I been bit by the Roamer bug and am looking to buy an old beauty as a restoration project. Of course, no use restoring something that doesn't have a sound hull. Problem I'm finding is that the reputable surveyors in my area admit they don't have the expertise to give a proper assessment of the hull. I've found a company that will ultrasound the hull to measure the thickness of the steel. I've heard audio gauge is the way to asses hulls, is ultrasound an acceptable method as well? Question is... what is the original thickness and what would an acceptable thickness be. The boats I am considering are a 1964 - 38' offshore (which I love the looks of) and a 1961 - 31' riviera. Any tips or suggestions on how to identify potential rust spots other than just looking for rust?
On my 1961 35' Riviera, my sides are 11 gauge and the bottom is 10 gauge in the aft and 3/16" forward.
I think you may be talking about the same thing. Ultrasound is a term used more in the medical field for looking through at something where audio gauge measures the thickness of what the sound goes through. Both would be using penetrating sound waves.
Here is the response I got from a company willing to assess the hull. Since this will be my first time with something like this, does this sound like reasonable process? Since these are spot tests, any advice on where I should have him focus his testing? Thanks Yes we can perform Ultrasonic thickness measurements on steel plate. The instrument utilizes a 1/2" diameter probe which must be coupled to the steel to be Inspected the thickness of the plate is the thickness directly under the Ultrasonic Probe.(Spot Check) The amount of Inspection is up to you, keep in mind the amount of Inspection should be clearly stated. Also what will the criteria be ? Any original info regarding the construction of the boat would be a great help. This type of Inspection is commonly referred to as a corrosion survey. The surface of the plate must be smooth & clean to establish accurate results.
Hi, Call a surveyor who knows what they are doing not someone who is just starting out with steel boats
I've tried contacting a few reputable surveyors and all gave the same reply that they don't have enough experience with steel boats to conduct a steel hull assessment. The company willing to do an ultrasound knows what they are doing with respect to testing steel thickness using ultrasound but know little about boats. The hull and stringers on the 1964 offshore I am looking at appears visually sound from the inside and outside (i.e. no visible rust bubbles or flakes) but we all know that looks can be deceiving. Given I can't find a surveyor to audio gauge the hull, I'm just wondering what other options I have.
Hire a surveyor from another region. If there are none in your area (which is very hard to believe unless you are in Kansas or Colorado) you will have to pay for someone to come in from someplace else. This is not rocket science and there are hundreds of survey firms with steel vessel experience. You might increase your chances if you don't limit yourself to recreational vessel surveyors. For the price of doing that you can buy an audioguage and learn how to use it yourself.
Hi, I gave this guy the name and number of an outstanding steel guy from FLL who also has a close colleague who hails from a marine based family in Thunder Bay originally so between then they should be able to guide /help the guy to get a fair deal and an decent appraisal of his potential money pit.
I had a few guys with experience in building steel hulls look at mine. One guy use to build yachts, and the other had previous experience in working on fishing tugs. Both agreed all that really mattered was the stringers. The previous owner had welded a fair amount of steel on the weak area's,and even area's that had bled right through. Both agreed, band aid patches are the easiest and best way to go. I used some fill on the edges before I epoxied the bottom of the boat and you cannot see where the new plate is at all. A few argued you will eventually get rust in between the repairs,however, they also pointed it took 46 years for the rust to become an issue in the first place..lol Anyways,all along my keel has had new steel welded in,as well two places near the front,and one large area underneath where the engines are.It all turned out very solid, and I am happy with the result.
Check with whatever insurance company you intend to use. They'll have the number of spots they want tested, where they want the surveyor to focus, and can maybe even suggest a few guys who can do the work. You might also check the Society of Accredited Marine Surveyors (http://www.marinesurvey.org/index2.html)