oxide. Aluminum actually oxidizes aggressively but the oxide doesn't flake off like steel. Another away to protect it might be to coat it. But plastic is nicely inert and seems like a better idea.
I think mine is supposed to arrive Saturday.
I like the idea of a plastic cartridge for the desicant but if there is an issue with a possible reaction with aluminum (I don't know one way or the other) it would have to either also occur with aluminum oxide or be able to eat through the oxide. Aluminum actually oxidizes aggressively but the oxide doesn't flake off like steel. Another away to protect it might be to coat it. But plastic is nicely inert and seems like a better idea.
I think mine is supposed to arrive Saturday.
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