As an amateur boat builder, the process of building a moth starts with the preparation of a workshop from which the rest of the project will either succeed or fail.
Having visited Mike’s factory, I became aware that a clean, well laid out workspace is pivotal to a successful build process.
The first thing I had to do was to insulate the roof of the garage as the temperature was so cold in there that the resin would be unworkable. 18C is the best ambient temperature to work in and thanks to the cellotex, I can achieve that now.
With regards to heater choice, I opted for two 800watt Quartz/ Halogen heaters. For the cellotex oven, I am using two tube space heaters. This is all based on advice from Mike who has been through the whole process so many times.
Materials list is as follows:
10m 200g biaxial carbon
10m 200g twill weave carbon
1 sheet – corcell 5mm (for use in the deck, prodder)
1 sheet – corecell 3mm (hull walls)
3 sheets – c-mat/ contour foam (bottom of the hull to cope with the rounded section
12kg – Sicomin 5550 resin
5kg – fast hardener (parts/ glue)
5kg – slow hardener (hull)
300g colloidal silica (glue)
300g microfibres (glue)
Vacuum bagging materials
With the workspace in check, it was time to start the actual build with laying up the bulkheads and prodder. The idea behind doing these smaller layups is to get a feel for the resin and how it is working.
Rule number one for an amateur builder… this is not a one person affair. If you attempt to do this single handedly, it will end in tears! The optimum team is three. Any more and the workshop gets crowded, any less, and it’s not as efficient.
I’m extremely fortunate to have two spanish students offering to help out. Javio and Jordi are both studying marine engineering at Southampton and are keen to get the experience as they are planning to build their own moths later this year.
Jordi started proceedings by laying up the bulkheads. It turns out that he has a workshop pretty much the same as mine but situated in a nice warm and toasty part of spain.
Next up was cutting out all of the carbon cloth, foam templates and vacuum bagging material in preparation for the hull layup. With Javio and Jordi, it makes things a lot less stressful and easier to manage. The plan is to build the hull this friday.
After that, the real work begins with the assembly of all of the components.
I am sorry Phil but you are the one who is a true Mothie, not me. All I did was put my hand in my pocket and a Moth magically appeared from China. What you are attempting here is something I could never do. I have neither your skill or your patience to attempt such a project. I wish you the best of luck with it and I will follow your progress with interest.
On the contrary Graham, I think being a mothie is about spirit and passion as opposed to any particular skill. I chose to build the boat now as there is no way I’d be out sailing in this cold weather! Mind you, if I had a boat…..?
Hi Phillipe, that looks way complicated! My new Mach 2 has just arrived to keep the Bladeriders company! Give my regards to the Spanish students, good to see Javi still keen after his first time out in the Mar Menor. I hope to see their boats this year in the somewhat warmer south…hope you are coming to Moth Fest! Send Jonnie my regards! Alan, Pro-vela, Spain.
Hi Phillipe,
Sounds like a great project, good luck.
Try to use as little of the Contour Scrim foam as you can, preferably none. It is nice and simple product to use, but also sucks up a lot of resin/core bonding material. With the curvature in the bottom of a moth hull, the 3mm corecell should suck down easily under vacuum. If you get any particularly tricky areas, just thermoform the foam with a hot air gun to get it to the approximate shape, the vacuum will do the rest.
If you do use the CS foam, make sure you flip it upside down over a drum/barrel, to open up the grooves, the fill these with a resin/microspheres mix, so that when the thing is placed into the hull you guarantee there are no voids which will be little Venitian canals for water to travel in later on…
The other problem, is that the resulting resin/glue/microsphere grid that you end up with means that if you do impact the hull, these regular hard spots will cause fracturing, so the damage from a small impact (e.g. heel of your foot) will be much greater then just plain corecell which has some give/bounce.
For bagging your foam on, try and get something a little lighter than the microfibres or colloidal silica, something like microsphres with a little bit of colloidal silica will be better. Some of the 12’s back home used microlite (fairing powder), but, i reckon that is going a little too far, you want a good core/skin join.
Have fun, wish I had a little vaccum pump, would be very handy!
Rob
The bottom of a Ninja is very hard to make with sheet foam. Lots of rocker and lots of curvature…