Hi Guys - thought I'd better give you an update on what I've been up to. (I did this last night but just as I previewed it the site went down - fortunately I'd just saved it - phew
As previously mentioned I intend to board in the flywheel which is in keeping with full size practice of an engine of this stature. I've decided to make that boarding fit a rebate in the rim and be held in place by the pressure of the hub plate. Doing this on the outer side is not an issue but the crank side would mean either the hub being captive or, as decided on, split in two and held together by a ring and cap.
First up, having drawn it out, was to produce the boards - 60 per side. These were cut from 0.8mm three ply left over from model aircraft days.
The ply was cut across the grain, the width to just over the length of a board, and a simple jig made using a piece of white faced particle board. Two strips of 1.5mm ply were super glued on it, spaced to retain the ply, and a metal guide strip set at 3 degrees screwed in place.
The 120 strips were cut off using a scalpel turning the ply over each time to create the 6 degree tapered boards.
Wider than finally required these will be machined to a true angle and width at a later stage but this gives an idea of the hoped for effect
A sub-plate of white faced particle board was bolted to a large faceplate and the ali discs cut out on the bandsaw.
A 6mm dowel locates the centre and twelve screws outside of the finished diameter required hold it firmly in place.
Due to the anticipated 'claggy' nature of the ali sheet a very sharply pointed tool was ground to trepan out a 30mm dia central hole...
....which is to take an insert that will locate the inner point of the boards. The board was also engraved on the lathe at the four quarters to act as positioning guides for the first four boards
The hubs began as silver soldered components, one 2mm larger than the other
Once turned the larger one was cut in two on the centre line and the faces lapped flat and cleaned of burrs.
This was then soft soldered together .....
.... then the two subsequent high points created by this were carefully linished off to enable initial holding in the SC 4 Jaw
Both were turned to the same dimensions with the split one having a register for a clamping ring. Once finished this was heated to break the join
The parts ready to fit (the hex head bolts are temporary - it's intended to make square head ones)
.
That's the current state of play - next up is to make a fixture for holding the boards to machine them and get them stuck in place. This is all new territory for me but I feel fairly confident this will work out - that's put the kiss of death on that then
It promises to be a nice day tomorrow so will be digging over the dhalia beds.
Regards from the old shid - Tug
