I myself left the Pipe and valve on the compressor and a had a special pneumatic push fit on the end and used the lever from the valve as my Dump valve. This worked extremely well and I never once had a problem in Turbine 3.

An alternative method would be to get some 6mm id nylon tube and get it crimped onto the output of the compressor; this is what Tkm2 do with success; however the tool to do the job is rather pricey just for doing a one off job.

Ill bring some of the brass push fits along to FWS if you are going ask me and ill give you 1. Also I would recommend you get a pressure switch from technobots so when your compressor reaches the maximum pressure of 10bar it will fire a relay to switch of the compressor. Best of luck.

Regards
Dave moulds
Team Turbine/PLF