mrrrk.net

Yet another narcissistic load of old cobblers that no-one will ever read.

The Christmas Clock

In our road, we have an annual advent calendar where alloted households display a number in a chosen window and on that December date unveil an illuminated, Christmassy display. We were allocated 14 and Elspeth suggested a clock face with a mouse staring up at it...

Twas the night before Christmas, when all through the house
Not a creature was stirring, not even a mouse;
etc.

This is an account, perhaps a bit laboured, of how the clock was made.

Clock Face

The first thing to do was to track down a clock mechanism with some big hands as that would dictate the size of the clock face.

The next task was finding an image I could use for the clock face numbers. I found one with a Google image search and removed the hands from it using Paint.Net (a very good and free image editor for Windows). I needed to blow the image up without it getting all blocky and pixelated so I used an online tool to convert it to a vector (.SVG) file.

clock-face

I still needed to print it out to the correct size but I decided to wait until the 750 mm diameter acrylic (Perspex) sheet I ordered arrived. This was the expensive part!

I tried using Word to print the enlarged face but that didn't work too well. In the end I used Big Print (https://woodgears.ca/bigprint/) which was exactly what was needed since it allows to you to print it out on several A4 sheets which when stuck together come out at exactly the size you want. After trimming the margins off and taping it all together I was able to check that it matched the acrylic disc. Bingo. First try.

Body of the Clock

I planned to use either thin MDF or hardboard for the back. A visit to B&Q revealed they had white-faced hardboard, which was cheap and would save me some white paint so that decided my choice. Unfortuately they don't sell it big enough to cover the 750 mm face - so I had to fix two pieces together with a wooden batten. The plus side of this was that it provided some stiffening and a solid(ish) part to hang the complete assembly by.

The hardboard back and acrylic face were fixed together with M4 x 20 mm nylon spacers and M4 nylon screws. Acrylic is easy to drill but also very easy to crack! It's normal to drill smaller pilot holes first and/or use a centre-punch for accurate positioning - but both of these will result in cracked and broken part though if you're using acrylic sheet.

Lights

Of coursre the clock needs to light up; it'd be a poor do if it didn't. You can get these 12 V LED strips fairly readily on Ebay and other online retailers. I calculated I needed just over 2 metres for the outer ring of lights and possibly another couple of concentric rings of lights for the rest of the face. I went for four rings of lights in the end since I had them!

When I connected it up for the first time, the individual lights were discernable, which I'd feared and didn't want. I considered putting a layer of greaseproof paper between the lights and the face to diffuse the light more but settled on increasing the distance between the front and the back by adding another set of nylon spacers, giving 40 mm between the face and the lights. Not perfesct but definitely better. (The photo below is from before I sdded the extra spacers.)

Wiring Woes

Let's be clear, I suck at soldering. It's not that hard but it does require a level of good eyesight, steady hand, patience and skill that I'm not sure I posess. Either way, I managed solder up the connections and all seemed well. These lights have individual red, green and blue LEDs in them and you can connect a controller that lets you adjust the colour and even exhibit a variety of flashing effects. However, at this point I noticed and red and green seemed to be short-circuited together. It must've been late in the day becuase I decided I didn't care - as long as I could independently adjust the level of blueness, which I still could. I also noticed that the 5 Amp transformer I was using was getting pretty toasty - but by my calculations, 5 Amps should be (just) enough. Hmmm...

Finishing off and Installation

The last step was covering the sides so all the light didn't spill out. I wondered about gaffer tape but it wasn't quite wide enough and not very substantial. Elspeth suggested the cardboard you get left over in the middle of rolls of wrapping paper which by amazing serendipity, we have lying around at the moment, for some reason! This was a stroke of genius and worked well. I added a layer of gaffer tape over that too - for good measure - and to make it black. It was at this point, after the innards were all sealed in with tape and cardboard, that the green LEDs all seemed to fail. Sod it...

Another day. I cut off a lot of tape, prised off the back and fixed my shoddy soldering. I also concluded that the LED controller was dodgy since the green LEDs were still a problem and so I twisted the red, green and blue wires all together and ditched the controller!

The reasssembled clock was installed in the designated window early on the 14th Dec (our alloted advent date) and it worked resplendently - for about 30 minutes until the power supply overheated and took out all of the downstairs lights. This required a rummage in the garage for a bigger transformer and a few minutes later a 20 Amp beast was installed (pictured in true Heath Robinson style.)

I'm in no hurry to do this again but next time (!) I should try making the numbers with a laser cutter or a CNC router. Perhaps...

Update - I can now confirm that the 5 Amp power supply is officilly fried! And that so far the 20 Amp one is running cool and has not yet burned the house down. Which is nice.

Stoney Cove

Diving trips are a bit hard to come by in 2021 so we've been for a bank-holiday weekend trip to our local muddy puddle, Stoney Cove.

The blurriness in some of these photos is definitely an intended soft-focus effect and not just a lack of skill on the photographer's part.

Tour de Cove

We decided to embark on a complete circumnavigation of the quarry which took us an hour and fifteen mintues - and pretty much all of our air.

It's not called Stoney Cove for nothing. There was a lot of this kind of view on our circuit:

Someone had really churned the bottom up:

Pike

I'll resist the temptation to indulge in Dad's Army jokes here. Pike are large, predatory fish, with large, predatory teeth.

"My, what big teeth you have..."

Blockhouse

This concrete block house is apparently a remnant of some stone-crushing equipment built by Italian prisoners during the second world war. Now you can get a nice cup of tea here - but it's bit weak though.

Viscount Cockpit

Here lie the remains of a Vickers Viscount airliner. The plane was first flown in 1948 and last flown in January 2009 for Global Airways in the DRC (not this actual one though.)

Fish is served as the in-flight meal:

There's some weird stuff down here:

The direction of the exit is indicated for us by a helpful, previous diver:

Wollaton Christmas Lights

Went to see these last weekend. An amazing experience and all the more welcome this year. Bit crowded though.

Shoe Rack II - The Revenge

I spent some time last weekend drilling.  I'd decided to fix the sides of my shoe rack onto the front and back rails using these barrel nuts:

...well, not those exact ones, but you get the idea.  Real joiners and woodwork buffs will be turning their noses up at this point since fixing stuff together with bolts is cheating.  Well it turned out that this approach was probably harder than the glueing and dowelling but it did allow for some adjustment - and will it'll be super strong in the directions that will probably experience the most stress as the thing gets dragged about in use.

The barrel nut and bolt approach seemed to require me to drill nice accurate, 90 degree, super-straight, super-central holes.  I mentioned last time that I didn't have a drill press so my solution was to set the pieces up as straight and level as I could in my 'bench' and use the little round spirit level thing on the end of my Argos drill:

That seemed like a good approach but when I tried to get things to fit, they didn't.  I'd drilled 10 mm holes for the 10 mm cylindrical nuts but they were too snug and too shallow.  It took some effort and ingenuity to get the nut back out!  10 mm is the biggest brad-point wood bit I've got and the next size up from that is my 15 mm forstner bit - so obviously I had to try widening the holes with an 11 mm general-purpose HSS bit - and it made a right mess.  Afrer I tore out a nice big gob of wood out on one of the pieces, I decided that I'd had enough for the day.  Sometimes you just have to know when your patience is wearing thin and it's best to stop before turning your project into a complete sodding disaster...

A couple of days later I had another look at the situation during my lunch break (beween sessions, slaving over a hot computer) and I decided I could widen the holes for the nuts to 11 mm fairly succesfully without making too much more mess.  For the nuts to be central in their holes, I needed to drill through pretty much the full width of the rail but just stopping before breaking through the other side - using my finger to feel the bit starting to jiggle under the surface!  It's amazing the difference it makes coming back to what seemed like such a hard problem but with a fresh head this time.  I also decided I needed to enlarge the 5 mm right-angle holes for the bolts to 6 mm to allow a bit more adjustment and wiggle room.

I cracked on with this on the following Saturday until all the holes in the rails were reamed out to my satisfaction and I was ready to try fitting stuff together.  It was really fiddly trying to get all the dowels to all go in and I noticed some of my 15 mm holes were not deep enough with the result that the selves would be pushed out too wide.  More on that later.

Earlier in the week, I'd invested in a sander as I thought that'd be handy - and I like buying stuff with wires.  I (wisely) tried out my new random-orbit sander on a piece of scrap - and instantly knew I'd bought the wrong bit of kit!  That thing would have reduced my project to sawdust in no time.  However, I did still find a use for it:


Clamping the handle as shown, I was able to assemble a poor-man's sanding station which enabled me to very quicky chamfer the ends of all the dowels to make them easier to locate in thier holes.  It could have also enabled me to quickly lose a few fingertips too if it'd have come loose.  So don't try this at home kids, I'm a trained idiot.  I did at least wear eye protection.

Holes endeepened and dowels chamfered, I just needed to make some holes for the bolts in the side pieces to correspond with the bolt holes in the rails.  When I said earlier that I didn't have a drill press, I sort of lied.  I have one of these sort of toy drill presses you can fit your Dremmel tool into:



The biggest bit I can fit in my Dremmel is 5 mm - just big enough for this - and not much else. It made some very nice, straight holes so I think I need to get me a proper one...

Now I'm ready for the final (ish) assembly.  It was a bit fiddly but it went together much better than I expected.  Here's a close-up of one of the joints, showing one of the chewed-out holes (one of the better-looking ones) with its barrel nut nestling inside:


The final task was adding some castors to the bottom.  I just drilled some 9 mm holes and the M 10 thread of the castor just self-tapped its way nicely into the wood.

So here it is, in all its glory:

Acually, I lied about the castors being the final task.  I still need to sand it down (manually!) and paint on some wax finish.

It's not entirely perfect and the bolts aren't real joinery but all in all I'm pretty happy with it.


:o)


Making a Shoe Rack

Why am I doing this?

Elspeth (my lovely wife) remarked lately that the shoes on the kitchen floor were getting a bit out of hand and we wondered if we needed another shoe rack like the plastic affair we have in the front porch.  That idea was quickly followed by my resolution to build a wooden one.  I don't do a lot of woodwork because my past attempts have met with mixed success.  My dad was once a joiner and when I was little I was fairly in awe of his Jedi-like wood skills.  To some extent I think I naturally assumed I would somehow inherit these skills, perhaps genetically, and would demonstrate my own mastery without putting in the required effort.  Needless to say it doesn't work that way!  Anyway, this time I have an electric, circular mitre saw to help make neat cuts and a determination to take the time I need and not rush things as I'm prone to do.

So, off to Wickes to buy a load of wood.  I'm using 34mm square planed timber for the frame and lengths of Ø15mm dowel for creating the shelves.  I tell you what though, it might grow on trees but it's not cheap that stuff!  I reckon it'd have been cheaper to buy a bloody rack, ready made.  Mind, I suppose that's not the point as this will be made by me and to my specifications.

The Work

First task was setting up the fence on my cheapo mitre saw as the angles are not right as it comes from the factory.  It was pretty tricky to measure 45° accurately against the blade so I just made a couple of trial 45° degree cuts and put them together to see if they made a nice square 90° degrees.  Took a couple of goes but after that, I decided it was close enough.

After making all the mitre cuts I needed, I set it to 90° and cut all the straight bits.  I clamped a bit of wood onto the end of my 'bench' so that all the peices were the same length since consistency and precision is more important than accuracy here!