A Few Layup Questions

A brief, middle of the night phone post:

My topsides are horizontal in the lowest part of the mold. I plan to start in the bilge. The bilge in this picture, is where I have started putting the longitudinal strips.

 

A brief, middle of the night phone post:

My topsides are horizontal in the lowest part of the mold. I plan to start in the bilge. The bilge in this picture, is where I have started putting the longitudinal strips.

 

I dont want to highjack your tread cat but maybe a layup question for both you and brian. My scantlings called for 1715 biax inside and 1715 and 1 1/2 oz mat out with added layups inside of keel and outside of keel. Your glass is 34oz cat about .050 thickness, Brians is two layer 18oz about the same thickness 17.3oz double bias app. .029. My mat adds no strength to my layup, so replaceing the mat with only one layer of 18oz bias should give me about the same layup as you and Brian. I will be under the rule of thumb chart for FRP thickness and aprox. wt./ft.sq for my size boat listed in ED Horstmans book. If you and Brian dont have added layups should I be concerned with puncture resistance, am I,m worrying about nothing? rick

 

Thanks, everyone. A few comments...

Brian: I'm striving for a good 50/50 glass/resin ratio. It's important to me in this hand layup because I chose to do a hand layup instead of bagging or infusion that is encouraged on my boat. I can't accept pools of resin dripping from the bilge (or deck) onto my topsides. I might be a little anal, but I am striving for the best quality boat I can build - this means I have to be disciplined. It's a performance cruising cat (See Cat Here) and I don't want to compromise anything about the design to slow it down or add weight, reducing my payload. So... I have to squeegee to be sure of resin content, as a beginner. I'd love to use War Whoop's method, but I'm not that good yet. He's a pro builder. I'm just starting out.

Brian again: The coat between the triax and the foam of cabosil thickened epoxy is to make sure there is enough epoxy between the two materials and that it doesn't go anywhere. Also, I believe it would help with any "waffling" that occurs between the heavy triax and the Core Cell. Delamination is my #1 concern/fear here, so I am just trying to do what works best... whatever that is.

Mark: I agree with you on not pre-pregging on a table in this case. Aside from exotherm issues and a bad clock ticking, it seems like in this case it'll be awkward to do for me. I also will give foam rollers a try without metal... but I'll try it all on some samples first to see how this 34oz (1150g) triax wets out and sticks to the foam. It is strange working down here, but it's way better and cheaper... I can work all year round and not spend $12K a year to heat a building. Summer is insane though. A couple months are unworkable during the day. You have to go to night shift.

 

Two more things about the rollers.
1.) I would at least try Whoop's power roller suggestion. I have not done this but you could have a pot and long hose and keep all of your resin in one place - much neater and less likelyhood of a spill. To clean up, have plenty of vinegar, then acetone the small amount you didn't get with the vinegar. A little acetone left in a brush, roller, etc. is acceptable in your next batch. Get one of these

keep it by a bucket of acetone (I use ammo cans) with your used brushes/rollers in it. Two or three scrapes of acetone out of the roller and you are rolling again. (remember that you cleaned the roller before you put it in the ammo can and that acetone will stay good for the entire project)
2.) If you practice a bit, you can get a feel for the rolling and suck any amount out between sloppy/wet and starved. You will be able to see where you are on this. Actually better than sqeeg, which tends to starve or leave a little ridge of resin at the edge. If you do sqeeg, there is long rubber squeeg available you can get from fiberglass supply house, cut to what length you want. I am not a big fan of the little yellow plastic ones - they always seem to have a burr to be found in the middle of a project. I use 'em for making radii and not much else. I would try not to work it too much from the outside - the resin can aeriate (froth). By all means, keep a squeeg handy and try a couple of diffent rollers to see what nap you like. What I use may not be what you like but they need to be solvent/epoxy compatible.

 

Check to all of that. I do love the 5-in-1 tool too. I used to use those when I was a college kid painting on breaks and in the summer. I always have one in my tools.

I didn't bring enough ammo with me to need an ammo can here in FL, but I'll find something that works.

Thanks.

 

I was on multihull4us and saw a post about 50' kurt hughs hulls for sale 25'000.00 cat thought I,d let you know. rick

 

Yup. There are quite a few of them out there that are half finished in wood/epoxy.

Of course, the builders invariably leave them out in the sun and rain, unpainted and unprotected for 5 or 10 years before they decide to sell.

I've looked into every single Kurt Hughes project boat out there. If someone reading is considering one, just remember these two things:

1) Rain soaks into unprotected wood.
2) Unpainted epoxy degrades quickly in the sun.

Run from these boats, don't walk.

BTW: There is one of interest in Long Island, NY. It's, I think, a 50 footer's hulls, but they're an ugly old design with a "knuckle" above the waterline. However, this project appears to possibly be in good shape. I haven't personally looked at it, but it does appear to be worth a look to someone who isn't interested in building hulls. I think this is the one from multihulls4us.

 

No there is no problem but I can not see any advantage only disadvantage.

 

Hmmm... those are some good points.

For #1, I was planning on heat-bending my foam to meet the curve of the bilge and screwing it down. I didn't think I needed to do any strip planking at all looking at the Farrier builds online. They all seem to bend the foam right around like a pretzel, even on the topsides/deck radius, which is super tight.

For #2, I am a little lucky and a little unlucky at the same time. I got Core Cell on sale because it's small panels. They are just a bit shorter than 50" (44"??) so I figured I'd stop at the edge of the foam for the first part of the layup. That should eliminate any over-runs of epoxy onto virgin foam. It will just drip on the floor.

#3 will need some serious thought.... not sure how that will go. I suppose if I get to that point and find that it is indeed too slippery, I can resort to trying to reach in from a platform outside the mold to do the deck lamination. I sure hope I don't have to, but I guess the option is always there, right?

So what do you think? Do I have these covered?

 

I forgot that you got the small sheets at the bargain price.
You will not have problems standing in the hull to do the deck laminate as the topside will be horizontal there. But I think you will have a problem doing the topside laminate if you want to stand on the lower topside section.

My experience with thermoforming is that using heat guns is only good enough to do only very small pieces. Otherwise you need a very good high kW fan forced thermostatically controlled oven. When heating the foam you need to make sure you dont overheat it as it will reactivate (start to expand) which leads to reducing the foam properties as well as inconsistent thickness in your planks.
Dont recall which grade of corcell you got, but corecell A reactivates at ~75'C.

 

There will be some experimenting to do. I am certain of it. I have 1" foam and I was going to try the heat bending. If it doesn't work, I will go back to the longitudinal pieces in the curves. As noted above, I should be able to still do the longitudinal pieces if I have to because of the order in which I'm putting in battens and doing the lay ups. I'll try the Farrier way for bending the foam. If it doesn't work, I'll do longitudinal. I'll do a lot of experimenting at first.

Either way, thanks again for all your help. I am looking forward to all of this horizontal glassing. Should be much better than vertical. Also, the bridgedeck line as a batten was a great idea.

 

You can soften the plastic (Thermoplastic)with excessive heat and the gas (nitrogen) bubbles expand,There is no chemical reaction.

 

CatBuilder, I did assume you will be leaving the not required battens out to assist the access for the staged glassing jobs, so this does not change my reasoning.
I guess I do not see the advantage of starting in the bilge that you do, what is your reasoning?

I would not recommend that you stop the topside laminate +/- 0.3m of the deck radius.
The reason is that you are using full length pieces of glass, much easier to unroll and position the glass cloth when its all either on a vertical or horizontal plane, not something that goes through a 90 deg bend.
This is another advantage for starting at the sheer line.

 

Thanks, Mr Whoop. Good to know from a guy who has used more Core Cell then anyone.

Andrew: My reasoning is that if I do it the way I'm describing, I can reach everything. If I don't, I will not be able to physically reach the bilge curve with my hands, only with tools on the end of extensions. So... I figured being a beginner, it is much more likely I will have a successful layup if I can physically touch everything and it is all at about the height of the counter in a galley.

I can really get in there and press, slide, squeegee, whatever... I will be able to touch everything with my hands to help with positioning, wrinkles, excess resin, etc...

That's the reasoning.

I am understanding your last statement, but I am not understanding how to handle the hull/deck radius if I don't stop somewhere near it. So are you saying that you stopped at the sheer line on the topsides, then started again up on the deck and didn't squash your laminate into the hull/deck radius? Did you tape in there?

I had planned to bend part of one of the layups (either topsides or deck layup) over just a bit to cover that radius. I figured maybe the bottom (topsides), horizontal layup might be easiest to press in there, then I would use another run of triax down the entire deck on a different layup.

No good?