Scratch build hot rod engine

[Andy Oldenburg]

I had no kits on the shelf (imagine that!) and my order hadn´t arrived yet. But my fingers were getting itchy so I though of spending my time with a project, that I could use later. I dug into my spare parts box and found enough to build an engine. I will be building a hot rod in the near future so I decided to build a supercharged. Since I was getting some praise for my detailing (a big THANKS to everybody!) I would like to go through my steps. First, here is the finished project:

The parts come from at least 4 kits, so I had to do some adapting.  This is what I had to start with.

To get ahead fast I like to use a solvent that I buy from an artist and craft store in my town. The shop also sells items for architecture modeling like styrene rods, sheet and other materials. And "Dichlormethan". Only takes about 30 seconds to stick and then I can move on, but it dosn´t work good for the fine stuff. The engine block is quite simple and in no time I had the major parts attached. The holes for the exhaust had to be filled and puttied. After sanding a coat of filler primer.

The major holes for the sparkplug boots and the cooling hoses I drill before painting. The block is airbrush sprayed with Schmincke Aero Color acrylic artist paint and sealed with a semi matt coat.

The transmission and the pan were sprayed next after masking the block.

The charger parts I had to sand a bit to fit between the cylinder heads. The carbs were a triple that I reduced to double. The scoop didn´t match to the carbs so it had to get it made to fit and I added a metal grid to the front.

Like many supercharged engines this one gets a secondary cooling system, which I had to prepare before I start building the pulley system.

For the pulleys and belt I go the hard way and build it all new. Usually I deconstruct that part in the kit to save the wheels, some times I have to build the pulley wheels out of sheet styrene or short pieces of tube. Here´s what I started out with and the steps to the finished wheels:

About now it´s time to build the ignition distributor. You guess it, I build it myself. I was tired of trying to connect the wires to that tiny bud. My distributor is made of 2mm brass rod, 4mm aluminum tube, a tiny piece of 2mm styrene tube and the wires. I use 0.5mm wires that fit between the tube and the rod. Sand the tube a bit to get the edges round. Getting the wires into the gap isn´t that hard with a little practice, use a superglue but don´t forget to spread the wires into a spider to keep the glue from running up the open wires.

After the glue is dried you can cut off the prodruding wires. Insert that little tube piece for the coil line.

To simulate a cap I wrap 2 layers of 1mm masking tape to the top end and then paint the cap black. Behold a distributor.

Pulley time! This engine needed an alternator and fortunately I found one in my boxes (not the finest one, but I satisfied for it). I attached it to the block with a 1mm brass rod and glued all the pulley wheels to the block. The engine also needed a fuel pump, which I added to the front (built with pieces of styrene tubing).

The belts are made of 1mm synthetic rubber sheet. I´m still looking for something thinner but have not found yet. Even bicycle inner tubes are 1mm thick. I cut a 0.5mm strip for the alternator and fuel pump and a 5mm strip for the charger. While moving on I enhance the pulleys fronts with tiny photo etched hex nuts.

Now I connect the fuel lines. For cable and line ends in general I have become fond of beads. Yes, little glass or metal beads. You can get them in craft stores, but it´s hard to find the REALLY tiny ones, meaning 1.5-2mm diameter. Those smallest ones often come from Japan and I take every opportunity to visit new craft vendors to check their variety. In this case I thread them onto braided lines. Comes very close to those heavy duty connectors you seen on hot rods or drag racers.

Now it´s time for the ignition system. The holes in the cylinder heads I fill with pieces of heat shrink tube that I found at a model fair. (Yes, shrink before inserting...) You can probably get it from electronic suppliers too. The thinnest size shrinks down to 1.6mm with a hole big enough for a 0.6mm wire.

Here you can see the finished setup with the coil and also the a part of the throttle system.

Attaching the heating hoses comes next. I´m not sure yet how the cooler will look like one day but the hoses are long enough to fit. And last but not least the exhaust manifolds. They received some hex nuts also.

So, I hope this didn´t bore you. I will not say that it´s all easy, but a matter of time and lust. From all I can see in this forum, there is a lot of workmanship out there and I might have inspired someone to try this out, or maybe parts of it. Some details get lost once the engine is dropped into the bay, sad to say. But I love work like this.

Thanks for watching and now the finished engine:

 

 

 

 

[espo]

Looks great, especially considering the lump of an engine you had to start with. 

[FLHCAHZ]

Fantastic!  very lifelike.

[cheyenne93]

AWSOME DETAILING!!???

[NOBLNG]

Nice work and a great tutorial. What do you use for chrome paint on the pulleys?

[Andy Oldenburg]

Thanks for your kind response! Yes, the engine was a bummer I didn´t want to use in a model, but didn´t want to throw away either. The chrome work is with Molotow chrome markers, which come very close to the original thing. I use 2 and 3mm markers. The scoop had very bad mold edges that had to be sanded off, with the chrome gone too. The 3mm Molotow was good for this "big" surface. For the finer parts I use the 2mm directly or I pump the tip on my table to make it leak a bit. I take up the paint from the felt tip or table with a fine sable brush. Molotow also offers 1mm pens, which I cannot advise. The tips dry out easily or they will burp out a blob of paint while your doing your detailing, very aggravating! They also offer liquid chrome, that you can even airbrush with a 0.2mm nozzle. I met a guy who masks his whole model and does the body chrome work with an airbrush. The shine does not compare to bare metal though.