Philo, for what it is worth, the beginnings of the turbine community were all built around homemade stuff.

I have seen a turbine with a wooden compressor run on propane with a coffee can as the can. It put out 7 lbs of thrust and cost about $200.00 US in parts.

It had an on board oil pump to put oil to the bearings.

There are many ways of making your own stuff to keep costs down, and tinker with other building aspects of the hobby while you do.

Whether it is safe or not, is outlined by the builder, and not governed by RCU or its participants (thankfully)