Thank you guys for the suggestions. At the end I got a recommendation from my friend for a local store: https://cryptomining.sk/en/product/hlinikovy-rig-na-7-vga/
For start I bought one and built it during the weekend. It looks pretty nice and robust construction. Here is how it looks

Hello there, I am looking for some proven rig frames. I use now a home made ones from a plastic containers and they are terrible for component maintenance and just a simple movement with it is a pain. Looking for something durable, easy to build, for 6 graphic cards, for less than 100 €. Any suggestions?

Hello there, I am looking for some proven rig frames. I use now a home made ones from a plastic containers and they are terrible for component maintenance and just a simple movement with it is a pain. Looking for something durable, easy to build, for 6 graphic cards, for less than 100 €. Any suggestions?