Building a Workshop Gantry Crane

I need to be able to lift the engine into the chassis, but due to the lowered floor of the work area a standard engine lift won’t work. While I’m at it, it would be nice to be able to lift the entire assembled car off the build table, turn it ninety degrees, move it to the door, and roll it out of the shop. Below is the solution. Sorry there aren’t any plans. The build process was “go to your local metal recycling center, buy some scrap beams, clean them up, cut them as necessary, and weld them together”. I’m getting more comfortable with winging it in the machine shop.

Also shown below is a mount I built to mount an angle grinder on the lathe. Parting-off has always been a problem. I’m just about to make the engine mounts, requiring at least 36 cutoff operations, and I figured I’d better solve the problem. I have a cutoff tool but only purchased a small number of carbide inserts; the inserts wear out really fast and I either have to order more from the US or drive at least an hour to a store that MIGHT have them. This baby works great, giving a clean straight cut. Just have to be careful not to let the abrasive get into the lathe.

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Steering Column Supports

Next up: mount the steering column in the chassis. Nothing magical here, just lots of little steps. The steel bearing cup insert did work well at preventing distortion during welding. To get a proper press fit for the rear support bearing I decided to use my new internal bore gauge. At first it didn’t work at all (made in China, of course), so I had to disassemble it completely, figure out how it was supposed to work, unstick the rusted shaft, replace the dead battery, and reassemble it. All in a day’s work out here on the frontier. So now I can measure both holes and shafts to a few microns and press fits are much easier to make.

Fabricating the Steering Column

I originally sent all these parts out to the CNC shop, but they never got back to me with a quote so I ended up making everything myself. The spline onto the steering rack was a tight press fit, so for now the entire column including the rack is a single assembly. I don’t know it’s possible to remove the rack later, and I’m not going to try as it might destroy the rack. The U-joints are special units from Sweet Manufacturing in the US, but don’t seem to be anything special. In the future I might try to adapt standard Honda steering column U-joints and column splines. These use a perpendicular pinch bolt so the column can be disassembled at each joint.

Fabricating the Seat Bottom

Just a quick update here as the next one will be big and I want to keep it together as one post. I want to get all the tabs and brackets attached to the frame as soon as possible so I can paint it, so I started with an easy one: the seat bottom. I had the pieces laser cut, but the shop forgot that there are two identical side pieces and I had to cut that one by hand. I turned out to be easy after making a paper template. Each of the four pieces is a section of a cylinder and some of the edges intersect off-axis with frame tubes, so those lines that look straight really aren’t. The seat bottom is curved like this to get the driver as low as possible, mainly to keep the top of the main roll hoop as low as possible. The curvature was easy to make by just bending the steel by hand and fitting it by eye to the frame.

Attachment points are carefully spaced more than six inches from each other to comply with the F1000 rule outlawing stressed panels (with certain exceptions). It would have been much easier to just weld each piece to the frame tubes below it, but I don’t plan on this counting as the stressed belly pan. A stressed belly pan will be added to the planar bottom of the car. Making the seat bottom removable gives the advantage of easier access to the triangular compartment below it for mounting the fire extinguisher and whatever else will fit, and I can also replace the seat bottom later with a carbon fiber and kevlar version to save weight. At the moment I’m appreciating the fact that certain important body parts will be protected by two layers of steel in the event of a crash.

Fabricating the Lower A-arms

No, I haven’t just been sitting around the house eating chocolate, but a major malfunction in my main computer leaves me time to update the blog and get caught up on other things I should have done, like taxes. Unlike EVERY OTHER COUNTRY IN THE WORLD (except the Phillipines), even though I haven’t set foot in the USA in over four years, I still have to pay US taxes. The bright side is that California no longer considers me a resident so I don’t have to pay California taxes anymore, which is quite reasonable given that I moved out 11 years ago.

I made the mistake of turning the computer off overnight to help save the planet and all, and the next day it kept dying like someone pulled the plug. Computer shop says I need a new motherboard and graphics card, and oh, by the way, there are no new LGA 1366 motherboards for Intel i7 CPUs in Thailand and the old one will take about a month to fix under warranty. Which is understandable, given that Intel stopped making LGA 1366 i7 CPUs ages ago! Oh wait, they still make them? Or maybe not, from Intel’s website I can’t tell. At least Gigabyte’s warranty will cover their product, or maybe I just haven’t heard what their fine-print objection will be, yet. Azus, on the other hand, says my graphics card is corroded, and corrosion isn’t covered under warranty. Great plan! Make a product that corrodes, then say corrosion isn’t covered. It might be more honest to say “No Warranty”, though. The Azus graphics card was inside a warm computer (which was _almost_ never power-cycled) in an office environment for it’s entire life.  Azus is now on my Deferred Vendor List.

Anyway, on to fabricating the lower A-arms, or control arms:

Class Photo

Repeat everything four times. Final result: four lower A-arms

Building a Simple Hydraulic Press

I’ll be needing a press to insert the spherical bearings into the control arms and to insert the wheel bearings into the suspension uprights, so I took a couple of hours and built a simple hydraulic press. It’s just a strong steel frame that will give a small 5-ton hydraulic car jack something to push against. It’s taller than it is wide to be able to press items of different sizes by turning the frame on its’ side. Regarding painting, I’m finding that, with modern paints, I don’t need to use primer. I just clean the metal with a wire brush on a variable-speed angle grinder, clean it again with acetone and paper towels, then spray the topcoat on directly. This gives a thin, hard coat that sticks well.

Building the Frame: Roll Hoop to Tail