Page 5: Making the curved bracing members
Marking the curved members
Each curved member will need to be cut from a piece of 1 1/2" x 9 1/2" (240mm x 45mm) wood that is 48" (1200mm) long.
You will need eight curved members altogether, two at each corner.
To cut the curves, a bandsaw or similar tool is ideal.
However, it is possible to cut the curves with an ordinary circular saw, as explained in the section below.
Or, don't go with the curved members
Alternatively, you can use straight pieces of 1 1/2" x 3 1/2" (90mm x 45mm) wood fixed diagonally.
It will use less wood, be cheaper and still look good... just not as good as the curved stuff!
OK, moving on.
If you still want to cut the curved members, first, mark out the curve.
Bang three nails into
a piece of 1 1/2" x 9 1/2" (240mm x 45mm) wood that is 48" (1200mm) long,
positioned as shown in the drawing below.
Bend a length of rod (or anything that bends evenly) between the three nails, and pencil a curved line
against the rod.
That marks the outside edge of a curved member.
Use a piece of wood the same width as a framing member, as a guide to mark the inside edge.
Once you have cut the first curved member, use it as a pattern to mark and cut the rest.
Cutting and fixing the curved members
Ideally, cut the curved members with a bandsaw, however if you do not have a bandsaw or are unable to get the use of one,
then it is possible to cut the curves with an ordinary circular saw (after all, I did)
you do need the right saw, and also you will probably need to tinker with the blade.
The radius of this particular curve probably just falls within the boundaries that enable such a cut to be made.
Not any old saw or any old blade will do it.
You will need a saw with a bit of grunt, and with a blade size 7 1/4" (185mm) diameter max.
A blade that is any bigger will make it difficult to cut the curve.
So in golfing terms, a bigger blade just won't make the cut.
You will also need to reset the teeth of the blade
so that they bend out more, meaning the blade will make a wider cut, thus allowing the saw to turn easier.
By default, the tips on tipped saw-blades point out in alternating directions, and the tooth ends on un-tipped saw-blades are bent outwards (set) in alternating directions.
This is to obtain a kerf (cut) that is wider than the thickness of the blade plate.
Our objective is to make the kerf (cut) wider by bending the teeth further in the direction that they are already leaning.
You can bend the teeth easily enough, just by resting the blade flat on a workbench with the teeth overhanging. Then, grip a tooth with an adjustable spanner or a pair of
pliers and exert a bit of downward pressure.
It does not take much.
Do every second tooth and then turn the blade over and do the same to every other tooth.
Make sure you bend the teeth the right way: the teeth are already set slightly one way, and that is the way you must continue. Of course, once you have done this, the blade won't be much good for anything else, and should be discarded.
If the blade is set right, it should cut the curve as easy as cutting a straight line.
If you have to struggle with the cut, then something's not right.
Make sure the wood is clamped or secured firmly.
Make sure you have stable footing and are fully in control of the saw. Wear safety glasses.
That said, go and cut eight curved pieces, all of which are slightly over length at this stage.
There will be two for each end of all four wall frames.
There still needs to be four more smaller curved pieces cut for the top of the front and rear frames,
but they can be cut from the off-cuts of the previously cut curves.
They already have one curved edge cut, so they will only need to be cut on one side.
They are also not as long and only four are needed altogether, two for the front wall
and two for the rear wall.
When all the curves have been cut (at this stage they are over-length), sit them in position on top of the wall frame, mark the ends of the curved pieces, cut them to length
and fix them in place.