Photo 36 — This picture illustrates the need to adjust the milling bit down a few more thousands of an inch before proceeding with milling the rest of the block.
Photo 37 — The turn signal indicator aluminum block is completed in milling one side using the 3/8 milling bit. Note that tool marks left on the surface are normal when milling surfaces. Depending on your project, they maybe removed via filing or sanding.
Photo 38 — The alum block is held in a vise on the cross feed table and the block is positioned under the milling bit. The bit will be lowered into the block and light passes are made by moving the cross feed table under it back and forth. This is also referred to in the industry as hogging out a part. Shown is the 0.125 inch depth pass.
Photo 39 — The completed turn signal indicator. The two LEDs are held into the block with small locking nuts and the wires are encapsulated in hollow parachute cord. Strong magnets hold the indicator onto the dash while driving and permits removal at a show if the owner desires.
Our final project is a running board spot light (Photo 40) which is a work in progress. The light was purchased at a flea market because the drum shape of the lamp closely matches the shape of the headlights on our project car. The modifications required are a new base pole mount, created using the lathe, and cutting a straight tooth gear (Photo 41) which uses the milling head and an accessory called a dividing head. The dividing head permits a part to be rotated an exact number of equal parts, sixteen in the case of this gear. A dividing head is the type of accessory which you may only need occasionally, so it may be hard to justify the investment. In this case, we borrowed one from a fellow collector.
Photo 40 — Two tasks have been performed so far 1) sizing and turning the brass pole adapter into the light's yoke, and 2) making a straight cut gear.
Photo 41 — Close up view of the straight cut gear. This brass gear was machined on the 1220 XL using the milling head and an accessory called a dividing head (not shown) which rotated the gear at precise intervals.
Drilling: Drilling on our combo machine provides precision when drilling holes in an exact location and to a precise depth. This precision makes it possible to change drill sizes while maintaining the same exact center. This is necessary when it is necessary to progressively increase a hole size). Further, if a hole needs to be shifted (redefined) or placed accordingly, precision drilling provides for this function. Good examples are removing a broken stud where absolute center is required or locating a threaded hole in a new casting. As a drill, combo units often include a drill chuck with adapter to a milling interface (Morse taper #3 in the case of the Smithy 1220 XL). Positioning the table under the drill permits precision drilling of the work piece for both X and Y directions and drill depth. Examples of precision drilling are drilling the holes in the above casting where the hole position would dictate the brackets position onto the chassis (see Photo 32).