LP air key

[Shrub]

Ok fair enough LP in this instance is used for the term of Low Pressure,

I love your idea of a key blank, drill down the length of the blade then drill down perpendicular to that in each of the cut places 5,6 etc then blank the end hole off, i like it and fancy actually having an experiment myself now,

Spool pins may be an issue if the air travels around them and goes in to the void in between then the pin may be sucked down instead of blown up but only tests will tell.

[helix]

Couldn't you just use a footy pump needle with the
end squeezed shut, and a heap of little holes
drilled in the top?

[vector40]

I can't imagine that would provide enough pressure.

[Shrub]

Vec, he was meaning to use the needle for blowing up a footbal not the actual pump (i think )

Helix, yes it probably would but you may find it a pain to get accurate holes in it, i think a key balnk would be the best as all you have to do is to put the blank in a plug, spot through the chamber holes on to the blank with a 3.2mm drill bit, take the blank out and you already have all 5/6 holes centre drilled redy to just drill out at a guess somthing like a 1mm hole,
A 4 jaw chuck in a lathe or careful lining up with a drill press will get you the hole through the bow and along the blade (you may have to cut the bow off to get the drill to go deep enough to hit the 5/6th hole),

Good idea though but im sure the needle is dearer than the blank.