Another hand-crank bellows design...

[nashdude]

I'm still researching the whole centrifugal bellows idea, and I ran across this little gem. It needs tweaking for max performance, but it gives the same general idea of what I was talking about in my "busted leaf blower bellows" discertation

Blower Plans

[nashdude]

WOOOHOOOO!!! Jackpot!

http://www.vintageprojects.com/home-garden/LeafBlower.pdf

[BeaverDamForge]

I'm still researching the whole centrifugal bellows idea, and I ran across this little gem. It needs tweaking for max performance, but it gives the same general idea of what I was talking about in my "busted leaf blower bellows" discertation

Blower Plans

That's close to what I was thinking of. I'd use an impeller with sides, or at least one side (leaving one side off would prevent backflow on the outside of the impeller but makes supporting the vanes harder); it looks like the hub is blocking most of the intake. They mention leaving the sides square which would be easier, but they shouldn't be circular with little clearance as shown. I was thinking of blocking three corners to make a semi-octagon, and putting the outlet in the other corner. Leave some room for air flow around the outside of the impeller. The outlet should be close to the size of the piping, no point in leaving it large then reducing it. Of course if you leave the housing square and just drill a hole for the pipe it would work.

No dimensions are given, but the diameter of the impeller will relate to the speed it needs to turn. That's why I was figuring 21-22", the housing sides could be 24 x 24" which fits conveniently on a sheet of plywood. The width of the impeller doesn't have to be much, if any, wider than the piping. Wider would flow more air but it has no place to go so it would just make cranking harder.

1/4" ply with some framework may be cheaper and work as well.

I don't see where the gas powered leaf blower PDF is relevant. It's designed (the impeller in particular) for lots of RPM and way more flow than a fire needs.

My $ 0.02

Good Luck! Edited December 30, 2008 by BeaverDamForge

[nashdude]

I don't see where the gas powered leaf blower PDF is relevant. It's designed (the impeller in particular) for lots of RPM and way more flow than a fire needs.

Yeah, I didn't look at it real good before I posted. I just saw "plans" and saw the diagram and assumed that there was something included that obviously was not.

Good comments, bro. Thanks!