EPOXY Lessons series preview on Off Center Harbor (membership recommended to view in full. Builders of the PT 11 or Spear: Contact us for exclusive access)
SCAMP Hatch instructions Plywood SCAMP hatch kits are not available from PT Watercraft. These instructions may provide a loose basis for making your own.
We are ever grateful and appreciative of the care PT 11 builders put into their projects and then to receive photos and updates on progress & adventures is such a huge bonus. Here are some of the images received in the second half of 2024 as well as a reference to a Lattitude 38 article recently published.
See UPDATES at the bottom of this article. (June 2025)
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)
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."
basic air pressure illustration
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
FYNE BOAT KITS in the UK has been producing Chesapeake Light Craft kits for over a decade. They have wanted to produce the PT 11 for equally as long but we had not figured out how to make that work.
With the collaboration of Chesapeake Light Craft, and a stipulation that almost all parts be produced on the Eastern side of the Atlantic to avoid hefty shipping costs and import duties, progress towards this goal has been made. Fyne Boat Kits has spent valuable time and energy over the last 2 years to source and procure what they need to make an authentic PT 11 kit.
It sounds like they have reached the point where they can start production of the PT 11 Nesting Dinghy kit by the end of 2024. This is a huge accomplishment and we tip our hats to owner, Phil Smith, whose dedication and persistence are truly admirable.
Click this image to reach FYNE BOAT KITS PT 11 page.
As of today, June 3rd 2024, this PT 11 nesting dinghy is listed for sale on Facebook Marketplace. These do not come up for sale very often. This boat is nicely built, lightly used, includes sailing options and oars. For someone who can pick it up in Washington State. Click the image to visit the full listing, see more pictures and contact the owner.
In the building manual for the PT 11 it says: "The PT 11 sailing rig is designed to be light and easy to use, not to be bullet proof." In developing this rig, weight and ease of use were the biggest priorities. "Hiking (sitting on the rail and leaning out) is okay for one person to do but not two. Sailing with two and having one person hiking and the other sitting inside is okay too, just not two sitting on the rail."
The PT 11 sailing rig arrives ready to use with all of its running rigging. One small item is up to you and that is the traveler line. This is the line needed to clip your main sheet to.
You can tie a line with a little slack, using the existing holes on the transom inwale to clip your main sheet onto that. This self steering blog post shows this method.
The traveler can be be made shorter as shown below by drilling holes about 7" from the centerline (14" apart). We drilled 5/16" holes and then applied a few coats of epoxy to the walls of the holes to seal the plywood.
The traveler line can be around 3/16 diameter and be held with stopper knots underneath the inwale.
A short PT 11 travelerThis image shows the tiller/hiking stick in the self-steering position. This is good for brief periods and works best when going upwind and only works when the boat is heeled.
When sailing, if you feel resistance on the tiller, check to see if the rudder is completely down or if you have caught kelp or other debris. Keeping the threads in the knob clean and greased is important. The threads in the knob are brass and the pin is stainless steel so it will corrode. A bit of maintenance will insure the knob does its job and keeps the rudder down.
For post-2021 kits, use the forward daggerboard cap turndog to hold down the daggerboard by closing it over the hold down pin.Pre-2021 daggerboards are thicker and shaped differently at the top. A loop of line at the right length becomes a hold down when captured by the aft turndog.
The Tack clips onto the boom as shown. (This image shows an older style gooseneck.)
The outhaul (asymmetric) snap hook clips into the clew and the outhaul line should be snugged through the v-cleat on the boom:
PT 11 Outhaul configuration during a regatta. Schooner Sir Isaac in the background.
The vang clips into the eye strap on the mast.
The vang controls the twist of the sail. Controlling twist is important for getting the most power out of the sail, but don't overdo it! Some twist is good but the boom isn't un-breakable.
When adventuring or in fluky winds, we carry our oars with the oarlocks in the forward sockets and the handles tucked under the bow as shown above.
If you are new to dinghy sailing, avoid this use of a slip knot on the main sheet. Unsuccessfully yanking the slip knot free in a puff is a recipe for capsize.
If you capsize when sailing, after righting the boat, make sure the mast is fully seated in the socket before taking off again.
If you are new to dinghy sailing, it is better to start in protected waters or when there is an onshore breeze, preferably steady but not strong.
Keep your weight forward for speed, but move aft in stronger breezes and downwind sailing.
If the water is cold in your area like it is on Puget Sound, wear a wetsuit or drysuit in case you end up in the water. Hypothermia is no joke. It is always advisable to wear a life-jacket/PFD.
Learn to stall, or "park" by pointing into the wind and letting the sheet go. When the wind picks up more than you feel ready for, or you have taken water over the rail and you are feeling a little out of control, this is a good way to take stock: bail, check your rudder and daggerboard for kelp, sort out lines, and take a swig from your thermos before heading off again. The sail will flap and make noise but that is not a problem. When you are ready, reign in your sheet, and continue or head for safety.
Every year we make a point of sailing in the Shipwrights Regatta in Port Townsend Bay. This event has a special history and purposefully invites our marine trades professionals to put their tools down for a day and remember why we do what we do by playing on the water.
Photo by Chance Bates
When we first entered the PT 11, we were by far the smallest boat. Not classified as a racing dinghy and of course, unable to compete with the 505s or Thunderbirds, we entered in the Cruising class. Sometimes that meant a single start in C-class of our 11 feet and up to 40 foot boats and more. Some times the C class has enough boats to divide it into 2 starts of under 30ft and 30ft plus.
As boat ownership has become more financially challenging for the working class and many of our retired marine trades people, the boats many of us own have become smaller and more often trailerable. While the economic realities of this change are frustrating, it has also meant that a larger number of smaller boast are sailing in the local regattas. The PT 11 might still be the smallest boat in the Shipwrights Regatta fleet but we are amidst more similar company which makes for some nail biting finishes!
My 2024 Shipwrights Regatta video features many of the other C-class boats as we sailed around waiting for our start. I was having trouble making my gloved fingers find the right buttons on our little waterproof Olympus and it was too chilly not to wear gloves. Several times I thought I hit record only to see recording start after I thought I had ended my shot. I gave up and just had fun.
* Update to this article: We have received positive feedback on a product calledTef-gel, used by riggers and boaters for the purposes of anti-galling and anti-corrosion in marine environments. We have not yet figured out how to get mini quantities into kits cost effectively but there are small-ish versions available in your local chandlery or online.
The PT 11 Nesting Dinghy Connective system is unique and it makes up a decent portion of the cost of the kit. After roughly 200 PT 11's sold to date, there have been very few issues with this connective system. In this article we are aiming to share some lessons learned about these parts based on customer feedback and experience. A brief description
Our key to easy and fast assembly (of the two hull-halves) is to separate the two main functions of aligning the two halves and joining them. The alignment hardware is molded from carbon fiber, but it is robust and affordable for us to produce.
The connective hardware, used to join the two hull halves as they are correctly registered by the alignment hardware, are CNC-machined from 316 stainless steel.
This hardware consists of threaded sockets bonded into the forward half of the hull, and sockets with threaded pins and knobs bonded into the aft half; these parts are pre-positioned in the structure. Clip rings ride on the pins to make them captive, and this system allows assembly of the boat in the water without leakage.
The manual instructs builders to keep the stainless parts clean throughout the process of gluing and painting the boat. It is after the boat is finished that we instruct builders to lightly grease their hardware. Here is where some additional explanation is needed.
A few customers have had a pin get stuck at some point in the completion of their boat. The why of this has been a challenging topic but when it happens, it is terrifying for us as well as for the builder and can be costly to remedy.
According to Wikipedia, "Galling is caused by a combination of friction and adhesion between the surfaces, followed by slipping and tearing of crystal structure beneath the surface.[2] This will generally leave some material stuck or even friction welded to the adjacent surface, whereas the galled material may appear gouged with balled-up or torn lumps of material stuck to its surface. Galling is most commonly found in metal surfaces that are in sliding contact with each other. It is especially common where there is inadequate lubrication between the surfaces." Why and What to DO:
So, the question is why do the pins sometimes seize and what do we do about it?
The why is a bit of a mystery to all of the experts. One recently seized after it had been greased, so it's not just the lack of grease. We could also change the material of just the pin but hundreds of these have worked fine in all stainless steel.
Tight clearances are probably the cause, but we think we need the snug fit in both the forward and aft sockets to keep the hardware aligned when it's being installed. We are opening up the tolerances a bit on the next run of hardware, but it looks like the best insurance is going to be using a never-seize style of grease, applied after your boat has been finished (to keep grease from screwing up your painting and finishing).
It seems that the seizing is mostly happening at the tail end of the building process, so apply Never-seize * when re-installing the hardware after finishing. Clean the sockets and pins and apply a tiny bit (with a skinny stick of similar) in the threaded sockets and in the aft sockets and rub a little bit on the shiny part of the pins.
If you feel anything like seizing when assembling your boat, STOP. Is there misalignment? If you back out the rest of the pins, will the problem pin loosen up? Do your epoxy shims under the alignment clips need to be block sanded down just a bit? Are the outside edges of your alignment clips contacting the bulkhead edges?
If a pin feels stuck, remove the knob using two wrenches; 14mm and/or 9/16" to remove the knob, nuts and washer.
Put two nuts together on either end of the pin and tighten them together very tightly with the wrenches. (photos below)
Stand the hull half on end so that a bit of penetrating oil * can be applied and run down into the socket. Now try tapping and banging on either end with a hammer and wrenching on the end with the double nuts. Remember that the pin can only be removed from the socket in the forward direction because of the captive pin clip.
Still stuck? Get in touch with us.
If the pin leaves any roughness or scoring on the inside of the socket, that can be removed with a custom tool. Here's how:
Take a short piece of 3/8" dowel, chuck one end up in your drill, wrap sandpaper around the other end, hit the trigger and sand the dowel down until it fits loose enough in the socket that you can wrap some fine (400 or finer grit) sandpaper around the dowel and have it just barely fit in the socket. The sandpaper can be spray glued and rolled tightly on the dowel before using it to sand away any and all burrs and roughness. Finishing with an even finer paper is probably a good idea.
Spray-glue a bit of sandpaper to a flat stick to remove burrs from the pin before cleaning, applying the never-seize, and re-assembling the hardware.
DIY tool for cleaning the socket after removing a galled pin.
Caring for your connective hardware;
-Keep it clean before and after installation.
-As soon as grease is no longer a threat to gluing or paining, grease or ant-seize your hardware.
-At the first sign of binding, stop and assess alignment and possible causes.
-Refer to the chapter in your manual titled: Re-ASSEMBLY of Connective Hardware (p.288) including installation of the alignment clips. Precision parts require precision alignment.
-After a season of use, consider removing your pins, clean and reapply grease or anti-seize, and re-install. Refer to manual pgs. 319-320, "PT11 User Guidelines"
We continue to work on this and may update this blog in the near future as we learn more. You can download a PDF of this post HERE: PT 11-Connective Hardware Blog 2023
Ashlyn & Russell Brown
Customer comments:
When building I felt a little stickiness as I assembled my fasteners. I backed them out and applied a bit of lube. Even mold release wax should do the trick. I would guess that's what I used. A wipe with a paper towel. Tefgel is great stuff. As is moly anti seize. Any of these can be applied and cleaned off by wiping. Enough will remain. When wiping make sure the bottom of the threads has lubricant. I use paper towels and put my fingernail in the thread to wipe well. You do not need to see the lubricant for it to work. Galling is subtle but can be felt as it happens. It is a grinding crunchy feel as you turn the screw. If you feel that stop! Relieve any load on the fastener you can and back it out. As well, a tap or die can be used to clean up galled threads. With lubricant of course for cutting. Wd40 is not great here as it eventually evaporates.
Our friends at Chesapeake Light Craft will soon be heading west for the Madison WI, and Port Townsend, WA boat festivals. This is a great opportunity to save on shipping!
Save a bunch of money on shipping! Give us a call and we'll bring your big, heavy stuff with us for pickup in Madison and Port Townsend. Boat kits, big heavy items like rowing units, oars, even small orders of plywood, stuff that can be difficult (and expensive) to ship. Boat kit orders are due by August 16 so we have time to cut, pack, and stow in the rig. This offer's only good until space runs out. Call us today!
