I would like to build this and already bought the DIY tutorial.

http://www.rogerdodger.net/diyflightsims/ez_helicopter.html

Now what I did not thought about before if in Germany I can get 25mm PVC tubes that have at least a 2.5mm wall thickness. After some google hours I found one with 2.8mm walls but its so amazingly expensive that the parts together would cost 300 Euro. That’s quite insane.

Does anyone know a cheap Schedule 40 PVC pipe equivalent that also has 90°,45° and T- couplings?

sched 40 is just standard wall thickness for DWV (Drain, Waste, Vent) pipe. If you look under the sink in your kitchen or bathroom you'll see what you need, and what is common is Germany. PVC is a common material. You may have been looking at electrical conduit. It is more expensive.

The easiest way to find what you need is to walk into any large, suburban hardware store (home depot equivalent) and ask for plumbing drain pipe. They'll show you a bunch of options. A 10' length of 1" (25mm) PVC should be around 12 Euros. Each fitting should be < 1 euro.

Also, you could try asking a local plumber for some pipe. They would have access to everything.

The problem seems for me that for a 25mm 1 inch tube everything over 1.9mm is a waste of material as it can already sustain more than 10 bar pressure. I just googled over two hours and nothing. Its simply not a standard in Europe I guess. In USA google finds it in every other shop.
Would be crazy if i have to import this from USA.

Found 1.9mm thickness for a reasonable price, still connectors over 2 Euro. The US Schedule 40 is 3.5mm thick. I am afraid 1.9 will wobble badly. I also need a glue that is like the liqquid nails and available in Europe.
Anyone built this outside the US?

Alright found a shop where 1.9mm PVC is really cheap the Heli cage material costs 70 Euro. I really hope 1.9mm is strong enough. I will build it and report back.

http://www.pvc-profi.de/

If someone could help me with the glue that would be awesome.

Hi roads,

the glue you need is PVC cement. It bonds the pipe in seconds and it should be readily available in Europe I would think. Its not expensive at all. Comes in different styles (pink, red, blue gel type liquid)and you apply with the brush that's in the lid of the bottle.

You need to make sure you have your joints marked before assembly (dry run first and mark the pipe and joint with a pen for alignment) because once you apply the glue and insert the pipe it goes off in about 5 seconds.

Ok, you actually need 2 bottles of solvent for PVC. One is primer and it's usually purple, and the second is the solvent cement. In order to guarantee a good bond, don't skip the primer.

Thanks guys but the problem is the bonding time. Normally someone working with PVC tubes needs to glue it fast so most of them are quick bonding. In the sim pit case they are needed to bond very slowly so you can readjust the cage after gluing.
I mailed to the Rodger doger DIY cockpit guys and they told me to use screws. I will do that as I dont want to try out different glues. Reusability of the pipes is also an argument.

Found another shop in the UK

http://www.plasticpipeshop.co.uk/

prices are double of US prices but they are the original Schedule 40 pipes. Dunno is they even send to EU mainland.

I will use the 25x1.9mm and reinforce if necessary.