I had a great Easter holiday with both my daughter Vicky and son Adam, with their respective partners Justin and Jemma, down for Adam and Jemma’ s engagement party. Whilst it is very nice to see them it does take me three or four days to recover after they have left, so workshop time has been nil until today.
I started by trying to work out where I had gotten to with boring the second Seal cylinder block casting. Previous experience had led me to leave a note on the milling machine the last session, saying it was all set up for the next cut. However the reading on the digital readout did not match my setting when double checking everything. I do not know where I went wrong but the ‘y’ axis setting was incorrect. Looking through my scribbled note book I saw the reading I was on for the Y axis, but no workings on how I got there.
Whilst it was only a few thousandths out, it meant twice the error before getting to a round bore again. I could either go with the mistake for all 4 cylinders or make the first cylinder larger than it should be, but in exactly the right place. Since the error was contained inside the recess needed for the cast iron lining, I decided to alter the ‘Y’ axis reading to what it should be and accept that the liner would have to be slightly oversize on its outside diameter, to accommodate the error. At least it would be in the right orientation.
The rest of the morning was taken up with completing the 4 bores for the cylinder linings, including the top recess ...
followed by drilling out the top of the eight valve bores, reaming to finished size. The penultimate task involved using a 3/8” diameter slot drill to make the recess required by the valve guides. Leaving me with the final task of the day, that of milling away the side of the casting alongside the valves. I wanted to get the casting squared at the same setting as the bores for both valves and pistons, although the final finish will be carried out when the casting is held on an angle plate at 90 degrees to its present position.
It will need to be faced properly on the angle plate, after having the inlet and exhaust ports machined, along with various stud holes. However by taking a cleaning cut now, I would have a good face to make sure the casting was set up as true as possible. That was enough for me for the first session back and it is progress at least.
About Mike Freeman
Hello, my name is Mike Freeman and I am a retired Chief Fire Officer from the United Kingdom with a keen interest in model engineering, silver caddy spoons and sea fishing. I live in the pretty fishing port of Brixham, South Devon, in the United Kingdom.
I am a sufferer of degenerative osteoarthritis, which impacts on the amount of time I can spend in the workshop, and is the reason why you will see seats and a stool in some of the photo's. I have only recently added the above sentence after a discussion with one of my Doctor's from the excellent pain clinic, based in Torbay. This does affect concentration one of the reasons why I double then re-double my measurements and set ups.
Before completing nearly 30 years of public service I and my wife Sandy, owned and ran, a small restaurant in Okehampton Devon. Prior to marriage I worked for my father in his various businesses, in the early days these were garages, which he bought in a run down state, then built them up before moving on, to start again.
I took every opportunity in those early days, to work in his workshop's
learning 'on the job' rather than as an apprentice. This, I suspect, is the reason why my building various model's in the early days, turned into model engineering, when funds allowed the required equipment to be bought.
My workshop comprises one half of a detached double garage. It has a
stud wall separating the two halves and unusually perhaps, its own
shower/toilet/washbasin compartment! (the true reason for buying the
bungalow - don't tell the wife!!!)
It is fully insulated with a ceiling and fluorescent lighting supplementing the one window. Several double electrical sockets are dotted around in
relevant positions.
Equipment consists of 2 lathes (1 Myford ML 10 and 1 Chinese variable
speed motor with etched glass DRO's), 1 milling machine (RF25 far East) floor standing pillar drill, Proxxon bandsaw, Warco bandsaw, 6" wire brush and polishing mop motor, 6" coarse and fine grinder, Proxxon mini drill, various benches and an engineers vice. I have just acquired a third lathe, a Myford ML7 which I am at present evaluating so I can decide which of the Myford's I will keep.
I have only just bought the Chinese lathe and had it fitted with DRO's prior to delivery. And what a bonus they are! So good in fact that I decided to buy another set for the Milling machine. Whilst my engineering experience can only be described as limited, I find the use of DRO's has affected my accuracy levels which have improved tremendously (although that's not saying much!) and would recommend their fitting to any model engineer.
Prior to retirement I built for my son's 17th birthday a Locost car. This
was a tremendous project and a great feeling when it passed its test. The book it was based on suggests it can be built for £250. Ours was nothing special in the sense of all new parts but still cost about £900 to build!
When making a drawer for my lathe tools, I cut one of the pieces of wood too short and have to buy a new plank for a couple of quid. I’d be too terrified to work with expensive castings!
Hello Andy, nice to hear from you again. I won’t say I don’t get ‘nervous’ when working on castings. It must be some sort of fear factor! After all ist just a lump of metal…………until you have to buy a replacement :}
It just means you have to take far more care. I check, re check and get bored with myself when I check again but thats the way I seem to have to work! Still its supposed to be fun isn’t it? Keep smiling! Mike