Scarfing post mortem

Ok.  I admit defeat on scarfing the panels.  After fairing and filling the first two panels on for the bottom, I have decided to just do the fiberglass scarf joints as outlined on the plans.  I did my Michalak skiff this way, and the seam is not noticeable to the uneducated eye.  I figure that if I need to sand and fair, I might as well make it easy.  Hope to get the foward panels on the bottom this weekend and build the sides as well.  the switch to standard stitch and glue should speed things up.

Also was slowed down by work, weather, and some damage to the transom on the Bolger 18 workskiff.  (nothing serious, just a hairline crack in the glass where it had not adhered well.  No water present!)

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Core Sound Start 6 9 13

 9 Sheets of 6mm Okoume
3 sheets of 9mm Okoume

by noon, I had all the 9mm ripped and ready for gluing the scarfs.  I use a makita Power plane to rough cut the 3" scarfs, and then a block plane, followed by a belt sander.  This took 30 minutes tops.

Next will be to move the panels to the basement workshop for gluing in the climate controlled environment!  I use WEST with one primer coat, followed by a thicken coat with Cabosil or equivalent to make a bonding putty.

I place a wide sawhorse under the joint, then cover with plastic, apply glue, then cover with plastic, and lastly     weight down with a 1X6 with any kind of weight on top.  If it slips too much, I will drive a couple of bronze nails through the set up.  May do this anyways to save time.  the goal is to be able to loft the bottom panels next weekend, and then start on the sides.

Here I am 3 hours later.

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The Utility part 6 Fixing the chines

I made a common mistake when I installed the chines. Sure, Id read about the possibility of making this mistake beforehand. However, I obviously didnt "get" it. Happily, its a common mistake with a fairly simple fix. Im going to share all this with you in hopes that the new builder might avoid this pitfall.

The mistake is: not getting enough twist in the forward section of the chine log.

The resulting problem is: inadequate twist in the forward section of the chine leaves you with NO SURFACE AREA for the side planking to mate to.

Heres an image to help illustrate:

You see, after the chine and sheers are installed, both of these pieces are faired. The forward section of the chine is basically beveled along a line running down the middle of the wood from the stem to the forward frame. The upper (top-side) section of this bevel is where the lower edge of the side planking will attach. The top-side edge of the planking will attach to the sheer (shown as the dashed white line in the photo).

If you do not put an adequate twist in the forward section of the chine, then the resulting angle will not point outward adequately to the sheer line. This problem is illustrated by the dashed red line in the photo.

To avoid this problem, be sure to twist the chine adequately in the direction shown by the green arrows before you permanently attach the chine to the stem & frames. I did not twist mine adequately, because I thought the wood was going to break. So what. Soak it, steam it.... whatever you have to do to make it twist enough. Otherwise, youre going to have a problem to fix — just like I did.

The Fix:

The fix is: add a wedge-shaped strip along the top-side half of the forward chine, so that youll have an adequate angle toward the sheer & enough surface area to attach the planking to after fairing.

The Utilitys chines are 2 inches wide. The distance from the tip of the stem to the forward frame is 4 feet. So, I ripped two 1-inch by 4-foot sections of wood from the remnants of my first chine log (which broke because I didnt steam it).

I placed a straight edge from the chine to the sheer, and measured the angle. I then beveled my new "chine strips" so they would angle 20 degrees outward from the surface of the installed chine log. The resulting strips were fairly thin.

Cross-section of the "chine strip" after beveling it 20° on a planer / jointer.

I then epoxied these strips onto the top-side half of the forward chine. They were a little long, so I had to trim them. They bent easily since they were so thin. Now, I should have an adequate surface area for fairing & attaching the side planking.

Forward end of the attached chine strip, trimmed along bow line.

Aft end of the chine strip at the forward frame. This will have to be beveled down to make a fair curve along with the rest of the chine log.

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