Having completed the first Seal camshaft you can imagine my bitter disappointment when checking the profiles against the plans to find that they were miles out! No matter how many times I looked at them, turned them around and even when stood on my head, it wasn’t right!
I rechecked the methodology; re read Steve Huck’s article, to find out where I went wrong but all to no avail. The camshaft looked nice, but looking nice was not going to cut the mustard for a successful engine build, let alone the two Seal engines I am making!
When I couldn’t make any further progress in finding the answer I emailed Steve Huck and after many, many, emails, photo’s and explanations we came to find the answer.
Steve makes it perfectly clear in his article (reproduced on this website, by kind permission of Steve) that when making the cuts you turn the camshaft 5 degrees AWAY from you, i.e. clockwise. So what did I do? Well I thought that moving the cam 5 degrees towards me would make an easier cut and my 360 degree wheel had two scales on it (see photo). So when I made the 270 degree cut I should in fact have been making the 90 degree cut! So in fact I was 180 degrees out.
To make sure no one else makes the same mistake Steve has amended his cutting chart (see downloads) including a portion of the 360 degree wheel he uses, and makes it even clearer that the cut must be AWAY from you. Not that he didn’t say it clear enough in his article, no the fault was all mine. You may think this shows me up more than a little, well you would be incorrect to think such a thing.
Indeed it only goes to show my genius! Why? Well the two engines I am building will run contrary to each other so one needs in fact to run backwards. When analysing the pattern I had achieved Steve emailed me to say that the camshaft I had made was exactly what was needed to run an engine in the opposite direction.
So in fact what you may think of as a mistake was in fact planned on my part………….. to make the second engine work…….tee hee…
So now I can make the two ‘proper’ camshafts with confidence. After all the research, and with the help of Steve to find out what happened to produce my ‘special’ camshaft, I have a far better understanding of a subject I thought I knew something about…….In the end, a good outcome.
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!
