Some emails cause our hearts to skip a few beats.

Checking in from our cross-country road trip. We stopped by a lake in Colorado a couple of days ago to take the PT11 out for a sail and noticed something very alarming... The back seat buoyancy tanks have bowed - like the air in the tanks expanded. They have returned to the normal shape again, but the fiberglass strips on the tank joints probably couldn't handle the pressure and have cracked - see pictures attached.

This boat was built at sea level in NYC and the tanks were expanded at roughly 10,000ft. The good news is that they did not explode nor do they appear structurally compromised, thanks to wood/epoxy as a construction method.

Most of our clients have used their boats near where they built them but others have taken their boats from sea level proximity to higher altitude lakes. (These two videos are thanks to Randy and Kim Kerr)

https://www.youtube.com/watch?v=jdLN_QaQrv4. Ross Lake (1,519 ft)

https://www.youtube.com/watch?v=LJV8MJJv6pU&t. Chilko Lake (3,845ft)

Randy replied to my inquiry about his lake trips: "We've never really taken our PT11 higher than 4000' and didn't notice any bulging in the buoyancy tanks personally.  I could imaging customers that span 10K feet in altitude difference could easily see bulging or compressing."

Because Russell and I initially imagined our boat builders using their PT 11 dinghies primarily for ocean cruising, the influence of high altitude on the air buoyancy tanks simply did not come up but once in 15 years. That customer installed a relief valve but we never heard exactly what type or how well it worked. We imagined that as a one-off but we are also under the constraints of the USCG rules that prohibit access ports or any compromise of a sealed air tank if it is to be counted as buoyancy. Hence we moved on.

Times are changing however, and it appears that more PT 11s are on road trips and out lake sailing so, it seems prudent to address the air pressure question for anyone planning altitude differentials of more than 4-5000ft with their PT 11 or SPEAR dinghies.

There is an argument for drilling a 1/4" hole on the vertical face of each of the three air buoyancy tanks and filling them with thickened epoxy. (This keeps moisture from reaching raw wood.) If you then notice any expansion at altitude, you have a safe spot to drill a very tiny hole to relieve pressure. The hole could then be taped over until the boat was back at its normal altitude when the new hole could be filled. You would have to choose a time and place with a stable temperature to fill these holes.  In an emergency, go ahead and drill tiny holes to keep damage from occurring. Just know that refilling those holes in a way that keeps the wood dry will be important.

One builder currently working on his PT 11 is planning to use it almost exclusively on mountain lakes and had already researched the pressure valve question before I reached out to ask about it. Have you heard of Gortex Dots? He has generously shared his in depth research and conclusions in this PDF article. An Idea for the Vented Volume Dilemma

The standard rule should still be noted for air buoyancy tanks: no access ports or compromise of the seal unless you plan to fill the voids with flotation foam. These dedicated air tanks (forward of the mast step and the aft seat boxes) are not intended as storage and using them as such could present a serious safety risk if you flood the boat. If you truly need to modify the design to fit your intended use, how you manage that is your responsibility, so be informed, do your own research,  and think 'safety first'.

June 2025 UPDATES

A PT 11 builder came up with an elegant solution to the venting option but it a manual vent, meaning, you must manually open the vent (a screw installed into the back seat glue cleats and the mast step) if there seems to be pressure building up and close it once pressure is relieved. PT 11 screw pressure valve info1.(1 page PDF)

The second update refers to a system that FYNE BOAT KITS in the UK uses for most of their kits. They point out that not only elevation but temperature extremes can cause issues with air buoyancy tanks. Gore-Tex-Vent-Installation

Here is a link to the vents Fyne Boat Kits (UK) sells:  https://www.fyneboatkits.co.uk/accessories/surfboard-paddleboard-accessories/gore-tex-vent/

Boat building is a creative process. With our kits, it may be said the Russell has thought of 'everything' and thus, the margin for builder inventiveness is limited. I beg to differ and I have great faith in each person's ability to creatively personalize their boats! It is also our hope that the building experience in itself serves the creative spirit well and the end result is a boat that makes the builder proud and happy. It is difficult to make guarantees, and especially so if any part of the design and/or the described building method, is omitted or modified.
In reference to some questions we have received ;
Flotation vs Storage;  about the PT 11: The three compartments, one in the bow and the two in the stern, are completely sealed flotation and have the same value as foam flotation in this type of boat. If access ports to flotation compartments are installed, equal foam flotation would then be required to replace the sealed air. This would be a lot of work and totally pointless. Trying to use designated flotation compartments as storage can be dangerous if the boat flips or floods. On the PT 11 & Spear, there is a large storage aft of the mast step with ample space and the PT Skiff has 3 separate storage areas. We had to calculate flotation for the PT11, the non nesting PT SPEAR, and the PT SKIFF in order to satisfy the USCG safety guidelines. It is the builder's responsibility to abide by those rules, and, it is just plain smart.

Re-enforcements; Any additional wood or glass than what is prescribed in the manual, serves to add weight and will not necessarily make the boat any stronger than designed. Our boats are already designed with heavier glass on the bottom and solid fiberglass caps on the skegs for added toughness. If it is expected that the dinghy will be typically dragged over rough landings rather than carried, one could beef up the fiberglass on the bottom further, but it will add weight.
The transom, as designed, is strong. The rudder is a kick up rudder so there should be no chance of ripping off the transom of the boat with this rudder. If you plan to use a small outboard, (max 2HP) you would use bearing strips on the outside and clamp pads on the inside.
Builder resources; Our PT 11 family is growing. This is very exciting for us as we are a small company of just Russell and myself. Even more exciting is that our customers have been building beautiful boats! This year, 2013, we  established a registry of sorts (see the map) as an owner/builder resource and aim to create an interactive community. (see our Builder  Center page) The questions, comments, shared experiences of each builder are all welcome material that I will look forward to adding to the blog for others to learn from and enjoy.  Our heartfelt thanks to our customers, followers, and friends who share their opinions and enthusiasm about our products. We would not be here without you.

PTW Ashlyn

Weighing in lighter than expected at 340LBS.

MARCH 08, 2010

Following are pictures of the hull glassed and the final gloss coat finished. We are ready to paint the hull this week.

FEBRUARY 18, 2010

A bunch of good friends showed up to turn the skiff over. Thank you!

February 14th, 2010

Happy Valentines Day World.

Progress as of today.. All inside structure and finish work is complete. We are ready to turn the boat over and glass the bottom.

January 25th, 2010!

I know! I know! I am getting slack with blog posting! Well, dang... It is not like there hasn't been a whole lot happening!

Today I am posting a shot of the CNC cutting that happened on the  15th and a couple of shots of the recent final coating of the inside of the PT SKIFF. We have decided to keep it clear coated as this boat is our showpiece and people have really loved the clear finish. Further, the construction techniques are clearly visible and it helps people get a good picture of how the boat went together. So here goes...

Paste this YouTube link into your address bar to see a brief clip of the coating..  http://www.youtube.com/watch?v=nGyaVfV-yeo

JANUARY 1st, 2010!

Happy 2010 to all! We are back online again ...

All 3 seat tops ready for final installation. Almost all surfaces have been glassed and are ready for the final gloss coat of epoxy.

Cheers for now...AE

DECEMBER 28th, 2009

HOPE EVERYONE HAS ENJOYED THIS LAST WEEK! I know we have not updated recently but that does not mean progress has not been made between entertaining friends and family and being entertained. We will be uploading new photos shortly of the console and drivers seat in and the forward floor in and more. Wishing all a HAPPY NEW YEAR and may 2010 be a positive year for you!

DECEMBER 20, 2009

DECEMBER 8, 2009

This past week we finished glassing the chines and have been making the patterns for, and cutting the lumber parts for this boat and at least 5 more kits. Pictured below are the glue-cleats placed near their positions.

DECEMBER 2nd, 2009

Filleting and taping the chines..

NOVEMBER 24th

NOVEMBER 23

New pictures and more to come.

NOVEMBER 16th,

Progress is being made! The next set of pictures shows aligning the stem, topside panels and sheer clamps, transom inwhales and side decks prep.

Updates are happening weekly so please keep checking. We could easily be twice as far but the manual is specific and comprehensive and all will no doubt agree, worth the time taken to create it. Cheers..AE

November 10th

Over the last couple of weeks, we have made a lot of progress even though we are working on the builder’s manual more than the boat.
Pre-finishing parts is a large part of the job in the beginning of building this boat.  This stage goes really fast on the bench and means very little finish work later.
The assembly goes really quickly thanks to the tongues and slots.  Here are some pictures of where we are to date and we will post more in the next few days.

November 1st.

Pre-finishing parts is done and the cradles are ready. This first week of November will see the skiff get wired together.We have been able to refine much of the building technique with this skiff so that the manual reads better and your building experience will be easier.

Pre-finishing is the first part of building the PT Skiff.

Building has begun. See here all the ply parts cut.