Thursday, 14 January 2010

Shooting Board - The Ramp - Part 3

The third in this series is a focus on the Adjustable Ramp for this pie-in-the-sky Shooting Board I want to build.

To even out the dulling of the plane blade, I like the idea of a ramped runway. The bonus of this is a skewed blade. What I don't like is the idea of either having to live with the ramp in all applications or having to make two Shooting Boards. Hence the Adjustable Ramp.

Here is the results of my efforts to come up with something that is workable in all configurations...

My grade 5 math teacher taught me that any angle divided into two can be made into a right angle by flipping one section, so I applied that theory to this ramp. First I defined the heights to have the bottom of the plane blade strike the stock just above its lower edge at the start of the runway, and did the same for it at the Shooting Board's fence. This gave me the angle. I then completed the piece by giving it a flat bottom. I then divided it into two equal pieces.

As the plane is going to run in tracks, it means that the top piece requires two sets of them; one set for the plane to run at the angle, and another for it to run when this piece is flipped to produce a flat runway. This meant I had to find the sweet measurement that would allow enough stock to let the tracks into both top and bottom surfaces, yet keep the Shooting Board's height to an absolute minimum. The result is an overall height of 4 1/2".

I'm still searching for some hardware that will allow quick, but solid assembly and disassembly. There must be something out there.

So this is the basis of the project, which still needs some fine-tuning before any wood is cut. If anyone has any comments, observations or advice, I'd love to hear it.



1 comment:

  1. Hi Mitchell - I've had a quick gander at the proposed plans for a 'shute to end all 'shutes and they certainly look impressive.
    However, if I could offer one or two points from a personal perspective...

    Firstly, these are essentially fairly simple 'shop jigs that ought to be able to be knocked up fairly smartly from odds n'sods knocking around the 'shop...for my money your proposals look far too complicated...simple is always good.

    I've used a ramped 'shute and it's a strange experience, a pal in Weymouth who has one reckons the standard type as shown in my blog works better, or is easier to use.

    The other issue that I could see that would worry me is the scissor jack arrangement for the mitre jig...I would question how many times you'd need to shoot anything other than 45deg%, probably very rarely. Also remember that any errors in the set up of that jig are multiplied twice at each corner and eight times (if my maths is right) around the perimeter of a box.

    The long mitre jig that I made was a fairly straight forward affair just biscuited together, the only essential thing is another mitre 'shute to make it and a really accurate 45deg mitre square to check for accuracy.

    I hope you don't mind this discourse too much and I haven't 'rained on your parade' unduly.

    Best - Rob