What is Reddit's opinion of Pure Nitrogen Cartridges for Nitro Cold Brew Coffee - N2 Cartridge 10-Pack – For Use with Nitro Cold Brew Coffee Dispenser - Nitro Chargers for NCB Coffee, Cocktails, Tea - 2 gram Cartridges?

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It’s actually easier than you might think to make at home :p if you have a pressure cooker, or even a pressurized whipped cream canister for that matter, you can make nitro cold brewed coffee. You could even soda stream you coffee I guess? 🤔 idk if soda stream gets up to high enough pressure though. And Idk if you can get No2 cans to fit it. You can get these. Nitrogen Cartridges - N2 Cartridges Nitro by Best Whip Cartridges - Coffee Beer Cold Brew Nitro - Nitrogen Chargers - N2 Chargers (10 Pack) https://www.amazon.ca/dp/B07MZKBK6H/ref=cm_sw_r_cp_api_fabc_oviaGbP72WH31

I totally agree that pressure is dangerous, and all normal precautions should be taken. The iSi chargers result in higher pressure than other N2 carts, but lower than traditional 8g C02 or N02 so they're not really any more dangerous.

iSi chargers are listed as 2.4g of Nitrogen, versus other brands are only 2g. Theoretically at the same temperature and volume that would result in 20% higher pressure for the iSi chargers over non-iSi 2g N2 cartridges.

Given that most C02 and N02 cartridges are in the 8g size is consistent across multiple sizes of chargers (0.25L, 0.5L, 1L) ... I'm inclined to say that iSi chargers are not hazardous pressure-wise, BUT they're incompatible because they are wider than a regular 2g cartridge.

Running some quick calculations, for a 500mL whip-charger an 8g N02 or C02 cartridge would result in vessel pressure ~120-130 psi, but the 2.4g of Nitrogen would only be ~50psi (link to theory, yay PV = nRT).

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For quick comparisons it can be useful to remember that at a constant weight, a gas's pressure will be inversely proportional to its molecular weight. C02 = 44g/mol, N2 = 28g/mol. 44/28 = 1.59, so at a given weight N2 will have 59% more pressure than C02.

I have done it with these:

https://smile.amazon.com/Nitrogen-Cartridges-NITRO-Coffee-Chargers/dp/B07MZKBK6H/ref=sxts_sxwds-bia-wc-drs1_0?crid=2SJC9BT54MXIE&cv_ct_cx=n2+cartridge&dchild=1&keywords=n2+cartridge&pd_rd_i=B07MZKBK6H&pd_rd_r=54753a0a-697d-4c50-96b9-9309655b0b42&pd_rd_w=MfjTW&pd_rd_wg=9VEfC&pf_rd_p=c33e4373-edb9-47f9-a7e6-5d3d6a7a4ad0&pf_rd_r=EMV6MY0G7RYR6ZXMYQHY&psc=1&qid=1606966199&sprefix=n2+%2Caps%2C170&sr=1-1-5e875a02-02b1-4426-9916-8a5c26cd5a14

Seemed to work fine.

https://www.amazon.com/Nitrogen-Cartridges-NITRO-Coffee-Chargers/dp/B07MZKBK6H

Looks like I paid more than I thought (I bought using amazon credits I had).