UdoR wrote:
My cylinder dates 1967.
My vintage 
Hello,
In the search of portable CO detector and/or easy pulse oxymeter, I’ve found Aythre products:
pulse oxymeter fixed on headset (need a USB power):
USB-key format CO detector:
The pulse oxymeter is also linked to CO detector and can provide haptic feedback on some threshold alert. Unfortunately, they are managed also through an Iphone app..
Aithre is spelt with an “i” not a “y”
Hi All,
Just looking at two options of cylinders;
Nominal Contents volume
Y- 4.76 m3
W- 11.03 m3
Nominal Pressure at 15°C (bar) 230 bar
Cylinder being filled -
48.2 cu Ft
Max 2216 psi
How many refills am I likely to get? Not sure where to start with the maths.
I’ve just completed setting up a DYI/home refill system for my oxygen cylinder and I’ve set out the components of it below in case this is helpful for others.
I use a SkyOx system and the cylinder has a CGA-540 connection – as is common in the US.
Large oxygen cylinders in the UK are sold by BOC – I went for the “X” size initially. One borrows a cylinder (£12 inc. (VAT) per month for this size), and there is an upfront charge of £35 for a fresh cylinder. Delivery is about £85, via lorry, but you can also collect from a BOC “gas and gear” shop (but I don’t own a car so this was not practical). You also need a spindle key to open and close the valve on BOC cylinders.
To transfer oxygen from the supply cylinder to the portable bottle you need a transfiller, and this needs to fit into both cylinders. I bought this CGA-540 transfiller from Mountain High – this is their entry level product. It doesn’t have a pressure gauge for the supply cylinder (but the SkyOx cylinder comes with a gauge for that cylinder – this is important as it tells you how much is remaining and therefore how much you need to refill). I don’t think it is critical to have a gauge for the supply cylinder – it will presumably be obvious once the remaining pressure is too low to refill the portable bottle.
BOC cylinders come with a BS 341-3 socket (not CGA-540) so some sort of adapter is required: so I bought this from MH.
Once it all arrives it is fairly easy to set up – adapter screws into the BOC cylinder and then you attach the transfiller to both tanks, tightening with a spanner. Open the BOC cylinder slowly, and then open the valve on the portable cylinder, doing it slowly to ensure the bottle does not overheat. Once full, reverse the process. The TR-55 transfiller does not have a bleed valve so you have to disconnect it under pressure at the supply end only – just have to be slightly careful doing this. Detailed instructions are provided with the MH transfiller, and video instructions from MH are here: https://youtu.be/CbXmZf8NVGo?si=4xlvnvMyJAqpas1R
All in all very easy – but all this kit is not exactly cheap compared to refilling at a scuba shop (or similar) – but the advantage for me is not having to travel fairly significant distances via public transport to a suitable scuba shop.
Scuba shops are also horribly unreliable. Any sniff that it will be for aviation, you are dead in the water.
The BOC cylinder fitting is also called a BOC bullnose.
Peter wrote:
Scuba shops are also horribly unreliable. Any sniff that it will be for aviation, you are dead in the water.
That’s probably in UK; the experience across Europe is different, depending on the country.
Perfect, maybe you can sell me some :)
