Category: Build Progress

Today, we set out to build the enormous template that will hold all the pieces that makes up a rafter element. The longest rafter we have to manufacture is 6.1metres long! So we took 2 sheet of our regular 12mm thick plywood and cut 3 strips of each being 476mm wide. Then we chopped up 12 CLS timber pieces each measuring 590mm long to provide the footings under the plywood and also joiners to connect the 3 strips together. Then, we again chopped up some further 26 pieces of CLS timber but this time being 100mm long. These had a 6mm hole drilled down through the wider direction and with a 100mm long screws, were fixed down on the edges of the plywood at the same position of the footings. These smaller items provides constraint to brace and hold the flanges in place when we assemble the each rafter in turn.
There was a special requirement to cater for, for the LVL diagonal rafters and ridge beams, where all 17 of this type, comes in a variety of sizes, but most importantly, about 5 different heights. This means that we had to have some means of extending the width of the template and we did this by cutting a further 9 strips of the plywood, a set of 23mm wide, a set of 33mm and finally a set of 76mm wide strips which we can place alongside the main plywood base board and extend the overall width by a combination of different width by using one or two strips together and screw the second constraints in place to lock the whole lot tight.

It only just fitted on the floor of our workshop, the total length of our template is 6.6metres long! Phew!
We stopped slightly early to go back to the computer to make a definite and final list of the LVL rafters and ridges along with their sizes and how many plywood webbing strips we would need to build each rafter.
Tomorrow, we will slice up some more plywood sheets to make a stock pile of prepared webbing and also the same for the polystyrene foam strips too.

Today, we carried on creating more measuring templates, this time, the 40 degrees and 45 degrees versions. The 40 degrees one is a pair as there are a small number of rafters that connects up to the steel I-Beams (on the short ends of the Skylight).

The 45 degrees version is only needed for the wall end as all rafters goes up to hip and valley rafters instead.


This concludes the collection of the measuring templates, a total 6 in all. The other angle of roof we got, the 60 degrees over the front porch, is just an ordinary straight forward CLS timber and we can measure the required lengths in situ at the time.
The rest of the day was doing necessary adjustments to the construction drawings to reflect the real world and the sizes of our newly arrived LVL timber which is bigger than the original drawing was done for. They are 108mm wide instead of 100mm, and also we decided to make life a little simpler and not have fancy crafted double slopes and valleys in the top and bottom edges of the LVL and just leave them flat. This means adjusting the overall height hence why we have sat down at the computer and did the work of updating the drawings.

Today, we set out to create several templates to help us measure the distance between the I-Beams up on the top of the roof and down to the walls. Every rafter will be an unique length especially when going down along the diagonal hip or valley rafters.
we started with the 32 degree version and made one for the wall and two for the I-Beam end.

We needed two because the steel I-Beams we got are of two different widths so the template needed to hook up and bridge around the steel flange to land flat upright against the Kerb.

Then, to finish off the day, we created a Nibbed Scarf joint maker. This is a very long shallow diagonal cut across the timber with little notch ends. The traditional wisdom is to have at least a 5 to 1 ratio of the length being five times longer than the width of the piece of timber being joined together. We made a jig to help us guide the circular saw to cut across the end of the 89mm CLS timber pieces.

We tested this out and have glued and screwed together a couple of short pieces of the CLS timber and we will give it a week to dry and cure properly before we try bending the joint against a fresh CLS timber and see what sort of deflection we will get or indeed how much weight before breaking completely!!
Tomorrow, we will continue and make the 40 degrees version of the measuring tool and then carry on with other templates and jig as needed.

Today, we resumed our creation efforts of a Birds Mouth and End of Eve template. We had a think overnight and we have decided that we could use the battery circular saw machine after all. After careful considerations, we started building up the layers of the template and then lines of 63 CLS timber, three lines at the bottom and a gap for the 89mm CLS Rafter Flange and another three lines of 63mm CLS timber. All this was glued and screwed together because we couldn’t rely on the screws surviving when we cut a whole series of clearance slots at the different angles we will need for making the Birds Mouth. We have five angles in total as follows:
• 32degrees – rafters coming down onto Wall A and E plus M and I.
• 33 degrees – Rafters to Wall B and D plus L and J.
• 40degrees – Rafters to Wall P, N and H.
• 45degrees – Rafters to Wall O and K.
• 60degrees – Special Rafters for Porch on Wall C.
We printed off on A3 paper all the Birds Mouth shapes and stuck it down on our wooden template and drew lines across the surface and used our heavy duty mains powered circular saw which has a thick strong saw blade in it and sliced clearance channels along 8 separate slots. We then did the same at the other end of the template to provide a place where the Ends of the Eve is also done at the same time as both the Birds Mouth and where exactly to cut the end is very much related to what roof angle we are dealing with. The important factor is that the gutter’s must all line up to the same height, no matter what angle the roof is. So we had a collection of numbers to position where the jig needed to go for doing the end of the eves. Again, the heavy duty saw came into its own in making more slots so our battery saw can just slide along the guide and just cut the 89mm CLS timber where we needed and get the job done quickly.
Next, we took a square piece of plywood and cut out a right angle segment (plus an extra piece to accommodate for the battery saw base plate) and this will provide the actual and exact guide for running the battery saw long. This was similarly done for the other end to provide a guide for the different angles at the end of the timber which will in turn be connected to the Facia board.

We were successful at the end of the day, by creating a Birds Mouth notch and the correct angled cut on the end of the timber as seen below in the picture

It is quite complex but we made it or at least we hope, so as we haven’t used it in anger under full production runs so we will have to keep our fingers crossed!
Tomorrow, we continue with the next tools and jig template like the measuring template to help us get the length of each rafter accurate and be able to trim little amounts off the top end.