Big makers pre-production automobiles

Factual Questions
1

With regards to the “big” automakers that don’t typically do a lot of “hand making” of their autos but instead rely almost completely on the assembly lines turning out 100s a day.

When there is a big change in store for a model, how are the first (relatively few) “pre-production” but feature complete vehicles made? Are they hand made?

The reason I ask this is that Ford is reportedly changing over their F-series production lines in June to the newly remodeled truck, which will take (according to Ford) about a month to retool the lines with a ton of production time lost and a whole lot of $$$. However, there are already some of the trucks running around doing tests, photo ops, first impressions, yadda yadda. This seems to happen quite often with other models as well, with “previews” and the odd test drive of a model months before they even hit the showroom floor.

2

The parts are not made at the assembly line. All the parts are tooled up well in advance of production models coming off the line. The pre-production models are more hand assembled than hand built as a true prototype would be.

FWIW there are often disguised test prototype and preproduction vehicles on the streets of Phoenix. I’ve seen a few big GMish looking vehicles clad in what looks like an extended car bra. Every square inch save the glass and wheels is covered in zippered black naugahyde making them look like an SUV version of the Gimp in Pulp Fiction.

3

I worked for Ford around 1980 supporting analysis of barrier tests (i.e., safety tests crashing the car into a concrete barrier). These were pre-production cars and cost hundreds of thousands of dollars each because they were each built by hand. Part of my job was to increase the efficiency of test analysis so as to maximize the numbers of tests that could be done in a single crash. Also, these were not “feature complete” since they did not have to be.

When the Escort was being design, I believe the early test track runs involved a Pinto chassis and drive train with a hand made body.

This was 20 years ago so what they do today may vary.

4

Hand assembled, all the way.

The are varying degrees of what needs to be built in order to assembly a prototype vehicle, depending on the degree of change from existing models. For example, a new vehicle may use an already existing engine, or a modifed version thereof. Therefore an engine (or other already-good-enough subassembly) can be ordered directly from the plant that makes it, making many parts really quite cost-effective to procure.

In other cases, mass-produced parts that are “close to” the part the engineering team really wants are bought off the line and modified so that they work.

Additionally there are a large number of job/fabrication shops (some belonging to the manufacture, many outside the company) that do small batch runs. Say you need a few deck lids – company will design some dies, some sheet metal will be stamped, and you have some very expensive doors, deck lids, fuels tanks, whatever. Eventually these dies or others will end up in a “real” stamping plant for mass production.

Even cars touted as “as all new” typically are evolutionary rather than revolutionary, so a lot of the super-expensive, high-precision stuff doesn’t have to necessarily go through the same, small job shop runs.

Sometimes plants are all new. Sometimes plants are retooled, which means add kits to what’s already there, or rip out everything and start from scratch. Starting from scratch takes longer, and you lose the ability to build what you’re already building. Kitting can often be done on an off shift, or during a scheduled plant shutdown in a lot quicker time. So the first true production vehicles can roll off the line with very little loss. These pilot vehicles typically will not be sold to the public but use for all kinds of internal purposes.

The increasing use of flexible automation will soon make it possible to do much of the model change changes in software. Dump the new program into the PLC and robot, put the parts on the line, and (theoretically) start building the new model right away.

Oh, FWIW: low production vehicles are sometimes hand assembled. The EV1 was completely hand assembled in the Craft Shop in Lansing, MI.