Posted by Clint Dixon [172.71.254.77] on Wednesday, November 05, 2025 at 08:22:39 :
I in no way have a connection to, or investment in, the reproduction of headlight bases. But as the Director of Quality Control at a production machine shop, I may be able to shed some light on what it takes to reproduce them. They may actually be one of the hardest parts to reproduce for a Power-Wagon.
The Power-Wagon headlight bucket starts out as a large diameter at the front and tapers off to a much smaller diameter at the rear. This is not a straight-line taper, but rather a taper on a curve. The diameter continually changes along the length of the bucket and at an increasing rate throughout. In effect, it is a three-dimensional continuing shape change. Although the headlight bases touch only a small area of the bucket surface, their mating surfaces need to match this continuing change in order to provide a perfect fit.
Where the bases touch the fender is not quite as complicated of a shape as it is basically a simple radius � a one-dimensional shape. However, this simple radius must be oriented in perfectly correct relationship to the three-dimensional shape above with no straight or flat planes or axis as reference.
If the reproduction parts are sand cast, they may be cast one at a time using an original to create the mold. If actual die casting molds were made to produce these parts, a massive investment was made to reverse engineer an original headlight base replicating the fender and headlight bucket shapes and contours. One has to consider just how perfectly shaped the original was and what kinds of software were used to do the reverse engineering.
Then, there is the problem of shrinkage of the part during the casting process. Each material shrinks to a unique percentage based upon that material�s composition and it is imperative that this is accounted for in the design of the die casting molds.
After this comes the problem of machining the raw casting. At a minimum are the holes and threads that need to be machined. There exists no flat surfaces or straight axis on the new parts to establish datums or even to clamp the parts down for drilling and tapping. Was specific tooling created to locate the raw castings in place for repeatability of machining and to allow strict tolerances to be held?
I am about 100% convinced that one could not machine these parts complete from dimensional stock. There would be no place to clamp the parts down to a work surface for milling without custom tooling above and beyond what would be required for finishing sand cast or die cast parts.
Anything other than simple sand casting one or two parts at a time before creating another new mold would require an investment far beyond what one could ever expect to recover, let alone make a profit on, something that in reality is in very low demand.
Unfortunately these parts may require some "field fixes' in order to get them to fit properly. Doing so only allows the owner to become more intimate with the restoration or repair of the truck. And, one may find that once they have been fit to one truck that they may not fit the next truck quite as nice.
I have found that swapping parts (original parts) between trucks can get quite interesting as the results are not always what one would expect.
Junior
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