3D Printing

[Harry Babb]

Bob Lico.....this made me think of you! ! !

[Rawleigh]

Cool! I wonder how long before it becomes cost competitive?

[Harry Babb]

Rawleigh

In our industry the 3D printing is good for complex "One Off" parts or parts that are complex with tight deliveries.... where there is no time to make patterns and molds for the foundries. I'm pretty sure that the WAAM propeller was made just to show capability and then backup quality and performance by an actual real world application......its really cool! ! !

We do that sort of thing all the time reclaiming or refurbishing impellers as well as other damaged castings....on a much much smaller scale of course.

hb

[Stephan]

Very Cool-
I wonder what the differential in stability and performance is between the raw printed part and the finished one - it looked like a lot of grinding to get there!
I thought it was particularly interesting that the printing mas done on a rotating axis and not a horizontal slicer like the kiddie tools I've seen.
Harry-
Do your systems work around an axis like this?
Best,
Stephan

[Harry Babb]

Stephan
I am sure the performance would be very poor when the propeller is in the raw state. It would compare to having barnacles on the faces of a propeller blade and efficiency would suffer. Even when the propellers are "Cast" using sand molds (a very common practice) the props require a good bit of grinding to generate smooth blade surfaces. Grinding, whether automated or by hand, is a major operation in producing "Cast Products".

Our operation is NOT nearly that sophisticated....when we are required to "Build Up" surfaces its mostly by hand and sometimes aided by "Low Tech" welding positioners and manipulators. We are actually a machining/manufacturing facility....welding being a support operation to machining. I do know that when we repair impellers, we have to dedicate a lot of attention to the "Trailing Edge" of the blades and taper them like an airplane wing to minimize drag and increase pumping efficiency.....all by hand and eye! ! A lot of detail goes into creating geometry for good hydraulic flow.

hb

[bob lico]

i actually tried to come up with a mathematical proportion on using a common diameter (21") prop then change the pitch and the cup on a linear scale, however, the shape of the ear variable made that method difficult so i stayed with the rounded "mouse ear design" rather than the more pointed tip style which is better for an IO. with more beneficial shape for water turbulence around the prop . fortunately, i had the shop to play in and a whole bunch of other people props to play with. most abandoned by customers but a few---- well we won`t get into that. i would never have imagined lower the pitch and increase cruise speed results by redesigning the hub, cup. know i stay away from those machines i might forget where my hands are.