Okay, I'll do that now. It's half 12 in the morning so I wont be able to test anything for a good 10 hours unfortunately.

Yeah, Crowley is right, my valve doesn't have the circular opening, there was electrical tape over the rectangular one as a test to see if it would help rather than the more permanent epoxy option.

I'm pretty sure the blowgun is sealed, the only place I can hear a leak is at the output of the sprinkler so hey.

Black bleed screw is indeed epoxy'd, metal tube isn't epoxied and my blow gun is connected, fully sealed just backwards, if that's a problem I could change it but it'd be a big hassle.

My blow gun isn't threaded in. It had an attachment with it that fit perfectly onto a really small hose nipple I had and so I epoxied them together to avoid buying a double threaded nipple. I'll have to try it again later as I tested the valve using a 2L drinks bottle, dont worry it was perfectly se...

I was using a double cylinder foot pump, pics on the way. Edit for the pictures. https://www.dropbox.com/s/mdkokg5594itiyj/2012-08-24%2021.54.17.jpg Electrical tape over the rectangular slit that leads to the tiny pipe in the chamber. https://www.dropbox.com/s/jdy3c2yyfm0b6wa/2012-08-24%2021.54.43.j...

Nope, I just came back to post saying that no matter what there's a fair amount of air going through it, tried blocking the hole and the little pipe in the chamber. There is a massive difference between when the blowgun's open and not as far as volume getting through is concerned but there's so much...

My sprinkler valve's solenoid was in the middle so i just re-purposed the hole to fit the blow gun

The blowgun hole is sealed shut with a lot of epoxy, the whole area, thanks guys, guess I'll have to wait for my parts to come in the post tomorrow and then finish gluing to test it.

I bought a 1" orbit sprinkler valve and modded it as per the guide that's on the GGDT website. However when I have my valve fully set up ready to be used I try blowing through the in hole and it just goes through no matter what state the blowgun is in. The spring is in place, also in the last pictur...

The postage isn't that bad here but the pipe is just more expensive and VAT is just the icing on the overpriced, proverbial cake hahaha.

This is so much more expensive than it seems to be in the US, it's coming up towards £100 for the whole thing where as most people call spud guns a "60-70 dollar" project.

Am I doing something wrong?

Thanks, I've pieced myself an order together that has 4x the amount of pipe for about £20 more as well as all the cleaner and cement. Should have a cannon in the next month.

I'm buying some pressure rated PVC from http://www.koicarp.net/ but they only sell "Pond Friendly" adhesives and don't seem to have the usual type of PVC cement. It was a very large effort just to find that place which actually sells reasonable lengths of decent pipe as well as all the fittings need...

I have a bottle of rubbing alcohol/Isopropanol that's 99%, will that do?