August 2013

I have been very busy this month and although I have done a bit of work on the boat, I have not had time to tell you about it.  I'm going to go through the process of installing one of the cold molded strips on the hull not that I have gotten the hang of it.  

The fist thing that is done is the strip is laid onto the hull close to where it will be installed.  There should be at least 1.5" between the new strip and the installed adjacent strip.  There should also be about the same space at the to as the bottom.  The gap in the middle will be different than at the middle. Hold the strip in place so that it can still move around.  Start clamping at one end and move toward the other making sure that the strip is laying flat against the longitudinal battens.  You may have to adjust the entire piece and restart the clamping pressure if the strip wanders to close or too far away at the opposite end.

Strip clamped into place.  There are fewer clamps between the strip than on the outside because that is where I need to mark the cut line for the strip.  Use enough clamps so the strip lays flat on the longitudinal battens.

I've modified an old marking gauge for the next step.  I drilled a hole in one and cut a slot so that a pencil will fit securely in place.  A screw and wing nut holds the pencil in place.  The marking gauge is slid along the last installed strip while marking the temporarily installed strip.  The idea is that you want the these two pieces to fit together so you mark an equal distance from between the two.  Make sure the marking gage is set slightly wider than the widest gap between the two pieces.

Checking that the marking gauge is set just wider than the wides gap between the two strips.

Sliding the marking gauge along the gap to mark the cut line.  Normally I use two hands for this.

A power saw was used to cut the waste off the strip.  I cut to just before line.  I then use the hand plane to finish the cut. This leaves a beautiful clean edge.  

Once the strip is cut and finished, I re-clamp it in place.  I usually have to use a few temporary screws to hold down the edge where it mates with the last installed strip.  I make sure every thing fits nicely and that there are no overly warped places of gaps.  These are caused by either forcing the strip to bend closer to the installed strip or by a strip that is too wide.  Reposition and remark or rip the outside down an inch.  Make sure you cut the outside and not the nice curves side you just made.  Look for gaps that are larger than your thumbnail.  These usually can be fixed by a little hand plane action.  Most of the strips installed so far have needed a little cleaning up in this way.  The strip sits on a slightly different curve because it's closer to the last strip than when you measured it.  This can't be helped.

Once the strip fits nicely, mark all the longitudinal battens along the outside edge.  This is where you will put epoxy.  Remove the strip and set it aside.  I mix my epoxy for this procedure pretty thick by adding silicon filler.  This helps it stick to vertical surfaces without running off.  I'm also pretty liberal with the epoxy since this is a critical junction in the construction.  Make sure you edge glue the strips as well.  Lay the strip on the wet epoxy and start the stapling process.  I use 1 1/2" stainless staples with a 1/4" crown and a pneumatic stapler.  I start about 1/3 up from the gunnels and make sure that the strip is tight against the previously installed one.  Some bulging may occur between longitudinal battens and for this I staple a short 1X4 parallel to the batten about half way between on the joint.  I use wax paper between the board and the strips to prevent them sticking to the epoxy.  Occasionally I need to use a temporary screw into the back of the strip to either side of the joint to make sure the two strip's edges come together flat.  This will prevent one edge from being higher than the other.  This is why edge gluing is important.  I also brush epoxy down the joint between the two strip to ensure a good bond.  Once the epoxy is cured then the edges will hold together and the hull will be fare. I use a belt sander to take off any high spots and the excess epoxy at the joint.  Don't forget to remove the temporary screws.

Strips five and six being installed.  Note the temporary horizontal boards that are ensuring that the edges remain flat together where there are no battens.