Sunday 30 August 2015

y = ax^2 + bx + c (or in other words, Algebra!)

Hello all, I'm Roger Harris - new to the club and to slope soaring. I did a fair bit of power flying around 15 years ago but found it a bit 'samey' after a while. I needed something with a challenge and a goal - soaring seems the ideal thing!

I started with a Multiplex Cularis - good fun but a bit fragile to fly off the slope (especially when one's landings are less than optimal...). Then Rob S. kindly sold me the Stargazer - much better but still breakable! Finally along came the Spectre. Somewhat tatty but almost indestructible. So I've got a nice stable of models for the slope.

On the thermal side, I had nothing other than the Cularis. Paul H., however, had a couple of big boxes hanging around which he wanted to move on, so I bought them from him. They comprised of a full kit for an Algebra 3m thermal soarer, a glass fuse of unknown provenance and another set of wings and tail, various other oddments.
Exciting prospects indeed!

Finally I got a chance to sort it all out and indeed there's a full Algebra kit. The glass fuse is something called a Diamond, from Clive Hall Models. 

I plan to build the Algebra first, as standard, then the Diamond with straight wings, single dihedral and a mid- or T- tail.

After this morning's great meet-up at Ditchling Beacon, I came home enthused - a 3m Algebra would've gone beautifully in today's conditions. Of course, once I get it built we'll be into Winter and constant 50kt winds... ;-)

The first thing to sort out was a building board. My workbench, being made out of recycled pallets, is not level in either direction so I built a board, which I lay on top of the workbench, with tapered battens on each edge to bring it level and keep it flat. A flat and level surface on which to build is vital for a straight aeroplane and it's worth the effort to get it right. I actually checked mine with a spirit level!
Here you can see the building board with the first few wing components ready for assembly. The board itself is plasterboard over a 12mm chipboard base, all kept square and straight with 3/4"x2" battens underneath.

On the left of the photo above, you can see a small paint brush and a plastic pot towards the back of the board. I watered down the PVA glue slightly to allow me to apply it more thinly, then painted it on with the brush. A thorough rinse with tap water after use means both the pot and the brush can be re-used.

Note I've laid out the components in handed pairs - less chance of making two left wings that way!

The parts shown are for the wing-joiner boxes. I carefully sanded down the parts to remove any traces of plywood release-agent from the surface, then glued together the first two bits of each wing box:
Next will be the second ply web seen at the top of the photo. After that, I have to cut the slots in the foam wings. Eeek! Not done that before!

I'll try to keep you all posted if interested. Any comments and advice will be welcome.

Cheers for now,

Roger.

5 comments:

  1. Hi Roger, that board looks the dog's wotsits - we now expect the best ever models we've ever seen in the club !!!!! Just to set you up a challenge !!!!

    ReplyDelete
  2. Awesome set up mate. Looks like you'll not run out of things to do this winter! Look forward hearing how you get on with the builds. May be a while before I contemplate another!

    ReplyDelete
    Replies
    1. Thanks Will, the Algebra and the Diamond should keep me busy for a while, but I'm already thinking of a Coroplast PSS jet for afterwards...!

      Delete
  3. Haha you're unstoppable! Good on you mate. A PSS jet would be wicked!

    ReplyDelete