Hi guys, Thanks as usual for looking in
I don't have to go far Bertie - haircut in the kitchen then straight out to the workshop
Per, nice to see you here
the diesels are original ED 3.46 Hunters, one needing a new spray bar the other just a clean before it's first run for over forty years
There are two 5 cc versions in the pipeline, cases are done so maybe get on to the rest in the New Year.
Thanks for your kind remarks Bob and for putting the current situation into perspective - I have a feeling you may be hearing from 'Delta Tango' at some stage
I have the eccentrics fitted and working at last Phil - not sure if the following will help as I'm sure you will be following full size practice given what you've done so far.
After a lot of thought I decided not to do the eccentrics as drawn for just one reason - that of being able to get a reasonable size nut within the cut out. I considered a two stepped bolt coming in from the back so that the major part would provide the grip and the thinner part the means to fit a smaller nut but trying a suitable sized nut it looked ridiculously out of scale. Besides I really did not want to have to have two gaps in the raised portion that the strap actually rides on. With the fact that I want to display this more as a working model than as one as scale as possible, the opt out to use the conventional, one grub screw fixing, hidden under the strap was easily decided upon.
The strap blanks had been done a while back - two slabs of cast, face and milled square then drilled to take two long fitted studs to keep them in alignment.
These were held on a face plate and bored before mounting on an expanding mandrel to face to thickness. I found this unused mandrel lurking underneath the lathe bench, it must have been there twenty plus years since I made it - at work, along with many others, from scrap bits of steel and hedging against the day when the opportunity would no longer be there. It's the last one
Once faced the straps were set back on a small faceplate (a 6 inch disc of MS held in the three jaw) and the groove for the 2mm x 2mm rib cut in.
The eccentrics were turned from EN1a -the ideal wearing combination with cast and the outer diameters cut so that the wearing surface was the outer diameter of the rib. The straps were tested for optimum fit as the final cuts were made
The eccentrics were then held in an ali clamping plate for putting the bore in. By using a clamping plate for this op the correct throw is easily established by setting the clamp bore to run true then introducing a spacer (drill shank) between the clamp and stop to give the throw. (The drill has been removed but the gap can be seen 'tween stop and clamp)
Still in the clamp it was transferred to the R/T for milling the cut out using the same means- first the outer radius against the stop...
... then the second inner radius with the spacer in place
The finished eccentrics with the embryo straps
The straps were set up on another small adapter plate for milling the profiles...
.. .and the side relief
Just realised I still have some more pics to upload - too late for that tonight so that will have to do - I need that beauty sleep
Back soon then - sleep tight
Tug