Hi, started a build with no solid plans. Built my strongback, laying out the ribs, got the spacing but hoping someone could give me a idea what to go with for the height for the side ribs. I`m thinking 2 ft (or less) in the frt and tapering smaller to the transom? (but how much). Does that make sense to get 2 sides out of the 4` ply?

Also someone suggested I dado the ribs so I started doing that. I got 2 done and decided it was a bad idea when it comes time to attach the chine with no meat to screw too. Any thoughts?

Can anyone suggest how high to set the ribs for the rocker, I`m guessing starting in the center? Thanks much, Mike

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Mike,

When you "glue up" the frames apply a thin coating of mixed (105/205) epoxy to the mating surfaces to wet them.  This will allow the epoxy to leach into the wood fibers further than the thickened epoxy.  Then add filler to the remaining epoxy to thicken it up some ( like mayo). Use this to coat the mating surfaces then clamp them together.  

Use the thickened epoxy to make sure all the gaps are filled. You may want to add a little more filler for this.  Do this before you coat all the components as I mentioned earlier.  The final epoxy coatings should seal pretty much everything.  

Oops, I just realized you had already glued the joints. Disregard the above, Duh!

I'd make sure all holes were plugged with this same technique as above, if your using dowels.  The epoxy joints of the frame members (half laps) are almost as strong as a screwed and glued lap joint, and more than you'll need for the structural strength needed.  Glued in place dowels will pretty much keep water from migrating in the wood.

I like Your stem plan it'll work, however the cherry won't be visible after you put a deck above it.  The intermediate piece (ash) could be cherry too, that'll show .  The last frontal piece of Ash will add some needed strength.  Your going to bump into things from time to time.

Dorf

Thanks Dorf, I couldnt reply under yours so I`ll slip it in here. I`ll remember that wetting tip next time I`m gluing something up. I was kinda thinking about the top of the stem that will show, just to add some character besides the ash.

Made up some chine logs. Had to splice the rift sawn white oak to get the lengths I needed, glued them up with Tightbond III. Got all the frames notched for the chines, and drilled out my temp screw holes and plugged them with dowels. Next up I`ll sand everything nice and get a coat of 207 clear/105 epoxy on everything, then get to installing the chines.

Trying to bend that oak is tough. I had it bent some but had to remove them to do the dowels, and to sand and coat everything.

Got the guy down the road to run my mahogany and walnut through his planer today for the transom. Going to run a strip of walnut up the center, 1/2" white oak stripe on each side and the mahogany on the outside so I`ll get working on that this week too.

Epoxy won't self-level; expect to sand a bit to fair the surfaces. For frames, etc, I would apply the epoxy with a 1/8 " foam roller - the yellow ones. Cut a 7" in half and use it on a small roller frame. If you have any frames that still need their first coat, you might want to consider thinning the epoxy with lacquer thinner (but check with West System instructions about thinning). This will help the epoxy soak in. You are going to need to top coat the epoxy with UV protection - paint or varnish. You may not need two coats.

Eric,

I assume you are referring to West System's Foam (color yellow) rollers you cut in half.  They work good and hold up through several applications made in a day.  The little diameter (about 1" dia) foam rollers sold at big box stores don't!  The epoxy breaks down the glue used to bond the foam to the core which is usually plastic. and they are useless.

I don't think West Recommends thinning their epoxy, but you can warm up the resin somewhat and achieve the same result but you lose working time when you do that.  I have never felt the need to thin it in building a new boat.  You might need/want to when repairing or restoring an older boat with dry rot and similar problems.  If needed, wouldn't it be better to replace those problems with new wood?

Just another two cents worth.

Dorf

Mike,

Having used Titebond III to glue up the frames I'd recommend that you coat them with a minimum of two coats of epoxy.  The reason is; the epoxy is the only means to keep water out of the wood and glued joints.  TB III is water resistant not water proof.  If enough moisture (water) gets into the joints they will eventually fail.  The strength of the joints with Titebond III isn't suspect, it's it's ability to stay dry just like they are now.

Dorf

Dorf

I'm interested in waterproof wood glues, since I'm starting a build. Titebond III claims Type 1 waterproofness - while investigating this standard, here's what I found:

What is the difference between the ANSI/HPVA Type I and Type II water-resistance specification?

Both of these tests are conducted using 6” by 6” birch laminates glued together to make three-ply plywood. The test for Type I is clearly more stringent than Type II, and involves boiling the glue bonds and testing the specimens while they are wet.Type I testing involves cutting the 6" by 6" assemblies into 1" by 3" specimens, boiling them for 4 hours, then baking the specimens in a 145°F oven for 20 hours. They are boiled for an additional 4 hours, then immediately cooled using running water. The specimens are sheared while wet, and the bonds must pass certain strength and wood failure requirements to pass the Type I specification.

I'm looking for a glue that would hold it's strength through the steaming process - from this description, it seems like Titebond III would work - your thoughts?

Wow, good info. Hey Dorf, I glued the frames together with the 205/105/103 microfibers. I just used the TightbondIII to glue the dowels in, little easier to deal with than the epoxy. They are sealed in real good now with the 207/105. After sanding the frames, I applied a 2nd coat to them, wow, smooth and shiny like they are coated with glass, though like was said the epoxy doesnt spread all that great, and theres a few small runs here and there, but no big deal.2nd coat added some deeper color to the DF. Theres gonna be some different colors with the woods, but it should look ok.

Triimed off the chip brushes as suggested and they work so much better than the foam. 1 Chipbrush did all the frames where as 6+ foam brushes to do the same amount. I only mixed 1 pump from the 105/207 cans in a cup at a time and that did about 2 frames.I sanded and 2nd coated the chine logs today, I`m gonna call that good and start building again maybe tomorrow. I put the epoxy on the cherry stem pc and wow is it pretty. It will only show from the fly line deck up but thats ok. I mainly needed a decent chunk of wood for the stem, so 2" of cherry and 2" of ash glued together will do it. Do the chine logs need to be glued into the notches in the frame beside the stainless screws? Its June and suppose to be in the 30`s tonight, WTH,lol.

David,

If your building plywood I think that Titebond III will work, based upon the information you posted.  If your building a boat; remember it's a hole in the water, sits in the Sunshine and exposed to the Weather a whole bunch and it gets banged around quite often.

I used epoxy, as I described above, to glue all my framing together.  When you look at the big picture, the cost of the epoxy and effort to apply it, it becomes a small portion of the cost of building a drift boat.

If your thinking of using Titebond III to scarf together chine logs and other long elements of your boat, It'll work.  I used Titebond II on my Cedar Strips, chines and sheer rails on the DB, but they are encapsulated in Glass and 3-4 coats of epoxy.  

If you'll then be steaming them you only need to steam the pieces one hour per inch of wood thickness, normally.  I think you'd want them to be waterproofed (epoxied, oiled or something) before you permanently attach them to the boat

Dorf

I did use the Tightbond III to scarf the chine logs together, but they are now coated with epoxy, 2 coats. I`m hoping they will bend ok without steaming, I`m gonna start that tomorrow and let that 2nd coat of epoxy dry good over night.

So the spliced chine logs held up just fine, but I did locate the splices towards the rear between 2 frames that had less stress than the forward frames. Even with 2 coats of epoxy, they did bend ok, though it took a little oomph to get them to bend.

I started screwing them on with the screws through the top at a angle as suggested in the Tatman book, but it was not working out well. I opted to put them on the outside edge going in at a angle and it worked way better to draw the chines into place. I ended up having to adjust a couple of the frame notches to get the chine to fit better, and still have to work on the stem a little. I did touch up the notches on the transom frame and screwed the chine on. I started to flush cut the chines off at the transom, but stopped part way into my first cut and decided to leave them long for leverage, as I need to remove them and set them in epoxy for the last time.

Started cutting some wood for the transom. Walnut center/white oak strips/mahogany on the outsides. I laid some scrap over it just to get a idea of he shape/size. I plan on a slight curve on the top of the transom. Not sure why the pic  posted upside down. I`ll joint them together, plane and sand them up and set it aside till I get the plywood on.

Unrelated, I made a couple oak rod racks

So I think I got a step mixed up. I think I need to trim off the chines, then install the transom board, bevel the angles, remove it, coat it with epoxy, reinstall it then run the plywood onto it. In the end the outside trim will go on the back. I guess I`ll be doing that next. Whats the best way to install the epoxy covered transom to the epoxy covered transom frame? I know I can perimeter screw it together (screws will get covered with the trim) but should I get and use the 5200 for that and the screws?

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