Re: O Rings vs swell sealing
Posted: Mon Jun 10, 2013 11:30 am
It does sound interesting. Do you have a picture of it?
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bugwubber wrote:It does sound interesting. Do you have a picture of it?
US pvc pipe is nominally sized. 1/2" pvc is actually .60andy_R wrote:What are the exact specs on the 3/8 and 1/2 inch pipe - here in the UK we use metric, so I want to order the right stuff from the states. The materiels will be cheap, but shipping won't, so I want to order the right stuff first time! Are there particular suppliers that you recommend?
I know the OD required for the outer pipe, its the ID of the outer pipe and the OD of the inner pipe in the "o-ring" design that I need as these parts aren't readily available in the UKbugwubber wrote:US pvc pipe is nominally sized. 1/2" pvc is actually .60andy_R wrote:What are the exact specs on the 3/8 and 1/2 inch pipe - here in the UK we use metric, so I want to order the right stuff from the states. The materiels will be cheap, but shipping won't, so I want to order the right stuff first time! Are there particular suppliers that you recommend?
" (15.26mm) inside diameter. What counts is outside diameter which is .84" or 21.4 mm. Carbonated beverage Bottles usually have an inside diameter of .85" or 21.5mm.
Best thing to do is to visit your local hardware store with a bottle or at least a bottle nozzle in hand and try to fit it over the various pipes.
Oh ok got it. The funny thing is both pipes are called 1/2" here. The larger is Schedule 40, the smaller is Copper Tube Size.andy_R wrote:I know the OD required for the outer pipe, its the ID of the outer pipe and the OD of the inner pipe in the "o-ring" design that I need as these parts aren't readily available in the UKbugwubber wrote:US pvc pipe is nominally sized. 1/2" pvc is actually .60andy_R wrote:What are the exact specs on the 3/8 and 1/2 inch pipe - here in the UK we use metric, so I want to order the right stuff from the states. The materiels will be cheap, but shipping won't, so I want to order the right stuff first time! Are there particular suppliers that you recommend?
" (15.26mm) inside diameter. What counts is outside diameter which is .84" or 21.4 mm. Carbonated beverage Bottles usually have an inside diameter of .85" or 21.5mm.
Best thing to do is to visit your local hardware store with a bottle or at least a bottle nozzle in hand and try to fit it over the various pipes.
We have made launchers using 1/2" Copper pipe as the inside tube of our o-ring design. It does not quite fit because the OD of the copper is a tiny bit bigger than the ID of the PVC, but some coarse sandpaper is all that was needed to make the ID of the PVC large enough to fit the copper pipe. We had to use PL premium to glue them together, since the PVC cement will not work on the copper pipe.andy_R wrote:Sooo....an idea occured to me. As we can't get the same size pipes over here in the uk very readily, I decided to do some "fettling". A length of 1/2" class E PVC pipe from a specialist hot tub/garden aquatics supplier that has an O.D. of 21.5mm and an I.D. of 17.2mm. Take a length of 21.5mm floplast waste pipe and make an axial cut about 13mm wide. This will now fit snugly inside the 1/2pvc pipe. Inset a lenght of 15mm copper tube into sleeve and pipe. Perfect fit. Remove one of the the o-rings from a 15mm pvc pushfit coupling and slide it onto the copper pipe. Test fit in the neck of a 2ltr pop bottle. Perfect fit. More to follow, hopefully with pics....