Tanzer 16 Construction Notes and Repairs

Tanzer 16  Construction Notes and Repairs --  February 7, 2017

There have been several inquiries about repairing Tanzer 16 hulls and decks.  This page is a supplement to the many fine books and videos on small boat construction and repair.  I have repaired my boat, but I am not an expert.  Much useful information is available on the blog:  jimslittleboat.blogspot.com.  More information can be found through the Facebook page Tanzer 16 owners.  Many of these owners have done far more extensive repairs than I would contemplate and they are an excellent source of information and inspiration.

Like most small boats, the Tanzer 16 hull was built in a mold.  There were  at least three sets of molds since the boats were built at the original Tanzer site in Quebec.  Some hulls were also built in Arlington, Washington (the state), and New Bern, North Carolina.  To create the mold, a plug was built (usually out of wood).  Then the molds were made from the plug.  As a result all of the molds should have been pretty much identical.  It is likely that there were differences in some details of construction at each site.  (For example my boat, 1306, (incorrectly listed as 1360 in the diagram) has foam blocks inside the seat air tanks.  Others have reported plastic bottles inside the seats.)

Generally Gelcoat is sprayed in the mold first.  This gives the hull it's color.  Then glass, resin and intermediate substrates are sprayed and hand laid into the mold.  In the same way the seats, forward air tank and deck are created.  Then everything is joined together in this order.

It is quite common that, over time the seats tend to become separated from the hull.  Cracks develop from the flexing and torsion of hard sailing.  If there is no rot in the floor, this is an easy fix.  Just grind (sand) away the finish in the tab areas and add new tabs.

On the inside of the hull and seats the builders used small blocks of 1/4-inch plywood.  By using these small blocks they were able to conform to the curves of the floor and seat using straight material--like tile in a shower floor.

They were butted together in a running bond to make up the surface.  Like so:

When you cut into your boat, they look like this:

This is a nearly completed floor repair by another owner.
I would give him credit if I could remember where I saw
it.

The blocks inside my deck had delaminated because they were placed in the
resin after it had started to set up--a factory mistake.  I was able to re-use
some of them and I cut others from exterior plywood.  A sheet of marine
grade fir would have cost more than $100 and I needed less than a square
foot.  The seat was wrong the day it left the factory.

This is what my seat repair looked like after I replaced the blocks.  Before
I could do this I added a glued in backing plate underneath.

On my boat the deck is made up of 1/2-inch marine grade plywood with a substantial amount of glass build-up on both sides.  There is a support beam down the centerline of the deck.  We discovered this when we cut a hole in the deck to mount the spinnaker launching chute.   It is reported  that early versions had thinner deck material and therefor had a king post to support the deck.  I have examined a number of Tanzers, but they all came out of the Arlington plant and all of them had the thicker deck.

We were pretty surprised to find the deck was so solid.

I hope this information give you a basis to plan your repair and look for further information.  In general you will want to plan your repair so that you remove the inside of the hull or transom.  It is much more difficult to do your repair from the outside in.  jim