Design and Prototype - Lesson Six

This has been a slow week, with my materials still not arriving when they should have (Thursday). At the beginning of the week, I decided to make some test pieces to make sure that the materials I had ordered would indeed be strong enough, and also do what I required.

The first test piece I made was to find out if the joinery would be strong enough to support the weight and wouldn't split in half. This proved a success so I moved on to the next test:

Above: Test piece on joinery

The next thing that I wasn't sure would work was the woven pieces, as this required the plywood to be bend at very sharp angles in different directions around the slats. To test if this would work I clamped pieces the same thickness to one of the frame jigs, and then tried to weave one strip and then two strips of plywood around them. To begin with this wasn't successful, with the pieces just continuously snapping at every weave. I then spaced the fake slats further apart, and this solved the problem on all of the weaves apart from were the seat frame was angled. After some further thinking and research I tested wetting the pieces first and then weaving them. This was a SUCCESS !!! Once I had worked this out I was in great confidence that my design may actually work, (although will need a lot of clamps):

Above: Testing the woven strips

 Next I worked on the cross pieces that would form the frame of the chair.These were made with four layers of plywood glued together. This meant that they would match the rest of the chair. To speed up making them I used PVA glue, and clamped up four at a time.

Above: Slates gluing up

Finally I cleaned and squared them using the disc sander:

Slates cleaned and square

I also decided to make a couple of other jigs. One of these was another jig for making the framework of the chair, due to the drying time of cascamite (24 hours). I used the same technique as the first jig, but to make sure they were the same I screwed them together and reshaped them on the disc sander.

Above: Jigs screwed together

  Finally I made the jig for the new "U" shaped piece of the chair. This was made by using a leg and one frame as a template to draw round on a piece of mdf.

Above: Pencil line of the shape of the jig

Once I had done this I then found scrap pieces of wood to build it up to the required height and then glued these together.

Above: Scrape pieces gluing together

 I then used the band saw to quickly remove most of the waste of each piece.

Above: Waste removed using band saw

 Finally I used a combination of disc and bobbin sander to remove the rest of the waste and smooth the joints. I finally fixed a base to the jig like the rest of the others.

Above: Jig ready just need a base

Above: Jig finished and shown with the shape of the leg