Building the Arden Super Atom from castings updated 28/05/2012
In May 2012 I purchased a set of castings for this engine from Ebay for just under £11. These castings are magnesium and very fine die castings. This wasn't an engine that I had planned to make but the more I researched it the more interested I got. I had some good advice from Ron Chernich and Ken Croft (two of the Motor Boys) Ron also put me in touch with Eric Offen (another Motor Boy)who kindly offered me a set of plans.
There is a page of information about this engine on the model engine news page here.
I have ordered the fuel tank for this engine from Woody Bartelt and I now have a set of drawings (thank Eric)
I will keep a blog of progress here.
The tank parts have arrived from Woody Bartelt and I now have a set of drawings (thank Eric)
My first task is to use the drawings to produce a 3D model of the complete engine. This will give me a really good insight into the complexities of the machining and also be a source of information for the jigs I will need to make.
I have now modeled the major parts of the engine and this has shown up a number of missing dimensions and a couple of incorrect dimensions. I still have to model the timer and the tank.
The exploded view of the engine
The engine CAD model is nearly complete
This is the timer assembly
Having completed the CAD model I have found a small number of missing and incorrect dimensions. I do plan to do a set of drawings for my own build but, here are the changes and updates that I have penciled on to the drawings that I have.
I have also made a couple of minor changes to a couple of components to simplify manufacture. I have replaced the 2 semi-shears used to locate the front spring with riveted on parts so that I don't have to make special tooling to punch the semi-shears. I have replaced the insulating parts that consisted of 2 washers and a bush with 2 tophat bushes.
Drawing SA-011A CAM ARM: Dimension now 0.132 was 0.100 & Dimension now 0.250 was 0.275
Drawing SA-006 CRANKCASE: Missing dimension for end of throttle valve face should be 0.322 (from 3D model)
Drawing SA-004 CONROD: Angle now 115° was 114°. angle now 125° was 122°
Drawing SA-003 SUB-PISTON: Dimension now 0.226 was 0.290
Drawing SA-001 CYLINDER: Missing diameter at top of cylinder should be Ø0.70 (scaled from drawing)