I have been Surveying quite a few Wooden Broads Cruisers again recently. They are very appealing to newbies to boating because for one reason they look like a real boat should, and also because of all the room that's available.The biggest reason buyers like them is the cost. You can quite easily find a six berth, 35 ft Broads Cruiser for under 10K. In fibreglass you would be lucky to get a diesel engine thrown in for that price!
Lets start with
the point that there are many Surveyors who are no longer in the business after performing pre purchase surveys on wooden boats. I almost gave them up myself years ago because surveying wood boats is fraught with risks. I've only ever owned wooden boats and at the ripe old age of 52 i now actually live on one myself. Saying that, mine is not a Broads Boat. Most Broads Cruisers were built just to hire, they were never meant to last for years and years and generally the majority of them were not particularly expensively built in the first place. Saying this many have been proven to be
persistently durable, and are intact and with no indications of serious
distress. Remember they are only being used on inland waters, they are not expected to cruise across the channel!
Lets begin: Concealed areas within a hull are always a problem but, most Broads Cruisers are constructed in such a way that enough access is available to
make a fair assessment. I always pull up all the floors and remove enough paneling that I can get a fairly good glimpse of the bottom and the lower sides. Carrying an
electric screw gun is a must in order to do this quickly and effectively.
My biggest job is removing all the internal fittings. That means I have to move a lot of mattresses, bedding, carpets and empty out lockers, etc. Once the interior is opened up as best possible, Im ready to begin.
Three important tools are a slim light crow bar, the sort used for pulling nails. A light hammer and a standard
blade screwdriver. I check the joints between planks and frames visually, looking
for gaps or any sign that the plank is not tight against the frame. I then use
the screw driver to test the wood for softness on both plank and frame near the
mating surface. You should be very careful with your screwdriver or spike as they can be destructive! Many a Surveyor has got into serious trouble after the boat owner found thousands of spike holes in the bottom of his boat!
I occasionally try to slip the crow bar under a frame and pry gently. If the frame moves, there is a fastener problem. I do this at every
opportunity along the hog (internal keel) or chine area. Often the frame ends are split or
soft, repairs are usually necessary.
Certainly its not feasible to go through the entire hull testing all frames and planks in this manner, and fortunately it is not necessary except for the keel area where this needs to be done wherever possible. Further up from the keel, I can limit the physical testing by looking for signs of weepage. Anytime there is evidence of water migrating through seams, corrosion of fasteners has to be suspected. Weepage shows up in various ways, often depending on whether the wood is painted or bare, its age and so on.
Use the screwdriver for testing the hardness of the inner planking, particularly in the deep bilge or any place that is wet or looks suspect. The screwdriver blade is just the right tool, and if it goes into the wood, you know for sure that its deteriorated. Poking around like this is quick and easy so that most vulnerable areas can be quickly covered.
The chines are an area not only of high stress, but an area that is also prone to leakage and rot, and most Broads Boats rely on the chine for most of the hulls strength. The surveyor should take every opportunity to inspect the chine areas and when evidence of weepage is found, the area should be targeted for special attention to rot. I often find large areas of rot on the chine stringer as water leaks in through the deck joint or deck fittings and it accumulates on the top of the chine and can cause major defects over time. (see lower picture).
Bottom Frames are often joined to side frames with very little on Broads Boats and the chine takes the brunt as no knees are fitted. Looseness, rot or corrosion on these chine fastenings is a warning sign that all is not well.
A steel strap helps support the chine timber here, but this is unusual and most broads boats reply purely on the plank fastenings to support this area. |
The intersect of bottom and side planking to the transom is yet another area where leakage and deterioration are prevalent. This area is also often difficult or impossible to reach, being obscured by fuel tanks and exhaust pipes and whatnot. On larger cruisers you can strip the aft berth out and get in, but on Broads Yachts you may only be able to see the inner corners by using a mirror or camera, unless your very small and you can climb in through the transom hatch and around the rudder tube. If reachable, probe the wishbone transom frame from both above and below. Broom Cruiser, Navigators, Captains and even the Admirals suffer in this area. (ventilation problems). Probe from the intersect of bottom planks and frames, and transom plank and frame. If the wood is at all soft, the problem is serious and needs further opening up and investigation. Examine the intersect all the way up to deck level. Is there water leaking in from above? If so, what is it doing to the wood and fasteners? Check from the exterior: are there open seams and signs of rot on the corners? If you see it above the waterline, what's going on below? Remember that open seams are allowing rain water in, and fresh water can be disastrous.
Keel bolts are always difficult to inspect or comment on. Check these major structural
members for signs of working. Look for unevenness of scarf joints or any other
signs of movement or working. Probe the keelson with the screwdriver for
evidence of softness. Check the intersects of transverse frames for signs of
rubbing or chaffing that indicates movement. Check visible bolts and bolt heads
for corrosion. Also check for discoloration around the bolt heads. If the wood
appears white and soft, this is an indication of weepage. Be careful about diagnosing this as
"electrolysis." Its probably not. I always suggest the
removal of at least two sample structural keel bolts for examination of the
fastenings and adjacent timber material. This task is obviously difficult and sometimes impracticable and should be approached when
convenient, especially when there was no evidence of deterioration of the structural keel
bolts or surrounding timber.
Black Bess (Ernest Woods Halfdecker) which i have a half share in has just had her keel removed after the keel was found to be moving- the keelbolts were completely corroded away. |
Example image |
Inaccessible Areas: These are the areas that almost invariably cause the surveyor his greatest problems for he can't get at them to check. Frequently, these are the areas where structural deterioration takes place because neither interior inspection or maintenance is possible.
·
Outboard and
under fuel tanks
·
Behind large
exhaust pipes and mufflers
·
Under
refrigeration and freezers
· Under shower pans
·
Under lined lockers
·
Behind hulls that
have full hull side ceilings
There's one thing you'll notice about most of the above listed areas and that is the potential for condensation and lack of air flow in these obscured areas which is highly conducive to causing deterioration of wood and metals. These obscured areas should be viewed with extreme caution. The only acceptable conclusion is guilty until proven innocent. To prove soundness, fasteners or planks must be pulled.
Failed or improperly designed fuel and water tank foundations are a common cause of catastrophic hull failure. Because of the extreme weight of tanks, if supports fail, or were never properly designed in the first place, the planking or individual frames could end bearing a major part of the tank load. When this happens, hull failure usually results.
Again, when i brought back my Grand Banks 42 from Scotland, on the journey home i remember constantly checking the fuel tanks. 4 x 300 gallon tanks full with fuel sitting on wooden stringers, now that's some weight. Be they cylindrical or square, tanks on saddles or on decks not fully supported by hull girders must be checked and the entire load bearing structure examined and evaluated. This is usually not as difficult as it might sound, for anyone with a good knowledge of proper construction can quickly size it up if the structure is accessible. If there is any doubt at all, particularly on aging structures, then other means of evaluation must be found. One of my fuel tanks is leaking slightly from underneath, the only answer is one day i will have to replace it! (major job). It will be interesting to see the hull condition once it has been removed.
Check out the following u tube clip! Not the way i will be doing it!
If the surveyor has done a good job with the interior, then his work on the bottom is going to be the easiest part of the job. By this time, he already knows if there are loose planks, bad frames, deterioration, weepage or leakage and where all these things are located. Long before it comes out of the water, he has a pretty good idea of whether this is a sound hull, and in many cases he'll already know that it isn't, so there's no point in hauling.
Nailing hulls is the common method here on the Broads. Nails cannot be pulled without causing much damage to the plank, if they can be gotten out at all. Inspecting the heads only tells one the condition of the head, not the rest of the nail. And tearing planks off means that they have to be renewed and the cost far too high. Nondestructive methods such as X-ray are both costly, difficult and not necessarily reliable.
Screw Fastened Vessels: Utilizing all the techniques outlined above, along with removal and inspection of fasteners, can provide a reasonable degree of certainty as to a hull's soundness. Moreover, screw fasteners can be replaced if they have good holding ground, meaning that planks and frames are not split or deteriorated.
To evaluate a screw-fastened bottom, first isolate the likely problem areas, including all of the garboards, under fuel tanks, and so on. One should not resort to the practice of laying out a pattern of evenly spaced points and pulling fasteners in this method as it is strictly hit or miss.
First examine for:
·
Cupped or warped
planks
·
Open seams and weepage
from interior after bottom is dry
·
Planks with split
ends or splits anywhere
·
Loose seams
·
Sound planks with
heavy hammer for sound of looseness.
·
Discoloration
around screw heads
·
Special attention
to butt ends
·
Under tanks and
engines - stress from heavy loads
·
Damp environments
like under water tanks,etc.
All of the above areas should be marked and targeted first, for it is here where the problems are likely to be. Then, if all these suspect areas prove out okay, you may not even need to pull fasteners in the non-suspect areas and this will reduce the work load greatly. The objective here is to determine whether the hull has a general condition of wasted fasteners or whether it is isolated due to the initiating factors discussed above.
Remember you need permission from the owner to pull fastenings. Tight fasteners should be hard or impossible to move. If it won't turn, don't bother trying to force it because its okay. Fasteners that just spin without backing out are bad and one needn't waste his time trying to get them out.
I will get back onto this subject of surveying wooden boats in the future, there are so many more areas left to discuss. Decks being one of them. Ive been chasing a leak on the decks on my boat for about 6 months and im still yet to find it! But hey, that's another story.
Stripping out the aft cabin on my boat- this is where you find out if you missed something! |
Lifting 'Destiny' out for the first time in Norfolk 2014. |
2015 - and finished - for now.... |
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