There are 2 routes you can go down with making AirPort Jars. Both achieve the same objective, however the professional one looks better and has a slightly lower risk of contamination as the polyfill air filter can induce ‘Wicking’ where the mycelium can make contact with the air filter and any contaminants that are caught in the filter.
Route 1: Cheap and cheerful, requires RTV silicone and polyfill (pillow stuffing)
Route 2: More professional looking, requires Self-healing injection port, syringe filter and epoxy.
The way I worked when I first started was to find the biggest jars that will fit inside your pressure cooker, I got mine off eBay but you can get them at every hobby craft store in the country or just use old jars you have lying around.
Wide mouth jars are the best as narrow mouth jars can make getting the spawn out tricky. The best practice would be to buy them new to possible stress fractures as well as ensuring they have the silicone seal around the inner rim as seen in the photo below of the inverted lids.
Take your lids and puncture 2 holes in them, around 7mm in diameter. One in the center and one off-set is fine. You can do this using a drill, a punch set or even a pro hole puncher. Using a drill can prove messy as the thin metal of the lid will chew before it cuts, leaving a jagged edge. If you use a punch, make sure it is supported on the underside of your work surface to not bend or dent the metal.
I chose a professional metal punch from Amazon as it gives the cleanest cut, an ordinary paper punch might work too however, if I was feeling devlish, I might say order it off Amazon, use it and return it.
Take your High Temp RTV Silicone and squirt a bead around the centre point hole you’ve made. Dip your finger in water and soap and work the silicone in a circular motion until the hole is sealed up. Remove your finger upwards from the centre of the silicone, wet your finger again and press it flat so it ‘mushrooms’ out over the rim of the hole.
Once it sausages out of the backside, repeat the process so you’re creating a kind of overfilled sandwich effect, this will help prevent ripping the port through once you’ve skewered a needle through it. Make a mark on the top side of the silicone which denotes the ‘centre’ of the hole, so you don’t try to inject into the lid obscured by the silicone. Leave it to cure for 12 – 24 hours.
Next, take some polyfill and extrude it until its wispy. Then fold it back on itself and back on itself again, do this until it is a thick web of polyfill but not overly ‘tight’. Poke it through the hole with a pen or your fingers until it is half outside the lid and half inside the lid.
Cut off or pull through excess polyfill to prevent wicking and replace the polyfill as you see fit. She ain’t pretty but she is functional.
Punch your holes in the same place on the lid, making sure the outer-most hole isn’t too close to the edge of the lid as the syringe filter will overhang some-what. Next, take your high temperature epoxy, I use Gorilla Glue Epoxy and mix together the resin and hardener. You will almost defiantly knock off the syringe filter at least once, this isn’t a problem. Just re-secure it with RTV or Epoxy.
Take your syringe filter and on the barbed side (that would fit into a luer lock syringe) put a bead of epoxy on the blue rim of it. You’ll see that the top has more perforations/vents which will indicate which way up the filter should be.
Pass it through the hole and secure it against the lid of the jar by holding it firm for a few seconds and twisting slightly to remove air pockets. Then make a small bead of epoxy on the underside of the lid to prevent rusting.
Next take your self-healing injection port and put a bead of epoxy around the underside lip and push it through the central hole of the lid. Using tweezers and a tooth pick is the least messy/fiddly way of doing this.
Pass it through the hole and secure it against the lid of the jar by holding it firm for a few seconds and twisting slightly to remove air pockets.
I know which one i’d put on a Christmas card that’s for sure. There are other ways of making jars, some use Tyvek or permeable gaskets but all achieve the same end. I prefer the ‘pro’ lids because they require less maintenance as every now and then you need to replace the polyfill or re-set the ports, the epoxy makes these lids pretty permanent. The cost difference is practically negligible, in my experience if you’re running more than 30 jars at once you should be looking to upgrade to bags.
Archer’s Mushrooms Store
Hi!
Couldnt you just use one port only? In this case the syringe filter.. then you could use this to inoculate the lc (and does it also serve for gas exchange?).
King regards
Ian
Hi Ian!
The syringe filters purpose is just that. In the medical field it’s used to remove particles from samples like any filter. If you were to use a Syringe filter to inoculate, you would likely filter out much of the mycelium and block up the port but also introduce a good avenue for contamination to ‘wick’ through if that makes sense. Once used as an actual filter, it’s gas exchange ability would be reduced severely as it would be gunked up with mycelium.
Some people do just use one port, using polyfil, and just inject straight through that with a needle. I’ve never done this but as long as the fundamental principles of sterile working are followed, I can’t see a reason that it wouldn’t work! Hope that helped!
All the best,
Gareth
Hey Gareth,
For jars you won’t inoculate with a syringe (a2g, g2g) could just use the syringe filter right? It’s for gas exchange?
Thanks
Hi Paul,
don’t inject through the syringe filter inject through a rubber injection port!
Hope that helps!
“For jars you won’t inoculate with a syringe”
Why is the syringe filler upside down ?
Is it only for an air vent and no you extract culture through injection port
Hi Richard,
They’re not handed so they work either way for gas exchange! It’s only for air, you wouldn’t extract through because it would clog up with mycelium and need replacing! Correct, you draw through the injection port.
All the best,
Gareth
can we reuse this lid multiple times
Hi mate,
You can. The filter will need replacing eventually but if you look after it and don’t let anything grow/boil through it, it should last a good few runs!
All the best,
Gareth
How do you clean the lid with the filter on it? Won’t it get wet and cause contamination?
Hi mate – You replace them periodically or when they require changing. Moisture isn’t an issue as it drys out!
Can you just put the jars with the syringe filters and self healing ports into a pressure cooker? Or would it melt the plastic/rubber?
Thanks!
Hi mate – They’re perfectly suitable for the PC!
All the best!
Gareth
When you say 7mm, you really mean 7cm?
Hi mate 7mm is correct for the ports and filters!
Cheers,
Gareth
Thanks gareth, i suffer from depression and am going to try and culminate my own medicine after trying years an years on the doctors advice to no prevail. Much appreciate the info
Hope you can start to feel better soon Brad!
Take care!
Gareth