| 6th October 2010
This is a brute of a casting to fit onto
the 5" lathe and to machine the main bearing recesses.
It was achieved with 6mm studding and
a G cramp to stop the short t slots from pulling out.
Note the hole into the saddle has not
been covered ...It soon was when I saw how much of the turnings went in
there. |
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| The machining did not take as long
as the setting up. The boring bar was set to make the correct cut of a radius
of 13mm and each cut was 0.5mm.
Note the hole mentioned above has now
been covered !!
|
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| So one just has to prove the work
so the main bearings were inserted and the bar which will form the crank
and all fitted nicely. |
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| The bearing caps have been made as
indicated in the second on small parts.
In the photo the bearings are in place
as are the caps.
The next stage will be to drill and taps
the lower main casting and set in M6 studs so that the bearing caps can be
bolted down when fixing is necessary.
When bolted down an M4 hole will be drilled
and tapped through the bearing caps and the bearings to make the oiler. |
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| 10th October 2010
The sides of the casting were milled
to take the width of the bearings when sitting outside the crankshaft and
the crank shaft itself was completed
(Click here to see other
section). Some additional filing away where the mill could not reach
was also needed.
I will now be fixing down the bearing
caps and drilling and tapping them for the oil caps.
|
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| As above but with the flywheel
temporarily in place. |
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| 11th October 2010
The mating surface for the upper main
casting has now been machined to datum.
The marks are those left behind when
using a relatively small slot drill! |
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| 2nd November 2010
The lower main casting was drill and
tapped to take the studs to lock down the main bearings and then they were
drilled and tapped to take the oil caps.
The photos show the set up to enable
the tapping to be at right angles to the hole and this procedure has been
used many times making the engine.
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| 3rd November 2010
Today the milling out for the timing
plate was undertaken.As you can see holding the lower main casting was a
bit of a job. Behind the casting is an angle plate that the base was brought
into contact and then packed underneath to hold to the angle plate whilst
the part was clamped down.
In fact several changes to the hold were
necessary to achieve the milling due to the size of the part. |
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| 9th November 2010
I made up a wooden template for the drilling
holes by first making a drawing in Autocad of the location and then printed
out the drawings and stuck it onto a piece of good ply.
The holes were first drill in the upper
casting and then the locations transferred to the lower casting by scribing
inside the hole.
The timber template was then aligned
and held down with tape holes drilled 5mm and then tapped M6 x 1mm.
|
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| The Upper main casting bolted down
and I was surprised with the accuracy the holes in the upper casting only
had to be eased very slightly to allow the two the mate.
The piston moves easily in the
cylinder. |
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TO BE CONTINUED
