High Pressure Filter

Guys,

Here's what I bought for my Daystate LC110 based on @humdinger advice. Works GREAT!!!

@humdinger response to my post:

You should add a high pressure filter. The least expensive way is to order one from Aliexpress.com. Here is a link:
https://www.aliexpress.com/item/water-oil-separator-absord-moisture-absord-water-for-dry-and-clean-high-pressure-air/32827947479.html?spm=a2g0s.8937460.0.0.FaZVwFYou can cut the tampon that comes with the filter into 1” sections and use them as end caps. Fill the space with zeolite 13x desiccant. You can buy it on ebay.
Here’s the link:https://www.ebay.com/itm/3-lbs-Molecular-Zeolite-Beads-Type-13X/312090493908?epid=862892059&hash=item48aa0b03d4:g:w4gAAOSwo6lWFpeYThis zeolite can be recharged in a flat pan in an oven at 400 degrees for an hour and reused many times. This will last you a lifetime. The filter only needs to be 
recharged about every 10 hours of compressor run time. The gold filter from Aliexpress takes about 2 weeks from ordering to arrival. For an investment of $85, you can save a bunch. The gold filter is identical to the Diablo filter that AofA sells for $189. It has less bells and whistles but does the same filtration as the $400 alpha filter.Your compressor water tower bleeds off most of the moisture but a final filter catches the last 1%. Don’t worry about filling your tank once or twice before you add the filter. The water separator does most of the work but this is the last bit of insurance. That is a great compressor for the money.
 
The only thing I would add is to make sure you get some (about an inch) compression when you assemble the filter with tampon ends and Zeolite. I usually insert the first piece of tampon, then fill enough so that when I add the second piece of tampon the level of the tampon is right at the start of the inner threads for the cap (cut the cotton tampon that comes with the filter into 1 to 1 1/2 inch sections). That way when you screw in the end cap, it compresses the cotton tampons and Zeolite. The "gold" filter that has the hole drilled on each end cap that allows you to easily loosen and tighten the caps makes it easier than the ones that the end caps are just knurles and you have to use a plastic jawed plyers or vice grips to loosen or tighten. With the hole you just insert a rod or phillips screwdriver and its much easier... I also recommend based on Thurmond (@T3PRanch) to "salt" some color changing silica beads (a very small amount) in with the Zeolite so that you can easily check if its absorbed enough moisture that it needs to be changed out.
 
I recharged my "small"Omega bottle with my Yong Heng without the AliExpress gold filter and Zeolite molecular sieve. It was at 3000 psi, and I brought it up to 4500 psi. After recharging my PCP with this new supply of air, when I vented the small line connecting the tank to my PCP, I noticed a strange, "stinky" smell. I'm looking forward to setting up my gold filter and getting some dry, clean air into that tank! UPS tells me that my goodies frpm AliExpress will arrive Friday 5/18.
 
Will do Centercut. Mine came with a male foster on one end and the caps are cut to accept a large open end wrench. The hose is threaded to go into the opposite end with another foster. Oh I ordered May 4th so arrival was reasonable. I will order new micro hoses, several of us that bought CGA or Din fill stations from China had them fail.
You guys thinking on going down this compressor road? Centercut has probably done more and understands these better than most. I encourage you to do a search pretty interesting stuff. I don't have his and a lot of guys skill sets on here, sooooo that compressor is going to cost me way more money! LOL

Dennis
 
@eaglebeak, maybe you and Thurmond told me at the same time? I don’t really remember but it’s a good idea so thanks! And the link is the best deal on a gold filter plus it has the ends with thru hole that work best! Nice!!!
@2d1c, if I had to buy one right now I’d get the $1895 Daystate 115vac “used like new” deal they currently have at AoA. It’s a Coltri and will last forever with an annual oil change. I’d still use the “gold” filter...
Mike 
 
"Centercut"@eaglebeak, maybe you and Thurmond told me at the same time? I don’t really remember but it’s a good idea so thanks! And the link is the best deal on a gold filter plus it has the ends with thru hole that work best! Nice!!!
@2d1c, if I had to buy one right now I’d get the $1895 Daystate 115vac “used like new” deal they currently have at AoA. It’s a Coltri and will last forever with an annual oil change. I’d still use the “gold” filter...
Mike
@ Centercut. No sweat Mike. The unit in the link I provided is the cheapest one I could find with free shipping. The one that I'm using is the Tuxing branded one with the flat spanner cutouts in the caps. I got mine on eBay as I was and still are having issues with Aliexpress. I paid slightly more for mine because there was a small shipping fee. As far as I can see, there is no difference between mine and the one in the link apart from the Tommy bar holes in the end caps. The filters and O-rings are interchangeable. I have even seen ads that show caps with both features. I have made up a smaller one from a different maker that has two small fiber filters and leaves enough space for a small amount of desiccant. I have this in case I just want to top of a gun directly from the pump or booster without having to pressurize that large gold one. It takes the Altaros 20 minutes just to prime the gold filter before I can start filling tank or gun. It is also useful, for hand pumping Here is the link if anybody is interested. https://www.aliexpress.com/item/High-pressure-PCP-hand-pump-air-filter-Oil-water-Separator-For-High-Pressure-pcp-4500psi-30mpa/1000005070567.html?spm=2114.10010108.1000014.30.4ae23e46PLN2KB&scm=1007.13338.98644.000000000000000&scm_id=1007.13338.98644.000000000000000&scm-url=1007.13338.98644.000000000000000&pvid=780313da-1aaa-43ba-9b74-6ac7ffa5310c&_t=pvid:780313da-1aaa-43ba-9b74-6ac7ffa5310c,scm-url:1007.13338.98644.000000000000000
 
"txrpls"From what I have gleaned from all the threads on this for the molecular sieve to be effective you need to install a pressure maintaining valve. I have all the parts ordered to install one on my machine. It will hold pressure in the filter until 1800psi (default) and then allow it to go through.
Sounds like more spin from J.B. How often do you fill from empty? Low-pressure air is not going to pass through your filter into a pressurized tank or gun until it is higher than the vessel that you are filling. Some of the information floating around is not only bogus but downright ridiculous.
 
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Personally, I wouldn’t buy squat from JB, but this guy made sense;

LOL ... you guys are making this too hard. Who cares what the dew point is as long as you are doing your best to remove as much moisture as you can?

ANY compressor is going to be able to compress the air. And, since water or oil isn't compressible, it becomes a bigger "chunk" of the air that gets pumped out. So, to get air out, we put a gizmo inline that makes the air change direction a LOT which makes the uncompressed chunk of moisture fall free from the air flow. There are two things that can increase the amount of moisture that is knocked free.
1. Increase the air flow - the faster the air is flowing across the deflectors, the more moisture is going to get knocked loose.
2. Increase air density - the thicker the air is before going into the separator, the easier the moisture will come loose

Once you have purchased your compressor, you are pretty much locked in to the air flow rate so nothing you can do for #1. But changing #2 is easy ... install a pressure maintaining valve. A simple PMV will restrict the air flow until pressure gets up to about 1800 psi. 

To further process air, we add a filter chamber that is filled with a real fine filter medium called molecular sieve. Basically, they are little balls of material that has micro pores that trap moisture molecules that get past the moisture separator. To increase the efficiency of THIS filter we need to:
1. Increase the dwell time - this allows the air to spend more time flowing across the media, increasing the chance of moisture getting trapped 
2. Increase air density - denser air means the moisture chunk sticks in the media better

So, assuming you don't have an adjustable size filter tower, the only other adjustment you can add is a PMV.

So ... this is really a no brainer ... install one PMV on the outlet of your filter so that it can maintain back pressure on the entire filtration system.


Every scuba compressor I looked at has a PMV before the outlet. I’m putting mine on the top of the Chinese filter. It cost $80 plus a few $ in fittings. Not much money for piece of mind imo...
 
If 1800 psi is the magic pressure for this stuff to work, then why not just refill when your bottle gets down to that. I asked the supplier about reactivating the stuff in the oven. He told me that it was not possible because by the time it cools down it will be partly saturated again. That is why they need special equipment to activate the stuff and it is sold and stored in a vacuum. It may work better under high-pressure but it will still work under low pressure. Adding a PMV will have zero effect on the dwell time when the filter pressure is the same as the tank pressure. The thread that you a quoting from is technical jargon that is more directed towards the scuba industry that requires bottles to be filled from almost empty every time. If you want to waste 80 bucks, knock your socks off.
 
Aaaarrrrggghhhh! A PMV is critical if you are routinely filling SCUBA tanks from EMPTY! Do we as air gunners run our HP air tanks to empty? Nope. Maybe from 4500 down to 3000 psi. Maybe even a little less? But never down to 2000 psi or less unless you’re emptying the tank for some other reason. So why in the world do you need a device to maintain pressure at 1800 psi when we never go that low in the first place? Let’s use common sense here people. If your tank is at 3000 psi, and you start your compressor with tank valve shut, you quickly build up pressure until it is close to tank pressure then you open tank valve and fill to 4500 psi. So what exactly did the PMV do for you? I’ll answer that - nothing. Not a damn thing. Nada. Zilch. So a PMV for SCUBA divers makes sense because they take their tanks very low in pressure. But we airgunners don’t do that. I take my tanks down to 3000 to 3200 psi and then top them off. So hopefully all of us can see that a PMV is pretty much useless for an air gunner. Nuff said, drops the mic...
 
That's my point. Most of us top up our bottles at no less than 200 bar. Even if you are using a 200 bar scuba bottle with a discovery or something that only fills to 2000 psi, you will still be topping up before reaching 1800. I saw this discussion last time it was raised but kept out of it because people like yourself explained the futility of this argument, well enough.