Colin i did not dismiss your idea, i was told from the horses mouth i did not need 2 inch hose so i had no reason to not accept his opinion as definitive.
Personally i will get 2 inch hose sooner rather than later as the cost is minimal, and your logic is sound the larger the diameter for the air to flow then this will minimse foaming, i suspect the cause though lays elsewhere, the lid or split in the tank or hose, i have not had this problem on every job though so its odd.
Regarding people helping i am always surprised and thankful that people give there time to help out, i just got a little irritated that people were asking questions that if they had read my post properly would not have asked questions i had already answered.
Had a bad day making icecreams with the airflex, indicators on my van packed up, went to look at fuse box, and it was different from the instruction manual so no way of knowing which fuse relates to which, bloody French.
Just after that stupid women who has re booked a big job twice :
cancelled