I’m considering changing the front bulkhead location on my VCP fiberglass boat. It has a footpump installed on the bulkhead in question. Through some miscommuniction, the bulkhead was installed further forward that it was supposed to be at the factory.
I’d like to use that space for more dry storage in the front compartment and reduce the volume of my cockpit as well.
I have done a limited amount of fiberglass work on my boat and have been talked through (a few months ago now) the process of making a custom template using a couple layers of 3/4" MDF for the new curved edge bulkhead (currently flat) in it’s new location.
I’m asking for advice from folks who have cut out bulkheads and then custom made their own fiberglass bulkhead replacement. So here are some of my questions:
How did you make your template? What release agent did you use?
Did you make a flat bulkhead or did you make the template such that you curved the edges of the bulkhead to distribute forces?
Is a bulkhead with curved edges suitable to install a footpump on?
If you made a curved edge bulkhead, which direction did you orient the bulkhead in the boat? And, which direction should a curved edge bulkhead be oriented considering the stresses of using a footpump installed on it?
How did you construct the bulkhead? Which fiberglass cloth, how many layers at what orientations, which resin and why?
I’m not committed to this yet and I still may have a local highly qualified shop do the work, however, I’d like to learn as much about installing myself as I can as I’d prefer to do it myself.
A Couple Of Thoughts You stated that you wanted to move the bulkhead to get more volume in your fore hatch and to reduce the volume in your cockpit. If the primary goal is to reduce the volume in your cockpit you might consider just placing foam blocks in the cockpit aft of the bulkhead. Your pump can be mounted to cut outs in the mini cell foam, did this on my current boat.
Second, determine how your bulkhead is currently secured to the hull. If it is glassed I don’t beleive there is a release agent, you are looking at cutting, grinding, and sanding. If and adheasive was used then you need to determine what it was and go from there. As an example, 5200 is fairly common and heat will work.
Assuming you do get your old bulkhead out you could use that as a templete for a new bulkhead. Or, you could use it for the new bulkhead. Again if you glass the bulkhead in you can use strips of cloth formed in an L shape one side glassed to the bulkhead and the other to the hull. If you make a new bulkhead you might consider a piece of 1/4" plywood with a coat of resin all around.
More important goal for me… …is to create more dry storage space. I’ve got 7" of foam in there now as a footrest with a hole in the middle to access the pump.
Current bulkhead is glassed in. Release agent is for getting the built up fiberglass layers off the template/form/shape used to make the new bulkhead.
Cutting out the old bulkhead, sanding, and smoothing area with layer of resin should be the simple part.
Using a curved edged bulkhead preclues L-shaping the fiberglass tape. Should just need to use flat fiberlass tape and resin to bond new bulkhead to hull.
I’ve considered using a marine grade plywood as the ‘core’ of the bulkhead. This seems reasonable although I don’t know if this would work for a curved edge bulkhead. Probably just have to build up a number of layers of glass.
Polyester? Epoxy? First of all, you should make sure if your kayak is made of polyester or epoxy. The way I understand it, epoxy can be used on polyester but not vise versa. You could of course stay on the safe side and just use epoxy, but having a kayak that’s both polyester and epoxy might make future repairs unnecessary difficult.
Using a thin board of plywood might be a good idea, I’d say two layers each side should be enough.
Apart from that, you could take a look at my site to see how I glassed in ready-made bulkheads. Scroll down for “Kayak finishing”:
I have used footpumps in a couple of my wood kayaks and made a template out of cardboard. 1/4" plywood will be plenty strong with a layer of glass on both sides for added strength and water protection. I have found that a fillet of thickened epoxy to hold the bulkhead in place is much stronger than fiberglass tape. It’s not that much work if you have some fiberglass and epoxy.
consider what you have already been told, since you say you have already been walked thru this process.
you don’t need any wood core, glass is sufficent by itself.
make a template, then make mold (use building insulation foam sheet(pink will do) and cut, then shape the edge a little rounded to give the curved edge)
cover the form with wax paper, wet out your glass on a piece of cardboard (2 layers 6 or 8 oz should do)
transfer wetted glass to the form, cover with more wax paper…let stiffen.
While its still just a little pliable, trim excess glass with a new sharp exacto knife
Velley boats have in the past , always been made with Poly-ester resin
once the bulkhead is made. go look at a new valley boat and see their direction of orientation. this bulkhead is new this year so do whatever Valley did.
use 2 or 3 inch pieces of 2 or 3 inch glass tape, to put it in. wet out several pieces, then start
use liquid skin on your hands, it gives you a better feel for what you are doing than gloves.
not really sure why you would go to all this trouble for a few inches more room in a front hatch. especially since the front is not where you really want all that much weight…sometimes it’s easier to say that after all the work is done…enjoy anyway
There's no need to make an elaborate 3D template unless you want to radically curve the bulkhead. The problem I foresee with doing so is that it must be a perfect fit or the curved sections will not mate well to the hull. I would not go that route, but it's up to you. I would just use a flat panel and curve the glass that holds it in.
Since you're moving the bulkhead back to a wider part of the boat, you can re-use the stock bulkhead if you remove it carefully. You can make a curved connection between the bulkhead and hull using the glass that you bond it in with. That pretty much happens by default.
Here's what I suggest:
1- After removing the foot pump, carefully cut out the old bulkhead as close to the hull surface as possible. Once it's out, clean up the rough edges with sandpaper and lightly sand the surface you'll be glassing.
2- Mark the new bulkhead location on the inside of the hull. Clean the area throughly, first with water, then with a good solvent such as lacquer thinner. Lightly sand the area you'll be glassing.
3- Hot glue some small support blocks to the hull on the side that you won't be glassing. As for which side to glass, it really depends on which is easier to get to. I prefer to glass the front side (so the glass is under compression when you push on the bulkhead), but if you can't reach it or see well enough to do the job, glass it from the cockpit side.
4- Hot glue the bulkhead panel to the support blocks, centering it in the boat. The panel is now supported well enough to allow you to glass it in.
5- Using epoxy, apply fiberglass tape that's wide enough to provide 1.5" or more of contact with the bulkhead and hull. Do not try to do the entire bulkhead with one continuous piece of glass, as it will inevitably fall out. Glass either the deck or hull first, let it cure, then flip the boat over and glass the other section, overlapping the first section slightly.
6- Once the first layer is cured sufficiently to maintain its shape, apply three more layers of glass tape. That should be sufficient to do the job, but you can add more if you feel it's necessary.
7- Once the epoxy is fully cured, knock out the support blocks and clean off any glue residue with solvent. Reinstall the foot pump and you're done.
If you decide to fabricate a new bulkhead panel, it's a simple matter to lay up 6-8 layers of 6 ounce glass on a flat surface covered with a polyethylene sheet. Place another sheet of poly' over it, cover with a piece of plywood or other flat material, then add weight on top to compress the layup and help to squeeze out any excess epoxy. Once it's cured, the poly' will peel right off and you can cut the bulkhead to shape.
Project went well. I ended up doing the curved edge bulkhead idea using 3/4" MDF as a mold. A thick coat of Evercoat release agent allowed the finished bulkhead to come off the mold. The mold had to accomodate a couple of RDF’s which complicated the whole process, but I’m happy with the results and all appears bomber after using 10 complete layers of 6 oz. cloth and 5 more partial layers in a couple of different orientations–this approximates the thickness of the original Valley bulkhead. Six layers of 3" tape around to hold the bulkhead in place. Polyester resin throughout–I didn’t want to get into the ‘can’t use polyester over epoxy’ issue later on. Foot pump has been remounted, foam footrest trimmed and all is set to go with quite a bit more dry storage space in the forward compartment.