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> I have heard other builders suggest that when you tape the hull to deck
> joint, you roll you tape onto a stick and soak it in a container of resin.
> This pre-soaks the tape.
> Other than a little extra resin waste and a little extra mess on the
> plastic throw sheet, why couldn't this be done with the hull and deck
> cloth?? It seems that from everyone's description the problem is caused
> during wet out of the glass and this would be eliminated with pre-soaking.
> There must be a problem with this idea as it seems too simple!!
> Ian
How fast can you work? Here is a math question for you: How fast does a big batch of resin set up? How long does it take to cover a hull with a layer of soggy glass cloth and roll or squeegee it into place? The difference between these two times is the amount of time you have to soak the material and roll it up before trying to apply it.
There is no guarantee that prewetting will keep air bubbles from being trapped. I can't see how they would escape from the soaked glass cloth while it was rolled. It seems there would be too many layers of cloth above to trap them in.
You would hve to pretrim the glass to the approximate shape needed, or you would have a lot of waste. Soaking a rectangular piece of fabric would waste both the excess glass cloth that is later trimmed off and the resin absorbed in it.
If you plan to try something like this you will need a suitable tray for soaking the roll of glass cloth. I suggest you use a piece of 3 inch or 4 inch PVC pipe. Get 2 endcaps. Glue them on the ends of a suitable length of this pipe and then cut the sealed tube in half with a saber saw. This will give you 2 round bottom trays. Mount them so they don't roll over while in use.
Lay your fabric on your boat and trim away the excess. Use a piece of 1 inch or 1 1/2 inch PVC as a core, and start at one end, rolling it toward the middle. Stop at the middle. Take a second piece of PVC and do the same thing, but start from the other end. When you are finished you will have two tubes with cloth wound around them. secure them together with rubber bands, and put a piece of masking tape on the boat to show where they came together. Put the tape on the side of the boat (inside or outside) that is NOT going to be covered with the glass cloth!
Take the rolled glass cloth to your round botom tray and pour resin over it, doing first one roll, and then the other. the center of the roll of fabric will be thickest, so concentrate your efforts there. When it is saturated well
notes: you may want to plug the ends of the PVC used as cores so that resin doesn't get inside while the fabric is soaking. If your cut cloth is going ot be, lets say 38 inches wide at the widest point then your PVC cores should be a few inches longer. The tray can be either long enough so that the entire core can fit in, allowing the glass to touch the bottom of the tube tray, OR, you can cut notches in the endcaps of the tube trays and let these support the PVC cores. If you do this, the ends of the cores will stay cleaner and you can use a slightly shorter tray and a slightly longer core. Mark the PVC cores so you can determine which one has the cloth for the front of the boat, and which one has the cloth cut for the back end of the boat.
When you go to apply the cloth, set the pair of PVC cores back at your alignment mark tape and roll out one a few feet, then unroll the other a few feet. Get an assistant to hold a cores and rolls while the unrolled glass is squeegeed to the boat. Once the center is in place you might as well go all the way to the end on one side. If there are any areas that are still dry you will want to get them wet fast. While you are working on that one end, the rolled material for the other end is hopefully not generating enough heat to set it off. Get back to the second end as soon as possible and unroll and attach rapidly.
I don't think I would want to do the inside of a boat this way, but the outside might be possible.
I would not want to add more resin to the fabric at this stage, as I think it would run, nor do I want the resin that is saoked into the fabric to be absorbed into the wood, so I would precoat the wood with a thin layer of resin and let that set up before applying the wet cloth.
If I had the scales, I'd weigh my empty PVC cores, then weigh them again when the fabric was wound on them. The difference would be the weight of the cloth. I'd mix up about half that weight in resin (rough estimate) for soaking the cloth. The addtional coats that fill the weave should eventually give me a good ratio of resin to glass.
I have not tried this, but this is my best guess on how to do it. Good luck to anyone who tries. It sounds very messy. Working with wet 36 inch wide glass cloth sounds 12 times messier than working with 3 inch wide tape.
Paul G. Jacobson
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Guillemot Kayak - High
Performance Wooden Sea Kayak Designs
