Motor Mount 2.0

An alternate design being considered would incorporate "BMW style" motor mounts that would be bolted directly to the sides of a "clam shell" that encircles the body of the Warp 11.  This design would use the same foundry casting for the left and right side motor mounts.  The top and bottom castings of the "clam shell" , also identical, would provide an 11.45 inch opening when bolted together.  A differently sized  "clam shell" casting with a 9.25 inch nominal opening would allow for the substitution of a Warp 9 onto the same motor mounts. 

Mounting flanges at the equator of the Warp 11 "clam shell" would mate to integral flanges on the face of each "BMW style" mounting bracket.  To demonstrate the design, the previously sectioned BMW left side mounts were further sectioned (picture DSC05438) to allow room for the two mounting plates.  The sectioned BMW mounts are neither symmetrical or in good alignment when mounted, but they allow for a good visualization of a possible design. 

Picture DSC05438:  View of the final BMW left side motor mount (top casting in picture) after the final sectioning with a hand held band saw.  The additional removal of metal provides space for a flange to be welded to the side of the "clam shell" as well as a second flange to be welded to the mounting bracket.

Picture DSC05452:  Top view of the prototype installed on the top surface of the Warp 11.  Note the asymmetry at the mounting brackets.  The angle of the picture does not demonstrate the fact that both pairs of flanges are parallel to each other and equidistant to sides of the Warp 11 motor.

 

Picture DSC05451:  Anterior view of the top half of the four piece design.  Wood wedges were inserted to correct for a slight misalignment.  The wedges will be glued in place, and new dimensions confirmed on the workbench after the assembled framework is removed from the car.

Picture DSC05454:  Close up view of the left side mounting flanges.  The top and bottom halves of the "clam shell" will be joined together with a pair of vertical threaded rods or bolts (not shown).  A rubber trim element will be glued to the inner contact surfaces of the "clam shell" to provide for a snug fit and to reduce any vibration noise.  

Fabrication:

The design was initially drawn on 3/16 inch plywood and cut out with a table top band saw.  The outline of the design was then traced onto prototyping foam (McMaster Carr, part 3152T41).  The foam pattern was cut out and the two plywood pieces then glued to opposite sides of the foam spacer.  Two sets of temporary nuts and bolts were added to provide strength while the glue was setting and the sides sanded.  Four 4" by 4" plywood "flanges" were cut out with two of them being hot glued to the sectioned BMW mounting brackets.  During the trial fitting it was found that the alignment of the flanges on the "clam shell" was not correct, and wooden shims were required to correct the alignment.  The wooden flange on the "clam shell"(including the shims) were then glued in place so that upon removal from the car, the final dimensions would be maintained and measured on the workbench.

In the final design, both pairs of flanges would be parallel to each other and perpendicular to the horizontal plane of the car.  The foam core adjacent to the motor body was recessed to allow for clearance of the red painted bolt heads (two of which are visible in picture DSC05454).  These bolt heads are part of the Warp 11 motor.  The top surface of the "clam shell" is flat, parallel to the floor, and wide enough to assist in the mounting of a controller.  The merit of this design is that only two different castings are required for the project.  The top and bottom of the clam shell are the same casting, and both the left side and the right side mounting supports are the same casting.  A differently sized "clam shell" casting would allow for the use of other Warp style motors without changing the mounting brackets.

Motor Mount 1.2

The initial design, based upon the measurements described in the previous blog entry (dated 2/14/2013, Part 1), was constructed using 3/16 inch plywood, 1" thick wood blocks, and nuts, washers, and bolts.  The final finished product would be fabricated using plate steel and a good welder. 

The concept is to have a metal arch that rests directly on both BMW motor mounts.  By using three nuts, four washers, and a fully threaded bolt, it was possible to rigidly hold the two wooden arches parallel to each other during trial assembly and fitting.  The final design would include a metal band bent with a radius of about 5.725 inches (11.45 inches is the outer diameter of the Warp 11).  The base of each arch would be welded to the curved band.   Strategically drilled bolt holes in the curved base band would allow for the insertion of bolts directly into the motor housing.  These bolts would help prevent torque induced rotation within the motor mount while under full load.

Picture DSC05424:  View of the assembled wooden model of a mounting harness for the Warp 11.   The blocks of wood at 3:00 and 9:00 have not yet been trimmed to match the contour of the lower arch.

Picture DSC05423:   Anterior view showing the top half of the wooden prototype positioned for a trial fitting.

Picture DSC05420:  Top view of the top half of the wooden prototype.

This design requires that the arches be cut from steel plate, a curved base plate formed, and final welding all three pieces together.  The final height required to provide adequate strength of the arch (and the depth of the arch below the motor) has not yet been determined.  If the top of the arch were made flat, then the surface could be used as a mounting point for other components.  This design is simpler, but less universal, when compared to attempting to incorporate a modified BMW style left side motor mount as was previously described.