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JEM Watercraft technique questions.

Posted: Sat Oct 06, 2007 4:41 pm
by FlaMike
I'm not sure if I've been "cleared" to post under my user-name yet, or not. Just in case, I'll be posting under the same name I use on Old Sparkey's Forum, "FlaMike."

I'm looking forward towards building an up-coming design of Matt's. From reading a large number of post on this Forum, I see that the building method is a bit different from the Pirogue I recently built, designed by Uncle John.

I've downloaded and looked at Matt's free plans as he suggested, to start learning his building method. From what I gather, the instructions that come with his other plans contain quite a bit more detail than the free plans, so some of what I'm curious about may well be covered in them.

Not being known for my patience, I thought I'd get a jump on things and start asking questions now.

First off, I see where many are using plastic wire ties for the "stitching." An older method of this type of construction, and one I've seen some use here, was to use wire instead of the plastic. Now, I'm looking to get the best finish I can on this build and intend to go with a clear finish on the wood. It seems to me that using wire instead of plastic ties would let me drill smaller holes in the panels and those smaller holes would be less noticeable when filled.

Am I off-base on thinking that? If the wire would be a little better, then what size/type wire should I be looking for?

Again, I think my next question might be answered in the plans set, but like I said. . .

Before "tack-welding" the seams and then filling them in with the epoxy/wood flour mix, shouldn't the panel edges be "primed' with epoxy, without any additives? Kind of like a saturation coat that I'd normally apply to any wood surfaces that were about to be glued together, or have fg cloth applied?

In fact, I was thinking that I might want to apply a light, saturation coat to both sides and the edges, of all the panels once they've been shaped and ready to go, and a surface-sanding has been done, prior to the stitching. I don't think that would stiffen them up too much to work with, but if that's been tried and found to be a problem, I'd certainly like to know about it.

I think I have about 4,000 other questions to ask, but I'll hold off a bit on the rest. I just wanted to get ahead of the game before actually starting a build, and let the people on this Forum have a preview off what I'm going to be like when I do get my hands on the plans and start building. :D

Yep! Patience is a virtue,
it just not one of mine! :lol:

Mike S. (aka: FlaMike)
Spring Hill, FL

Posted: Sat Oct 06, 2007 5:20 pm
by jem
copper wire for stitches: smaller holes can be used with this method.

You can also prime the edges of the plywood before tack welding. Be mindful of possible amine blush issues.

Posted: Sat Oct 06, 2007 6:11 pm
by hairymick
G'day Mike,

Welcome aboard mate. I think you will like it here too.

I use .9mm galvanized tie wire. it is stronger than copper and the wire is taken out before filleting so it doesn't need to be corrosian resistant. It is also a lot cheaper.

Will reply more fully tonight. Did you get the free Laker plans? Great boat and way to good to be free IMHO

Posted: Sat Oct 06, 2007 9:20 pm
by FlaMike
Thanks for the replies! :D

I did get the free plans, both the Laker and the canoe, but as of now, I don't intend to build either of them. They were downloaded to study the build method.

Now somewhere around here, I've got a book that will translate that wire size from mm to gauge size. At least that's the way I usually see it sold. . . (Sounds like baling wire.)

If all goes to plan, I should be placing my Raka order on Monday, a 3 gallon epoxy kit and some 4 oz cloth to go with the 6 oz. I already have. Wood flour I already have, as well as a roll of fg tape that I doubt I'll need, since I'll be using fg cloth inside & out.

The one thing I'm going to have to track down is a source for 4 mm marine ply within driving distance. I've not seen Okoume around here, or Luan (Meranti) either, for that matter. Won't buy the ply until I find out if I'll need 3 or 4 sheets though.

I should have enough scrap pieces left over from the last build for all the incidentals, I think there's enough exterior grade 1/4" ply for the frames/formers/molds, if they aren't to be left in place. Wonder if that might impact the number of sheets needed? I mean if those pieces didn't need to be cut from the 4mm expensive stuff.

Hmmmm. . . It occurs to me I'm going to have to actually finish cleaning out from the last build. Guess that will keep me busy in the mean time. :D

Mike S.
Spring Hill, FL

Posted: Sat Oct 06, 2007 11:44 pm
by Kayak Jack
Mike,

On the four S&G boats that I built, I used plain, old stove pipe wire. Yes, it was used to hang the stove pipes running from the old, wood or coal stoves to the chimney. Hardware stores sell it by the roll. I don't know if it's cheaper than galvanized or not, but think that it would be. It is a black wire, and soft.

I cut it into 3" lengths, then bend it over the edge of a piece of 3/8" plywood so it looks like a large staple. I found that if I don't bend it symmetrically, but with one end about 1/4" longer than the other, it was easier for me to insert it into the holes and thread it all the way through. I'm one of those fellas with 13 thumbs.

Posted: Sun Oct 07, 2007 5:03 am
by hairymick
Mike .9mm is a little smaller than 1/16".

I use a 1/16" drill bit on the holes and they allmost dissappear during the fibreglassing.

I tried the zip ties at first but like you, I don't like the big holes and no matter what I try, I just can't seem to match the colour of the ply with woodflour.

Black wire will be fine. We can't buy that here. The gal stuff is available and cheap, so I use it.

Posted: Sun Oct 07, 2007 7:30 am
by FlaMike
Thanks for the replies, I've got a good idea what to look for, now. I've seen the stitch hole drilling jig in the "Tips & Tricks" section and I'll make up one of those as soon as I know the design specs on the hole placement.

Mike S.
Spring Hill, FL

Posted: Sun Oct 07, 2007 8:19 am
by hairymick
About 9 inches works for me. :D

Posted: Sun Oct 07, 2007 8:45 am
by Oldsparkey
FlaMike , Go to a Ace hardware store and get the roll of copper wire .20 (I think) It is just a shade smaller then a 1/16th inch drill bit.

Cut the wire into 3 inch lengths and use it to stitch the panels together. I use it and can have the wood on the panels butting up against each other so when a small line (bead) of epoxy is ran over the seam it bonds together without any dripping threw the seam , yep they are that tight when done right.

When the panels are together and if there is a bump that needs to be reduced to make things fit , some sand paper (folded back to back so it is gritty on both sides ) put between the panels and ran down the seam will remove that bump. Be careful , you only want to remove the bump or rise not the rest.

Then when you glass the boat the holes almost disappear but the seam being a continues line is visible.

"O" get several of the 1/16 bits , they break real easy and you should need two or three rolls of the wire depending on how far you space the holes.

Chuck.

Posted: Sun Oct 07, 2007 8:59 am
by FlaMike
the wood on the panels butting up against each other so when a small line (bead) of epoxy is ran over the seam it bonds together without any dripping threw the seam , yep they are that tight when done right.

I get what you are saying here, I think, but were you using any spacers, like those craft sticks I see in all the build pics?

I used a bunch of those sticks to mix epoxy with for my last build. Figured I'd get a couple more bags.

What exactly are we talking here? I'm guessing the idea is to leave a narrow, uniform space between the panels to be joined, without the panels actually touching. That about right?

Using the folded-over sandpaper to clear any bumps in those spaces sounds like an easy way to take care of that problem. Thanks!

Mike S.
Spring Hill, FL