: Having not mastered the art of the short post,

Boy...I'll say!

here is a summary of these
: questions: 1. Is 5.2mm lauan too heavy to use for an 18' boat?

This is a loaded question. Luan is not one of the more desirable plywoods used to build boats. First...it can have voids on the inside plies. Luan can also be heavier than a corresponding thickness of marine plywood...but not always. Many, many boats have been built with luan. I've built many boats with luan. You can check luan carefully to get the best sheets you can...but you are still probably going to get voids in the inner plies. As for your question about whether that thickness is too heavy. How heavy do you want your boat? It will be heavier...perhaps 5 pounds...perhaps 10 pounds. How light should your boat be? It should be as light as you can make it and still have a good degree of safety built in. Why?...mostly because a heavy boat is hard to carry around and launch. Once it's in the water...you won't see a whole lot of difference. Some...but not much.

: 2. What weight cloth can I get away with if doing both sides hull and deck
: with 9oz taped interior seams and reinforcement strips.

Another loaded question. Using basically 1/4" luan you COULD get by with no cloth inside and out as long as you tape the seams and encapsulate with epoxy. 9 oz. cloth is pretty thick. You really don't need it that thick. 6 oz. would work fine. Once scenario is to tape the inside seams and cover the outside with 6 oz. e-glass. You could even use 4 oz. cloth, but the weight savings is minimal. I would also tape the outside seams simply for added protection, but it's not necessary.

: 3. Do Raka's epoxy pumps work well?

I don't like pumps because they burp. If I use a pump...I'd still pump into a graduated mixing cup to make sure of the mixture.

: 4. Will the thick and presumably soft core ply of the lauan dictate thicker
: cloth for puncture and ding resistance? Will it make a weak composite
: sandwich?

Should I say another loaded question? Not really. There are just a lot of different solutions for different problems. I would say no. The composite of epoxy, e-glass, luan core will be quite durable. A hidden void can be a problem, but probably won't. If you ever damage your boat...it's easy to fix. Heck...you built it. I'm certainly not saying the luan will be as good as marine plywood, but it will make a quite servicable boat. Regardless...I would still recommend that you purchase marine plywood if you can. If you are simply experimenting, or trying to gain experience before building your dream boat then the luan will be fine. Like I said...I have some luan boats (and boats built from 1/8" paneling...but that's another story).

: 5. Where do you get copper wire for stitching locally? Or online.

Frankly...I don't use copper wire and see no reason to do so. I guess if you leave the wires in it might be ok...but I don't do that. I go to Walmart, or Home Depot, and buy fine tie wire. I stitch the boat, fillet between the stitches, then remove all tie wire.

: Went down to Home Depot today and bought some 5.2mm lauan 4x8 panels. They
: had 3mm also, but this was in 3x7 panels, and looked crappy with voids.
: Thick stuff has no voids visible with light (but they may be discovered in
: cutting), thick core, really thin outer veneers light and "OK"
: looking on one side, dark and rougher on the other. It feels pretty heavy,

The luan will usually be a little heavier...and stiffer, harder to bend. Sometimes it'll break or split. Something you just have to be aware of. If you get to pick through the pile of sheets sometimes you can find lighter sheets. These light sheets also bend better.

: but I've never held a full 4x8 of 4mm Okoume before so I can't judge. Ross
: Liedy recorded using 5mm lauan on his version of the Sea Kayaker S&G. He
: also commented that perhaps battleship gray paint was appropriate but I
: got the idea somehow that his boat came out around 50#, which I would
: consider acceptable--but I think I gleaned that from one photo caption
: which said 45# for the hull and deck and it wasn't finished.
: Ross, you around? How much did your boat weigh?

50 pounds for an 18' boat built with luan is about what you can expect. If you are new at this building it may be heavier....not because of the luan, but because of the added epoxy, goopie, etc.

: If you don't think it's too heavy, what about in terms of bending? I *think*
: that if I build the boat with the paneled deck as designed, it should make
: those bends. Maybe some trouble with the bow and stern joins. But will I
: wind up with a 65# + boat?

You might end up with a 65# boat. Partly because of the luan...partly due to how you build it. The luan will make the bend...but, as I mentioned earlier....you might have trouble with a bad spot breaking or cracking. If this happens you chunk the sheet and use another. This is just one more reason to use marine plywood for most boats.

The four full sheets of wood are too cumbersome
: to hold at once, but just lifting the edge on four sheets is heavy. I'm
: not worried about it being a little bit troublesome to fit and stitch, if
: it works in the end, my primary concern is that it may just be too heavy.

: If it is deemed usable then what does the collective say about maybe using
: all 4oz FG cloth instead of 6oz on the hull and deck with 4oz inside? I
: don't have a good feel for weights of cloth.

4 oz. cloth would work fine, but I don't see that you will gain anything on this boat. When you gain experience and start doing different designs with better materials...then you might want to use 4 oz. cloth. 6 oz. cloth is basically a standard.

The stuff in my previous kit
: was heavier for the hull than the deck. I *think* that was 4 and 6 ounce.
: Also, what about the structure of the composite sandwich? Aren't thicker
: softer cores more susceptible to puncture or dents and dings possibly
: compromising the skin?

I've never seen this to be a problem. Scratches and little dings are the biggest problem. Actual punctures and structural damage is something else. I just happen to do marathon paddling on rivers, etc. where we hit rocks, stumps, logs, and other objects (sometime another boat).

Should that be offset with heavier glass?

Actually...I did this by adding multiple layers of cloth. This was a mistake. Learning how to paddle the rivers and rapids was what I had to do. Another thing is additives, and/or other stuff to make the fill coats more scratch resistant. HOWEVER...this is not really something you need to worry about unless you are planning to jump logs or drag your boat over rocks.

How much
: weight does a glass job add anyway, roughly speaking?

I'm not sure. 5 pounds at a guess...but don't quote me.

Is two layers of
: lighter cloth stronger than one layer of thicker?

Usually but not always. I think it's better to use one layer when you can...but sometimes two does add just what you need.

My understanding is that
: most of the weight addition in glassing comes from epoxy. What do the
: ounce designations on the cloth mean? Is it 4oz a yard? Or 4 oz per sq.
: ft?

Per square yard.

: I'm planning to go to Raka for epoxy and cloth as many folks seem to be
: pleased with them and I have not found any cheaper prices. Speaking of
: which, do Raka's pumps work well or should I maybe think about using
: syringes and measuring cups?

Well...everybody has their own opinion about epoxy. I've used Raka. It's fine. I use USComposites now. It's fine.

: One more question: Where in the heck do you buy copper wire or other wire
: suitable for all this foolishness?

: Thanks!
: TD

Ok...just remember all this advice is worth just what you paid for it. have fun.