Boom!

Build a boom, they said. It would be easy, they said.

Well, that was about all it took for me to take on that little job. How long can it take?

Started it about in the first week of November, still about halfway through it. I can blame part of the time on the winter here. It has gotten dark and cold:

and the darkness makes it a bit difficult to get going in the morning. The cold makes it expensive to heat the shop, at over $5 per gallon of heating oil. I have a wood stove as well, but wood is getting very difficult to find here.

But here are some pics of the project:

Building the form on an old strongback I had from building a kayak:

Using sitka spruce for the stringers.

Then two layers of 3mm luan mahogany epoxied onto the sides:

And some shaping, then 1mm of carbon uni-directional epoxied onto corners, inside and out - and some 17 oz. biaxial fiberglass over the carbon on the outside corners:

Turn it over for getting carbon on inside corners:

Glue up the two top skins, but don't yet glue to boom body:

So that is up to date for today. I'm also cutting out the sheave cheeks from G-10 1/4" fiberglass sheet and getting ready to install them. First I will coat the inside of the boom with 6 oz. fiberglass cloth to give good weather and wear resistance. I'll need to figure out a way to do some blind coves with the carbon uni to join the top - still struggling with how to do that, as there isn't much working area. I'm thinking I will screw the cheeks in as a unit (2 sheaves per sheave box) by gluing them into a unit. The sheave pin will extend to outside each side of the boom, giving some strength. I may add a second pin just for some more strength to holding in the sheave box. There will be a pair of boxes at each end for reefing and outhaul. (total 8 sheaves). Pics when I have them.