Giving Our Boat An ULTRASOUND - Episode 7
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- čas přidán 5. 11. 2023
- In this episode we get to test the thickness of our hull using an ultrasonic thickness gauge. We also prepare the boat for the upcoming storm making sure the boat is secure.
If you would like to support us with this project so that we are able to give you videos and content then please see the link below:
buymeacoffee.com/duovagar
Info Regarding narrowboats, insurance and more as used in our video
www.whiltonmarina.co.uk/Narro...
She's 100 yrs old ..........and has quite a few years left in her , most importantly get her out of the water and blasted , and you're NOT making a mess of it .
Definitely needs dry docking to be able to assess the hull and get it all sandblasted.
In general, I would say today - with the metal you can get on the market - you should always sandblast it if you want or have to restore something!
Personally, I would be very careful with these iron sheets on this narrow boat: you can get layers of paint and coatings - whatever - off with sandblasting.
But iron sheets themselves should not rust if they have a protective coating.
Rusting is an electro-chemical reaction: with "modern" steels with a small thickness and rather inadequate protection - the only way to provide a kind of rust protection is through the proportions of the added alloy components!
But it's worthless if you put material in the sheet metal that rusts quickly - for example self-tapping screws.
If the iron sheet is in proper condition and has a moderate protective layer, iron can be more durable than any refined sheet metal known today!
So I would just check the whole narrow boat and provide protection for these structures.
Honestly, I have no experience with this - but the fact that it has lasted for over 100 years without any problems - gives me a lot of respect for these things.
I would try to do it the way the manufacturers made and protected the narrow boat!
Maybe you could use chalk or similar to write your readings on the hull as you go. You wont be able to remember them all ;)
@@aeros4me :I have cameras, notebooks and tablets and CAD (computer aided construction) software - and I think our two hosts here work more efficiently than many professionals: they write everything down meticulously and create a lot of work for themselves!
As a developer, designer, system planner and process developer, I think - in practice, only identified errors count: and only those have to be marked and kept in mind!
Work doesn't have to be wrong: you just have to be conscientious about what you do!
My own attitude does not reflect the professional work: as a pensioner, I have the freedom to work like this - beyond norms, regulations, guidelines - which intervene in a solution determined by others.
That makes my work more successful - because efficiency and money spent, costs are the main determining factors - and how to complete a task as effectively as possible!
If not later - when the narrow boat is inspected from the outside in the shipyard - serious errors will be discovered (the shipyard is also rather dishonest, they want orders: in England there are very sincere and honest, also direct people, which I really like guess) - which I actually don't think so at the moment - there's no reason to exaggerate anything!
It is important that as the owner you document everything on site and inspect it yourself - also in order to obtain a good and complete description and documentation of the narrow boat, which, in my opinion, would be absolutely necessary given the age of the ship.
Of course, our two hosts have made mistakes so far - in my opinion - but that's normal: I'm more of a technical person who carefully documents, photographs and films everything.
I'm only doing this because a lot of things can come out later that you didn't notice before!
This never happens to me - it always happens to others!
This shouldn't be a negative attitude towards others!
A shipyard only does what it is commissioned to do: here too things can go wrong: consciously or unconsciously!
All companies have ways of working - but they are usually not particularly good, efficient ones!
So: be there yourself and be careful what you sign!
When I helped restore European classic cars in England, my biggest problem was that they didn't have anyone who knew anything about wood, but that's exactly what the clients demanded!
So we taught each other the necessary knowledge about components as wood and the necessary wood processing methods: that didn't hinder the actual work much!
In England there are still saddlers who can make a good top - but you realize: a lot of things are dying out! and the replacement today - is something that has become very bad - today's leather and artificial leather are - just shit.
Actually, you should also be able to manufacture and reproduce engines and engine components yourself: there are many problems that customers don't get to know directly!
This would be remedied if people would design and build new vehicles of the past and present themselves - not as a market factor - but only as an individual aspect of vehicle construction!
I am working on it!
Kind regards from Berlin, Germany
Clearly the vessel's hull should be surveyed ... prior to purchase.
The frames as well as the hull.
If any overplating on a hull that old then suggest you think twice ... on the premise that repairs on repairs could be eyewateringly dear.
Yes they know, it's just they missed the window to get it out back in sept/Oct so they can't do it till next year. this was just a check to make sure they don't spend the next 4 mo tha working on it only to find the Hull was too thin and not worth the effort. but all good just a few spots to keep an eye on.
To get a more accurate reading use a grinder to bring it down to bare shiny metal
And calibrate against some new metal.
As shown at the beginning there is a calibration disc with the kit. I think it was 10mm.
So she's solid and ready for restoration! Yayyy!
Just a suggestion. Mark your soundings with chalk then record them with the measurements between the frame stations. This way you can have that at the ready for your insurance co. And yes, ultrasound gel is good to use to get the most accurate measurements. You got a nice tool to do the job. This is going to be a really neat build out. You will have a nice home when done. Take care and be safe!
Hi,
I am an ex ultrasonic technician and here are some tips on ultrasonic testing to assure accuracy.
1. scrape clean the surface of all debris and paint.
2. Use wallpaper paste, oil or Grease to assure good coupling between the probe and the material being tested.
3 taking measurements through paint is not recommended as paint has a different sound velocity also the paint may not be adhered soundly to the metal giving an incorrect reading.
Good luck.
Check your instructions. Im pretty sure you need to grind the measurement area to clean steel and use a gel on the sensor to get a proper reading. Being a riveted boat it has some age and will most likely be made from heavier steel than welded boats.
ben and emily recently had their boat two packed. the company that did it sand blasted all the bottom and tested everything for depth or holes and welded everything, then did the two pack coating. proper job. maybe go check out their video on that and see what company it was? 🙂
Hi Chris and Priscilla, thanks for braving the deteriorating weather, along with lots of bending to take readings to make the video. Keep in mind that your ultrasonic tester is only measuring spot samples around the hull, you won't know exactly what condition the hull is in until you visually inspect the bottom side. The good news is, there are no active leaks and since the boat has not completely rusted away, I assume better materials were used in the construction.
Boat designs have changed a bit over the years since your boat was made. In addition to the rivets, different metals were used, different standards were used, and of course, measurements were not in Metric.
It is clear you two are not boat maintenance experts but, you will learn huge amounts you probably never thought possible in the next few years. I wish you both the best!
The gauge is measuring the round-trip time of a pulse of sound time through the hull. There should be a way to calibrate using a measurement that you make on the boat. itself. Use a caliper to obtain a known thickness and use that for calibration. The gauge learns the speed of sound of the metal on your boat and uses that to calculate thickness. Paint is much slower than steel and gives a higher reading than the actual measurement. It is best to remove paint and loose scale. You might want to create a grid to record measurements in an organized way. Use some light oil as a couplant between the transducer and the metal. I sold ultrasonic gauges for several decades. You've made a good start.
The surveyor I engaged measured the thickness of the rudder with his electronic micrometer, then the ultrasound kit for calibration purposes.
He used a gel on the "probe" and scraped the blacking to the metal. This was pre re-blacking of course. Then chalked the readings by the test site.
If arsed search YT for video(s) of hull thickness surveys.
Lol, the dog's thinking "F this", standing out in the rain
I can’t wait to see an interior start going in this boat! I think you can ease your minds just by looking at the construction rivets on it! Definitely looks like it was built to last! Good luck to the two of you!
Built to last as in construction but was the metal itself made to last for eternity?
And metal hasn't been repainted in a while ...
" My Long Boat Passed The Ultrasound Test " - perfect t-shirt logo *gigglesnortgiggle* 😂
😇❤
Good news. I think you guys did a great job measuring the hull. Exciting.
Your lovely old boat does look like she has plenty of life left in her hull. A big heavy duty clear tarpaulin, or two/ three smaller ones, weighted down around the outside (perhaps with water filled bottles tied to the eyelets) could help keep the rain out and still let some light in. Temporary installations of a wood burning stove - for dry heat - and maybe even a basic solar panel + leisure battery - for light and phone/gadget charging, would make it more pleasant to spend time aboard. Once you have her more water tight I would be tempted to get some temporary floor boards and basic bits of furniture..... If you're not in too much of a hurry to get her lifted out , you would have more time to choose / get to a boat yard that's friendly and best..... My old barge has a riveted iron hull that's got much more rust and problems but I love spending time relaxing on board....
Riveted hulls are completely different to welded. A welded hull will have plates of the same thickness across each area as you say 10,6,4mm. Your hull will have been built to imperial measurements and being riveted will have thinner plating towards the bow and stern where stresses are lower. Unlike a welded hull yours gains strength from the riveted framing inside. I suspect she was built in a combination of 5/8, 1/2 , 3/8 and 1/4 inch plate (approximately 15, 12, 9 and 6 mm
Thanks Peter we appreciate your insight on steel gauges
@@DuoVagari You having removed rust yourselves informed you on where to test the most. You might want to consult the individual sandblaster with the same kind of question. Where did he remove the most rust? I usually find the most rust at the waterline whenever I look, so test there; also right beside frames right next to the joints, as close as you can to where moisture likes to stay sandwiched between plates.
Dear Duo Vagari.
You know that this should have been done before you bought the boat! Now please get it out of the water at last and sandblast it completely (DIY or let someone do it). Afterwards measure again. Only after doing so you really know the thickness of the remaining metal. 2) I still say that this very old hull is a big money pit.
Best regards, luck, health and wisdom.
The full extent of repairs needed will not be seen until it is out of the water and sandblasted. I have confidence in your determination to see it through. I loved my time in England. I lived in the Oxford area.
It's very gratifying for me to be able to draw conclusions from other people's descriptions about something that wasn't even part of the curriculum when I was studying.
Generally speaking, people are very theoretical - they are never practical in their knowledge.
I spent some time with friends in England at the time who repaired old classic cars from all over the place that had the same structures: endlessly durable things that didn't rust - and even something typically English as a substructure: wood under the sheet metal.
It is commonly said that sheet iron is the only metal that rusts: that is how it is taught!
I have never found anything like this in practice: nowhere!
I once had a 400 liter aquarium: rust-free stainless steel - actually that should mean low-rust steel - then normal materials made of steel were added, for example the power supplies for the lighting - and the supposedly red-free material just crumbled because of electro-chemical corrosion!
I saw a lot of rust: on newer vehicles of our time - on old classic cars there is still very little to this day!
that speaks for itself!
With the iron sheet, there are probably overlaps at the transitions, which explains the values of 9.4 mm - the 6 mm coming from below and the 4 mm coming from above!
looks very good, your gold piece!
Greetings from Berlin
I think what you're trying to say is "Surveyed." When you call in a professional marine surveyor, they will be able to evaluate your entire boat. and should be able to offer certain advice on how to proceed and even offer some budgetary cost. they also have a network of experienced people in the industry. Well worth the money.
Yes good advice and perhaps a professional survey is required for insurance purposes??
It’s a very characterful boat I hope at some point you have it in dry dock especially with these heavy storms. Right now your measuring the difference between rust and non rust areas. Good luck!
Hello! I follow you from Buenos Aires, Argentina! I love the boat project. I'll stay tuned to see how everything goes! Greetings!
Yes to installing new windows, will help in keeping the rain out and allow light in to see what you are doing. Most important is the mentioned haulout / drydock to have professionals check the soundness of the hull and to recoat to keep the water away from the steel, don't scrimp on this as it would be a shame to do all the work and one day find it leaking
I think you have done a great job of stabilising the inside, now to get her on the hard and sandblast and get the it painted then you’ll never look back. It’s been hardwood but I think you have a good hull to build a home in and have peace of mind. Well done
Considering her age and condition those readings are pretty good. The important thing is to do what your going to do, get her out of the water, give the hull a good clean and go from there. She's now in safe hands, which is really really good for the old girl.👍
I've come along for the interesting journey of how thing go to plan or not on a narrow boat 😊 You far more brave than i am. Looking forward to the next chapter. Regards from Gauteng, South Africa 🇿🇦
While those measurements might not be enough for an insurance company, they give you the confidence to move forward and that's what you needed for now 👍
Now you have the machine, maybe investigate what it takes to get certified as a professional surveyor, could be a good side hustle to top up the kitty as you travel.
Would recommend calibrating you unit of a 10mm blck of carbon steel , make sure areas tested are rust/corrosion free, if you unit has the capabilities of ehco to echo then you can test through paintand will therfor duduct the paint coat to give you true reading. you have to calibrate on carbon not stainless steel as the velocity will be out not much though 5960 is what you want for carbon steel, also use some gel/ wallpaper paste as a good Couplant... Have been using Ultrasonics for 20 yrs from oil rigs to wind turbines
Hull yes! Carry on. Actually I'm enjoying watching you bring this beauty back to life. I was a music man all my life and tho somewhat retired now, I still make music vids for my youtube channel. But in there somewhere, I remodeled two houses and built two recording/video editing studios but I never did a boat. At 79 I'm not likely to now lol! But it's fun watching you two have a go at it!! New sub who is now binging to catch up with your efforts.
Thanks so much!! Welcome aboard and thanks for sharing:)
Agree with Michael-ln7us get it dry docked and sand blast or Laser Clean the hull before you paint. Get a much better finish and you can be sure there are no hidden surprises
I’m really enjoying this series x
Thanks Angela we appreciate the positive feedback. Thanks for watching:)
Doing this before the hull has been sand blasted you could be getting false readings. As you will have rust build up on the bottom of the hull.
It will be amazing when done
Hi guys. While you’re ultra sounding, remember the deeper pitting will probably be on the outside and would typically be around the bow, at roughly waterline level. Exceptions would be if shore power has ever been a feature of the boat and also anywhere there are noble metals present, such as a stainless shaft.
If you can ballast one side to induce a list, you should be able to see the hull at the waterline, on the high side. Check in all the deepest pits. Don’t be surprised to find as little as one mm. The miracle is that there are no actual holes. Nothing you can really do around the stern gear, until she’s lifted out. Cavitation and simple friction with the fast moving water, around the prop, can eat away coatings and create an oxygen rich environment, so you may well find some very deep pits around there. The great thing with heavy metal is, nothings unfixable. Also, once you get the hull finished to an acceptable standard and the motive power sorted, you can use the boat while you work on it.
Even with no interior at all, a sunny day trip along the canal, with a picnic lunch on the roof, followed by a return to base in dusk can be a very pleasant experience. Knowing that she’s all yours and doesn’t have to be returned at an ungodly hour of the morning, cleaned throughout, makes any visible flaws a trivial affair.
Thanks Duncan by the sounds of things you have some good experience with metals and corrosion. Hopefully when we take it out the water and we get it professionally measured the boat is within tolerance fingers crossed!!
We not sure if there was shore power previously as we can’t see any evidence of it at the moment. What your saying about cavitation and thinner material around the stern is spot on we did notice a hole that will need repairing but luckily it’s above the water line currently. Thanks for sharing your knowledge with us & for watching:)
that was a good idea !
Speaking from experience with a 1929 Josher rivetted hull, the most vulnerable places will be on the chine behind the knees. We thought our hull was sound, but behind the knees was where she sprung a leak. After a second look , we found several places that needed work.
Thanks Tony we appreciate your insight we will be sure to check this over thoroughly. Thanks for watching
Hi guys looks like she's stood up well for the age, can't wait to see it out of the water though cheers 🥂
It might be a good idea to wire brush and clean the rusted area to be tested, and then draw a circle on the tested area of hull, and number it. A paint marker pen works well. (These are your distance range points, also called "gridding")
They allows you to draw a proper numbered corrosion map.
This grid map will form part of future survey document pack.
I've done surveys of supply vessel working decks with more than 700 reference points, allowing you to plot the thinned areas requiring re-plating accurately.
And always remember.... your hull rusts from inside....
Not from outside... (as it's protected from corrosion outside under the waterline by anodes)
I would definitely recommend sandblasting (or at a minimum needle-gun and wire-brush),the hull inside below the waterline, to remove the oxide scale still remaining under the paint you applied.
Anodes do not stop rust, anodes stop/slow down electrolysis erosion. Corrosion/rust are nothing to do with anodes, rust is caused by oxygen, iron and moisture combining
So for the last 30 years at Shell & Bp we have been mistakenly checking anode depletion (and doing routine replacement) on unpainted subsea offshore oil structures and platforms?
The anodes galvanically erode instead of the steel rusting away....
Why do you think subsea jackets are unpainted?
But say what you wish, everyone is free to have their own interpretation of what is occurring.
This barge will have much higher measurable internal corrosion and pitting on internal faces of the hull plates and frames than
on the outside.
Let's wait and see what the surveyors grid map looks like.
The measurement of the steel plate would be imperial size not metric also the rolled plates would be iron not cast iron but wrought iron .when your bout was made From the 19th century onwards, ships began to be built from iron and steel.if your lucky they will be early steel .
Hope it all goes ok good luck 😀👍👍👍
Thanks Tracy 😃
A it floats all good to me have fun 🤗
You are going to have a wonderful end product
Yes it obviously involves a great deal of both hard work and financial commitment but it will be so worth the effort ❤
Thanks Jennifer we think so ! But a long road ahead :) thanks for watching
If you sand the spot then a few drops of glycerine smeared on it will make a world of difference in accuracy.
So overall pretty solid! Congratulations 😅👍
Thanks! 😁
I would be very happy with those preliminary results, a bit of peace of mind.
You need to do the test on bare metal, didnt it say that in the instructions?
Hello from Kansas! I don't know how it is in Britain, but here in the states the insurance companies would demand a certified person to perform the test and even if you are certified, they would demand a third party do the testing. Gel is a must for accuracy and any paint or rust scale will throw the test off. I'd also question if the hull is actual mild steel or wrought iron, being as old as she is. I'm not sure if the settings would be the same or not. Hopefully everything turns out good! I'd stick with your plan of getting it out and tested by a professional. Thanks!
Hello Richard thanks for the support! Yes definitely we will get a professional to check it for us when we take it out !! Hopefully very soon!. We just did this in the meantime got our own sanity and piece of mind as we continue to spend time and money on this beautiful boat 😃
Awesome
I've been almost 20 years aboard now. I remember when the canals were the UK's best kept secret.
I suggest you take a look at Flying Coney hull welding hull pitting . It is doable by welding holes or over plating.
Excellent work guys! At least she is still a bit chunky 🙌
You could try it on one of the ribs to get an idea of accuracy, seeing as you can actually measure how thick they are
when she comes out for blasting and hull repairs...spend a little more money on a high performance coating............that will slow down the rot and save you money in the future.
I think you may need a ultrasound gel. between the prob and the metal. It will give you a more accurate reading. The gel helps move the sound waves.
Best to mark up the thicknesses with a paint sharpie, especially areas that are below average thickness. Looks as if things have turned out OK but you won't really know until blasting is complete.
Lekker julle! May I suggest a wire brush on the grinder, or a flap wheel, just to get the surface smooth, and the a quick spray tin dot in a light colour. Then record the thickness reading on the paint dot. Call me pedantic, but that is what I would do.
More tea and crack on.
Seems like a good general idea. Hopefully sandblasting it wont drop it too much further. As you can see anyways theres marginal points where you expected it to be. So really confirms it will need work in those areas. Hopefully the rest ends up well within spec for full insurance and you can treat and save this boat. Personally id be iffy about ordering windows until the pros do their bit. I been caught out before getting way ahead and losing heaps. On cars tho not boats. But yea sometimes best to wait for full confirmation first.
Добрий день, для якісного вимірювання необхідно обов'язково зачищати поверхню до чистого металу, інакше буде велика похибка.
Зазвичай для зачистки металу використовують маленькі кутові шліфувальні машини.
При зачистці обов'язково одягайте захісні окуляри.
Гарного дня і плідної роботи.
The hull will have been 3/8" imperial originally (~9.5mm) and likely been plated where you are measuring more. The upper structure was probably 1/4".
Your barge was clearly built quite heavily, which is good of course and could save you a lot of money if there 's no replating needed.
Although readings from the inside can be overly optimistic, as you can't see the condition of the many rivets, and possible deep pittings.
The only valuable check-up can be done in a drydock were you can actually see possible pittings and headless rivets, if there are any.
The wind waterline is where the hulls suffer most (normally).
I help you hoping for the best, good luck with this big and interesting project.
Well it got to be sandblasted,reading after that is your mm ✌️
I am surprised you didn´t use a couplant (glycerine) to get better readings. Unless the gauge used was a double backwall echo type to negate paint thickness your readings on paint will be optimistic. Speed of sound through paint is less than half the speed through steel therefore if the is 0.5mm of paint it will register an additional 1 - 1.3 mm of steel thickness. We used to do thickness readings underwater on the outside of the hull as the water acts as a couplant. I always argued it was a good news gauge as where you couldn´t get a reading the backwall (for our divers the inside of the hull, or in your case outside of the hull) was most probably heavily pitted resulting in scattering of the echo. As others have stated, calibrating to mild steel on a hull this old is probably also giving errors.
It's going to be A beautiful house when your done. I've seen A few of these boats fixed up.
Hope so! Thanks for watching
To be sure of readings, measure a rib , compare to calipers
The best way is to take it out of the water and do sand cleaning. After that epoxy painting.. and from there you can do what you want
There are some very good suggestions here, in the comments, so you should be able to proceed without much worry. Personally I’d pull her out of the water for winter. Much easier to access in the weather that is coming. Interesting comment down below is the rusting coming from inside the boat. It always does worry to see water inside a hull, I guess that’s why bilge pumps are so important. It raises the question though how to access your bilges once you have built your inside spaces. Plus what can one use that is a long lasting sealant. Good luck.
I imagine when you haul it out & sand blasted there’ll be areas that need pad welding, areas that need plating and areas that simply need a lick of anti foul. I guess the good thing is, you know you can walk inside without falling through 😉
I don’t know what the instructions say, but every ultrasonic I’ve seen done uses a small dab of Vaseline between the probe and the metal in order to get better consistent readings. You will also get the thickness of paint so scrape or grind back to bare metal. Then be methodical and create a chart and mark on where you are taking the readings then when you do it again you have a reference. Well done though, owning a boat is like having a baby, it needs constant love and attention.
A £50 Tool from amazon isnt going to give true reading is the water only been a boat builder for nearly 50 years but its not my boat.or money it needs to be out on hard to be tested also needs to be clean metal to be tested
Thanks ajw we know this but we just wanted to have an idea of what we were dealing with in the interim until we are able to take it out the water
@DuoVagari will.just give false readings my ultrasonic tester has be calibrated yearly and cost nearly 3k its impossible to give accurate readings in water and without bare metal plus gel tool only fit for bin
@@ajw1467 :Today, an inexpensive device is not necessarily a bad thing: my devices also require documented and confirmed calibration every year.
What is calibration: you limit the measured values determined to the range you want!
I think that inexpensive devices with calibration solutions or similar for self-adjustment also provide usable equipment!
Today, the purchase price is not a general indication of something good - there are a lot of providers who provide worse service than roughly tolerated devices!
I seen a regular canal boat on the intercoastal waterways of Florida. There might be some utube on it.. Think there was s lot of rock and roll going on. I had a house boat on the Alabama Byou . 60 ft by 20 ft. To many huricans..guess you could take it up the Siene..i guess its always a good resale item. If you got correct surveys. I would get nuts with the interior. The next people will want there own. Seal the inside hull again over winter. Get your bilge pumps in..maybe balast..
Wouldn't get nuts with interior. Get recycle materials. Maybe some kind of underfloor heating system. You can get twelve volt mats. Good to have warm feet in the winter..you have to run a geny..
I like extremely low power operation. I have seen how very small engines can push very big boats and enjoy seeing more of that. The rule for auxiliary sailing schooners was 1hp/ton, which you are well over, right? No wonder I haven't yet heard full throttle.
Little tip go find a rusty peace of plate ,test the thickness then clean the rust off a section an pd test again,you will be amazed at the difference a lair of rust makes.
I had a survey done a narrowboat and found out the topside was 3mm hull was 4.5mm and baseplate was down to 1mm in places. so yep bought it and had a new 8mm baseplate put on it. i also found that the hull sides where down to 1mm where they had been welded together which didn't show up on survey.
Those rusts you covered gonna eat your boat further soon. you definitely need to get this off from the water and give a good sand blast everything.
Given the age and riveted construction of your boat it is likely to be made of wrought iron not mild steel ,which will affect your readings. Also age related the boat would have been built using imperial thickness materials ,converting your metric measurement to imperial will give a better idea of wear.
Good luck with your new old boat i look forward to seeing the progress im American i would be installing twin turbo v8 engine
A MAN engine..for exemple ..bi turbo
@@schirmeyerb yes im im sure hahah i was just joking about the V8 engine
@@mrr8697 you can put a MOPED ENGINE......you are COMEDIAN
This is a very interesting project on the cut. 😊
I don't want to be impolite or so, but do you have any kind of, not exactly a budget, but maybe some economic plan for the project?
Nice to have the peace of mind till you can get a haul out, and inspection.
I think that the bow area is fine your issues are more likely to be the very bottom as your barge has a shallow Vee, most modern narrow boats have a flat bottom.
If you talked about my wife like that,expect a shiner !
I thought you had to grind back any rust or paint to the bare steel, to get a true reading of the thickness. At least it saves you some money doing it yourself 👍👍
Usually just a scraper to get mud and greenery off.
It's not an exact science. If the metal gets down to around 3mm then overplating might be appropriate.
Some surveyors are not that keen on over plating and some advise cutting out the thin stuff and replace with an insert, as in weld and grind.
The reason being that metal eating bacteria inhabit the gap between the hull and overplating.
That said it seems a tad purist and just how much metal can these bacteria eat anyway?
Info to be found on marine surveyors info website.
Just Google if arsed.
Redo the thickness again straight after blasting .👍
Good news
Well, now you know she's NOT tissue thin and about to fall to bits, but Yall should still put her on the dry, sandblast and re-measure. I strongly think the old girl would be much happier with some new plates in a few spots.
Barley tried to steal the stage. No need to stress. The hull is not leaking. If anything needs replacement, that can be done when the boat is hauled out.
you can have patches welded on the thin spots.
I used to work in a boatyard and I used to angle grind any paint or blacking on the hull ready for the surveyor to get a proper reading, hope this helps?
Thanks Paul definitely thanks for sharing your experience we will try this !
Never had any experience in such things. Do the inspectors use the ultrasonic gauge over the paint or with the paint removed first? I ask because if they read over the paint, the paint thickness will absolutely be changing depending where it flowed to before drying... IDK
Good to know for sure the boat isnt pregnant😄
Judging by the age of the boat a d it's construction, isn't it iron, not mild steel?
Could possibly be but fortunately it’s the same settings on the machine
It's hard to get the coating evenly if you do it by hand, spray machine is the way to doit properly.
When are you hoping to getting her out of the water because i would certainly think of getting it out for a proper piece of mind 😊
Took a while to work out what hole you were measuring until I realised it was the accent.
Wouldn't have thought anyone's replated it with rivets,unless it was done in a ship yard, also uniform thickness over huge lengths in those days probably not as accurate as today.xx
I would of got it out of the water by now that way if it's thin it can be fixed safely on dry land so it won't sink
due to the age of the hull, i wouldnt cut and re weld. todays steel is not a patch on that old steel. welded new in isnt the answer. these areas will corrode quicker. sand blast or wire brush, treat with a rust inhibitor, then good quality primer, then suitable top coat. i would say the hull could very well be thicker now then a lot of modern boats. but what do i know!!!!!
Thanks Geoff we tend to agree with you, this hull is definitely made with a good grade of steel due to her age
Having seen your widow frame removal, they look like either bus or coach windows. You could source new glazing from a breakers yard, which would save you loads of dosh ....
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Curious do you have to have insurance to use the canals?
Yes insurance is a requirement to get a canal license
Dry dock it she a good ole girl wide too can get that for price any more blast it and coat it a few times thing will be around for the next hundred years sandblasted two coats of marine primers and three coats of marine grade paint is about standard.. 💪💪💪 weld some railings on top have a nice partying area
Remember your boat was built with imperial gauge plate. 1/8, 1/4, 3/8 inch etc. Not metric sizes.