Goldilocks Gas Struts

I think I'm the first person ever to write a blog post with the title "Goldilocks Gas Struts". Not that it's a first I really want. I've been improving the guinea pig cage to give it a "lift off roof". The problem with a cage that has doors at the front is that if your pigs have a sprightly nature (and ours do) then you can open the door and then find that the hairy monsters have made a break for freedom.

They quite enjoy the process of being caught. We don't enjoy the process of catching them.

I've fitted the hinges and the cage lid now opens rather nicely. That way we can do stuff in the cage without any risk of escaping pigs. And I quite like the god like aspect of removing their sky.

Anyhoo, next I need to find something to hold it open. It turns out that you can buy gas struts to do this thing, and they are very reasonably priced. They are calibrated in Newton's, which is interesting, but not particularly useful to me. I bought a couple of 120 Newton ones, figuring that the lid of the cage is quite heavy.

Not that heavy. I couldn't get the darned thing to shut. So I bought a pair of 60 Newton ones.

Which of course are not heavy enough. The lid won't stay open. What I need is the "Goldilocks" ones, which I think will come in at around 80 or so.....