BostonWill wrote:
This is one of the cleaner cars I have seen built here! Says not only something about your skills but the approach of using laser cut materials and CAD.
BTW- did you use ant type of finishing on the outer skins? They look really nice!
Thom, This project was an experiment for me in several ways, but the big one was the use of manufacturing technology, as I mentioned in my first post. The idea was never intended to be "Low Cost" it was intended to be from a perspective of "can I play General Contractor and mostly be an assembler and substantially reduce labor?" Is it possible, as an amateur, to model a car and build it *to the model* and it all come together in the end? Would all of the effort/expense be wasted the moment the frame was welded? And many other questions. It was an itch that I wanted to scratch, whether it was the 'best' way or not.
Obviously it did add significant cost, but it also saved a great deal of labor. I've had zero regrets taking this approach and zero meaningful surprises or problems. In fact, it has been quite a pleasure building a car this way.
Would I do it this way again? As long as I could justify the funding, the answer is unequivocally yes… mostly. In my perspective there are three parts:
1) The CAD design of the frame including laser scanned drivetrain. This was the single most influential factor in the way the car turned out in terms of overall packaging. I was able to keep the hood low, the overhangs short, the frame tight around the drivetrain maximizing passenger space (especially the pedal box, 15" wide and tunnel, only 5" wide) necessarily because I'm a pretty large guy, and I didn't want to make the car any larger than it needed to be. It also allowed me to verify that I could install and remove the larger components into the frame before committing to steel. I would invest the upfront time again without question, even if I intended to cut everything traditionally.
2) CNC cutting the frame. This saved time but at a significant overall cost, percentage-wise. If I were to build another car I think that I would cut/miter all the square tubing myself and have all the round tubing CNC cut and bent. I estimate this would have cut the cost in half and all the time intensive stuff would be done leaving all the quick/easy cuts to be done manually. That would probably strike a better balance between cost and time.
3) The sheet metal. This includes the floor, firewall, rear bulkhead, firewall, tunnel, and all of the bodywork. Laser cutting these were probably the biggest overall time saver in terms of cost per hour saved. It increased efficiency in many ways, one of them was rivet holes. All except maybe 10 rivet holes were laser cut to a pilot-sized .100". Every hole hit a tube and they are all evenly spaced. This alone saved a notable amount of time and made for LEGO like assembly. It would be difficult for me to not want to do that again.
Obviously it's an individual choice, juggling your time vs. money and everyone has different priorities, especially in what they take pride in doing. My bent was a bit more toward the challenge of design and 'manufacturing'.
As far as the finish work, for now it's just bare aluminum that's been white Scotch-brite'd with WD-40 and wiped down with a micro-fiber cloth and isopropanol (don't leave WD-40, it's a dust magnet). I still have more of that process to do to get all the panels to the same finish. I haven't settled on whether to leave it bare aluminum, clear coat, paint, or vinyl. Not in a big hurry on that decision.
And thank you again for the kind words!