Bonneville Refresh

[Alyn]

For a rear axle, I started with some early Ford tubes. The chrome was stripped and a center section fabricated to match the flange diameter. Additonal bits were added to form the strengthening ribs of a typical quick-change casting. I used pictures of several styles of quick-change housings from the internet for reference.

I made another attempt at a chassis picture to show where the fuel tank nestles up against a roll cage X member. The top also has to slope down to clear the bodywork(trunk).

[Alyn]

Here's some more ...

The butterfly style wheel was drilled and filed out of a strip of brass sheet stock and then bent into shape. The upper shaft is also brass; sliding into a brass tube, but the lower shaft is styrene and the joints are aluminum. This joins with the scratch built steering box in the first pic. The dash panel is also brass sheet. the small stubs of white styrene are the start of a row of toggle switches. The larger ones are the back side of the gauges. I thought these were pretty cool until Scott Colmer put me to shame with the gauge set he scratched for is Bonneville Corvette.

[Alyn]

Here's an eagle eye view of the chassis layout. You can see how the fuel tank has to fit in a pretty small space. Everything you see in this picture except the seat with belt hardware and tires is scratch built.

[Raul_Perez]

AWESOME WORK!!

Everything looks well thought-out, considering the limited amount of space that you have to work with!!

Keep up the GREAT work!!

Later,

[Alyn]

Thanks alot for the great words of encouragement. The scratch building is where I get the most enjoyment out of model building; "mini engineering". Packaging is very important in a land speed type car. Anytime you have voids inside the body, you are potentially increasing frontal area, so all space should be used or eliminated. It all gets wrapped in a body and the body should be as small as possible.

Here's the finished product of my scratch built quick change. Brake lines are made from beaders wire. I think the flexible line is 26g or 24g insulated wire. The moon hubcaps are made from the bottom of Sprite cans. I thought they looked too flat, so I added some dish by shaping them with a round steel ball.

The track bar is based on some designs I've seen used on local circle track cars. In the real world, I'd use a longer bar to minimize side movement as the bar moves through it's arc. On a LSR car, suspension travel is minimal, so this style of shorter track bar is perfectly acceptable. It's actually solid rod, but I drilled out the end for the appearance of tubing. A bearing allows it to rotate at the carrier mount.

Edited August 12, 2009 by Alyn

[Fuel Coupe]

very impressive work here. I really like your work. How about a tech or tips on how you steering knuckles are built....

[Alyn]

In answer to your question Dave, I cut out the bottom of the can with anything I can get my hands on. This one was cut out with a cut-off disk on my Dremel. I've also used a "death saw" on the Dremel, but it made a cut that was a bit more jagged. It really doesn't matter since I cut a disc that is way bigger that the final size. While out walking with my wife, I look for aluminum cans. Most of dimples or numbers lightly stamped on the bottom, but these Sprite cans were pretty smooth.

The blue circle was drawn with a Sharpie around a dime. In my case, the dime was perfect. Your mileage may vary. I cut to the blue line with a small sharp pair of cuticle scissors. Then a a short section of 3/16" round styrene rod was epoxied to the back side of the disc so it can be chucked up in a drill. With the disk spinning in the drill, you can scribe or draw a more concentric line on the disc. Trim again to this line and then back in the drill to file and sand to a more precise round shape. Finally, with the disc still spinning in a drill, sand the face of the disc to give it the spun aluminum look. If I remember right, 400 grit worked well for this. I have been able to do part of the rotary work with the disc attached to a blob of modeling clay on a rod (in the drill), but you have to keep the RPM's down and expect the thing to go flying on occasion.

This is a fair amount of work for a puny little hub cap, but there's a lot of pride in being able to say you built them from scratch. At least that's my story.

Edited August 12, 2009 by Alyn

[Alyn]

Thanks for the compliments, Shane. Coming from a guy with your skills, they count double.

I personally don't think this is the optimum way to build knuckles. They end up a little bulky, so the next ones I build will probably be done in brass. Here's some basic info on how they were done.

I started by making some eccentric bushing to fit the ends of my axle tubes. The hole through these styrene rods are crooked on purpose. A straight pin is used for a king pin. It slides through the hole in these bushings and when they are rotated, I can adjust the castor and king pin inclination.

The knuckles begin with a short section of styrene channel that will fit over the axle. this is trimmed down and the tabs are drilled and rounded a bit. The inner edges of the channel are slightly slanted, so they and the tube ends have to be filed to produce a good fit. You can see the wedge of plastic added to the outer surface to provide a more vertical face for the wheel. This geometry is closer to a 1:1 design than is necessary. The end tubes on the axle could be soldered on vertically in which case the wedge would not be required.

Scrap styrene is glued to the knuckles to form the basis for the steering arms. These are also drilled for the pins, and then carved, filed and sanded to the desired shape. I tried to make the arms thin, but left a bit more meat around the end around the drilled holes for strength.

Here you see the knuckles roughed in. These are close to the final shape, but need to be smoothed out a bit more.

And, here's the final assembled parts. I probably could have done something to the pin heads rather than just leaving them as smooth, bright metal. The tie-rod is 3/64" brass tube with some railroad stanchions for rod ends. I like the ones you use better than these, but these are available locally. I had intended on adding a small piece of hex rod at the ends of the tie rods, but ran out of the necessary "round tuits". The spindles are just Revell stub axles, but could easily be made from brass or steel rod.

Edited August 12, 2009 by Alyn

[Bernard Kron]

At first I wondered why you said you were glad you were revisiting this build. But now I understand – compared to v.1 it has a totally different feel. I suppose v.3 will be when you take all the beautiful work from v.1 and v.2 and mount it to a frame made of smaller tubing like you wished you had done originally. But save that one for another time. You – and we – are having way too much fun with this one!

And thanx for sharing all the great scratch work from v.1…

B.

[Raul_Perez]

This one just keeps getting better with each new set of pictures that you post!!

Yeah...there's nothing like building small, detailed parts with brass, if you have the right equipment and skill to pull it off.

Keep up the GREAT work,

[Fuel Coupe]

good stuff Alyn. Very impressive...