Just finished my replumb of the airlines on my Hawk with I am pleased to saysuccess.

I have one very large Robart air tank over the fuel tank plumbed into the gear circuit only,and one large BVM air tank each for door and brake circuits,all independent of each other.

I have used 3mm Festo tubing from the gear cylinders and the festo tubing goes on to the large nipples (Ijust love large nipples)as DW has said without any problem as festo 3mm tubing has a larger ID to BVM tubing.

While my retracts were out of the model i filled a small amount of 100wt silicone model car shock oil into the cylindersto lube the O rings.The silicone shock oil softends the O rings and makes them swell a little to give a good seal.

Left all the JDvalves as before and now I can hold 120psi for half an hour with the radio on.

Phil.