DIY bulkhead?

[bumblefish]

I have a 15' open dayboat with a small foredeck. I would like to build a bulkhead with at least one hatch to 'enclose' the volume under said deck. What is this best way of doing this. I had thought of a glassed in marine ply wall with a sliding hatch cover. I would appreciate any suggestions, well nearly any, and some guidance as to any appropriate texts to support this work.

 

[snowleopard]

boat details?

is the boat grp? if so i'd avoid glassing in a ply panel as a ply-polyester bond is unreliable. if you want to use ply, stick it in with epoxy.
it's easy to make up a grp panel: use a piece of melamine-faced chipboard as a mould (contiboard or old kitchen worktop), give it a couple of coats of wax polish then lay up a few layers of glass fibre with perhaps a couple of d-shaped stiffeners made by glassing over some plastic pipe. resultant panel can be stuck in with glass tape (sand bonding surfaces well first).
Better still is to use a foam sandwich but that's a little more specialised.

 

[bumblefish]

Re: boat details?

I f I use a foam core can I make a rough shape and then cut to fit? Finally securing with epoxy/fibre?

 

[tr7v8]

The standard technique when fitting out is a loose fitting 12-18mm ply panel, with taped joints overlapping onto the ply and the GRP. Use rough Grit paper in a grinder or drill on the areas where the ply and grp will be glassed over to give a good key.
The panel should be a loose fit as if it's tight then youl'll get "hard spots" in the hull and potential stress cracing.
Epoxy to polyester makes a poor joint, so as the boat is almost certainly polyester the use that for the overlaps.
Contact Glassplies in Lancashire (I think) for their brouchure and leaflets as it ontains mre than you ever wanted to know about GRP, their prices and delivery are very good as well.


Jim
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[richardandtracy]

Re: boat details?

That'd probably be the quickest & easiest method of all getting the right shape.

Regards

Richard

 

[Twister_Ken]

Drain plug

Slightly off topic, such arrangements are common on sailing dinghies like the Wanderer. As well as access hatches, it's common to find a drain plug fitted at the lowest point in the bulkhead so that any water that gets into the locker (condensation, leaks, wet gear, etc) can be allowed to drain out to somewhere where it's easy to bail or mop up. There are small proprietary fittings from companies like Holt-Allen which you could fit easily to your bulkhead in the construction stage. See http://www.holtallen.com/bungs.asp

Sorry if this a teaching-to-suck-eggs situation.

 

[castaway]

I see plenty of suggestions as to fixing your bulkhead. Just a thought as to how to get the corrct shape to make your first bulkhead template.. I think it is called a 'tick stick' and I've used it alot.

1.Fix a vertical panel approx 12in wide in the middle of where yr bulkhead is going to sit.
2.Find a batten that is a bit longer that half the width of the propsed bulk head.
3.Rest the batten against the panel and move it across the hull until it touches the hull side.
4.Draw a line along top edge of the batten on the fixed panel and also mark a refence point on the panel and also the batten and give that point a reference letter.
5.Keep on around the hull until you have a mass of lines and reference letters.
6.Remove the panel, lay it on the material you intend to use for yr template, and you will be able to transfer the data collected by reversing the process with suprising accuracy.

Hope that makes sense, Ive used it loads of times and it works very well.

Regds Nick

<A target="_blank" HREF=http://www.yachtsite.co.uk/fairweather>http://www.yachtsite.co.uk/fairweather</A>

 

[Strathglass]

There are various ways of adding bulkheads, and getting them to fit.

One of my favourite ways when I want a precice fit is to cut up several 1" wide strips of thin (2-4 mm) ply. Then use this and a hot glue gun to manufacture a template of crossed laticed strips glued together in position. This only takes about ten minutes and when you remove it you know if it will come out in one piece, and used as a pattern to make the new bulkhead. This is much easier than trying to cut something inside the boat.

When I fit a ply bulkhead I always put a self adhesive foam draft excluder strip right round the edge of the bulkhead. This minimises hard spots.
I prefer to use epoxy resin and fibreglass tape on both sides to stick a wooden bulkhead to an old polyester hull. It is very difficult to bond to fully cured polyester with polyester resin, epoxy is more reliable.

I must admit however that I am tending to use moisture cured waterproof polyurethene glue for many applications those days.

Iain

<P ID="edit"><FONT SIZE=-1>Edited by iainsimpson on 08/01/2003 20:52 (server time).</FONT></P>

 

[snowleopard]

sure...

make the foam a bit over-size and trim, it's hard to get a good bond right to the edge. vital to use correct foam: airex, herex or divinycel are pvc and closed cell, cheaper polyurethane foam absorbs moisture and breaks down easily.