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O Ring sealing using UK products

Discussion about Compressors, hose, pipes, fittings, launchers, release mechanisms, and launch tubes.
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andy_R
New Member
Posts: 8
Joined: Mon Jul 21, 2014 1:32 pm

O Ring sealing using UK products

Post by andy_R » Mon Sep 29, 2014 10:38 am

As mentioned on a previous thread, I've had problems sourcing materials specified in US sizes - they just aren't available here in the UK.
However, I've come up with a workaround that works really well.

You will need:

15mm copper pipe (B&Q)
1/2 Inch Class E PVC pipe (I got mine here https://www.colglo.co.uk/product.php?product=PVCTI3013)
21.5mm Waste pipe (B&Q)
15mm pushfit coupling (B&Q)
21.5mm coupling for waste pipe (B&Q)
15mm copper solder ring coupling

All of the pictures here, are taken of the launcher in a partiall disassembled state, as it can be stripped down and repaired in moments if needs be. I forgot to take photos during the initial build as I got into a bit of a building frenzy so you will see components already in place that arent mentioned - cable tie launcher and check valve etc.
Start by cutting 2 lengths of copper pipe - 1 approx 350mm, the other as long as you wish. Join them back together with the solder ring coupling
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Next, cut 2 short lengths of your 1/2 inch pvc pipe - length doesnt really matter, as slong as they protrude at least 1cm when fully inserted into the 21.5mm coupling. You will also need to cut a length of the 21.5mm waste pipe approx the same length as one of your pieces of pvc pipe. This then needs to be cut along it's length and about 13mm removed so it can be rolled into the pvc pipe. Assemble as shown and then insert copper pipe.
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You can see thet the bottom piece of pvc slides over the lip of the 15mm copper coupling and snugs up to the swelling of the solder ring
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Now grab your 15mm push fit connector and open it up. You're after the big fat O Ring that's in there (there are 2 so you get a spare too!) Slide it into place on your copper tube.
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Next, cut a length of 1/2 PVC pipe approx 310mm and 2 pieces of 21.5mm waste pipe approx 40mm long. Cut the waste pipe along it's length, as last time, and glue into the PVC pipe. It doesn't matter if there is a gap between the edges of the waste pipe when it is inserted in the PVC pipe as this is functioning as a sleeve - the copper pipe is pressurised and the ring is providing the seal between the copper pipe and the bottle neck.
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Insert the copper pipe and slide the PVC tube down the pipe until it's a couple of mm from the O ring.
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I used a standard Clark Cable tie launching system and attach the whole gubbins my "go to" launch pad. I stuck a bottle on it this morning at 70PSI and 4 hours later it's still got pressure in it.
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