Sunday, March 20, 2011

Part 8 - Regulator and CNC Switch Mount

The original plan was to mount the oil filter and regulator on a nicely chromed dual mount (see Parts blog). It didn't fit on this frame most likely due to the single down pipe.



The alternative was to fabricate a mounting bracket for the regulator and purchase a new oil filter mount that attaches to the EVO motor in traditional Harley fashion.

Alternator and voltage regulator


To create the mount, a heavy duty aluminum angle extrusion left over from a previous project was used. Cutting it to size was the usual death defying feat involving a chop saw and a huge amount of luck. Not recommended.


Regulator mounting bracket - front view

Regulator mounting bracket - rear view
The regulator is mounted to the bracket with 2x 1/4-20 SHCS. The bracket was tapped so eliminate nuts.  The other 2 holes are 3/8 clearance holes for the front motor mount bolts. The bracket is bolted to the underside of the frame and held in place by the the front motor mount bolts.

Regulator mounted

The ignition switch was next. There are a number of switch mounts available but decided to fabricate a custom part from 1/4" 6061-T6 aluminum plate. The switch mount also serves as a spacer for mounting the ignition coil to the top motor mount. Without the spacer, the ignition coil would be resting on the cooling fins of the cylinder.

The basic design was sketched on a piece of paper taking measurements directly from the top motor mount and the ignition switch. The paper sketch was then detailed using a CAD program - Alibre Design.



After messing around with a number of different designs, the basic design shown above was as far as my creativity would stretch. The vertical slots were added to create visual interest and serve no practical purpose whatsoever. After the CAD model was completed, a 2-D drawing was created and exported to a CAM (Computer Aided Manufacturing) program. 

Toolpaths for cutting the part
The toolpaths were created and downloaded to a CNC controller (Mach 3) which controls a homebuilt CNC machine that profile routes the part. The CNC machine was built from scratch a couple of years ago. 

Going from paper, to CAD to CAM to CNC Controller may seem like a lot of steps to get to the end product but the accuracy and finish of the part makes the process worth while. Cutting the part out by hand would take significantly longer and the slots would be a real challenge to keep straight using hand tools.
  
CNC Machined switch mount


Switch mounted
The switch mount still needs to be polished to match the shine of the primary.