Sunday 23 October 2016

Chapter 3: What you plan and what takes place...

... ain't ever exactly been similar.

I did say this wasn't going to be done in a few weeks, but this is taking the wossname.

The drawings were supplied to me in two formats. There is an A2 sheet with drawings of the Main Body and Neck side profile on one side and the Key Chest on the other. The rest of the drawings are on A4 paper in the back half of the book. Some of the A4 drawings are just construction diagrams, some are full size, some half size, and one drawing is an odd scale but does show dimensions. So I set about scaning the drawings and resizing those that needed it so I could go out and get them printed for me.

First lesson.
This might come as a surprise to you too, or just make me look stupid but...
What's twice the size of A4 paper?
Did you say A3?
Well your kind of right, but definately wrong when it comes to this project. A3 is equal to two sheets of A4, but if you want an A4 drawing twice the size you need A2.
Come again?
A3 is twice the area of A4 but, to make a drawing twice the size, you need the width and height to be doubled and that makes the area four times greater, hence A2.

After two trips to the printers I now have copies of all the drawings at the right size to begin doing some woodwork. (Yes I know that Mr Åhker said 'Please don't make copies' on his drawings but I find it much easier to transfer them to the wood that way and the copies will be destroyed in the process). I have now started to cut out the drawings and use these templates to trace the lines on to the blocks of wood.

This leads into the next step of actually cutting the wood. Apparently a bandsaw comes in handy. So I spent some time searching the internet for something cheap but good quality (yes, I know you get the quality you pay for, but I'm not made of money). I settled on a Scheppach Basa 1. It's not too expensive, has very good reviews, and is just big enough to cope with the work involved.
Having ordered and awaited the arrival of my bandsaw, and then spent most of the morning putting it together and setting it up, I finally started cutting wood today.
Now, before you start geting all excited, I will point out that this was just a practice run. I haven't used a bandsaw since I left school and didn't get much practice then either, so I didn't want to rush in with the expensive tonewood straight away. Luckily where I work we get a lot of reasonable quality scrap wood so I aquired a piece large enough to be a stunt double to the real thing and had some trial runs. The picture shows the stunt double with the correct curves for one of the Main Body sides although the straight runs have been shortened so I could concentrate on the curves. I have found two things that need to be taken into account.
1. Some of the tighter curves need some extra cut-ins to get the blade round,
2. The saw will happily cut through pine like a knife through butter, but it does chew rather than cut if you try going too fast. If you go at 1mm per second you get a very nice cut edge that won't need much sanding, but you can go at 2 or 3cm per second and get rough saw marks on the cut.
With those noted, it now looks like we're good to go.

So, if nothing else unexpected turns up, next time I could be cutting the real thing! Won't that be a surprise. There's just the small matter of an A-Series engine needing a new camshaft looming in the mean time (I did say there were other projects on the go).

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