Building #759 (cutting out chine logs and side panels with a template and a router)

I first learned of the PDR while looking into the Texas 200 (something I still hope to participate in).  I read about all these guys in these little home made boats going out and doing what everyone said was impossible.  It REALLY sounded like fun.  So I started to investigate this strange little boat.  The more I read about it, the more I liked it.  Now I know a little about sailing and a little about boats in general.  I know a little (not much) about wood working and have some general tools.  I've never built anything as big as a PDR or even considered that I might be able to build a boat.

After reading up, downloading and examining several sets of free plans and learning as much as I could without having ever seen one.  I decided that a 1/4 scale model would be a good starting point.  It would let me get a feel for the construction techniques and when complete it would give me a better idea of just what one of these boats would look like.  I spent about 1 week, working for 30 minutes each day to cut the sides, attach chine logs and glue on the bottom.  I then had a 1/4 scale "3D" Puddle Duck Racer! (Would 1/4 of "3D" be "3/4D" ? )  Here is a picture of the 1/4 scale model sitting on top of the full size Duck.

I learned a few things during that "micro" build:
First, my side panels were all different shapes.  I tried to cut them out in pairs but it didn't work well and no matter how much I sanded them, I could not get them to all look the same.
I could not bend the "chine logs" (1/4 round molding) without cracking them.  I ended up with a bunch of 2" long pieces.
Getting the bottom to accept the curve on the bottom without cracking was an issue.
It wound up very "out of square".
I know that some of the issues were due to the fact that while the boat was scaled down, the building materials were not (1/4" birch and 3/4" "Quarter Round" molding), so it is not REALLY a fair comparison.  But I feel like I learned a lot from the exercise.

Of all of that, getting the sides to match and getting the chine logs on worried me the most.   I knew that I needed to find a better way if I were going to build a full size boat.  I spent a long time thinking about it and finally decided that I needed a template to use to cut them out.  After talking to a bunch of people on John Kohnen's Yahoo group , it seemed that I needed to use a router to do the job.  I didn't own a router.  I had never used a router.  I wasn't even sure exactly how one would work.  But I didn't let that stop me.  I ordered one on-line and was determined to make something happen.

Even before I bought the router I had gotten together with a couple of others in the Houston area who were interested in building PDRs.  We went on a field trip to look at a mostly complete boat someone else had North of town.  We even got as far as going to buy wood, but after trips to several Big Box stores we could not find a decent sheet of plywood if our lives had depended on it.  After some research I decided to buy some REALLY Nice marine plywood from Houston Hardwoods for $40 a sheet.  I wasn't THAT much more than birch at HD and the difference in quality was HUGE.  Plus marine plywood is not supposed to have any voids and should use better glue.  So I went and bought 3 sheets and got to work.

Here is what I did:
1. I made a template for the side panels:

2. Next I went to Houston Hardwoods and bought three sheets of "AquaTek" 1/4" marine plywood.

3. I cut the chine logs.

4. I cut the side hull panels:

5. I glued the chine logs onto the side panels.

Assembly of the side and end panels was pretty straight forward. Nothing different than what is documented elsewhere. I did have one more idea that I wanted to try out. I thought that if I used Taper Head Brass Screws and counter sunk them into the 1/4" plywood bottom, I would be able to leave them in place.  Unfortunately I soon discovered that if I drilled the counter sunk hole deep enough that the brass screws would be flush, screwing them down enough to pull the plywood bottom into place would pull the screw through the bottom.  I handled this with bigger screws and fender washers in those places.  I still pre-drilled the holes but I did not try to counter sink any more of them.  After the glue had dried, I went back and removed all of the screws and glued pieces of skewers in their place.  Next time I will use pan head screws and plan on taking them out.

I am VERY happy with the final product.  The sides mated with the bottom so cleanly that I expect I could have put it in the water with no more work and it would not have leaked.  The pieces fit together MUCH more precisely that I had even hoped they would.