PVC tubing rucksack frame

[Moondog55]

I need a tall external frame for a proposed project. As I can't find one locally [ ie: Australia] I'm wondering if something knocked up from PVC tubing and pipe joiners would do the job?
If anybody has made one could they please comment of strength and how well any heat shaping and moulding worked.
What did you use as the shaping mould and what did you use as the heating method> I may still have a working paint stripper gun.
25mm or 20mm pressure pipe ??
TIA

[Warin]

Heat shaping works well on electrical tubing. I have no idea how it relates to the strength of pressure pipe.. could be stronger or weaker.

[GBW]

There's also rigid heavy duty conduit (the orange stuff) available at Bunnings. It's tough but I'm not sure how the weight compares. The way to bend pvc is fill it with hot sand until it's flexy, remove the sand and shape it around a mould made from timber. There's a video on youtube making snowshoes from pvc. Should give you some ideas.

[Moondog55]

Might not need to make one.
I just found one very well used rucksack on FaceBay.
So I'll throw away the old rotten nylon pack and use the frame. Kelty not CampTrails but they are close in dimensions; just a different treatment of the above head frame extensions