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Fault Tolerant ESP32 Boat Monitor

My well tested ESP32 boat monitoring system ran up against the real world and the real world won. I think I am on version 50 of the software. This article goes over some of the issues I found and solved. Some would apply to anyone using an ESP32 over WiFi and some are more unique to my boat but have relevance to any system that takes real world data, makes decisions about it, and changes its behavior based on those decisions.
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DIY Boat Monitoring System

Every morning when I get up there is an email ready for me from my boat. I can look at that and see that the main pump did not go on (good), that the small pump ran for it's usual 5 seconds (also good), that the battery is charged, the shore power is on, and the 12 volt vent fan is on. (all good) These all come to me from the marina WiFi and a module based on the amazing ESP-32. In these few pages I am going to tell you not only how I built it, but I am going to give you information you need to build one yourself.
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Sending Email using ESP32-SIM800

The email send function on the SIM800 appears to be broken. This article tells how to send emails anyway.
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Low Noise Voltage Measurements with ESP32

Voltage measurements with an ESP32 are very noisy. This article shows how to make them quiet.
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Black Diamond Bosun's Chair Review

NOTE: The link for this article was broken when first published. Here is the corrected version.

The Black Diamond Bosun's chair is a well made chair produced by a well known supplier of equipment for climbing. It has a padded seat, is comfortable and adjustable. There is only one problem with it. It is not a Bosun's chair. According to Black Diamond technical support this is not a life support chair. In other words, don't let your life depend on this chair. They purposely leave off any specifications on the strength of this chair because they don't want people using it for life support.
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Ultimate Unassisted Mast Climbing (Updated 4/5/2024)

https://l-36.com/image/UltimateMastClimbing_top-2.jpg

NOTE: In reading this article today, I found that the overall process was not well explained. I added a section explaining the design and the theory behind it. I urge everyone who has an interest in unassisted mast climbing to read or reread this article.

I have tried dozens of way to climb my mast. In the process I have accumulated 7 ascenders, three rappel devices, a GriGir, and numerous carabiners. I think this climbing system is the best. It is simple to rig, quick going up, requires very little to transition from up to down, and very fast and controlled going down. I can get down in 2 1/2 minutes including rigging the rappel device.

The article starts with a short (4 1/2 minute) video that gives an overview. Start there.
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Soft Shackle Spinnaker Y-Sheet

My old friend the dual soft shackle version 1 has found a new use. It is common practice to use some kind of tail on an asymmetric spinnaker to keep the clew away from the rigging. One version is called a Y-Sheet. It connects to eye splices in the sheets and extends to some kind of connection to the clew either with a knot or a shackle. This article shows how to use a soft shackle type arrangement and not only avoid the strength loss that you would get with a knot, but basically doubles the strength of the line used for a penalty of a small increase in the length of the rope you need.
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No More StartLine on Google Play

The racing app StartLine was developed to be the best racing app available for Android. Users said it was the best thing short of Expedition. But most people found it too complicated and it never had a broad following. For those that did use it, they found success. The highest level success was a 3rd place in the Cowes race week J109 class. I personally use it along with the RaceBox in my club racing where this season I won all three series plus the TI race. Success is not just the app but the crew and the boat but I could not have done it without the app.

But the app is old and specifically it is targeted at a minimum Android SKD level of 11. This allows it to work on the older tablets I and users feel comfortable having in the marine environment. Now Google says any app that is not at SKD level 26 cannot post on the Google Play Store.
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Keeping this site working

A short article on keeping L-36.com working
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My Youtube Channel

As of 4/7/2024 My YouTube channel, @L-36, has 4,470 subscribers. The top video now has almost a half million views. To see the most popular videos, click on the link below.
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Controlling mold growth on your boat

I saw Dave reading the electrical meters yesterday and we got to talking. He told me that some boat owners are running space heaters 24/7 to control the mold in the cabin. A few years ago I ran a series of experiments to find a way to control the mold on Papoose, my 36 foot wood sloop. The mold was so bad it was literally eating the hats I hung up below. When I opened hatches, water would be dripping from the cover. The boat was wet. This is the shortened version of what I found
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Over 900 FREE Manuals

Another generous donation of 84 manuals from the J/109 Class Association brings the total number to over 900 for the L-36 manual collection. Check them out! Donations like this are very much appreciated and help keep L-36.com going.
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Turn your boat Electronic projects into Professional PC Boards

It is so easy and inexpensive to turn your pet electronic project into a professional PC Board that nobody should hesitate either due to time or money. For me the issue was how to do it. After some false starts, I found that the combination of Eagle design software (free) and PCBWay.com, was the answer. This detailed step by step overview will guide you through the process.
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Gray Marine 4-112

Just a quick reference for owners of Gray Marine engines
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ULTIMATE GUIDE TO BOAT PRESERVATION & REPAIR

An L-36.com user has put together what looks like a pretty nice boat restoration guide site. HERE is a link. Let me know what you think HERE.
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40 New Manuals Added

Thanks go out to Bill from J109 for donating 40 new manuals to the L-36 manual collection. Check them out!
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Papoose Dismasted

What can I say. My boat was run down and dismasted.
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Light List

The USCG publishes a 6 volume list of all the navigation marks, buoys, day marks, etc. that are in US waters. This list is updated each week. L-36.com now has an updated application that allows you to select an area on a map, check marks of interest in that area, and create gpx files of the waypoints as well as any routes you might want to create. You can see your marks on a map to help verify you have the right ones.
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StartLine RaceBox Video Page

Introduction videos to the StartLine RaceBox. There is an introduction of about 6 minutes, a longer video that includes a demonstration of some of the features including how to download log files over WiFi. There is also a link to the Bluetooth GPS Provider article.
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StartLine Racing on Android

NEW StartLine4 now has a Pebble app? Just search StartLine in the Pebble app store.
NEW StartLine5 will now interaface to onboard instruments over Blutooth using the
L-36.com Race Box that can be easioly built with $100 to 200 in parts depending on how fancy you want to get. Contact me for details. You don't even need to know how to solder!

Overview
StartLine is a very powerful racing app, second only to Expedition. Unlike Expedition, it is free. However, I limit the number users because along with the app comes a huge amount of support both to get the full potential out of the app but also to help users improve users race results. Users must agree to contribute to the StartLine community by providing feedback on results or actually participating in the ongoing development which may just be to ask for new features. You must be serious about racing and commit to put in the time to learn the app. It will improve your race results as it has for the other users. It is a small community but already has a podium finish in a prestigious regatta. Read this somewhat outdated manual below and let me know if you are interested in joining the StartLine team.
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Custom Marine Display

I have been looking for a display that will work in a marine environment that I can write arbitrary text to. I signed up for a Earl Backpack Tablet but it looks like it is vapor ware so I got my $300 back. I next considered using the TackTick Remote as the manual says that it can display 6 custom sentences. I bought it but could not get it to work. After a month of trying to get an answer Raymarine said that it would not work due to a software change and that their solution was to change the manual so that it would no longer say it works. Sucks. My next attempt was to look for a company that made a NMEA-0183 display and see if it could display custom $P nmea sentences...
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Knife Review -- one year later

It has been a year since I wrote the knives on a boat review. It was really a review mostly of every day carny or EDC knives with one specifically marine knife with a marlin spike. I have lived with these knives and find my favorites to be a little different than my first impressions. I still like all these knives very much but the question is, which ones do I end up using and what do I use them for. For this review, I have added short 15 second videos of the knives opening and closing so you can get a better picture of how they work. I also added a discussion on two knives I bought recently. One I returned the same day and the other I am not really sure what I am going to do with but it is so nice I just had to get it. It is a knife I have coveted since the first time I saw someone with one.
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Unassisted Mast Climbing Update

In the article on Unassisted Mast Climbing I prefer the modified method but mention that the GriGri method is easier to use. There are two things I did not like about the GriGri method 1) It requires re-rigging the setup at the top of the mast. That is really a most unpleasant experience. 2) The descent, while quick and easy, it jerky and can be frightening and if you panic, can be really scary. I have developed a new method for the re-rigging and descent that solves the second complaint but you still need to do the re-rigging. This article presents that technique and reviews the GriGri method.
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Oh the horors of having tape pull up the paint below

Seemed like a simple enough project to paint the deck on my boat. Add some non-skid and repair several years of little cracks where the old non-skid was coming off. It turned into the project from hell when the masking tape pulled off the paint below. In spots it did not pull anything off. In spots it pulled off my fresh paint. In other spots it pulled off 10 years of paint leaving rather deep ridges. In one spot it pulled off all the paint, 60 years worth, all the way to the base cloth. This was a low stick tape. It was not as low stick as the tape I once used so I started looking for more of that tape. I could not find it but I did find a list of tapes and how sticky they are. This is not very easy to find so I thought I would share the results of the several hours I spent online finding this information.
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GoPro Fogging

The promise of videos of my sailing was too good to pass up so I bought a GoPro Hero 2 shortly after they came out. I did get some good videos but all too often the images that came back would be fogged up. It got to the point that I just didn't want to bother to put the camera on the boat because I knew the videos would be fogged. I tried many things to prevent this but nothing worked until this last time.
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My GoPro will not Turn ON

My Gopro Hero 2 would not turn on. I had done nothing to it since last using it except letting it sit. I knew the battery was charged and the SD card was good because I have two GoPros. The battery worked in the other camera as did the SD card. Of course, if your GoPro does not turn on, check the battery. The first test is to remove the battery and SD card and plug in a charger using the USB cable. The red light on the front blinked and when I pressed the power switch the red light went out and the unit did not turn on. The red light flashing proved that the USB cable was good and the fact that it did not turn on proved I had a serious problem.

The solution is to update the firmware using GoPro Studio. But you must have the camera on to do this.
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Racing with a Whisker Pole

Most sailors have whisker poles to hold a jib out to weather. Not that many use them in racing as a spinnaker is the preferred sail for racing downwind. But not everyone wants to use a spinnaker and some of us race in classes that do not allow spinnakers. Over the years we on Papoose have tried to prefect using a whisker pole while racing.

What I am about to discuss conflicts with the instructions you will find for using a whisker pole. The conventional methods assume you are not racing and are not helpful if you are. Cursers can furl the jib, set the pole, and then unfurl the jib to the pole. To remove the pole, they can furl the jib back up. A racer would not want to do this even if they could but there is no reason a cruiser has to either if you know some of the tricks discussed in this article.
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Race Committee Timer

Race Committee Timer, RCTimer, is an Android application designed for race committees to do starts for sailing regattas. The timer can be set to a count down time, for example 5 minutes. It can also be set to a specific start time, for example 12:30. A sequence can be set so that multiple fleets can be timed in rotation, for example a start every 15 minutes. The timer can be started or stopped and minutes can be added. There is a reference page with signal flags and a lock button. The latest feature is that the app will now talk or sound a horn blast. Sounds can be programmed to occur at any count down time and anything can be said. A simple text file defines what is said or when the horns are sounded. The app is free. A version without sound is on the Google Play store under RCTimer.
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Hybrid Soft Halyard Shackle

Yet another way to make a soft halyard shackle out of Amsteel. This is one that I am using on my boat. The advantage is that the hybrid knot gives approximately full line strength but only extends a couple of inches so that the short splice will not end up making the line that goes into the sheaves fatter. This prevents extra wear in thinner halyard sheaves. The knot provides the locking action which removes most of the load from the splice. The short bury distributes the load enough so that not all of the load in on the knot. The result has been tested to near full line strength. This knot is one of just a few that do not slip in Amsteel. The knot is strong and the splice prevents slippage.
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Block Mechanical Advantage

This is the first part of a two part tutorial on mechanical systems made from blocks and line. I will explore the mechanical advantage of various systems, and shows the general principles on how to set these systems up, including how to thread the line through the blocks, or reeve them. It will go from 1:1 to 6:1 with simple systems and up to 24:1 with cascaded systems. The second part will explore some more unusual systems.
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High Strength Soft Shackle

Recient work by Brion Toss, Evans Starzinger, and myself has led to the development of a high strength soft shackle that Evens has tested to 230% of line strength. The secret to this added strength in primarily an increase in the strength of the knot, the weak point in conventional soft shackles. I should point out that Evans testing shows conventional soft shackles, with diamond knots, test at 170% of line strength, considerable above the "higher than line strength" number I have been using. While these two statements are consistant, the more percise number is considerably higher and higher than the testing I had done at NE Rope.
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The First Bend

This bend has been tested. Sometimes it slips, sometimes it breaks. Either way it is stronger than a triple fisherman's. Amsteel is very slippery. It is difficult to test a knot that slips and even harder when it slips sometimes. If you pull and let it sit after it starts to slip, it recovers and ends up being strong, something above 40% of line strength by some tests. There are other knots that almost never slip, see the Last Bend but it is ugly and not near as simple or easy to tie as this knot. The standard for tying Amsteel or Dyneema together is the triple fisherman's knot. This knot slips less that a triple fisherman's so it is a step forward slipping or not. When it doesn't slip, it is stronger than the Last Bend. I present it here for your consideration.

Both the First Knot and the Last Bend can slip at about 35% of line strength. When they don't slip, they are about 40% of line strength with the First Knot just a little above this and the Last Bend below this. There is another variation that slips at about 40% that I will show here as well. You can untie the First Knot, but not the variation. This knot can also be untied even after being loaded up near breaking. Just put a spike through the center to loosen it up and remove the tails from the knot center. The rest is easy.

I am calling this knot the First Bend because by the time I was done testing dozens of variations on knots and never wanted to hear the word bend again, I called the final knot the Last Bend. It did well but upon considering this knot, the first one I considered, I came to appreciate it more. In fact, I am declaring it the winner of my search for the best bend for Dyneema. That said, the variation is stronger.
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Automatic GPX File Marker and Route Generator

The set of tools that will generate a GPX file for your GPS has been recently fixed and I thought it time to make people aware of this valuable tool again. With two map clicks you can get a list of all the marks in that area, select the ones you are interested in, edit their names, and download a GPX file to your computer. These are USCG generated locations from the many volumes for all US territories. The search through all the volumes is done automatically. In just a couple of minutes, you can do what might take an hour to do previously. Please enjoy these tools.
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How to Fly a Spinnaker

This 8 page tutorial covers all the terms, positions, and tasks of flying a symmetric spinnaker using the end for end gybe technique.

I have had Papoose for 23 years and never used a spinnaker on her. Last two seasons we won the local beer can series using a free flying jib downwind sometimes along with our normal jib. But we always had to play catch up to the boats that used spinnakers. I decided to learn to fly a spinnaker so we could move to the next level.

I joined the crew of a very successful Tarten-10 for the winter series. I used a GoPro camera to document as much as I could. This training series of articles is the result.

Lazy Lightning (the T-10) uses end for end gybes which are said to be appropriate for boats up to 35 feet. It is much simpler to rig and execute than a dip pole gybe so is the preferred method for boats such as mine which fly smaller spinnakers.
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Tide Page

This new tide page will show tide chart, table, and hourly tide or current. Search for a tide station by entering part of the name. Select from the list of possible stations. There is a list box that shows nearby stations if you want to switch locations. A map shows where the station is registered.
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7-Day Tide and Current Forecast

Improved 2/27/2013 - Graph now goes midnight to midnight. Added title to each section.

Tables and graphs for selected tide or current station for the week ahead.
Table shows high and low times for tide, slack and peak for current. Also shows sun and moon events. Graph is as shown below. The final table shows the hourly values.

Sorry tide depth graphs only, please select another station.

Sorry tide depth graphs only, please select another station.

Input GPX or CSV Files
Add any number of additional waypoints
Edit any name, location, or symbol
View location of waypoints on map
Download as either GPX or CSV

The file at the left is an example of the map view of a file about to be edited.

This tool can be used to convert any Garmin gpx file to a StartLine csv file. In addition, you can use this to read your gpx files into Excel or Word processor for analysis, viewing, or editing.
GPX -> EDIT -> CSV
GPX -> EDIT -> GPX
CSV -> EDIT -> CSV
CSV -> EDIT -> GPX

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Weather Page Updates

It has been about a year since I reported on the L-36.com Marine Weather page. There have been many improvements to the page in that time that I want to share. The page has been well received and has hundreds of users. I thought it would be useful to point out some of the improvements for those of you who have not tried it recently.
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8:1 and 20:1 Cascade Vang Systems (and link to 16 more vang systems)

A 8:1 Vang system that is cheaper than using two fiddle blocks, lighter, and stronger. What is not to like? You just run the control line back to the cockpit where you put a cam cleat. You will likely need a turning block on deck but then you have the vang where you want it when it needs to be released quickly before you round up.

The second vang system shown is the 20:1 vang on Papoose. This is a unique system with some advantages that are discussed.

This page also has a link to 16 standard variations on vang systems.
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GPS GPX Batch Waypoint and Route Creator

Entering routes into a GPS when you have a number of them to enter is easy with this bulk route editor. Import waypoints from a gpx file or enter directly into this page, then simply write out the routes all at once and create a custom gpx file with the waypoints and routes ready for export to your gps device or chart program.

As an added bonus, Latitude and Longitude can be entered in almost any format, even both in one input box, for ease of copy and paste entry.
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Latitude Longitude Converter

Convert between different latitude and longitude formats. Then copy and past the converted format into other programs. This program will take most any format as input and outputs the result in five different popular formats.
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Gross Fine Mainblock Reeving

mainsheet_systems/mainsheet_lazy_lightning.png

Two ways of reeving the mainsheet in this gross fine mainsheet system are shown. The more obvious way to do it is shown on the right. The problem is that the lines hit each other, the fine control blocks hit the main sheet, and in general it has problems. The other way rotates the main dual block by 90 degrees and has no such interference issues. It also opens up a large space for the fine tackle so that it does not rub on the mainsheet.
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Soft Line Shackle on a Block

image/soft_line_shackle_2_soft_line_shackle_0.jpg

Using a line shackle and stopper loop you can in some cases eliminate hard shackles even from places that would be impossible to do with normal soft shackles. The stopper loop can be "tied" to the clevis pin and the soft shackle integrated into the line for a clean light installation.

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A Better Soft Shackle

My "Better Soft Shackle" has become the standard in soft shackle design along with the stronger soft shackle. I invented this version several yeas ago and was co inventor of the stronger soft shackle along with the late Brion Toss and Evans Starzinger. Of the two versions, I prefer this one. It is easier to tie and easier to use. If I want a stronger shackle, I start with stronger line. For example, the stronger soft shackle is 35% stronger but going up one line size gains 60% in strength. All things considered, I believe this is the superior version.

The original soft shackle is rather difficult to open and to milk closed. With age, it becomes increasingly difficult. The alternative Kohlhoff style is easy to use, but it sacrifices some security. This version incorporates the best properties of both of these versions. The eye is easy to open but can only be opened just enough to fit the stopper knot through it. Almost any slight force will close it quickly.

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Try the L-36 Weather and Tide Page Now!

Examples of valid inputs: "San Francisco, CA" "Golden Gate" "Balboa" "Cow Island" "94301"
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User comments about the Weather and Tide Page from Forums and emails

Your site is now my primary weather information. While I really like the way NOAA provides info at their sites, yours is more comprehensive and easier to use
Your website is approaching world class. Really Great Job.
Keep up the great work, The 4 people I sent the link to loved it.....
Been playing with it off and on all week. It's already replaced my usual weather info site. Excellent work.
I just wanted to thank you for the terrific weather page. It is my daily go-to page for marine weather. I sail a pair of boats on SF Bay and out of Santa Cruz, and your web site is really extremely handy. It is far better than the "commercial" sites, which is a real tribute given their budgets and what yours probably is.

Soft Shackles

This is the introduction to a series of 6 pages that deal with soft shackles. Step by Step instructions on How to make a soft shackle, some Variations, and some detail on the diamond stopper knot, . . These are incredibly strong. I show how they are used, below. Nothing is useful until it has been tested , so check that page out. There is even a Calculator so you can make them come out the length you want. Enjoy the series.

To the left is a picture of the soft shackle on the jib clew. The addition of the Velcro keeps the diamond knot in the center of the clew ring where it will stay out of the way of the rigging. These shackles are very strong. I did some testing and it is clear that the sheet with the eye and the soft shackle is much stronger than the sheet with the bowline. In my testing, the line broke at the bowline. You can follow the links above and see how to make them, as well as the testing that I did. I did the testing at 2/3 scale which is a little less than 1/2 the strength. The test at the bottom of the page was done to distruction of a link line made of the same Amsteel thus showing that a soft shackle is stronger than the line it is made from. On the rest of this page, I show how to use a soft shackle.
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Double Soft Shackle

This double ended soft shackle is the 4th generation of a design that can attach to a pair of eye spliced jib sheets to the clew of a sail very quickly. It is also the 5th version of this generation as improvements were made to make the shackle stronger. In use, the shackle is secure around the jib sheet prior to being "clipped" to the clew. This version is easy to make and has the advantage of a non-constricting hold on the jib sheets. There are links to the previous versions at the bottom of this page

The Shackle

This soft shackle in integral to the main halyard. It is made from a single line with a combination of knots with a finishing splice. I have tested it to over 1000 pounds using 3/16 Amsteel without slip. While I have not tested it to destruction it is very likely that the shackle is stronger than the line so that the failure would be outside of the shackle area. I base that on the fact that the shackle area is made of either 2 or 4 lines so any loss due to the knots is unlikely to bring the strength below line strength. Of course, a halyard is typically not loaded that high as the application is mainly stretch limited. That said, be sure to do your own testing before using this in any critical application.
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We were happy on Papoose to have won our class but sad that one of our fleet was so badly damaged. Eventide was damaged just before the start by a boat from another class.
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Eventide T-Boned in MM Regatta

"Eventide was badly damaged at the start of the 2011 Master Mariners. She is safe in her slip in Berkeley and I am making a plan and exploring options for repairs and replacement rigs. I am extremely grateful for the support of the L-36 and Master Mariners community. Damage appears to be limited to her planking and obviously her rig. I will keep the L-36 community updated as to her status. Any previous experience or advice on repairing a large section of an L-36's hull is welcome. I can be emailed directly at gregmilano (at) hotmail (dot) com. Thank you for all of your support."
Greg Milano, Eventide

My harbor early one morning

Soft Halyard or Line Shackle

I am calling this a soft halyard or line shackle as it is certainly not confined to use only on halyards. It is a combined splice-shackle and is similar to a soft shackle where the opening eye is on the line and the knot is on a second piece. It is much faster to use than a soft shackle. In applications where the line is 12 strand spectra such as Amsteel, this is a perfect fit. I have tested it to destruction and the failure was similar to other tests of soft shackles which broke at the diamond knot. Based on all these tests, my conclusion is that it is 80-90% as strong as the line. I must add, the force I put on my 1/8 inch Amsteel using a hydraulic jack was huge, many times the force I got using a Barient 22 winch even with 1/8 inch line. In other words, this is a strong, easy to use shackle is integrated into a line such as a halyard. The line in all these photographs is 3/16 Amsteel Blue.

Two TP-52s

Knot Meter Calibration

In many area calibrating a Knot Meter is a simple matter of setting it to read what the GPS reads. But if your boat is in areas where there are tides, local current can make this method inaccurate. The following method can be used to calibrate a knot meter even if there are very strong currents.
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Samba Pa Ti and GG Bridge

Over 200 Marine Manuals

Listed Alphabetically
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Boat Dimensions

BOAT	I	J	P	E
Lapworth 36	40.5	13.5	35.5	17.5

Click Here for other boat types

Sail Area Calculations
Mainsail = (P x E) / 2 = 311 sq ft
155% Genoa = (( J x I ) / 2) x 1.65 = 451 sq ft
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Two Melgeis 32's on split tacks heading to the windward mark
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