28 Feb 2010

Turns out I had it easy with Kimini, as do Locost builders with their cars: being handed the basic shape, be it plans in their case, or a carbon shell in mine. With Kimini, I had the luxury of building a car to a shape conveniently defined by someone else. With Midlana, however, I get to deal with something new, something I’m unfamiliar with – styling.

I almost got away with it, too, more or less copying the Lotus Seven shape, but am changing things as I see fit (be careful what you ask for…), like the area immediately ahead of the rear fenders. I’ve seen how beat-up Lotus/Locost rear fenders get, pelted by sand and pebbles. The usual tactic is to either ignore the issue, or add stainless shield rock-deflectors. Of course, then the stainless shields get’s beat-up, being – like the fender – directly facing the onslaught, sometimes bouncing stones into the car. Then there’s the case of autocrossing the car, cutting close to cones with the front tires, only to have them smack the rear fender and possibly cracking it. (And yes, I know, “don’t hit cones.”)

Finally, because Midlana is mid-engine, cooling air is needed for the engine, oil-cooler, intercooler, and maybe brakes. Which brings me to now: how to integrate stone deflection, cone “nerf bars” and air-inlet vents into an aesthetically-acceptable shape. Of course, I knew going into this that side-vents are such a subjective issue that no two people agree on what looks best. For that reason, every builder’s free to do what they want, and in fact there’s a thread in the forum with potential builders voicing opinions on what looks good.

Shown here is half a day’s effort of messing about with cardboard, scissors, and tape. There’s several different attempts: different sizes, lengths, and shapes. I’m undecided for now; maybe by next weekend I’ll either give it another go or just call one of these good enough and get on with things.

21 Feb 2010

It finally hit me, standing back and looking at the rear fender – it’s starting to look like a car, and a small car at that, even sitting half an inch higher than final ride-height.

Back to work tomorrow; everything on the floor was cleaned up to make room for my dear wife’s car once again. It’s just as well; it’ll take some time to think about how to do the vents.

20 Feb 2010

Drilled lots of holes, switching back-and-forth between the air/battery-powered drills when the compressor/battery needed a break. Added a couple diagonals across the forward floor. The thinking is that people will step into the seat first, then slide down into it. Getting out however, they’ll likely put most or all of their weight on the floor. Since it’s only 0.050″ aluminum, additional support is needed; I hope the 0.75″ stiffeners are enough… maybe should have gone with 1″.

At the end of the day, the next panel to do was the one below the fuel tank, but to make sure it fits perfectly, the panel under the engine may as well be installed first. That means it’s finally time to deal with the last undefined area of the design: the side air-inlets ahead of the rear wheels. The car will be sat back down, spaced off the table at its designed-to ground clearance. One rear suspension will be bolted on, one wheel, a fender (and maybe a panel riveted-on behind it.) Then, various paper patterns will be tested out to see if there’s a mix of functionality and aesthetics that’s acceptable. The trick’s going to be to come up with a shape that’s single-plane bends yet decent-looking. Good stuff!

19 Feb 2010

I thought I had pretty much experienced everything that can happen when TIG-welding. I was welding some 1/8″ material, which requires decent current. I was feeding the rod into the puddle and it stuck briefly, then sprang free, welding itself onto the tungsten. Thing is, I was leaning into the chassis at an awkward angle, so the other end of the rod was against a grounded chassis tube. So until I was able to get my foot off the pedal, there was about 100 amps flowing through the rod… that was in my gloved hand… boy did that get hot in a hurry! The thumb of the glove has a nice burned line across it – could have been my fingers.

Finished the welding, at least all the missed spots I could find – some of them are hard to spot. Anyhow, today marks the transition into the next phase, paneling the floor. For some reason, the local aluminum supplier doesn’t stock 2024, which is what I really wanted, but since it isn’t structural, I just went with what they had, 5052.

This place has the strangest pricing structure. If you want a 4 x 4 ft sheet of the stuff, no problem, they keep that size in-stock, cut down from 4 x 8 ft sheet. So I asked for an uncut sheet, figuring it would be slightly cheaper since they don’t have to cut it. The surprise was that it’s  nearly twice as expensive per pound. I asked the counter guys about half a dozen different ways to make sure I wasn’t misunderstanding what they were saying, and that they weren’t misunderstanding me. Nope… sigh.

Fine, so instead of the floor using a 4 x 8 ft sheet, it’s two 4 x 4 sheets. I’ll have to figure out something for the side panels – those will need to be 8-ft. Sooo, anyhow, the first sheet’s been cut and the first row of Clecos installed. I actually enjoy this part of construction, probably because the parts involved are once again larger in size 🙂

Also picked up a small sheet for the dash. Between wiring the dash, making the fuel tank tray, and drilling lots of rivet holes, I’m set for now.

18 Feb 2010

More finish-welding. Normally, I pick up metal stock at lunch during workdays, since the metal supplier’s closer to work than home, and more importantly, isn’t consuming valuable work time. However, finish-welding will probably be done tomorrow or Saturday for sure, and I need material on-hand so there’s no lull in progress. So, took some time off from the garage (have the week off) and picked up enough aluminum sheet to do the entire floor, plus steel for the fuel tank cradle – that’s definitely enough to keep busy for a while.

17 Feb 2010

Added a few more gussets and floor diagonals under the engine. Removed everything from the chassis so it can be rolled on its side or back. The chassis isn’t complete; the idea is to finish everything near the floor that’s been tacked-welded. The idea is to fully-weld everything so panels can be attached without concern about heat-distortion shifting the rivet holes.

There’s still lots of tabs and brackets to weld on for the seats, fuel tank, coolant tanks, seat belts, etc. However, they don’t require pumping a lot of heat into major tubes and can be done later if desired.

15 Feb 2010

Odds and ends. Went ahead and – after placing the seat just right – welded on the quick release fitting. The steering is now complete; it feels good turning the wheel and watching the hubs turn. By eye there’s some bumpsteer, though that’s expected since the rack doesn’t have its spacers yet and is missing mounting bolts. Speaking of lack of hardware, with no nuts or spacers on the suspension bolts, everything is real sloppy, so for a change of pace, cutting, drilling, and welded stopped while all the needed bolts, washers and stop-nuts were totaled up and ordered. Getting AN hardware in there will go a long way toward a rattle-free suspension.

Welded in the last bearing cup, finishing all the A-arms, though they need a few more gussets. Right now I’m “suspensioned out” and ready for a change. That’s the thing about building a car; it’s like moving an enormous pile of boulders, rocks, pebbles, and sand. There’s no point worrying over what exactly should be moved next because it all has to get done eventually.

Made a list for all the needed aluminum paneling. Kimini had a stainless floor, but because the stuff’s not much fun to work with, I’m going with aluminum this time around. The main floor panel is 4′ x 8′, which will be interesting to get home since I have a small truck. Not sure I want to roll it up, but something will have to be done. Maybe curve it just enough to fit in, then tie it down; the concern is it’s a big surface area and the wind might try ripping it out the bed…

Starting to think about tires. I did learn something from Kimini, where tires were the first thing purchased, and they sat in the garage for 10 years… not this time. Technically the car could be set down on its suspension right now, but there’s not much point. The floor panel needs drilling, which means rolling the chassis over. In fact, before paneling, the chassis should be finish-welded so heat-distortion doesn’t shift the rivet holes after they’re drilled. And even after that, I don’t really want the car sitting on the ground – it’s too low to work on – so it’ll be on jack stands for a while, but we’re getting there.

I guess the thing to do next is add what few chassis tubes are needed, then completely weld the chassis. Better fill the argon tanks…

If anyone knows of a shop that can punch large louvers, let me know. I don’t mean little weenie ones like on air-conditioning vents, I mean ones like 6″ long, raised at least 1/2″… 3/4″ would be even better.

14 Feb 2010

Yesterday the right-side rocker arm was cut off and moved… grrr. Today, the steering rack arms were modified, extended to reach the outboard steering tie-rods. Pretty cool watching the suspension finally steer, and the steering’s done except for pinning or welding the quick-disconnect steering hub. That may wait until the seat mounts are in.

7 Feb 2010

After a very long push, the suspension’s done – almost. After the second rocker, push-rod, and A-arm were installed, turns out that the right rocker-arm pivot was welded in a bit too far inboard where so at full-droop the push-rod contacts the chassis – not acceptable. So next week it get’s cut off and repositioned. Not a big deal in the overall scope of life, but another lesson in what happens when things are rushed. Or maybe it is that there’s no one to blame…

The suspension has taken so long that not much thought’s been given to what’s next. The immediate list is: fix the mount, fully weld the chassis, and add a few gussets on various things (which ensures the drawings are – once again – out of date…)

I always make things out to be worse than they are, kind of like shaking my head at myself and wondering “what takes him so long?” Anyhow, things are moving along, because after the chassis if finish welded, it’s time to start adding panels – or do the electrical. Probably makes more sense to do panels first so it’s more obvious where tubes, cables, and hoses pass through, ensuring things don’t get missed. Paneling will be a welcome change.