Quantumstate’s Blog

Quite a few years back before I moved house I decided to draw up some plans of my house. I walked round the outside with a tape measure and recorded all of the distances and then drew then up to the scale of about 1:76 which is 00 gauge for model railways. I have a small railway layout which is nowhere near finished and has laid abandoned for a good while at this scale.

A while after drawing the plans I decided to actually try and scratch build the house, scratch building was obviously the only possibility since there is not a kit, also the house is a fairly unusual shape so a conversion wouldn’t work.

I started off by buying a bit of brickwork which is embossed plastic. I soon set about cutting this to shape which wasn’t the easiest of jobs since the tiles I had bought, although very nice quality were about 1.5mm thick which makes it difficult to cut out small windows with a craft knife. It hasn’t come out too badly and hopefully I will be able to disguise most of the bad points with a bit of paint and some filler.

At this point the work stopped for a while since I hadn’t ever actually made a building at this point, not even from a kit so I got a bit stuck, having no roof and the prospect of trying to glue together these rather roughly cut pieces of plastic wasn’t inviting. I have since trimmed the plastic into a somewhat better state.

Later on I visited the Warley National Model Railway Exhibition which was very good. Here I saw a man who had created some wonderful buildings in 0 gauge which is a bit larger than 00. I took most of his ideas and am using them to build my model.

For the main structure of the house foam centred board is used. This consists of foam sandwiched by a piece of card either side, making it very light which still remaining rigid and fairly strong. This is fairly easy to cut with a craft knife although it is harder than you would think to get it nice. It definitely looked easier when the man at the show did a demonstration.

I pinned and glued this together which formed a structurally solid building. I will be able to stick the brickwork onto the outside of this later on in the process.

Importantly this structure gave me a base for the roofing tiles. I again used the method shown at the show which is; to take paper/card depending on the scale and then cut a series of slits the right width for the tiles. I used graph paper from an old exercise book which was fairly thick paper and the graph paper is excellent because you can see how far apart the slits should be. You then cut off a strip with the slits on one side and a solid strip on the other so you can pick it up as one piece.

Then you can simply lay the strips on the roof, starting from the bottom and overlapping them so that only the slits are shown. This creates the proper effect because this is how tiles are laid on a real roof. The first time I tried this the lines kept going wonky so I scrapped the area and stuck graph paper over the entire roof which now acts as guidelines to keep it horizontal and maintain proper spacing.

This process is time consuming since a lot of little cuts need to be made and they must also be laid carefully onto the roof making sure that they are straight. I am in the middle of the process currently and have about a third of the roof done and probably about enough strips cut to get me past half way. After this is done things should quickly progress to the stage where I can paint since the tiling is already cut to shape.

Here is a picture showing the model, The garage is missing form the near end which is why there is a gap. I found that since it is connected via a narrow strip it was better to work without it attached.

I have taken a video of the trebuchet that I talked about in this post. I also have a few more pictures.

This is the path that the apple took. I have merged together several frames of the video and highlighted the apple in each one. The path looks a little odd because of a combination of a strange camera angle and the apple bouncing off the wall.

Here is what is left of the apple that was big enough for me to pick up. Some other apples were completely destroyed.

This two pictures show the joints in greater detail. Notice the reinforcing metal rings.

Recently our chemistry teacher said that if we wanted to bring in a lighter we could rather than having to wait for the matches. Never wanting to just follow the crowd I remembered a little project I had made a while back.

It was a little thing made with a film canister which you sprayed a little aerosol stuff into and then it had a couple of wires stuck into the canister which I then sparked by attaching them to part of an electronic cigarette lighter.

I took out the part from the lighter and stuck it into a pen and taped it up securely. It makes a nice spark across the gap and a benefit it has over a conventional lighter is that you can give people a small electric shock which is fun. here is a picture and a video of the thing.

The video isn’t that great. I had to do it in the dark so the spark shows up clearly and it is hard to hold the pen still because you are pushing down to get it to spark. Also the camera missed a few sparks because the frame rate was too slow.

I little while back I thought it would be pretty cool to build a trebuchet so I built one over a few days. It was actually pretty easy to make. It is basically constructed from two A frames attached together at their bases and then a long arm is attached to a pivot at the top of the A frames. The weight goes at one end of the arm and the sling goes at the other end. The weight falls and so the other end goes up and flings the projectile. This makes it pretty cheap to make which is an important consideration with my projects. I think that the total materials cost came to about £8 which was spent on buying a metal tube, a length of bolt and some nuts. The tube and bolt came in 2m and 1m lengths respectively so I still have quite a lot left over. I had the wood lying around as well as the weight so they didn’t cost anything.

Here is a picture of the trebuchet. It is not great because it was a little dark so it had to be taken with the flash. Also I had to hold the camera which means that it is not in the position you would fire from. The arm that is vertical is pulled right down to the ground so that the weight at the bottom is pulled up. It is about 1.8m high to the tip of the arm.

The range seems to be about 35-40m but it is hard to test since our garden isn’t 35m long so it has to be fired across the road so I don’t want to do it very much. I have fun lobbing stuff at the wall of our house though. One slightly rotten apple was completely mulched and ended up all over our drive.

Here are some pictures of the different parts of the trebuchet:

This is the frame. You can see how simple it is. The axle for the arm goes through the two holes in the cross pieces and I use nuts to keep it there.

This is the arm. You can see the end of the sling on the right hand side. I added a joint on the weight end. This makes the trebuchet more efficient because the weight drops in a straighter line. This also reduces the rocking of the trebuchet after firing. The axle is well reinforced because this is where there is a lot of strain. I have screwed a piece of wood onto either side to help stop sideways twisting. There is a piece of metal tubing in the hole. This stops the strain as the axle twists cutting into the wood and damaging the hole. This effect could quite easily wreck the axle since as it got worse the damage would increase due to more wobble. All of the moving joints have this done to them. This is the reason for the metal tubing. It also reduces friction since metal is sliding against metal.

This the weight. It is 28lbs (12.7 kg for us who like metric) which is fairly heavy. I originally used a couple of bricks but that wasn’t very impressive and luckily I found this at my gran’s house and there wasn’t any other use for it. I take it off the catapult when it is not in use because it is pretty heavy. It is attached by bolting it on, the bolt goes through under the bar on it and is annoyingly fiddly to fit.

This is the sling. Sorry the photo is a bit out of focus I will try and get a better one sometime. Basically the projectile (rotten apple) goes into the sling part and then the other end of the string is hooked onto the nail on the end of the arm. The angle of the nail is very important since it sets when the projectile is released. As the sling whips round it reaches a point when the loop in the end of the string slips off the nail and then the projectile is released as the sling straightens out. The sling method for a catapult is better in my opinion to something like an onager where there a sudden stop which makes the projectile fly off and makes the whole machine kick back like an onager (like a donkey) and hence the name.

The part that I haven’t photographed is the plank of wood that the projectile slides along at launch. The sling lies flat along this plank and then is pulled along it as the arm moves round, until it is lifted up. All the plank does is provide a smooth low friction surface.

I would recommend building a trebuchet yourself since they are great fun to play with and are very easy to make. All I used to make it was a hacksaw, screwdriver, pencil, ruler, needle file (for when I sawed through the bolt, to smooth the cut) and an electric drill. Most people would have these other than perhaps the needle file, and you could probably manage with the hacksaw since you just need to make sure you can fit the nut onto the bolt by removing the burr from the hacksaw cut.

I will try and get a video of it working some time and I will post it as soon as I do.