About Me

I've been taking things to bits, and making things ever since I can remember, starting with dismantling knackered alarm clocks and watches and helping my dad fix the car. Now I have a well-equipped workshop and have aquired lots of new skills, so I can make better stuff. When they first appeared, I became involved with personal computers, and these and developments in electronics have increased the scope of the things that I can do. Just recently retired, so O yes, now I can make all sorts of stuff.....

Sunday, 11 December 2016

December update

No idea where the year has gone, but it seems to have rushed off into the distance at great speed, so time to catch up on a few things that have been happenning since we got back from Oz in April.
 First thing to report, and the most important, is the arrival of young Jacob, our latest grandson who arrived at around the same time as the EU referendum (no idea if there is any connection, but there is some family precedent - I was born in 1945 and the war stopped abruptly not long after, just sayin'). He's a really good baby, almost as good looking as his grandad and we love him to bits.

 Despite all this domestic jollity, I have spent a good deal of time in the workshop. The thing that has taken the most time has been the Beast - the two cylinder 2 stroke superchaged engine that I seem to have been building for the last 99 years.

My last bit of testing managed to shear the fabricated crankshaft in half, so I set about making another one from a solid steel bar around 35mm diameter. It certainly gives a very straight and strong crank, but a real pig to machine - each journal has to be spun between centres, and because the journals are very narrow (6mm) the only tool that works is a narrow parting tool. This can only tolerate a very light feed, and gets blunt very quickly, so the whole process is sloooowww.  As the eccentric bar hits the cutter, there's a fairly loud 'thump' as well, which gets transmitted throughout the frame of the house, making this a very unpopular process with 'er indoors.

Despite the struggling with the crank, I've managed to finish the engine off, hooray!

Complete engine - front
Note the pile of clean-up rags in the pictures. I was never sure that the oil pump was going to work properly, so a) I made it a bit on the big size, and b) left the side covers off to make sure the whirly bits were going round properly. I needn't have worried about the pump, though: it works so well that everything within a 5 metre radius ended up with an oily coat after about five minutes of spinning the engine.

Does it run? I hear you cry. Well, no, not quite.  Lots of spinning with electric drills, much adjustment of timing and fuel supply, and the net result was that yes, it fires consistently with some very satisfying flames out of the exhaust.  However, it won't run on its own, and I'm not sure why. I suspect that its not getting enough fuel, as the carburettor is quite a small diameter and although this gives plenty of airspeed through it I suspect it can't deliver enough wind for the engine to fill the cylinders properly.  The other possibility is that the supercharger can't pump enough mixture to fill the cylinders, but making a new one is no small task so I plan to try other stuff first. I have made a new carburettor with a bore around double the original, but havn't yet tested it.
Complete engine - side

Why not test it?  Well, at the last attempt to start it one of the rocker arms that link the pistons to the crankshaft managed to peel itself open like a banana - I under-estimated the load on these arms (obviously) and should have made them a bit beefier.  I need to make a new one, which will need some more material, some welding, and a lot of machining. On my list for after Xmas, so watch this space..

In between covering the workshop with oil and filling it with clouds of smoke, I have made another watch. This one builds on the things that I learned from the first two, and has ended up pretty good though I say so meself.

It uses a basic quartz movement by that nice Mr Seiko, and the dial is marked using a static cutter in the mill spindle, dragged across the dial face to make shallow grooves.  After polishing, the dial is sprayed with several thin coats of car paint and contrasting colour acrylic paint dragged into the grooves with a bit of an old cornflake packet.  Then the whole dial is sprayed with clear laquer. The orange ring above the dial is sprayed with candy orange over a silver base, gives a very nice effect but spraying it with the airbrush is a major pain - it needs literally dozens of thin coats, and after each one the airbrush needs to be completely stripped and  cleaned with thinners. The thinners also seem to be eating the rubber seals in the 'brush as well.

The back of the watch is screwed on, a very fiddly job to cut the threads, but it does give a good finish to the watch. I also used a steel bracelet instead of a leather strap, not only makes it look better, its also a lot easier to put on and take off. I'm so pleased with this watch that I find that I wear it most of the time.

The dial is the hardest part of these watches, everything else is just engineering - although a bit challenging because everything is so small and my fingers are not. I would like to put some proper printing on the dial as well, but I can't see a way to achieve this  - I'm pleased to report that The Pilot can't do it either, in spite of making watches for a lot longer than me.

I have just started experimenting with waterslide transfers. I can buy A4 sheets of the blank paper, print it on the laser printer and just soak it and slide it on to a pre-painted dial.  Its early days yet, but its showing some promise.  The only issue is that the transfer material is lightly cloudy in colour, so it does affect the colour of the paint that its applied to. A couple of new watches are in the design works at present, so we'll see how they turn out.

I like to alternate between bashing metal and hacking up wood, so for a break from engineering I made a pen box for Sean. It uses a design that I have been thinking about for some time, with a contrasting gloss and satin black paint finish and a highlight strip set into the surface.

Making the box is easy, although modifying my home-brew hinges for a smaller box proved to be a bit fiddly.  Painting it to get the right finish took literally weeks, with every coat the target of stray bits of fluff or marauding insects. The highlight strips are painted in the same candy orange which I used for the dial ring on the watch, see the notes above on what a pain that is with the airbrush - I can buy the same paint in an aerosol can, and although the cans contain much more paint than I will ever need, and are much more expensive, I think its well worth it.

Its not very clear in the pictures, but the box is finished in a satin black all over, with the strip to the right of the orange accent finished in high gloss black.

Anyway, the box was finished and the last coats of paint dried while the flies were still circling for their final bombing run, and it looks great.  Carefully packed and shipped off to Oz, where it apparently arrived intact.  Hooray!
And last but not least, some electronics.  I have been interested in the whole 'internet of things' for some time, although it seems to be a solution desperately looking for a market - there's a very limited number of people who want their fridge connected to the 'web, after all.

In spite of all the hype, though, the real interesting thing to me is the availability of very small, very cheap, microprocessors with built-in wi-fi communications, which are easy to program. I've got a few of these and have been playing with them, thought the only 'product' that I've finished so far is a simple clock, behind which lies a story.... 

For many years, we had a clock in the bedroom which had a little projector to shine the time on to the ceiling, it worked just fine but eventually died of old age.  The only replacement that I could source on Ebay seemed ok, but it turned out that it had a couple of design flaws.  First, it has an alarm.  Not in itself a problem, but the second flaw is that  - despite having batteries to provide backup - the clock won't survive a power cut without re-setting to 00:00.  The alarm is automatically set when the clock powers up to go off at midnight - you can see where this is going. Power cut at, say, 2am, clock resets to midnight, alarm auto-activates and warbles like a demented warbling thing. Stumble across bedroom in the dark, hit the 'kill' button, fall back into bed.  Except that the 'kill' button is actually 'snooze'.  Attempts to stop the insane warbling by unplugging the mains lead finally exposes the reason for the batteries - they keep the warbler warbling even without any power, and the only way to stop the bloody thing is to tear the back off and rip the batteries out.
Note to self: make a box for this

So the replacement is a simple clock with no alarm, but which remembers the time even after prolonged periods with no power.  Total cost around a tenner, it uses one of these little internet of things things, so it can also update its time from the 'web if I want to write the code for it, or it can beam the time around the house to other similar devices so that they all share a common time.  I have no idea why that seems a good idea, but give me time and I'll think of something.

Next time:  a couple of new watches, and hopefully a running engine to report on, plus who knows what new stuff. Stay tuned.