Last year I made a hexagonal roofed bird table for the family garden and although I loved the finished result and wanted to make more to give away as gifts, the effort that went into making the first table made it impossible to reproduce except for those you love the most.
So this Instructable describes BT v2.0, a quicker and cheaper to produce bird table that looks almost as good.
What do you need?
- Plywood or other sheet material
- Hardwood offcuts, ideally oak, teak, cedar
- Wood glue
- Malleable strips for covering joints such lead or copper pipe/sheet
Step 1: Main Roof
For the original bird table, the internal structure of the roof was 6 pieces of external grade plywood cut on the edges at the correct compound angle so that they fitted together nicely into a stable form. Lovely idea but it took an age to do with final fettling of the joints to make them tight and without gaps (See Roof Compound Angle Calculations if you want to do it yourself).
Here the mantra is to take the easy route so all calculations are approximate and what scrap wood I have at hand. So I've raised the scrap bin for some 6 mm plywood and cut out 6 equilateral triangles approximately 20 cm along the bottom edge and 30 cm high.
MDF offcuts are used to make a large hexagon and a smaller hexagon. The edge length of the larger hexagon is slightly smaller than the shortest edge of the triangles i.e. 18 cm, and the smaller one has sides of approximately 5-7 cm. The edges have been bevelled at approximately 45°.
Each triangle is now screwed to the hexagons. To work out at what point the hexagons are placed, you drill simply place the hexagon side onto the triangle at the point where the width of the triangle is the same as the side of the hexagon. Mark the height for the 2 points on each triangle and drill a pilot hole in the middle. Screw each face top and bottom into the hexagons and you now have a witch’s hat shape and the hidden structure for your bird table.
Step 2: Making Roofing Shingles
Since making the original bird table, I have got a new workshop and I put hexagonal felt shingles on the roof. The thing about the felt shingles that I had not realized is that you do not get individual shingles but sheets of 3 shingles and when you overlay the top with the next row you cover up the joints and they look like individual shingles. So I pinched this idea and will be making shingles in groups of 3 but you could easily make then sets of 4 or 6 depending upon the width of your donor wood.
A little bit of maths and I worked out that each face of the roof has approximately 60 shingles so by making them in groups of 3 I will need approximately 20 sets per face and 120 for the whole roof. So now to start process of making the shingles.
NOTE: Regarding the wood to use, try to use one of the typical outdoor ones like oak or cedar but if you have nothing suitable and want to use another then be aware of the movement of some. The square prototype I made was roofed with tulipwood and as soon as it got wet the shingles swelled and buckled.
Most of the wood I am using for the roof has come from 120 mm wide oak boards so each set of 3 will be approximately 120 mm x 50 mm. I simply cross cut the boards on my table saw into strips by eye until I run out of scraps. I've not worried about any variation in width or depth because shingling by definition are always different sizes and widths.
Over to the bandsaw, I set the fence 4cm away from the blade and a stopblock clamped 3 cm behind the blade.b Now I can quickly put a cut between the first and second shingles to visually separate them and the stop block restricts the depth of the cut so you can quickly cut the 3 shingles in each block whilst keeping them attached together. Cut once until you hit the stop, pull out the block, flip it and cut the other side. There will be variation in the width of the middle shingle but so what.
Once all blocks are cut, remove the fence and by eye remove the corners at the bottom of each shingle. Once again, a bit of variation is not a problem.
Replace the band saw fence at 3-4 mm away from the blade and a set of shingles can be sliced off the block. A couple of tips; use a big piece of wood to securely hold the block against the fence and push into the blade with a push stick, not your fingers.
Step 3: Laying Shingles
Now we are ready to start the preparation before tiling the roof with the shingles.
The first thing I always do is draw some horizontal lines on each face to hopefully minimise my normal inclination to line things up sloping downwards. These are arbitrarily the width of my ruler apart and are for reference and not the actual line the top of the shingles will follow.
If you think about how the shingles will lie on the roof, it is not completely flat to the roof face. At the top they touch but the bottom of the shingle sits on the top of the row below. At the bottom we do not have this happening so to keep things lovely and consistent I glue a thin sliver of wood at the bottom of each face. This will kick the bottom row of shingles out to approximately the same angle as all of the other ones above.
It is then a case of slowly building up the layers of shingles from the bottom. I tend to lay whole sets all the way around and then mark the side pieces before cutting off the excess on the band saw. Do not worry about getting them to exactly meet the next face or if the corner breaks off them because we will cover any mess up in the final stage.
For a quick fix, you use waterproof glue to attach the shingles to the roof and that might survive a year or 2 but I want to give them away and hot have to repair them so I've used matchsticks and glue to attach them.
Through trial and error on a piece of scrap wood I match up a tiny 1.5 mm drill with the match thickness so they sit snugly in the hole. Now starting at the bottom I place the shingle set in place, mark the edge is required and drill 2 holes through the shingle and the underlying witch's hat structure. A spot of glue is placed on the end of a broken matchstick and it is hammered into the hole.
Don't forget to pinch off the striking end of the match else you might just end up creating a good looking fire :-)
Step 4: Finishing the Roof
On a normal roof, you would have placed a barrier below the shingles to stop water ingress. Here I've opted to do it back to front and place lead sheet over the apex of the roof and where the different roof faces meet. I've also tried cutting copper pipe in half and screwing the half rounds over the edges. Or cut along the length of the pipe and flattened it. All techniques worked well but I preferred the lead.
So the roof intersections are simply covered with 40 mm wide lengths of lead, whilst the top cover is a circle, cut once from the edge to the centre and then folded into a cone. When the shape matches that of the roof top, the excess is cut off. The covering material is initially laid in place and then moulded to fit with a pin hammer. A close fit and bending over the edges keeps it in place.
Step 5: The Finished Article
Just the table base to build now.
This is simply 3 pieces of unplaned oak with batons screwed at right angles across them to keep them flat and square. The uprights are very simply an old door jam cut up into square section strips and the corners cut off to make an approximation of an octagon. Dowels go up into the roof to keep the uprights in place and screws attach them to the base.
I'm lucky enough to have lots of old wood lying around so cost to me to create these bird tables is $0 but if you are not in this same situation you can still achieve something similar. If you can only get softwood and think the shingles won't work, paint them and the water cannot get into the wood an make it swell up. And if you do not have the larger workshop tools such as the band saw, you can create a simpler pitched roof requiring a much smaller number of cuts to be made.
Have fun and stay safe . . .