Mixing stik project.....

[Hoosier]

I have a couple of questions on the Mixing stik.



1. It is possible to use “plastic barb” instead of the “Brass barb.” I thought the inlet pressure of “He and O2” wouldn’t be high, so the plastic barb can handle it. Did I underestimate the inlet pressure?

This is the Pre-mixing stik for He and O2.

2. The pre-mixing sitk is made of ½ PVC pipe. What is the best baffle for this tiny diameter pipe? I am thinking of using a “nickel.”

3. As for the oxygen sensor, Oxycheq DIY analyzer is almost “bible” in this project. How about Miniox oxygen analyzer plus sensor? Is it accurate and easy to get the sensor replacement? It has been pre-built unlike Oxycheq one.

4. After assembling completely, should it be PVC cemented?



Thanks in advance,

 

[pescador775]

Hi,
Plastic components like the inlet barb are fine. Glue is not really necessary as the pvc fittings usually make a tight joint. Sometimes, one might wish to disassemble for some reason. The Miniox is a beautiful detector, built to medical criteria. I like the alarms on the Miniox III, etc but might not work right with a prestik. Reason, O2 levels might be lower than 18%, the limit for the alarm low end. The Oxychek is good, too. Small plastic disks with small holes should be OK for baffles. Make the holes random, place two disks within 1/4 inch of each other, use a series of these paired arrangements. Personally, I would just stuff the bore with a wad of stainless steel pad. Stretch the thing out and use a stick to force inside. There is a concern that stainless fibers could enter the compressor. This will not happen if the output goes into the compressor intake filter. The filter will stop any particles, etc. My stiks are larger in diameter and use these pads. I insert a homemade filter pad in the bottom. This is made from packing foam, the type that is in some seat cushions, etc. There are different ways to secure this pad. I make a spring from a hose clamp. Cut off the screw and wind the stainless band into a spring and insert into the stik below the foam filter.

 

[pescador775]

Sensors are available from Oxycheq. RC Dive Technology was my preferred supplier but they are out of business, shame.

 

[Hoosier]

Hi,
Plastic components like the inlet barb are fine. Glue is not really necessary as the pvc fittings usually make a tight joint. Sometimes, one might wish to disassemble for some reason. The Miniox is a beautiful detector, built to medical criteria. I like the alarms on the Miniox III, etc but might not work right with a prestik. Reason, O2 levels might be lower than 18%, the limit for the alarm low end. The Oxychek is good, too. Small plastic disks with small holes should be OK for baffles. Make the holes random, place two disks within 1/4 inch of each other, use a series of these paired arrangements. Personally, I would just stuff the bore with a wad of stainless steel pad. Stretch the thing out and use a stick to force inside. There is a concern that stainless fibers could enter the compressor. This will not happen if the output goes into the compressor intake filter. The filter will stop any particles, etc. My stiks are larger in diameter and use these pads. I insert a homemade filter pad in the bottom. This is made from packing foam, the type that is in some seat cushions, etc. There are different ways to secure this pad. I make a spring from a hose clamp. Cut off the screw and wind the stainless band into a spring and insert into the stik below the foam filter.

Thank you so much for your post.....

If you don't mind, I have a question about hyper filter. I was offered that 32 inch hyperfilter is about $1200. I also got another offer, the unknown named hyper filter stack $800 locally. However, after digging out some info on the web, I found that the filter chamber is only $575 from here.

If I get the right filter fitted for that chamber, what else do I need to get for the hyper filter assemble? It seems like the picture only shows the chamber itself.

I also found that there is a huge price difference depending on the length and brand name, such as LF hyper filter (http://www.purification-supplies.com/images/hf962134f.htm). Is there a real difference for an actual purifying job?

Thanks in advance,

 

[pescador775]

A hyper filter is just an aluminum pipe with perhaps a micronic separator and large canister inside. Like all filtration systems, they must operate in series with a backpressure valve. Normally, a compressor comes equipped with this valve. Get the cheapest one. Before buying, inquire about the micronic element. It would be unusual if one is not installed on the output of the canister or, alternately, the filter cartridge but, if not, and if you elect to buy the filter canister, it will be necessary to buy an inline micronic filter from Compressed Air Specialties or Lawrence Factor. The purpose of this device is to prevent carbon dust from being pumped into the Scuba tank.