mills 1.3cc diesel mikes-models

2nd March 2008 session 15

I set the top slide over to the required three degrees and after measuring how
much had to be taken off both the front of the case itself as well as the area
to be turned down. I then spent the next hour doing what a more
experienced engineer would take perhaps 20 minutes to do. The reason? I
checked, rechecked and checked again after every light cut taken on the
taper turning and using at first the sharp tool I ground earlier, must have
taken 15 or more cuts to achieve the correct dimensions (see photo a). Just
in time I remembered that there was a radius to turn where the tapered shaft
met the face of the crankcase, so I had to grind the nose of the tool steel I
was using to make the correct radius.

After completing the turning on the lathe I next completed the plug that needs
to secure the crankcase to an angle plate which in turn will be fixed to a face
plate. This required me to part off the plug used yesterday and mill off 0.192"
from one side (see photo b). As I have only recently had the large variable
speed lathe, I have never used its faceplate. This will be required for the next
session so I thought I would finish the session by getting ready for the next.
And what a job that turned out to be. Indeed I nearly gave up and thought I
would have to use the ML10, something I did not want to do really as Its a
small lathe too swing the angle plate around. Or that's my fear/view really.
The first problem I had was working out why the studs that accompanied the
face plate were so long. When offering it up to the nose plate they not only
were too long but it would not seat correctly. I then remembered that the 3
jaw chuck I had just removed sat against a spacer. So I removed that and
then could see that the studs went through both the faceplate and the spacer.
I wasn't convinced as I thought with no clearance holes it wasn't guaranteed
to get it to fit flush. And so it proved the first time I put it on the lathe. I didn't
need to use a dial indicator to see the face plate was out.

So I took it off again and using the magnifying glass could see it wasn't sitting
flush on one stud. So I removed the studs and tried again. I kept the first stud
in reasonably tight enough to hold the plate flush but not tight enough to stop
the other studs from finding there place. When putting it back on the lathe it
was much better but certainly not running true enough for my likening.

I then decided on an extreme (to me...) action of taking a cut deep enough to
get under the cast skin, on the face plate. It would certainly run true then!
And all was working well for about three quarters of its diameter (starting at
the centre) with a good facing cut working well. However, as I got towards
the outside the skin seemed more difficult, with the tool riding over the face. I
don't know whether this will be classed as butchery or something you should
do.........someone will no doubt email me so thanks in anticipation......For all
that it worked enough for the area I will need for the angle plate I am going
to use. I realise I can't leave it like it is however as the three quarters of the
face plate form the centre, is now not flush. What I have considered is to mill
the skin off then take a cut across all the face plate. Anyway, back to the
Mills crankcase, the next session will deal with the boring out of the
crankcase for the cylinder insert to fit in. The main success of the session was
getting the crankcase to the dimensions required and not turning it into scrap,
and that is a big big result! So far so good..............

Time spent today 3 hours 30 minutes. Total to date 30 hours 30 minutes.