Cheap Compressor Filters

[iain/hsm]

Satisfying Curiosity...But Killed the Cat

There fixed that too

NO curiosity is no way close enough a reason to consider this tat let alone to shell out and buy it.

You dont have to enact curiosity in order to be informed of the low hydraulic burst pressure for the shell
You dont need curiosity to know the design life pressure cycles are too low for comfort
You dont need curiosity to know the vessel design code is some junked up China special export code
You dont need curiosity to know if the shell fails safe on corroision by leaking or by catastrophic failure
when parts start flying about the place

- Isn't THAT enough of a reason to discard this item as cheap tat from China. Discuss that on the forum?
- There are no fun points in discussing an avocated risk.

1. Surprising comparisons to the old systems

Used to be know as a Chinese copy. In other words inferior tat

2. Breathing Air Test Results... Once I set these filters up, I plan to get the air tested. Anybody interested in that?

Why? shouldnt the manufacturer have done that for you if it was fit for purpose

3. Aluminum Filter Tube Life... Most compressor companies recommend replacing aluminum tube filters after so much use. Are these of comparable life?

No for the reason I gave earlier.
Now if you have an accurate OD and ID and length for the shell and end plugs lengths together with a PMI hit of the shell and a Vickers, Rockwell or Brinell hardness number in the top edge you can get a rough idea of the predicted MTBF but the threads will rot out the soft aluminium well before that and the poor anodizing will rot out the shell seal area.

4. More?

I hope not, no cat has been killed yet

 

[SurfLung]

Update...
- I've ordered adaptors for G1/4 to 1/4 npt. If I ordered the right ones, I should be on more familiar ground with hooking up the plumbing.
- I'll be away from my computer a week or so but will certainly post my results when I get back.

 

[W W Meixner]

Cheap Compressor Filters...
- I've seen these advertised on Ebay and it tweaked my curiosity. I wanted to see for myself:
1. Are they compatible with Lawrence Factor pre-packed filters?
2. Is the moisture condenser tower of decent design/function?
3. Are the towers robust enough for high pressure?
4. So I ordered a set to see for myself.
View attachment 561891

Lawrence Factor Compatibility...
- The closest thing I found is the Lawrence Factor 15XXX series that fit Coltri MCH-6 filter towers. These are same diameter but a little too long. I think the LF filter tube can be shortened into a convenient re-packable tube that would fit. On the other hand, the filter that comes with could also be re-packed. There's a difference in the two filters at the O-ring seal. Personally, I would want the filter to be about 2/3rds 13X Sieve and 1/3 carbon.
(Below: Lawrence Factor is on the left)
View attachment 561892
View attachment 561893

Moisture Condenser Tower...
- I am particularly interested in the moisture condenser design because I had to make one for my old Coltri MCH-6 and my old Tornado Kidde actually uses aquarium rocks for condensation surface area. I don't know if this design is unique but it looks better than what was in my old MCH-6 as well as what's in the new MaxAir 35. It looks like it keeps incoming condensation better separated from outgoing dry air.
View attachment 561894
View attachment 561895

Robust Design/Construction
- The specs say these filtertowers are rated to 300 BAR or 4351 psi.
- They are thick aluminum construction and heavy.
- Dimensionally they are comparable to the MaxAir 35 and Coltri MCH-6 filter towers.
View attachment 561896

Additional Thoughts/Comments...
- My challenge right now in trying these out is that they have input and output threads of G1/4. I have other plumbing to hook up and will need these to be adapted to 1/4 NPT for pressure switch, OPV, PMV, etc.
- The all carbon filter they come with isn't that shocking... It wasn't all that long ago that MCH-6 filters were all carbon. Some of the other Ebay filters are being offered in 3-part filter materials so I would not be surprised if these get offered that way too.
- Meantime I can either shorten Lawrence factor before use or re-pack.
- These filters have a clever extraction method... The tops are threaded for a bolt. Screw it in and you have a nice big handle to pull out the filter.

SL...

Why Cheap...what's your compressor...and the quality of your breathing gas worth to you...puts me in mind of computer owners/rebreather owners looking for cheap batteries...

Although I'm sure there are exceptions...but if it's listed on Grey-Bay...if it's far less expensive than it should be...and it's covered with Chinese writing...that should be your ''walk away'' notification...

W.W...

 

[SurfLung]

Adaptors Came in This Week While I was Away...

- I'll let you know how they work out when I get a chance to try them.

 

[2airishuman]

1. Threads in side wall corrode out in < 6 months
2. Aluminium body poor thin film decorative dye anodizing corrosion internal wall
3. Thread form neither BSP or NPT or JIS when measured with go/no go gauge
4. Not manufactured to any recognized known pressure rating standard
5. OD to ID extra heavy wall thickness suggests they use a low quality aluminium
6. Taper metal threads are cadmium plated OK for air gun (see cadmium poisoning)
7. Milling flats to side wall shell for side fittings reduces allowable working pressure
8. Ebay sellers no liability buyer beware
9. Frankly why we are taking this crap seriously on this forum is beyond me
10. Misleading misinformed air gun tat for the misguided with no place in this forum.

Iain,

How much of that do you actually know? Did you test the threads with a gauge? Did you swab the threads for cadmium? Do you have evidence to suggest that the presence of cadmium plating on the threads will lead to high enough cadmium levels in the output air to pose a hazard?

OSHA Guide: Cadmium

I share your concerns about the safety and cycle life of the pressure vessel but find that some of your other comments fail to move the discussion forward.

 

[iain/hsm]

Iain,

How much of that do you actually know? Did you test the threads with a gauge? Did you swab the threads for cadmium? Do you have evidence to suggest that the presence of cadmium plating on the threads will lead to high enough cadmium levels in the output air to pose a hazard?

OSHA Guide: Cadmium

I share your concerns about the safety and cycle life of the pressure vessel but find that some of your other comments fail to move the discussion forward.

Thank you for your concern.
For an air gun application I really like the idea of cadmium plating especially in parts in contact with aluminum, just not in breathing gas applications. Alternatively if I don’t use it then I don’t need to worry what’s going to happen or any health implication even should I decide to lick the coating off with my tongue every day for the next 10 years in gratitude to China for making such a splendid product.

The thread gauge is more interesting, and your right I dont know much but I know what it isnt after tested with both a NPT and NGT stepped thread plug gauge also a standard UK BSPT taper. Now I do understand the differences and the fact that the filter in question had the fitting removed by others prior to the gauge test that may have had an effect on the original thread with the elbow fitting being turned to both seal and for the elbow to position correctly must have adding additional stress or strain to the soft aluminium. At first was thought NPT was the nearest thread,

The alternative NGT thread gauge was used to test if the 3 thread additional minimum effective length difference than the standard NPT made any difference.Granted the test gauges were different in tolerance one was to ANSI B1 and the NGT gauge was to ANSI CGA V1 but the thread being tested fully matched non.
Now I also understand that it is possible that they are manufactured to another thread form ANSI CGA V1 CSAB96 or ANSI B57-1 even to the old NGO thread form but as we don’t have those gauges to test with I cant be certain. Hence the BSPT thread was thought. Again it is possible that they made it to a modified 55 degree Whitworth form, Or with some degree of truncation or with some older or class of ISO 228 G standard. Class A or B was another consideration.

So in conclusion this is a product for cheapskate air gunners who are not going to know or care one thread from another. And on a scale of importance if the customer don’t care why should a manufacturer in China.
Its not like your going to catch a cold with it. So your right I dont know much, I only know what it isnt. LOL

 

[SurfLung]

JIC Adaptors...

- I found the simplest solution for me to hook up this filter array and try it out... JIC Adaptors. I bought two adaptors that convert 1/4 BSP to JIC 4 (or AN4). They fit and seal perfectly. All I have to do is connect my Fill whip to the OUT port and my regular JIC equipped output hose to the IN port.
1. My fill whip has a JIC 4 connector plus a back pressure regulator (BPR), pressure gauge, and bleed valve.
2. The JIC 4 inlet connection is common to most compressors... Including my RIX SA3... Which also has a BPR (so plenty of check valves).
3. In other words, it's ready for a trial run if I use my RIX SA3 compressor... So that's what I'll do tonight after work.

Thoughts and Considerations:
1. I like the moisture condensation tube design. It's definitely more sophisticated than the old Tornado Kidde condenser (with aquarium rocks for surface area). It's also an improvement over the original screen dissipator system on my old (1980s) Aerotecnica MCH-6. It works somewhat like the condenser on my old OLMEVA 6000 filter array but different. It is not as sophisticated as the condensers on the RIX SA3... But its certainly a well thought out design
2. On the other hand, I'm not so sure the FILTER tube is of sufficient capacity. Certainly if the filter is small, you have to change it more often. But in another discussion about my old Aerotecnica MCH_6 filters, someone mentioned "dwell time" of air moving through the one single filter tube. Of course this speaks to the fill rate of the compressor. And maybe 3-4 cfm gets sufficient dwell time with just the one filter tube. I'm pretty sure I can adapt Lawrence Factor filters to work in this filter tube.

 

[SurfLung]

- Last night, I hooked up the Chinese filter array from my RIX at the BPR, to the filter array, and then to my BPR equipped fill whip. So, I ran the filters up to 1800 psi and filled the little 38 cf test tank up to 2000 psi. So much for a simple function test... It all worked fine.

- Unfortunately, the RIX already has two moisture condensing towers so there probably wasn't alot left in the air for the new filter array condenser. I DID feel SOME moisture when I opened the drain on it. But in hindsight, I really didn't end up testing much other than the connections and the fact that it didn't blow up (as expected by some).

- Next time I will run it directly off the Tornado/Kidde 3000 compressor which should at least give a good test of the moisture condenser tube.

 

[rhwestfall]

Glad you are still with us...

 

[SurfLung]

This Will Be All For Awhile...

- After an earlier run, I discovered considerable condensation in the hose coming down from the filter array... The moisture had pooled above the check valve and everything below the check valve got blown out by the auto drain. So this time I put the check valve up near the filter array and connected directly to the compressor outlet. So, the hose leading up to the filter array condenses a fair amount of moisture that runs back down the hose. On my RIX compressor system, I installed a bleed valve at the bottom and I am able to drain this hose condensation. On the Tornado Kidde, I can just use the auto drain function to blast out the hose moisture... I believe this is pretty close to the way I will eventually plumb the Tornado/Kidde.
- As for the effectiveness of the Cheap Filter Array, I have some comments/conclusions...

1. I never did see any significant moisture accumulate in the moisture condenser... At least not enough to see it physically drain from the bleed valve. This could be due to the way I tested it, however. Once by using my RIX which already drained significant moisture before the air got to this filter array. A second time I ran directly from the Tornado/Kidde so that the cheap filter array should have been the primary moisture accumulator. Again, after filling a 42 cf tank, I did not see enough moisture accumulate to physically see it drain from the bleed valve... BUT, a significant amount DID condense in the hose below it (as described above).

2. The Filter media tube is more of a project than I feel like pursuing. The Lawrence factor filters are similar in size but not a correct fit... I think the original filter that comes with this set could be re-packed with 13X Sieve and activated charcoal. But it wouldn't have that nice blue test strip like the Lawrence Factor filters.

3. Overall, it looks like this "Cheap Compressor Filter" system could be made to work but, for all of the extra effort to make it so, I think I could get a ready to go condenser and filter system from Jim Shelden or just use the same filters as I have for my RIX compressor.

4. Finally, On my last run I developed an oil leak on the Tornado/Kidde compressor. I'm going to have to track that down and fix it... Hopefully just a loose connection. But I think by the time I get that chased down, I'm going to want to quit experimenting, and hook this Tornado/Kidde up to a filter system that's already proven reliable and effective.