I came across this picture in a design guide brochure for a 3D printing service (Xometry). Immediately recognized the trochoid shape with cooling chambers. I was going to inquire about the cost of the part and whether dissimiliar metals can be combined in one cohesive part. Anyone in the rotary group recognize it as their own?
       Daniel Tyler
       Inline image 1



   Could they be making the part in wax or low temp plastic then casting the housing?  Wouldn't the housing be stronger if ot were cut from billet? (Using  a water jet cutter to avoid heating the metal ?


   Rob Miller

Paul, Rob,
I have done a lot of research on the DMLS process. This is not wax! This is directly FUSED metal. The resulting solid is generally as good as billet material. This additive process uses the laser to melt the layers together. many exotic materials are available. The earliest use I saw of this technology was it make new shape jet engine compressor blades. This is a very highly stressed part and the DMLS process was making a nearly finished shape. Very little post machining. The price varies based on how exact you want the part and the finish. If you want a very good surface the layers must be very thin and the laser time will be high. If you can deal with a fairly rough surface say +-.010-.015 it is considerably cheaper. That rotor housing would require inside finishing and coating, but the outside could be left as is. The water passages might even benefit by having more surface area.

Bill Jepson



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