Bow Plate: mould / template?

[Tim Good]

I'm investigating the idea of a stainless bow plate that will sit about 10 inches about the waterline, extend about 2-3ft back and about 2-3 fit beneath the waterline.

A fabrication company said it is not problem and relatively cheap to produce if I have a template or cad drawing. The purposes of this is just as added piece of mind as we take our 43ft boat to high latitudes where charts are not so reliable.

Does anyone know how I might create such a mould or template?

 

[Searush]

I made one for my first boat in cardboard & sticky tape.

I got s/s from a skip at a metal bashers & cut & drilled it to the template shapes by hand & then took it back to the metal bashers who welded it up for me for a few quid in the tea club. It fitted a treat & was stronger than even the original (an early westerly design so it wasn't feeble to start with)

 

[pvb]

It would be easy enough to make a female mould in GRP, then cast a male template from it.

 

[Tim Good]

It would be easy enough to make a female mould in GRP, then cast a male template from it.

So in between the GRP you just have a layer of film or something to prevent it bonding to the actual boat? Then just slap on the Fibreglass?

 

[pvb]

Yes, that would work fine. You only need a thin layer of fibreglass, perhaps with some rough wooden formers added so that it accurately retains the shape of the hull when removed.

 

[prv]

Yes, that would work fine. You only need a thin layer of fibreglass, perhaps with some rough wooden formers added so that it accurately retains the shape of the hull when removed.

+1, except I would say the stiffening ribs are mandatory for this purpose. If I've understood it correctly, you're basically making a flat plate with a V-shaped fold in the middle, and fresh fibreglass probably won't accurately hold the angle of the V without support (ie, it will tend to open up a little, or at least you can't be sure that it hasn't). I would cut a pair of v-shapes out of hardboard, MDF, or whatever else is handy, and tab them onto the back of your female mould before removing it from the hull.

All that said, this method does sound rather longwinded just to make a template for some metalwork.

Pete

 

[Tim Good]

What about some sort of laser scanner? Something that you can pay someone to come out setup and in 5 mins have a 3d cad model of the bow down to the nearest nano meter. Does that exist?

 

[pvb]

All that said, this method does sound rather longwinded just to make a template for some metalwork.

Yes, but it needs to fit snugly if it's going to look anywhere near decent.