I purchased some Hoop Pine to make a mast over two years ago now, and finally set about the job recently. Last year I bought plans for the GIS and have used it's birdsmouth mast construction to build the mast (see attached). My inital problem was that the Hoop I had bought was 4.3m long and I needed 5m pieces. I scarfed the additional lengths on and then when cutting the staves to shape ( Yes Mick I tapered them ) I set the scarves 4 up and 4 down on alternate staves. I expect this wont present a strength problem as each piece is well supported according to the birdsmouth construction.

I cut the V grooves, using a horizontal boring machine (Shopsmith) doing progressively deeper passes with a 45 degree router bit. Then marked out and cut the tapers. Weilding thin 5m pieces of timber is not easy and I came up with this process as it allowed me to do it by myself.

I then waited some considerable time for she who must be obeyed to go to NZ a holiday so I could do the next part, mast assembly. You may be able to tell from the pictures, this was not done in the approved working area.

Micks plans call for the mast to be made so that it will come in half. At this point it is crucial that the assemblers dry run, more than once, the assembly sequence. You have no time to mess around when it is coated up with epoxy. Also make yourself an octagonal former to fit in the base ( Large end of the mast ). Remember to put a screw in it so you can extract it before the epoxy sets. This makes it easier to assemble without playing pick up sticks.

Clamping the Staves together flat on the floor (so minimal epoxy could get to the sides) and Using West Resin (206 Slow Hardener) we coated the V grooves with 10 mins between coats, hopefully this aided absorption. Still with 206 Slow Hardener I then made up a batch of epoxy with micro fibres and applied liberally. Do not be economical here. A dry joint will be difficult to remedy.

We followed our pre-planned assembly programme, securing with cable ties and viola. I attach pics of the assembled unit. Using cable ties it is difficult to apply the pressure required to squeeze a joint dry, so this is a good thing.

Two things I would do differently. Firstly, Enlist help and use a Table Saw to cut the V Groove. Secondly, put more paper down, I fear I may cop grief over a minor spillage.

I post some pics of the finished unit (probably another 2 years )