sliding canopy
Les. I know what you mean.. I have used the UP1 and UP2 valve with great success.. you restrict the air flow via the valve. I haven't used the Robart valves so I can't speak for them..?? I have used the restrictors... mine are so old tho I don't know where I got them?..
My advice would make it a "hand job".. manual operation...LOL.....Regards BobH.