I'm at that point in my Henri IV build, where I need to fibreglass the bottom of the hull. Problem is, I'm not sure what weight of cloth to use. I don't want to go too heavy because its a small ship, but I don't want it to be too light (if that is possible ) either. If someone with wood hull experience could suggest what weight of cloth I should use on my Henri IV, I'd very much appreciate it.
A .5 to 1 ounce cloth will work fine. It is thin enough to drape and pull on curved hulls. I do suggest doubling some areas such as the bow and the stern for added protection against BBs. I usually buy mine from Tower Hobbies. I also recommend a quality resin such as West Systems. Yes, it is higher priced but you get what you pay for. I tried low cost resins from Lowes before and had to reglass two hulls because the stuff never cured as well as West System.
Thanks. I already have West System resin because it doesn't stink, since I hate the smell of the other kinds of resins used for fibreglassing.
I did my Maru's hull bottom with whatever weight of fiberglass cloth was at Lowes the day I went (I think 4oz?) and cheapo polyesther resin. I had no problems other than the horrid smell, 4oz cloth doesn't do curves so well though and tends to want to do in different directions than you want it to, so you would likely find it troublesome on a hull like Heni IV's. On the resin note, I'm using West Systems epoxy resin on my Moltke rebuild, primarily for the no-stink factor, and it is fantastic to work with if youre not in a hurry for a cure.
West Marine sells fiberglass MUCH cheaper than tower hobbies or any other place. I bought a 6 by 1 ft piece for about 8 bucks the other day when I also bought resin. I don't know the 'OZ' of it but its not a thick weave but not real thin. It was flexible enough to warp around the bulges and still give me the strength on the bottom of the hull that I needed. I had ground up the inside of the hull so much that it was paper thin in places. I may put a finish sheet over that with a super fine sheet to give it a smooth texture depending on weight. I wouldn't worry to much about the weight though.. I have been running my ship for a while with chisel punctures and a paper thin bottom with no problem. Personally I wouldn't overdo it unless you have the weight to play with. It just isn't that necessary.
If your fiberglass isn't curing, chances are that isn't getting hot enough. Put it in the oven at 200 degrees F for 30 minutes or so. Another approach was to put it in the beater car during a bright sunshine day. You can pick up cheap used ovens to put in the garage off craigs list after you get banned from the house...
I think the reason most people like West System, is because of the lack of smell, not how well it cures. Atleast thats my reason for using it.
I like the lack of smell, but it's good to handle in 3 hours with the fast-cure hardener. That's why I buy the gallon jugs with the pumps
I can't say I've ever noticed the lack of smell now that you mention it. I use west just because it is better and more consistent than any of the other epoxies I've used. My rookie boat had all sorts of issues with epoxy not bonding strongly to things and peeling off when they got wet. The west pumps are worth their weight in gold as I'm pretty sure that the whole squeezing out equal parts A & B is what caused some of my issues. It isnt cheap but it isnt really that expensive either, plus the results are worth it since I trust it to hold my boat together and waterproof alot of my electronics.
Once upon a time I built a Q500 pylon racer of my own design and took it to a race. The plane was built with the thinnest wood I thought was possible and still take the high Gs of racing. Unfortuantely, the V-tail was too thin and flexed. After the first day of racing, I went home, stripped the original tail off, and built a new one out of slightly thicker wood. The new tail was also fiberglassed. But the plane had to race the next morning and the resin wouldn't have been cured, much less ready to glue on the plane. So I fired up the oven and baked the tail for a couple hours at a couple hundred degrees. The tail came out fully cured (and hot) and ready to glue on the plane which I did that night. In the morning, the plane was good to go and flew well up until I crashed on takeoff during the final heat of the event. Heh. Baking does work. It does smell when baked, even using West Systems. Luckily, the wife let me live for doing it in the oven. lol.
West has _a_ smell, but not nearly as bad as most other epoxies, especially in quantity. I've glassed whole sections of a small (8') sailboat hull and the smell isn't bad. That said, I've never in my life baked epoxy to rush it. Wife would KILL me.
Our convection oven has a bread proofing option and will go as low as 100F, so that might be something to investigate too.
Did I mention that my wife would kill me? This would be worse than that time she caught me using epoxy over the living room rug with no dropcloth. I did buy a small toaster oven and an oven thermometer for hardening cast turrets in the shop. That worked reasonably well. (If you use Smooth-On products, they have heat-treating guidelines on their website. Not sure about heat treating other castables)
I'm almost at the point now of Fibreglassing too - without a clue on what I am doing! So, I'll just settle with the instructions on Mike's Bearn build. Thanks Mike
