Did you get the F85 plans?
I use plastic domestic irrigation hose and fittings. They are cheap as chips and work great. The hose slides over the bayonet fittings and seals.If ever in doubt I wrap a bit of tacky tape around the join.
I was surprised to find that even the taps are air tight and will hold a vacuum for many hours. I was just thinking that you could do it quick and dirty by putting in a "T" piece and a tap. Leave the piston pump running and regulate the vacuum with the amount you open the tap. I suppose it all depends on how much you are going to use it. The system Mark has put together works great for me as I'm doing quite a lot.