Diesel Duck 382

Diesel Duck 382
Diesel Duck 382 with the "get home" steadying sails up.

Wednesday, March 1, 2017

A prop shaft runs through it

We had a very nice vacation but I was eager to get back to the shop.  Our flight home was very early so after arriving, making a quick trip to the grocery store and grabbing lunch, I was back working on our project by noon.  It's been an unusually warm winter here in upstate NY and on the day we arrived home it was close to 60 degrees.  I decided to take advantage of the warm weather and try to address the condensation issue in the boat shed.  I added gable vents to the East and West sides of the shed.  Install was simple with a circular saw and a multi-tool.  I secured it with a few screws.  So far, so good but I'll need to check on a really cold day to see if its actually making a difference.

I then got started on dadoing out the grooves in each half of the chine log.  Each half required a 1 3/8" deep by 2 3/4" wide groove cut from the very center of each.  I did this on my table saw with a stacked dado head cutter.  I set up a  5/8" stack and cut the full depth of 1 3/8" in a single pass.  This is a lot to ask of your table saw, so if you have anything other than a 3hp saw you'll need to make multiple passes working up to the final depth.  Once the dado's were cut, I cleaned up each groove with a hand plane and then applied two coats of epoxy to waterproof the wood.

The next step was to glue up the chine log to its final dimension.  I chose to use resorcinol glue again as this piece will live the majority of its life underwater and I wanted to use a completely waterproof adhesive.  The most forward section of the chine log will be through bolted to the keel so that will add some additional holding power to assure it never comes apart.  It's the belt and suspenders approach to building that I am a big fan of.

The glue up went smoothly, and like the previous glue up, I used several clamps at very high pressure.  Once it was set in clamps, I ran a long batten down the inside of the newly formed chine log and scraped the glue squeeze out from each side, just to clean it up a bit.  The finished dimension of the shaft log is 2 3/4" by 2 3/4".

I tried to be a little more judicious in my use of adhesive in order to minimize the amount of squeeze out and it worked out well.

A few days later I un-clamped the assembly and brought it out to the boat shed to make room for the next glue up.  The stem and transom knees were next and were quite simple.  I simply laid out my patterns that I made on the red rosin paper and began cutting 2x8's and stacking them, cut to the length that covered the pattern.

I marked each with a reference line so I could ensure repeatability when I did the glue up.  For many of the keel components I am choosing to use epoxy.  There is no perfect adhesive but epoxy comes darn close.  It's strong, easy to work with, sets up in a wide variety of temperatures and is nearly water proof.  However it does have its weaknesses.  It starts to loose strength at temperatures over 120 degrees (depending on manufacture) and it is not rated to be completely waterproof.  

In this application where these keel components should never be submerged (I hope) and should not be subjected to high temperatures, like pieces on deck in direct sunlight, epoxy will be an excellent adhesive.  Additionally, these knees will be bolted to the various keel components they are designed to support.  Belt and suspenders again.

I mixed up batches of epoxy as I went and applied the adhesive to each face of the pieces to be joined.  Epoxy only requires moderate clamping pressure, so I only applied pressure up to the point where squeeze out began to appear and the joint appeared closed around the entire piece.

I had to clamp up in sub-assemblies in order to keep them within the limits of my table saw to be cut to their final width.  I ran out of epoxy and clamps to do the second knee so that will have to wait.

Next up was preparing the framing table for lofting our frames.  I set up a straight edge along the base of the table with some scrap plywood in order to have a clean edge to catch my tape measures.  I joined each edge of the plywood so it was perfectly straight and then cut a parallel edge on the table saw.  I also used more scrap plywood on each side of the table, perpendicular to the base line.  These will act as clean, straight edges to hook my chalk line to.  Again, I joined one side and cut a parallel edge on the table saw.  I was careful to ensure the side pieces were exactly 90 degrees to the base line.

I then went ahead and laid out half of station 26 using the table of off-sets. If you click on the picture above you can see the lines that I laid out.  I'll get into the specifics of laying out the frames next time.  If you want a sneak peek of that process you can check out season 1, episode 7 on our YouTube channel that will be online Saturday March 4, 2017.

We've had over 15,000 views to the site since October and we are grateful for all the support.  Please check out our YouTube series by following the link at the top of the page or by clicking HERE.  If you have questions or comments don't hesitate to let us know.  You can send us a message on the link at the top of this page or email us at contact@seadreamerproject.com

Thanks again and we'll see you next time.

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