ELECTRO-CHEMICAL DAMAGE IN WOODEN BOATS UPDATE A Special Post By Chris McMullen
Recently I received a note from Chris where he questioned if the story we posted last year on ww about electro-chemical damage to wood was a little too long & were people reading it. Well I can tell you that the post is the single most visited story on ww, ever, & gets read by people all over the world. Its frequently referred to on the hugely popular WoodenBoat Forum in the USA. The link below takes you to the original story.
For the impatient ones out there 🙂 Chris has done a ‘Readers Digest’ version & refers to a vessel that recently featured on ww.
I encourage all of you to read today’s story & if you own a classic wooden boat – read both versions – the problem is the biggest risk to the life of our classic boats.
In Chris’s words: “I received the above disturbing images of another woody being destroyed by an owner who I believe is unintentionally loving his boat to death.
The use of anodes and bonding on a wooden boat is fatal. The cathode or protected metal makes hydrogen gas and this combined with saltwater makes Sodium Hydroxide (Caustic Soda). This chemical is used to pulp wood in the paper making industry. Not on my boat thank you! I say again, there is no reason to use anodes and bonding on any boat. The only exception, steel hulls require anodes. If copper or bronze are being corroded it is due to a positive DC leak and Zinc anodes will not help. Find the electrical leak is the cure. If there is brass or manganese bronze underwater it will corrode due to the zinc in the alloy. Anodes will possibly stop the corrosion but at the expense of wood damage. A better plan is to replace the brass with proper marine bronze.
Bronze and copper should last indefinitely in the sea. To prove that statement, I ask you to look at the Roman coins and artifacts salvaged from ships wrecked in the fourteenth century. There was no anodic protection and the metal is well preserved. So what is the difference to the copper and bronze on your boat? There is absolutely no difference so why waste your money buying anodes that will in time destroy your wooden boat.
Three or four bottles of wine will cost the same as anodes and will make you and your boat happier.”
Note: ww is read all around the world, if there is water & boats, there are people reading ww. So a little about the man for non kiwi’s – Chris is one of NZ’s most respected boat builders (retired) and at one time was the Lloyds (Honorary) Wood Boat Surveyor in Auckland. Chris’s (the original company) ‘McMullen & Wing’ built and repaired wood, steel and marine aluminium vessels. They built the first welded aluminum vessels in NZ. Chris is the current holder of the Classic Yacht Association of New Zealand ‘Outstanding Achievement Trophy’ for services to classic boating.
14-05-2016 Photo Update
Gavin Gault sent in the below photos of a Nova skeg floor that he believes were probably damaged due to engine – anode bonding failure. Pretty graphic !!
10-07-2016 Reply from Chris McMullen
“Wow. Thank you Gavin Gault for sharing your very graphic images. Very sad, small consolation but yours will not be the only wooden boat affected by this scourge. Maybe, at last some of the Flat Earth Society will start to believe what I have been saying. The worst detractors are some in the Marine Industry who have been preaching the Anode, Bonding party line for years. Now there is no where to run for cover, they continue to conjure up excuses and it seems, refuse to accept a simple scientific fact. “If you have a positive and negative electrode in salt water, the negative cathode or protected metal makes hydrogen gas and this combined with salt water makes Sodium hydroxide.” This chemical is also known as caustic soda and removes paint and destroys wood. There is no doubt about this fact. You do require a power source and bonded dissimilar metals ( zinc and copper) provide sufficient current to do the damage, but slowly. If there is a negative DC leak (to the sea)on a bonded boat the process is accelerated. If there is a positive leak any metal becomes an anode and will waste away. It is important to isolate the DC power from contact with the sea. Again bonding is just asking for trouble. Please remove Anodes and Bonding from your wooden boat now! Chris McMullen”
06-09-2106 In case you were not to sure what to look out for – the below photo should be a wake-up call to a few woodys 😉
Alan Houghton,Baden Pascoe, Chris McMullen, Rod Marler
SPECIAL ANNOUNCEMENT – CYA Outstanding Achievement Trophy
Last night (Dec 5th 2015) at the 2015 CYA Patio Bay weekend BBQ / Xmas party CYA member Chris McMullen was presented with the CYA Outstanding Achievement Trophy for services to classic boating. The trophy has only been presented once before (Haydon Afford).
Now Chris is a regular on ww & has sent most of his life in & around wooden boats. As a founding partner in McMullen & Wing boatbuilders there would not be a medium that Chris has not applied his skills to – wood, steel, alloy & the f word (fiberglass), the great thing is that thru-out his career he has remained true to his passion for wood. Even today Chris is at the forefront of trying to raise awareness & educate classic wooden boat owners on the issue of electrochemical damage to wood.
There is no other living, New Zealand wooden boat enthusiast more deserving of this award & I was proud to stand alongside Chis when he received the award.
On the weekend CYA cruise to the Riverhead Hotel we were joined by (to me) a new classic on the CYA scene, Venture. Keen to learn more about her & what lies underneath the ‘addition’.
Neil Lineham has advised Venture was built in 1961 by Morrie Palmer and apprentice Chris McMullen for Stuart and Peter Opperman. The boat built after her (1963) was Neil’s fathers boat Oranoa, built in the old police station at Clarance St Devonport. Oranoa is still owned by the Lineham family.
04-11-2015 Input from owner Jeff Norris (edited by Alan H)
Venture was built by M. G. Palmer at Devonport launched in 1964 the first owner was a Mr Hudsmith he owned her for 30 years . The design for the 36′ Venture was ‘influenced by’ Colin Wilde. She is powered by 86hp 6cyl Ford Trader she used to have a 30hp Perkins wing motor it was removed by the owner before Jeff. Jeff has owned venture for 15years and is in the process off doing a tidy up and a repaint off the top sides . They are going to glass the hull next year and maybe a re-power as the trader is getting very old but still runs perfectly, Morrie told Jeff , there is a sister to Venture but it is a bridgedecker , Morrie built Venture for himself but had to sell her before she was finished . Venture was a very good game boat in her day but now she is just a cruiser.
02-05-2016 Photos of Venture at the CYA Raft-up at Salthouse Boat yard (Alan H/Ken R)
22-10-2020 UPDATE – WW has been advised that the 36’ Venture suffered some damage in March this year when she was pulled out for antifouling. As a result she was leaking about 10litres a day and has been out off the water for about a month now. Owner Jeff Norris commented that she is a easy fix to make her dry again, e.g. the hull needs a really good rub back and coat of paint, some corking and scrape back.
Jeff has decided to sell her as is, and at a price of around $15k, could be a good entry point to classic wooden boating. Move quick – she goes on trademe soon.
And just in, a trip report from CYA chairman Rod Marler, currently in New York. Rod did a circumnavigation of Manhattan on this fine ship yesterday. I would say she is a replica but her heart is in the right place 😉
Chris McMullen & his 1898 reproduction Herrreshoff steam boat
One of Chris’s experiments
Otira- 1902 Logan Bros
Otira- 1902 Logan Bros
And of a few photos of one of the prettiest boats on the Waitemata – Wirihana, the 1933 Colin Wild launch.
A Visit to Chris McMullen’s Boat Shed
Yesterday was a biggie on the wooden boating front – Barbara Cooke & myself organized for the Classic Yacht Association a visit to Chris McMullen’s workshop & boat shed. I have posted photos of the shed & its contents on ww before & ww has published several of Chris’s posts on the topic of electrochemical damage to wooden boats – but it was special for the members to meet the man himself & hear him speak on his past, his current passions / projects & future plans. The reproduction 1898 Herreshoff steam launch project just has to be one of the best kiwi ‘can-do’ tales around. The day she hits the water will be a very special occasion, I just hope I’m around to see it 😉
Today two things stood out for me: 1. The turn-out of two wooden boating icons – John Salthouse & Max Carter 2. The healthy number of sub 35 year old guys with a new found passion for classic wooden boats in attendance
If your a CYA member & you didn’t make the effort to come to the event – more fool you – as one of your most respected members said to me “today was a privilege, Chris is a one of a kind, his practical knowledge on boat building and engineering is unique”.
In my time as CYA launch captain one of my personal goals was to help deliver up events & access to people & ‘cool stuff’ that people would not normally have access to without being CYA members – from the comments & the smiles as people where departing today, Barb & I got it right today 🙂
To read / view more on Chris, his boats & the topic of electrochemical damage to wooden boats just enter – Chis McMullen – in the ww search box 😉
Electrochemical Damage To Wood – the marine version of ‘leaky homes’
Story & photos by Chris McMullen. Edited by Alan H
NOTE: The photo above is the residue left from a heart kauri floor. The keel bolt had been bonded for ten years. Impossible to affect a proper repair as the bolt went through the deadwood.
Today’s post appears on WW for three primary reasons:-
#1 the author Chris McMullen is someone I & most intelligent, thinking boaties respect.
#2 waitematawoodys is all about the study & appreciation of classic kiwi wooden boats – if people do not wake up, there wont be any to appreciate.
#3 this information needs to be stored somewhere like waitematawoodys so when people are searching the topic of electrochemical damage in wooden boats, they will find this & be able to make their own decision based on sound, robust debate like the below.
Most people are aware that Chris is one of NZ’s most respected boat builders and at one time was the Lloyds (Honorary) Wood Boat Surveyor in Auckland. Chris’s (The original Co) “McMullen & Wing” built and repaired wood, steel and marine aluminium vessels. They built the first welded aluminium vessels in NZ.
Public opinion back then was, “They were mad” and the hulls would fiz and corrode in salt water. Not so, and now aluminium is used for not only yachts but all types of commercial vessels.
Chris is also the custodian of the magnificent classic Colin Wild launch ‘Wirihana’.
Chris is constantly asked for advice on kauri vessels with wood degradation problems. His view is somewhat different to many marine industry technicians in NZ but backed up by Yacht Surveyors in the USA and the UK.
If you don’t have time now to read this post today, please bookmark it, as I guarantee it will at the least have you doing a double take.
Update 06-06-2015 – if you are time poor scroll to the bottom, new info & photos added
I’ll let Chris tell the story. Alan H
Chris McMullen – I am absolutely convinced that any wet wooden (caulked) vessel is doomed to a slow death if dissimilar metals or zinc anodes are fitted and bonded by wire to underwater metal. I do not reject the theory of cathodic protection; in fact I use it and zinc anodes on my steel floating dock. The problem is the wet wood component. There is a voltage between any two connected (bonded) dissimilar metals and the wet wood completes the circuit. Any voltage in the wood (from any source) breaks down the lignin in the wood round the cathode (protected metal) and that is the issue.
The white corrosion byproduct formed, Sodium hydroxide, is used for pulping of wood in the paper making industry! Want this on your wooden boat? Yuk!
Included below are some links to technical papers written by wood chemists rather than by metallurgists. These articles are not new but quite convincing and are parallel to my thinking and experience.
It seems however that people don’t like reading technical stuff. And it’s (I guess) easier to read and believe what is written in a local boating publication.
I decided to do an experiment to prove my point.
I used a length of 6”x 1” pine. I bolted to it an old zinc anode and about a metre away bolted two bronze objects. I connected one to the anode with a copper strip and the other is close by but not connected to the anode.
I hung these on a rope in the water of the Tamaki River (salt) off my floating dock.
After six months, I pulled the test rig out and cleaned off the considerable marine growth.
I removed the bronze objects. Under the one connected to the anode was a black stain and the bolt fell out of the hole. The other, the bolt had to be punched out and the timber was clear bar some copper residue.
I photographed the test & also took the voltage readings between the metals and also the metals potential against a silver-silver chloride reference. (click photos to enlarge)
The minor damage done to my test piece is the result of only six months submersion. I will put it back and check in another six months.
It is however, quite obvious to me some thing is wrong and in time the wood will deteriorate further. If this is due to a voltage (less than half a volt) well, you can imagine the damage coursed by electrical stray current, and that is likely on old boats. My test rig is very basic and not influenced by other factors.
Sure, the wood may be less effected if painted and if the bronze was insulated by bedding compound. The damage can take years but our kauri boats should last indefinitely if we don’t do things that destroy them. Someone is bound to say I have over sized the anode on my test and thus the timber damage. I know that is the case but I had to accelerate the process.
On a boat it is almost impossible to size an anode correctly due to wasting and wiring faults in inaccessible areas of the bilge.
The point I am trying to make is:
Eliminate any current flow in the wet wood.
If you bond metals underwater you are inviting problems.
Further, a stray leak from the ships battery will do far more damage in less time. I believe most metal corrosion problems originate from this source. Cathodic protection will do nothing in this case.
Again, bonding will encourage a circuit. Remove the bonding and you have no circuit.
Want to check your electrical system for stray voltage in your wet hull?
Connect a voltage meter between the positive on your battery and any bolt or fastening in your hull. You may get a surprise. It may be 12 volts but high resistance so you can’t light a bulb but enough to cause corrosion.
If you have bonded underwater metal, the surprise maybe an expensive. For a start, try tightening the lag screws fastening the stuffing gland to the shaft log. If you don’t, a surveyor will, if you ever want to sell your ship.
History
In Yachting World Magazine March 1957 Mr. MG Duff wrote a convincing article headed “Stern Gear Corrosion” (cathodic protection for underwater metal fittings on wood yachts”.) In the article he never mentions wood degradation! He did not know until the problem showed up years later, see below.
The subject article date (1957), ties in with my memory of Jack Brook (head of the old D.S.I.R) yes, Robert’s father, and Alan Odell (Professor of Chemistry) fitting an Anode on the Tobin Bronze(H/T Brass) shaft of Alan’s Logan yacht the “Mahaki”.
I was only a kid who happened to be at Devonport Yacht Club with the Odell’s that week end. I remember a crowd of onlookers thinking this was black magic.
I believe this resulted from the Duff article. Later Jack Brook had the DSIR print a pamphlet on the subject. Sadly, (like Mr Duff) these academics never thought about wood damage.
Now using anodes did not catch on here until the late1970’s when a local business man saw it as an easy way to print money. He, like the Duff article was very convincing and I am sure well meaning. Some wood boat owners now refer to him as Dr Death! (I never coined the name)
Since then almost every marine electrician has got in on the bonding scheme. It was a new subject for books and magazines, now some misinformed boat owners are pushing it too.
On a hard stand a boat without an anode stands out and in many eyes shows an uncaring owner and will draw criticism. This is mistaken thinking and sadly is self perpetuating.
Please consider, “Logan, Bailey and Wild never used cathodic protection. They had knife switches and crude electrical systems but no bonding! Their boats lasted 60 years plus. ” Why should we use anodes?
As an apprentice wooden boatbuilder, we were told at night school, I quote “ “Never use dissimilar metals underwater” and further ” never use brass”. These days the advocates of bonding use zinc underwater! What could not be more dissimilar or further apart on the Galvanic scale?.
In the 1960’s and prior to that, boat builders used bronze and copper only. There were no stainless shafts available ex stock in New Zealand.
Despite working on all sorts of boats, I never saw the timber degradation I have sighted in recent times. Sad, as we no longer have the kauri or people with the skills to affect these sometimes major repairs.
The boating public and boating industry technician’s have been mislead by a situation rather like “The Leaky Homes”, just because everyone is doing it, does not mean that it is right.
This problem was aired in Wooden Boat Magazine (30 years ago) Also in Classic Yacht Magazine. I sent some information to New Zealand Boating magazine. They showed no interest. Their advertisers sell anodes! Big business!
Further, the NZ Marine industry is partly to blame. Locally made strut bolts were made from tobin bronze! tobin bronze (these days) is brass and in my opinion unsuitable underwater. Their “Through Hulls” were made of gunmetal that although a bronze, is in my opinion a very poor choice of material. Use aluminium bronze or silicon bronze or reinforced plastic.
Cheap propellers are made of manganese bronze. Again a poor choice (these days) and little better than brass! Use aluminium bronze for propellers.
Bronze gate valves have brass spindles. Use reinforced plastic valves.
A lot of confusion comes from reading old books. (See L Francis Herreshoff “Common Sense of Yacht Design”) He recommended tobin bronze (Trade Name) and manganese bronze.
These are now generic terms. Both materials were (possibly) once good marine metals but over the years the makeup of these alloys or the way they are cast has changed and as a result I believe their resistance to dezincification has been compromised. This is evidenced by. See https://www.flickr.com/photos/109707376@N06/11134934714/
This manganese bronze propeller (Mizen Head Ireland) had been underwater 100 years! I checked it out some years ago. The bronze blades with the “Stones” trademark look perfect. The Stones Co. built ships propellers all from manganese bronze! Yes, the iron hub was an anode and (possibly) protected the bronze. A perfect example of cathodic protection! Note.There was no WET wood involved.
I talked to the new owner of Chatfield Engineering. He tells me they are now using silicon bronze for strut bolts. I say “Not before time”!
Sopac Marine Ltd is importing “Groco” silicon bronze hull hardware from the USA. They also stock aluminium bronze plumbing fittings that will last forever.
Support the local manufacturers? Unless they tidy up their act, they do not deserve your support.
Please remember bonding poor quality underwater metals does not guarantee their security. Read about “Random Harvest” (Link below)
Boats are supposed to be fun but you really have to be an expert to keep your ship afloat.
It all comes down to attention to detail. Use the right marine materials, be sure your wiring is done properly and your boat will not suffer from metal corrosion. You certainly won’t need bonding or anodes.
Sadly, for most it is too late. Cut the bonding & remove the anode but the caustic soda corrosion byproduct previously formed will remain and continue to soften the timber. Remove the effected timber round the cathodically protected metal or live with the problem caused by LOVING YOUR BOAT TO DEATH.
Some hints to eliminate DC Voltage Leaks in Boats.
1. Insulate the negative connection from the frame, on alternators, generators and anchor windless motors.
2. Use two pole senders on the engine alarms.
3. Install a solenoid on the starter motor negative so it is only connected as the engine is started.
4. Battery switch’s can leak. Have a second switch on the negative.
5. Be sure your bilge pump is wired correctly and in good order.
6. Use an insulated gearbox to shaft coupling.
7. A Furuno depth sounder is two wire but the bronze housing (like an alternator) connected to the negative! Sleeve it with plastic so there is no connection to the wood. Leave it, and it is unintentionally bonded and you have a circuit.
8. If you have shore power, use an isolating transformer.
9. If you still must bond for safety purposes? Well, accept the fact you have made a circuit and face the consequences, maybe you should not have a caulked wet wooden boat!
Why go to all this trouble?
The negative wiring in the ship can act as bonding wires if the appliance on the end has been designed for automotive use (chassis metal is usually the negative ground on a vehicle.) and touches damp salty wood. Say, for example, you have a negative leak in the autopilot drive that is coupled to the rudder that carries an anode. You once again have made that dreaded circuit and the wood round the rudder gland will suffer.
On a metal boat all the above is mandatory.
Put up with some minor corrosion.
It is easier, to replace a metal fitting than the wooden hull structure. Further it is pointless putting an anode on a aluminium bronze rudder (as is often seen) Of course the anode will erode. The bronze is a marine metal and does not require cathodic protection. If it has a stainless Shaft well that is dissimilar metal underwater. If it corrodes, change the shaft to bronze is the best advice.
If you are worried about your stainless propeller shaft, have a cast iron (nut type) sacrificial anode made. It should only have contact with the shaft not the bronze.
I write this (as a boatbuilder and certainly not as an expert) It is the result of my experience and research into a problem, I first noticed thirty years ago but seems more prevalent in recent times.
I share my observations, for the benefit of classic boat owners to help assure the long life of their vessels.
There is nothing in this for me.
For those interested I would encourage you to click on these links & read carefully.
If nothing else page 4. Written by a Wood Chemist in the USA.
Nothing has changed, except I gave up, trying to convince people. It is no fun swimming against the tide.
See below on how to make paper.
Soda Pulp
Soda pulp is the original chemical pulp and is produced by cooking chips of (usually) deciduous woods in a solution of caustic soda under pressure. This leaves a relatively pure cellulose pulp which is then washed and bleached. Soda pulp produces relatively soft, bulky papers (as a filler with other pulps) used in books, magazines and envelopes. Caustic soda dissolves most of the lignin in wood while having little effect on the cellulose. Cooking liquor is recovered during the washing process.
It Is Not Just A Wooden Boat Thing
The photos below show a carbon fibre boat and a fibreglass yacht bonded and with electrical issues. The point here is that all boats can have electrical issues. On these boats it showed up. On a wooden boat the damage is invisible until it is too late.
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06-06-2015 A Short & Hard Hitting Update From Chris – Read It, Its Pretty Simple Really!! Alan H
Less zinc, more zinc, over zincing are terms used by those who have recommended bonding to their clients and when things go wrong and they will. They have to have an excuse.
Please consider the following.
Sodium hydroxide or caustic soda is the chemical that damages the wood. This chemical is used for pulping wood and used in the paper industry
You will find the requirements are a positive and a negative electrode of say carbon, a container of brine or salt water and a power source i.e. a battery charger or a battery.
Now on a bonded boat you have a zinc anode that is positive and the protected metal (the cathode) is negative. You have the sea water electrolyte and if you have any stray current (and that is likely) you have the power source.
You don’t actually require the power source as there is a natural battery with a continual current flow from the electro-positive zinc anode towards the protected metal or electro-negative cathode.
So in effect you have a sodium hydroxide manufacturing plant (factory) incorporated in your bonded boat. Now this plant runs 365 days per year or until you sacrifice the anode.
If there is an electrical leak on the boat, well the plant ups it production.
Now the sodium hydroxide coats the protected metal and the old wet wood assures an all over electrical connection.
So it is the sodium hydroxide that causes the degradation of the wood surrounding metal on all bonded wooden boats.
Unfortunately, there has to be a current flow between any connected dissimilar metals and zinc is way apart from copper and bronze on the galvanic scale.
So it is obvious you should not use zinc anodes and bonding on a wooden boat.
Sorry, this is not what some of you wanted to hear and it is contrary to popular belief in NZ. Remember, popular belief does not mean it is right.
If you don’t take my free advice, it will not be long before a boat repairer welcomes you to his yard. He may not be as charitable.
Chris McMullen
Auckland. New Zealand.
1/6/2015
Remember – click on the photos to enlarge & read captions 😉
Sodium Hydroxide production requires voltage, salt water and a cathode protected by an anode. this after two hours!
Serious Corrosion overnight.The + is connected to a piece of 316 stainless steel tube
sodium hydroxide build up on cathode after two hours
sodium hydroxide build up on cathode skin fitting after two hours
High quality bronze gate valve with brass spindle
316 Stainless steel tube as the anode after 12 hours
Movie showing gas coming off the bronze cathode The Anode Zinc accelerated with 12 volts – click link below
04-07-2015 Additional reading below on the electrochemical degradation of wood in boats from Chris McMullen.
I have heard that some boat builders/ repairers are of the opinion that bronze and copper stern gear is the cause of damage to the wood in shaft logs.
Their fix is to remove this hardware and replace them with a carbon fibre tube and reinforcing.
Sounds like an answer to a problem that does not exist.
There is nothing wrong with the bronze and copper stern gear, it should last the life of the boat or longer. The problem is the fact, that the hull was bonded and catholically protected with a zinc anode. The unnecessarily protected cathode produced sodium hydroxide (caustic soda) and this chemical destroyed the wood.
Possibly, and likely there has also been an electrical leak and this has accelerated the process. The bonding encourages this scenario by creating a circuit.
Sodium hydroxide is a used to pulp wood chips for making paper!
I ask, why not just renew the wood, replace the existing bronze stern gear and remove all the bonding and anodes?
But no, that is too easy, the unfortunate bronze and copper get the blame and is sold for scrap and the new carbon fiber miracle material comes on the scene.
No one it seems has bothered to look at the ‘Galvanic Series of Metals’.
Carbon is right at the top. It is highly conductive and electro negative. All metals are anodes and sacrificial to carbon.
Zinc is at the bottom electro positive and anodic (sacrificial) to all metals.
So if there is any bonding (intended or otherwise) there will be a current flow from all the metals on the boat through the salt water to the carbon fibre and all the copper and bronze in the boat are anodic (sacrificial) to the carbon.
You now have an even bigger battery sitting in the marina than you had with the bonded bronze, copper and zinc. A floating sodium hydroxide factory! This is working 365 days per year making a chemical that will destroy the wood in your boat.
Don’t believe me? Check out the movie showing my experiment.
You can try it yourself. A piece of carbon tube, an old zinc anode and some salt water electrolyte in a glass or plastic container. Couple the positive of a battery to the zinc and the negative to the carbon. Wait two hours and you will have a thick layer of sodium hydroxide or caustic soda. Exactly what happens on your boat but accelerated.
If you have a wood degradation problem please insist the boat be repaired exactly as it was built and replace the hardware.
Remove all the bonding and the zinc anodes and I am sure you should have no further problems.
However, be aware that a bonded boat will have the dreaded caustic soda round all the bonded metals and that will remain even when the bonding is removed.
Sorry, there is not a lot you can do other than remove the hardware and wash it out.
Sodium hydroxide Na OH is an alkali. It is neutralized by acids (vinegar)
This can be a big job if done properly but less expensive than replacing timber. Stop the producing the chemical is easy and the most practical solution.
If you have already used carbon fibre underwater on a wooden boat (dread the thought) make sure it is not bonded. Do everything possible to isolate the carbon and on no account use zinc anodes.
Bonding and anodes are the biggest risk to our classic wooden boat fleet.
We are only custodians of our heritage boats. Eventually, someone else will take over our roll.
If you want your grand children to enjoy owning a classic wooden yacht, I urge you to remove all anodes and bonding from your boat.
I am an experienced boat builder, not an expert, this is just common sense. I write because I care about your classic wooden boat, unlike your bank balance it can’t be replaced.
The Birth Place of Many Woodys photos ex Chris McMullen ex Gilbert Littler
The two stunning aerial photos above of the Beaumont Street boatyards, taken in the early 1960’s by Whites Aviation, were sent in by Chris McMullen via his friend Gilbert Littler. These days Gilbert lives in Boston, USA but in the 1960’s worked at the Baileys yard (2nd photo above) as a boatbuilder. Gilbert was back in NZ recently to sail on Chris Bouzaid’s Rainbow II during the ‘One Ton Revisited Regatta’, which they won.
Chris commented that back in the 1960’s when the photos were taken, any interested young boy could go into a boatyard and watch what was going on. No health and safety regulations. An older guy told Chris one day “Don’t be a —— boatbuilder sonny ‘’ “Better to be a builder.” He told him the boatbuilding industry was too unreliable, hard dirty work and way under paid. Well Chris says he was right, but he ignored the old boys advice and some how survived, with no no regrets.
There are a lot of woody’s in the photos. Lots of history too. Lowes old yard is just south of the Atlantic oil depot. Chris’s old firm, McMullen & Wing Ltd, set up a travelift operation there to replace the St Marys Bay haul out, taken by the Harbour Bridge approach.
Chris commented that they filled the site with brick and concrete from the Union Steam Ship building. The date about 1980. The site was leased from the old Auckland Harbour Board and had some very restrictive conditions over activity and building on the site. It was too tough and Chris got out and left it with his business partner the late Eric Wing. He sub leased it to Kip Kempthorn who eventually bought the lease and managed to change the terms through negotiations with the new land lord “Ports of Auckland “. Chris isn’t quite sure how he managed that but it happened. What is on the site now would never have been allowed under the original lease. The McMullen & Wing site was next to the old Harbour Board slip and is now called Orams number two yard. As an aside Chris recently bought back their original travelift that has been worked flat out for over 33 years.
The building of a replica 1898 Nathanael Herreshoff triple expansion steam engine – as told by Chris McMullen.
The Herreshoff engine is a triple expansion type with cylinders 3-1/2” x 5”x 8” with a 4-1/2” stroke. It is a smaller version of that depicted in the L Francis Herreshoff book ‘The Wizard Of Bristol’ page 228.
The engine is very different to what the textbooks on the subject show. Everything designed by Nathanael Herreshoff seems to be that way. He certainly never copied traditional thinking but worked it out for him self.
Those interested may notice the two crankshafts gear driven one to one. The right hand one drives the piston valves. Going astern is effected by sliding bush or sleeve within the driven gear activated by a lever, this rotates the valve C/S to a new position. The bush, gear and shaft required machining male and female three start threads, left and right hand 8” pitch! Not easy. The threads have / had to be cut on a planer using a dividing head coupled to the motion. Modern cars use a camshaft driven by a timing belt, similar to Herreshoff but remember this engine was designed in 1898! The engine is very short to allow the crankshaft to be supported by two bearings and also to prevent loss of heat as the exhaust steam travels from one cylinder to the next, thus trying to reduce pressure loss.
If you look at the image of the crankshaft casting (below) you will notice the overhung balance weights. Notice the lack of material in the web between the second and third journal. The crank can’t be ground and there is no easy way to machine the metal designed to be eliminated by casting. Casting this crank was a mission in SG iron. To cast it in steel (with 1/4” to the foot possible contraction) is going to be more difficult to achieve the correct length.
H.M.C.O had an outside foundry cast their steel but I notice in reading a recent article on Herreshoff Anchors they did have problems with their steel castings.
The base of the engine is a bronze casting to hold oil. The engine max revs are about 700 so the engine will have to be enclosed or throw oil everywhere.
There are good drawings available for this engine but no tolerances are given. I guess the fitters knew what was required. The original drawings were coloured to show the different materials, as was normal drafting practice. The prints I got were black and white and difficult to read. No layers as in CAD drawing.
The Boiler is a three-drum type with curved tubes. It is similar to a Yarrow Type boiler. All the circulation is achieved in the tubes, the outer tubes being cooler than the inner. Once the circulation starts it continues. This was proven by Yarrows experiment in the early 1900’s. So Herreshoff and Yarrow, an ocean apart, came to similar conclusions. The upper drum of the boiler is 8“ OD, the lower drums 4-1/2” all with 5/16” wall. The 1/2“ tubes are expanded. Not easy to do up a tube just over 4” ID.
The boiler was built under survey. The working pressure is 250 PSI.
There are no pumps on the engine. The boiler is fed and the cooled exhaust condensate is removed for reuse by an independent steam driven combined feed and air pump. These pumps were the only item on the launch not made in house by H.M.C.O. There were no drawings of these Marsh Pumps made by The American Steam Pump Co., Battle Creek Mitch. I copied mine from ‘Vapo’, an incredibly clever but simple pump with two moving parts but very difficult to manufacture.
I should add there has been no fabrication. Everything has been cast in iron or bronze.
Again this interesting project has been done for no other reason than for my own personal satisfaction. I guess Prof. Evers Burtner’s comments (see copy of magazine article below), I quote “It is too bad that this engine is so complicated that amateurs would not be tempted to build one of their own”, was red rag to a bull.
I visited a rather special boat shed the other day, shed is a bit of an understatement – I have a shed, Chris McMullen’s one is more like an aircraft hanger.
The reason for the invite was to have a look at the 1933 Colin Wild built launch Wirihana out of the water, but what really made me accept the invite in a flash was the chance to view the 34′ Herreshoff steam launch that Chris has been creating for nearly 30 years.
I use the term creating because every piece of this boat (including the steam engine) has been crafted by Chris’s own hands. Its a little way off launch day but already its a piece of art.
Why would someone undertake a project of this magnitude ? Chris’s view is “the whole project is an engineering exercise and an interesting challenge to recreate what was done 100 plus years ago. Further, traveling on a fast steam launch is a great experience and there is something about generating your own power from fire and water”.
Click any of the above photos to enlarge 😉
I’ll let Chris tell the story – read on
“I have been building this (lets say) machinery and boat on and off for would you believe 27 years! I started the project in 1987 –88 the year I sold McMullen & Wing Ltd. Unlike some of my steam friends in the USA and the UK who are single minded,this has not been my only interest, during the time I have owned or had the use of other boats and done many other things. The long winded project, is an embarrassment for me being a professional boat builder. It must be explained that I am not a trained Engineers Pattern Maker, Foundry Moulder, Fitter and Turner, Coppersmith or a Boilermaker. I have had to learn these skills. Believe me, the Herreshoff’s draftsmen certainly did not compromised his design to make it easy for manufacture. The castings for the engine are complex and thin walled. Several foundry’s kindly allowed me to do my own sand moulding on their premises. It would never have been possible without their cooperation. I have had four attempts at casting the crankshaft. The only good casting (currently installed in the Engine) is of material not up to spec. This has been a major blow and I guess my knowing this has set back the job. The 3 throw crank has been drawn in “Solid Works” with the idea of machining it from a solid 9 inch diameter bar of steel on a NC lathe and Mill. A huge job and still can not be completely finished on these remarkable machines. At this stage there is no way to change the design. Crazy, the original was cast and machined in steel over one hundred years ago! I went on and built the 34’ x 6’ 3” x’ 1’10”hull exactly the Herreshoff way (with a mould for every White Oak steamed frame) The hull double planked carvel style and glued with epoxy rather than set in shellac (as was the original) The planking was two skins of 5/16 NZ Kauri. So thin it could not be edge set. On the bilge the planks were made from thicker stock as they had to be backed out (hollowed and rounded) Very easy to loose control of thickness doing this and I believe Herreshoff Manufacturing (some how) steamed the round into the planks. I have a steam box, experimented but could not make it form the planks. I could have built the same boat double diagonal in a fraction of the time but the design scantlings would have had to be changed. At the time I wanted an exact replica! To what end? Now, I am not sure. (See below Vapor) Anyway, the hull is basically finished with the boiler engine and water tank installed ready for the plumbing. For those interested the design is HMCO design # 263 it was built 1908 as the Starboard launch for the Beautiful Twin Screw Steam Yacht “Cassandra” Cassandra was built for an American owner by Scott’s at Greenock. Scotland in 1908 .She was 238 f.t O.A.L and could travel at just over 15 knots. Her tender was designed and built in the USA would have been “State of the Art” at the time and most likely the fastest launch available. It would seem to me there were excellent Steam Launch builders in the UK. Simpson Strickland and Liquid Fuel Engineering (Lifu) and others but the owner chose the Herreshoff design / build. I have a copy of a letter written by Francis Herreshoff (the designers son) stating these launches could do 14 knots. To many, that seems unlikely but I have been on two Steam launches on Lake Windermere that can do 13 knots, so lets say we do not know. These launches are proportioned closer to a rowing eight than a normal hull. On design #263 The boiler pressure is 250 PSI The propeller is four bladed 22 x 30 inch pitch. the Hull and machinery is light. The shaft is low angle and the weights well forward. The speed and shape of “Vapor” a similar steam launch has been discussed at length on Wooden Boat Forum I have never got involved in the discussion but I am very familiar with “Vapor” and know the owner. Ed Louchard a boat builder from Port Townsend has done a wonderful job of building a replacement hull. Vapor is the only surviving Herreshoff Steam Launch. The hull had been re planked at some time but the machinery is all original. Regarding “Vapor”, when I started my project I thought there were no Herreshoff Steam Launches in existence. I tracked down” Vapor” and her friendly owner in California about 12 years ago. Now she has been rebuilt it sort of makes my replica surplus. In some ways procrastination has helped as more information about these remarkable launches comes to light from all over the world. I have enjoyed the research but now I am looking forward to finishing my project but it does get harder as one gets older”
Built in 1963 by Brin Wilson.Designed by Billy Rodgers and is what the owner calls a classic ‘Sounds’ launch.
At 34ft and built of triple diagonal kauri planked.
Powered by a 72 hp Mercedes 4 cylinder diesel engine, she will cruise at a comfortable 7-8 knots.
Currently residing in Motueka and for sale on trademe.
Anyone know how she ended up in the South Island & what of her life in between?
06-11-2015 Chris McMullen Input edited by Alan H
Morrie Palmer of Devonport built the hull and Mr Neil Wilson finished her off. Not Brin Wilson.
Mr Neil Wilson (I believe an ex Joiner) was the owner and manager of the Auckland University Maintenance Department. He wanted no Butt blocks in his new boat and scarfed the planks himself while we built the boat. She may have been 34 Feet but was not triple diagonal planked. (That was later corrected.)
I started my apprenticeship with Morrie 16th of January 1961 and transferred to M C Carter Ltd 30th of August 1963. I worked for Morrie two years seven months.
When I started he was working in his backyard at Point Chevalier. He was finishing Basl Kelly’s raised deck Stewart 34 Pania. I recall a huge launch hull on his section painted with red lead. I am not sure but it may have become the “Lady Argyle”. I never worked on her.
Soon after, Morrie moved to #15 Clarence St Devonport. (see the Cara Mia site for more https://waitematawoodys.com/2014/01/17/caramia/ ) Cal Crooks joined us. Morrie and Cal had both worked for Colling’s and Bell and were very competent workers. I was only the apprentice boy. It was high productivity and had to be as boatbuilding was a competitive cut throat business. At Devonport at least five major builds took place Cara Mia, Lady Ethel, Venture, Oranoa and the Stewart 34 Phoenician. All that, along with repair and insurance work all done, by three people (average) in just over two and a half years. Sure they were hull only or hull, decks and super structure. Mostly the owners finished the job. “Oranoa” was the exception and largely complete and later launched from Devonport wharf
Morrie had very little machinery. It was measure and cut once boatbuilding, nothing fancy just get the job out. His call at the end of lunch break was. “This won’t Grace the Harbour” Lets get on with it.
Morrie owned and cruised with his Family the twenty Six Foot Mullet Boat “Omatere” previously owned by Basil Kelly. It may have been a trade in on the Pania.
Morrie was very keen on Mullet boats and encouraged me to build one. She was the last planked Mullet Boat. The 22 Foot “Tamatea”. I built her while I worked for him. I bet he later regretted his action. I was building the boat after hours in my parents back yard and it must have affected my work.
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