EASTON & ANDERSON

GRASSHOPPER ENGINE BUILD

Part two by Jason Ballamy

I made a start with the two crankshaft pedestals. These are basically the same except the outboard one is longer to compensate for not sitting on the engine’s base casting.


I started by machining some cast iron block to 2” x 11/16”section then mounted it on its side in the mill vice and using the ARC function on the DRO cut a ¼” radius quadrant with a querk on one edge.


And then the opposite edge.

The same process was carried out on the other edges until I had two embryo pedestals. The bases were cut to 4” long from 1 x 3/8 flat steel and drilled for mounting bolts and small discs added for a raised ‘cast’ area around the hole.


The CI blocks were then drilled and tapped so they could be screwed and Loctited to the bases. Yes, there is a place for socket head screws on period engines and that place is out of sight.


Once the Loctite had set I could locate the bearing heights from the base of the fabrication and using the boring head these were cut to7/8” dia. Note the plug gauge in the second photo used to ensure the hole matched the already machined bearings.



This work was done before I got the photos of the original from which I could see that the bearings should have had flat tops but I decided to stick with a bit of artistic licence. The tops were radiused using the ARC function again.


A ½” endmill was used to cut flats for the nuts to seat on and a 3/8” hole bored for a boss to take the oil cups. Holes were drilled for the studs, clearance down to the centre line and tapped below.


A slitting saw was used to split the blocks in two.


A bit of hand work was then required to round off all the external corners to help get that ‘cast’ look.

Followed by an application of JB Weld and plastic metal tofillet all the internal corners.

While that lot set, I machined up some 1BA studs, washers, nuts and locknuts. Finally the filler was smoothed off and a coat of primer sprayed on to see if the filler looked OK. I think it did.


See part one here     See part two here    Part three here    Part four here   Part five here     Part six here      Part seven here     Part eight    Part nine   Part 10     Part 11   Part 12   Part 13    Part 14    Part 15   Part 16