EASTON & ANDERSON
GRASSHOPPER ENGINE BUILD
Part 14 by Jason Ballamy
Pistons and plumbing

Part 16 by Jason Ballamy

Conclusion - the ‘stone’ base

To conclude, I'll detail how I made the base for this engine. A few strips were ripped off an old salvaged mahogany shelf, run through the planer and a simple moulding cut on the spindle moulder but similar could be done with a router. These were then cut with the mitre saw and fixed to the edge of a 12mm MR MDF board. A "box" was made to stand the engine on and a few off cuts glued together to form the plinth for the outboard bearing block. Holes for the flywheel and pump pits were cut and lined with more MDF. Overall size is approx 450mm x 300mm (18"x12").

I had decided to go for a stone look, to simulate this drywall filler was mixed with wood glue and water, the glue helps the filler stick to the MDF and also makes it a bit more workable. Some strips of 2mm thick board were used to allow me to screed the filler to an even thickness. This was left to set up for about 30mins then as it started to firm up the surface was textured by lightly dabbing a rough stone onto the surface in a random pattern.

Then the pattern of the joints was scribed into the soft filler with the back of a snap off knife blade. I cut a few scraps of MDF to the stone size and stacked them one on top of the other to scribe each successive course. The verticals were done by eye from a marked out ‘rod’ making sure that the bond carried around the plinth.

The joints were then refined, the odd chipped corner added and any loose material lightly removed with a soft brush.
The insides of the pits were treated in the same way and the final stage was to do the paving slabs, you can't really do it all in one go as the filler will have firmed up too much before you can get it all textured and jointed.
After leaving to dry for a few days all the filler was given a coat of craft acrylic paint and left to dry overnight. The next stage is to apply oil washes, these are coats of heavily thinned artists oil colours in this case raw umber. You can see how the wash accentuates the joints and texture of the stone where it has been applied to one wall.
And here is the base after several washes, more can be applied to areas of shadow/dirt such as the pits and where the base joins the plinth. The odd stone is also given an extra wash to save them all looking the same.
And, finally, the completed engine.