Quote:
|
Originally Posted by meerkat hi Mik
I read through your FAQs (might I say quite interesting and well put together) and I have a few questions.
Rather than using 2 pt polyurethane you recommened using epoxy with a poly topping (1) is this right ? The coats of epoxy are as thin as you can get them.
So i'm thinking....
the deck has 2-3 coats of epoxy with a coat of poly
inside has the 2-3 coats of poly (unless the epoxy is good there too). The problem with the inside is that there is some drips of epoxy that has been left there from a previous attempt to repair the deck as well as some black lines going across the boat and up the sides(why I dont know). so I'm not sure how that will come out.
The hull will be painted.
Oh yeah, after removing the lid there are a lot of holes left by screws, copper nails and yes even steel nails :mad: that have rusted & expanded and left holes like what screws do !
Whats the best to fill these with and will that affect the nails going back in ?
thanks
Andrew |
Hi Andrew,
You probably don't need to put any nails back in. See the FAQs I gave the links to previously about
Cordless drill and,
Eliminating fastenings.
As far as gluing you just need to hold things together while the epoxy sets up - no need for permanent nails or screws.
As far as drips etc on the inside remove them by sanding - random orbit sander is good here - about 100 grit paper - be VERY careful not to cut away at the plywood veneers!!!
____________________________________
Before committing yourself to lots of epoxy coating it may be worthwhile reading the rules about what is a and what isn't counted in the hullweight and then weighing the boat in that condition.
Also read whether lead (metal) correction weights are allowable and checking whether there are any fitted - remove them before weighing.
The decision tree goes a little like this.
If the boat is much more than 5kg over - it is a short term boat - it will be pretty well impossible to get it down to the minimum. Clean it up just as much as you need to get it on the water. Your son will race it for a year or so and then will start to have enough experience to make a better boat go well. Don't spend too much money on this type of boat.
If the boat is only a kilo or two over it is a good boat if it is ready to go in good sailing condition. Just patch up to keep going, you can't afford to add much weight in epoxy (or anything else) so just two very thin coats. Bote Cote have a product called TPRDA that thins epoxy out without destroying its capacity to protect the timber - use it to the max allowed - roll the epoxy out well spread. Adding thinners to epoxy is not cool for boat use.
If the boat is under weight by a kilo or more - you're in luck. Provided the hull is stiff and fair (the chines and panels have nice geometric shapes - nice even curves, no hollows and bumps) this is the sort of competitive boat that is worth fixing up and giving the full epoxy treatment to.
So weigh it and see what you've got.
____________________________
2 pot polyurethane is only really for finishing the decks off - it gives a very strong surface with a good appearance, you would need 3 coats minimum. As an alternative you can use a good spar varnish as an alternative or paint the decks with a marine enamel.
YOu wouldn't use any of the above inside the bouyancy tanks as their purpose is to give a good appearance..
If the boat is two or more kilos overweight an alternative for inside is to use Everdure - a couple of coats. It is nowhere near as effective in keeping water out of the wood as using epoxy, but it doesn't weigh as much.
Epoxy coating is good from a wood and weight preservation perspective, but it will add a couple of kilos to the hull weight - even if you are careful.
If the boat is going to end up being pretty competitive with that added weight (ie no more than a kilo over minimum) then epoxy is a worthwhile investment - depending on how much labour is involved. Or just add the epoxy as you do work on the boat.
___________________________
The most common pitfall is that someone in your position gets all excited about fixing the boat up. They lose track of the fact that the boat is probably pretty close to sailable now. I would suggest doing the minimum you can get away with until you find out how commited your son is.
Another thing is not to overcapitalise an old boat unless it can be competitive - ie close to minimum weight, fair and stiff. Don't add new sails, new masts to an old clunker. Maybe pick up some second hand sails from some of hte top sailors in the class if the ones you have are shot. Replace other things as necessary. Then see how enthusiastic your son is after the first season.
A cheaper and a better way to get a fast boat is to buy a good second hand racing boat that is doing well in its fleet than to completely re-outfit an older boat with new sails, mast, rigging and fittings.
So weigh the boat and inspect it so you know whether it is a goodie.
If it is a bit heavy or out of shape - just do the minimum to keep it going - after the season sell it for what your bought it for and get a current competitive boat.
____________________________
One labour intensive but very effective way to lift performance is to make some highly accurate and smooth foils - rudder and centreboard. They can then be moved onto a new boat when the time comes.
Shape is important so you have to use templates - contact me on
storerm@ozemail.com.au
if you are after templates and an instruction sheet.
______________________
Sorry this is a bit rambling - trying to cover a lot of ground
Cadet MK2 
.
