Heaven help me - I've just bought a delta kit :-)

[curious aardvark]

Ah I am in the same country so that really helps.

I did see some cheap pei on amazon (or ebay) - £9 for 200x200 square. You'd have to trim it, but be interesting to see what the differences are.
https://www.ebay.com/sch/i.html?_odk..._sacat=183062a

Having some bloody annoying issues at the moment.

Got a mould to print and ship.
Made lots in the past. At the moment the last 3 have had a slanted top. Sides are straight and the moulds would probably work - but I'm selling these and they need to be right.
I can see more or less what's happening. About the 1/3 mark it looks like a layer slides sideways and creates the slant. Which sort of travels up the model as it prints and results in the uneven top. The sides are perfectly straight - it's really odd.
Doesn't look like anything up with the carriages, as that would produce a different effect.

Just printed a tall cylinder and tall cube - both absolutely fine. Both taller than the moulds and no sign of any issue. So it's not something that happens at a specific height.
I've generated the stl file a few times and it previews perfectly.
Printed a some small pieces out - perfect.

Now, I do rotate the models to put the retraction point at the bottom corner where it can't effect anything.
So I'm now trying one without rotation and also no retraction during layer change.

usually I print these in a pair. and I was just getting lots of spaghetti and failed prints every time. Guess as a pair once the layer slippage occured the tops of the models were uneven and the nozzle or fan caught and knocked the back model off kilter.

Totally bizarre.
used different filaments as well - just in case.

First time since I've had the printer that I've had any kind of persistent issue.