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Benalongtime
09-16-2015, 10:42 AM
I have oil impregnated planking below the engine on my 1952 built 72ft LOA counter stern carvel built ex government fire tug. I converted her into a cruising vessel in 1988. The vessel was re engined in 1974 with a Mercedes Benz V10 which doesn't leak oil so the culprit was the original Fairbanks Morse 2 stroke which fortunately is now in a museum and not in the boat.
The vessel has been up on the hard now for over 12 months and is well dried out in readiness to sheath her in epoxy/dynel however the oil staining/impregnation is very visible externally and obviously internally. It was suggested I treat these areas inside and out with acetone over multiple times and am seeking advice on whether this is the best method to get it clean enough for the epoxy to stick. The planking is 2 inch Australian hardwood.
any suggestions from your experienced members would be very much appreciated.:confused:

wizbang 13
09-16-2015, 11:29 AM
dunno . recon it would take a lot of solvent.
I might try a regular de greaser first, then alcohol. cheaper and less toxic .
But i definitely WOULD tooth up the area like mad . I would drag a handsaw blade held in a half circle across the wood . Torture the hell out of the area. Then pre apply some epoxy with the slowest hardener.The longer it is wet , the deeper it travels in . Then sand and fill the toothed up area before laying the dynel .
bruce

Michael D. Storey
09-16-2015, 11:36 AM
Consider something like kitty litter onthe inside to suck out as much as you can, first. I do not think that alcohol disolves petroleum. There are detergents that will, however, and can be applied with hot water and then removed with a pump and disposed of

Jay Greer
09-16-2015, 11:38 AM
I published a post on this several years ago. Rather than search, I will give you the gist of it.
Go to a pool supply store and get a pound of Diatamaceous earth. This is the absorbent material that goes into pool filters. Then get a quart or two of naphtha.
Coleman fuel or white gas will work as well but naptha is best as it will dissolve the oil better. Make a paste of the powder and naptha and apply it to the oil soaked wood. Scrub with a fine brush and pile on more paste. Go get a latte and read the paper. When you are finished, the powder should be bone dry. Suck up same with a vacuum. If the oil is not removed the first time, repeat the process till the wood shows no evidence of oil.
Jay

Steamboat
09-16-2015, 11:59 AM
Consider something like kitty litter onthe inside to suck out as much as you can, first. I do not think that alcohol disolves petroleum. There are detergents that will, however, and can be applied with hot water and then removed with a pump and disposed of


I published a post on this several years ago. Rather than search, I will give you the gist of it.
Go to a pool supply store and get a pound of Diatamaceous earth. This is the absorbent material that goes into pool filters. Then get a quart or two of naphtha.
Coleman fuel or white gas will work as well but naptha is best as it will dissolve the oil better. Make a paste of the powder and naptha and apply it to the oil soaked wood. Scrub with a fine brush and pile on more paste. Go get a latte and read the paper. When you are finished, the powder should be bone dry. Suck up same with a vacuum. If the oil is not removed the first time, repeat the process till the wood shows no evidence of oil.
Jay

Alcohol would not dissolve/extract much oil from the wood. A good clay based kitty litter should pick up the gross oil before you attack with solvent or the solvent DE mix that Jay suggests. Oil does bind to clay. Any solvent that would work will be very flammable and the vapor would ignite easily with a static spark. Good ventilation is required. I am wondering if this is a situation where CPES may actually work better than standard epoxy. The solvents in CPES MAY help the epoxy get through any residual oil and into the wood. In the good old days, before we knew it was so toxic, people would use solvents like trichloroethylene or carbon tetrachloride because they dissolve oil very quickly and are not flammable. They just cause cancer and kill your liver.

wizbang 13
09-16-2015, 12:22 PM
I was thinking alcohol to clean the cleaner

willin woodworks
09-16-2015, 12:50 PM
I think no matter which method you choose to rid the planking of oil I would use CPES to prime to wood prior to applying any epoxy. Toothing the wood as Wiz describes will be essential to ensuring a good mechanical as well as a chemical bond.

Good ventilation and NO sources of accidental ignition while you're filling the bilges with a variety of flammable and explosive solvents........

jonboy
09-16-2015, 01:39 PM
A strong caustic solution will degrease just about anything except aluminium... it will work on hardwood a treat but though not toxic it is not pleasant or easy to use, and of course is a water solution so the boat's going to get well soaked as you have to rinse with tons of water too. it will undo your 12 mth drying out, but in any other situation, its the way to go ....best paint and varnish stripper too, accepting certain eco-logistical issues.

Peter Malcolm Jardine
09-16-2015, 02:25 PM
I'm left wondering why you would sheath the hull of a boat like that unless you have some deteriorating planks. The sheathing will be the death knell for the wooden structure.

Phil Y
09-16-2015, 04:34 PM
You can't post about a 72 foot converted tug without posting a massive number of pictures! It's a bit tricky, but not too bad. Put them on a hosting site, copy the URL. Click on the little box at the top of the reply panel which looks a bit like a landscape. Paste into the From URL dialogue box, and untick the check box. That's about it. On some computers you can just drag and drop, but not always.

And yes, I wonder if sheathing is a good idea at all?

Jay Greer
09-16-2015, 04:45 PM
Here are the pictures from the post I made on removing stains from teak. In this case it was a mixture of tallow and black pine tar that had been absorbed by the teak on a very hot day.
Jayhttps://im1.shutterfly.com/media/47b9db26b3127ccec75a936d9dd500000040O00QYsmrNy5bsQ e3nwg/cC/f%3D0/ls%3D00107990352120090507231733022.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/
https://im1.shutterfly.com/media/47b9db26b3127ccec75b1eb9fd9300000040O00QYsmrNy5bsQ e3nwg/cC/f%3D0/ls%3D00107990352120090507233228949.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/

Jay Greer
09-16-2015, 04:49 PM
https://im1.shutterfly.com/media/47b9db26b3127ccec75b06c67cd000000040O00QYsmrNy5bsQ e3nwg/cC/f%3D0/ls%3D00107990352120090507233510224.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/https://im1.shutterfly.com/media/47b9db26b3127ccec75a7b501cac00000040O00QYsmrNy5bsQ e3nwg/cC/f%3D0/ls%3D00107990352120090507233515879.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/

Paul Pless
09-16-2015, 07:07 PM
1952 built 72ft LOA counter stern carvel built ex government fire tug. I converted her into a cruising vessel in 1988. pics please

Jay Greer
09-16-2015, 07:27 PM
A strong caustic solution will degrease just about anything except aluminium... it will work on hardwood a treat but though not toxic it is not pleasant or easy to use, and of course is a water solution so the boat's going to get well soaked as you have to rinse with tons of water too. it will undo your 12 mth drying out, but in any other situation, its the way to go ....best paint and varnish stripper too, accepting certain eco-logistical issues.
I have to make a few comments concerning comments that others have made. Naptha is the solvent that, up until recently, was used for dry cleaning. The fluid is an excellent grease solvent. Certainly all precautions should be applied to its use as others have mentioned. The diatamatious earth absorbs the dissolved oil or grease literally sucking it out of the wood grain. All things being said, as an art conservator, I have used this system of removing oil from fabrics and wood grain for many years. I have never had it fail to work.
A caustic solution runs the risk of destroying the lignin structure of the wood unless great care is taken to neutralize it as soon as possible. In fact, I have never attempted using it,so I can't vouch for it.
Another approach that I have not actually used but, might work would be to substitute CMI saw blade degumming solution for the Naptha. The degumming solution is an excellent grease and oil solvent and should be mixed with water rather than applied full strength. If you want a non toxic grease solvent, this would certainly fill the bill. Using it in conjunction with the Diatamatious earth may or may not work as water does not evaporate as rapidly as does Naptha. So if you opt to substitute the CMI degumming product, I am sure we all would like to hear how it worked for you.
Jay

Benalongtime
09-17-2015, 10:53 AM
Wow, thanks everyone for your advice, you have all been very helpful and I am astounded at the speed and number of replies. Too many to answer each one however I will certainly mull over everyone's input.
photos yes, I will get around to posting some when I get some more time.
To those of you wondering why I would do this to a large timber vessel and yes I have pondered the same question myself,I will explain the situation.
i have owned this lovely old girl for the past 27 years and have always maintained her well both above and below the water line however I am not getting any younger, something we all share unfortunately and I am finding the slipping and below water maintenance of a timber vessel of this size increasingly difficult.
i did try and sell the vessel a few years back however nobody wants to pay a decent price for her and particularly so in today's very depressed market.
She is a wonderful and spacious live aboard which although I don't live on her all the time I may well do in the future.
She was built between 1949 and 1952 by the NSW government by very skilled shipwrights from the old country.
Post war copper was in short supply so her plank fastenings are 5/16 black iron double dipped galvanised coach head bolts countersunk with cotton caulking wound under the heads. At a good guess I would say 75% are still in good condition and there are thousands of them. The laminated spotted gum ribs ( 4 x 3 ) are at 9" to 12 " centres and with 8" x 2 1/2 " stringers she is a very stiff and solid vessel. Planking is still good with no wet planks from toredo damage although I have put gravos in here and there in some planks where worms have tried to get in. She was needing a full re caulking after all these years so after seeing 50 ft fishing trawlers that have been successfully epoxy sheathed and being in my senior years
and at times absent from the vessel for periods , I would like to lessen the worry of worm infestation should I not be able to slip her every 12 to 18 months in our sub tropical climate. Others who have sheathed timber vessels have said that if done correctly you have a vessel with the advantages of a timber boat without the hassles.
i welcome any comments on what I plan for her and I will continue this thread later. Thanks everyone :)

Jay Greer
09-17-2015, 11:37 AM
Sounds like a fine vessel to call one's home.
Jay

BrianM
09-17-2015, 12:42 PM
1974 with a Mercedes Benz V10 which doesn't leak oil so the culprit was the original Fairbanks Morse 2 stroke which fortunately is now in a museum and not in the boat.

You can't go far in the thread without posting a picture of that v10 engine.


Diesel?

MN Dave
09-18-2015, 12:27 AM
Wow! This is a sure fire (pun intended) application for a Darwin award!

The OP was asking how to clean the bilge. You know, the enclosed space where gasoline fumes, which are almost exactly like naphtha, tend to collect and blow up your boat? The strongest argument in favor of a diesel? That space, those fumes.


https://im1.shutterfly.com/media/47b9db26b3127ccec75b06c67cd000000040O00QYsmrNy5bsQ e3nwg/cC/f%3D0/ls%3D00107990352120090507233510224.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/

Doesn't anyone see the impending disaster in this picture? A highly volatile, extremely flammable solvent getting sucked up with a non-explosion proof motor and a highly effective static electricity generator. A little too much naphtha and this will kill you.


e.g (http://www.twincities.com/minnesota/ci_6152688).
http://extras.mnginteractive.com/live/media/site569/2007/0615/20070615__070616Fire_300.jpg

slug
09-18-2015, 04:01 AM
Avoid flaring off like an oil platform and use water soluble degreasers. Part A of two part teak cleaner is aggressive.

Gunk..the foaming type in a spray can is very good.

http://s28.postimg.org/5fppryx1p/image.jpg (http://postimg.org/image/cixl7l2h5/full/)
upload images free (http://postimage.org/)



brake cleaner in a spray can is also very powerful. WURTH is a brand I use

Ive not used brake cleaner on wood. Give it a try.

Steamboat
09-18-2015, 07:54 AM
Avoid flaring off like an oil platform and use water soluble degreasers. Part A of two part teak cleaner is aggressive.

Gunk..the foaming type in a spray can is very good.
brake cleaner in a spray can is also very powerful. WURTH is a brand I use
Ive not used brake cleaner on wood. Give it a try.

WURTH brake cleaner is 90+% n-heptane, one carbon atom shorter than octane. Spraying this in an enclosed space could be very exciting!

slug
09-18-2015, 08:31 AM
Normally I only use brake cleaner in the workshop. Be alert if using in a confined space...you might start flapping around like a sardine or go BOOM.

as I said...stick with water soluable degreasers. ive had good luck with spray foam GUNK brand, hot water and a wet and dry vac.

A power wash made by using a garden type pump up sprayer is very effective in bilges. It delivers a powerful jet but not so powerful that you make a big mess.

Dan McCosh
09-18-2015, 08:47 AM
Getting epoxy to "stick" to two-inch hardwood planking is probably not the issue. A structural sheathing usually is managed with mechanical fastening, not relying on adhesive bonding. Hopefully, this is not a layer of cloth applied like wall paper.

CapnJ2ds
09-18-2015, 09:08 AM
Getting epoxy to "stick" to two-inch hardwood planking is probably not the issue. A structural sheathing usually is managed with mechanical fastening, not relying on adhesive bonding. Hopefully, this is not a layer of cloth applied like wall paper.
Seconded!
If there are going to be mechanical fasteners, a few places where the sheathing doesn't stick won't matter too much in a hull this size. Oil impregnated wood is (almost) rot-proof.

FWIW, simple dishwash liquid is an excellent de-greaser/de-oiler.

Benalongtime
09-18-2015, 10:13 AM
Hi Brian, unfortunately I can't post a photo of the V10 as it's undergoing a rebuild having been in the vessel since 1974.
i am away at present but will try and dig up an older photo when I return home.
its a naturally aspirated Diesel engine of 320 hp. These were truck engines however they were not that popular with truckers due to their power to weight ratio however they are ideal for marine application. No vibration and quite economical. This one runs a 4 blade 48 " prop with 36 " pitch through a Capitol gearbox with 4.5 reduction. The V10 will only run out to about 1800 RPM in this setup but with the easily driven hull she is on the sweet spot at 1400 / 1500 RPM.
i love Gardners however I have been very impressed with this Merc.

Jay Greer
09-18-2015, 10:47 AM
A form of bilge cleaning that will afford no more hazard than those of mishandling by the operator is steam cleaning. Steam guns and pumps can be rented and used in conjunction with TSP in solution or the CMI Degumming fluid mentioned earlier. Most other systems are for surface cleaning only which is why I have offered deep cleaning solutions to your problem.
Jay

Bob Cleek
09-18-2015, 11:09 AM
Doesn't anyone see the impending disaster in this picture? A highly volatile, extremely flammable solvent getting sucked up with a non-explosion proof motor and a highly effective static electricity generator. A little too much naphtha and this will kill you.
Yes Dave, It is a formula for disaster if you don't take the proper precautions which are duly noted in the post. While we are on the subject of safety, how are the bilge blowers in your own boat working if you have a gas engine? Do you use propane on your boat? When is the last time you checked the entire system for integrity. Do you sail? How is your standing rigging doing? Have you checked all the swaged fittings lately? How about your ground tackle. Do you carry a storm anchor? Is your ground tackle marked for the amount of feet or fathoms payed out? How many anchor rodes do you have on board? How many life jackets do your carry? How many of them are for children. Is your compass swung? Do you have a local tide chart that is printed on paper? Do you have a means to climb your rig that does not depend on another crew member to assist you? Do you carry a grapnel? Do you have a dingy or life raft that will carry all persons on board? Do you have a fog horn, whistle and bell. Do you carry a copy of Chapman's that is up to date? Are your batteries gel or lead acid and are they ventilated to prevent possible gassing explosion? Are you able to steer in case of rudder damage? Would you be able to repair a broken rudder at sea? Do you have a radar reflector?
Do you have local charts or rely soely on sat nav? Do you have a licensed radio or do you use a cell phone? Can you box a compass? Do you carry a chronometer on board? Do you have a lead line? Do you have a fathometer? How many fire extinguishers do you have on board? Are they up to date? Do you carry a first aid kit and is it up to date? Do you carry a first aid manual? Do you carry storm sails? Do you have the means to set a drogue or sea anchor? Do you have a towline? Do you have a tool kit and materials that will allow you to make repairs of broken spars or a punctured hull? Do you carry code flags and can you read them? Do you know morse code? How is your reefing tackle? Do you have a Handy Billy on board? Can you tie a trucker's hitch? Can you tie a rolling hitch? Can you tie a tugboat bowline? Do you carry chafing gear and fenders? Can you back and fill in a narrow channel?
Jay

By the time I was able to answer yes to all those questions, the boat was down on her lines by three inches! :D

Bob Cleek
09-18-2015, 11:24 AM
A form of bilge cleaning that will afford no more hazard than those of mishandling by the operator is steam cleaning. Steam guns and pumps can be rented and used in conjunction with TSP in solution or the CMI Degumming fluid mentioned earlier. Most other systems are for surface cleaning only which is why I have offered deep cleaning solutions to your problem.
Jay

Another advantage of steamboats... you've always got a steam lance handy, and it can be used to repel boarders, too!

Bob Cleek
09-18-2015, 11:49 AM
First, I'll start with a disclaimer: This suggested solution is an invitation to further discussion, not a "tried and true method."

For a host of reasons, sheathing a wooden hull with any resin and fabric matrix is a bad idea. Forget all the rest and focus on the one that is of universal concern: It's a pain in the butt and expensive.

For your purposes, you are interested in preventing borer damage. The solution to that is a good bottom paint, but the poisons that made for good bottom paint are now outlawed just about everywhere. The antifouling paints now on the market don't kill marine organisms and hence are considered "eco-friendly." They are no friends to wooden boats, that's for sure!

I really think that attempting to "degrease" wood permeated with oil to the degree you describe will prove to be a fool's errand. In fact, the oil is probably doing more good for the wood at this point than anything else. There are a variety of ways to prevent borer damage. The old fashioned, and very effective way, was to paint poison on the bottom which killed the buggers when they ate it. That's' no longer an option. The other approach is a barrier to the organisms. It seems to me that treating the wood so that it is too tough for the buggers to eat is more efficient and effective than trying to put a sheath around the wood to keep them away.

Have you considered soaking the wood well with penetrating epoxy primer (Smith and Co.'s "CPES") and then applying an epoxy barrier coat as they do on fiberglass boats to prevent osmotic blistering? As flexible an epoxy as possible would be favorable, as wood does move some, but I think on balance something along those lines is going to be the only solution left to wooden boat owners now that effective biocides are unavailable. That would then be covered with as good a bottom paint as you can find these days, which will deter vegetative growth, if not borers.

Note that this isn't a substitute for maintaining the traditional caulking on a carvel planked hull. It's purpose isn't to "waterproof" the hull, but rather to provide a surface that the borers cannot eat through to get to the wood. That said, the borers will find any avenue of entry available, so very thorough application is essential.

I'd like to know if anybody has any long term experience with this approach, which I've seen some try of late. I don't know of any test data available regarding the method.

Either of these guys may have some further information on the subject: http://www.epoxyproducts.com/barrier4u.html and http://www.smithandcompany.org/CPES/

wizbang 13
09-18-2015, 12:06 PM
My boat has only resin (system 3) painted on , no cloth. 32 years old, 17 years in tropics(Caribbean).
Keeps the borers out, minimizes corrosion/electrolysis,keeps the planking stabilized(dry).
But of course she is strip planked.
I would not have a boat that stayed in the water that was not "primed/undercoated with epoxy.
(but then , I would not have a carvel boat either)

Phil Y
09-18-2015, 04:44 PM
Somewhere here is a whole bunch of threads about that Permatex rubbery truck bed swimming pool liner. I wonder if it sticks to oil too?

MN Dave
09-19-2015, 12:59 AM
Doesn't anyone see the impending disaster in this picture? A highly volatile, extremely flammable solvent getting sucked up with a non-explosion proof motor and a highly effective static electricity generator. A little too much naphtha and this will kill you.
Yes Dave, It is a formula for disaster if you don't take the proper precautions which are duly noted in the post. While we are on the subject of safety, how are the bilge blowers in your own boat working if you have a gas engine? Do you use propane on your boat? When is the last time you checked the entire system for integrity. Do you sail? How is your standing rigging doing? Have you checked all the swaged fittings lately? How about your ground tackle. Do you carry a storm anchor? Is your ground tackle marked for the amount of feet or fathoms payed out? How many anchor rodes do you have on board? How many life jackets do your carry? How many of them are for children. Is your compass swung? Do you have a local tide chart that is printed on paper? Do you have a means to climb your rig that does not depend on another crew member to assist you? Do you carry a grapnel? Do you have a dingy or life raft that will carry all persons on board? Do you have a fog horn, whistle and bell. Do you carry a copy of Chapman's that is up to date? Are your batteries gel or lead acid and are they ventilated to prevent possible gassing explosion? Are you able to steer in case of rudder damage? Would you be able to repair a broken rudder at sea? Do you have a radar reflector?
Do you have local charts or rely soely on sat nav? Do you have a licensed radio or do you use a cell phone? Can you box a compass? Do you carry a chronometer on board? Do you have a lead line? Do you have a fathometer? How many fire extinguishers do you have on board? Are they up to date? Do you carry a first aid kit and is it up to date? Do you carry a first aid manual? Do you carry storm sails? Do you have the means to set a drogue or sea anchor? Do you have a towline? Do you have a tool kit and materials that will allow you to make repairs of broken spars or a punctured hull? Do you carry code flags and can you read them? Do you know morse code? How is your reefing tackle? Do you have a Handy Billy on board? Can you tie a trucker's hitch? Can you tie a rolling hitch? Can you tie a tugboat bowline? Do you carry chafing gear and fenders? Can you back and fill in a narrow channel?
Jay
No, I don't have a bilge blower in my Gypsy.

These postings go out to the whole big, ignorant unwashed world. When you recommend doing something as potentially disastrous as this, someone out there will try it without taking all your heretofore unmentioned precautions. You are not talking to just the OP. I was talking to the guy who will see this five years from now who fills his gas tank with the motor running and a cigarette in his mouth. Not that he would necessarily be missed. For all your blethers about safety equipment, you still sucked a bunch of naphtha laden fullers earth into a closed container. Did you mention that it could blow up next time you turned it on if you didn't empty it right away?

Benalongtime
09-19-2015, 08:18 AM
Thanks Jay, I will definitely look into steam cleaning both internally and externally.

Jay Greer
09-19-2015, 01:45 PM
Actually, I did something here that I find to be irritating, when done by other posters when I answered with the naphtha and filter powder suggestion. I failed to read the entire posting and suggetions from others! I actually am often amazed by how many individuals are so interested in getting something down in print that they fail to consider all of the possibilities involved with someone following their suggestions whithout considering the possibility of creating problems. I for one, I am guilty of that in spades on this post! I was in a hurry and posted information on a sure manner of removeing oil from teak decks that has always worked for me very well. And, I deserved all of the flack that came back as a result there to! I pray and trust that no one of you will ever attempt to use naptha in such a manner as to clean up oil soaked wood below decks unless you are wearing a chemical filtration mask or a rebreather. In addition, any such practice should be done in an extremely wide open area that has directed air from a non sparking power source as mentioned by Dave. Using a volital explosive solution in a confined space is EXTREMELY DANGEROUS and can result in explosion, injury or loss of life. So, don't do it unless you are doing it outside and then in a safe manner away from any possible. source of ignition. There are many things that we do in life that are dangerous and can result in all manner of negative results. I for one have worked with such materials so long that I forgot that some one not familiar with such things might take my suggestion and create a monster! My appoligies to you all for my lack of insite that was a result of doing something in haste!


I do stand by my suggestion of either renting a rig or hiring a bilge steam cleaning service to relieve you of the absorbed oil and dirt accumulation you are dealing with. Most of the services use TSP in solution or an industrial detergent, that is EPA approved, as an aid to dissolving the oil. Many such services have a barge that can pull along side of a boat to service the cleaning in the water. They also have trucks for land service here in California. In addition, they have storage tanks for the grey water they produce and dispose of it properly. A service may be a simpler means of accomplishing your cleanup rather than doing it yourself.

Jay, The guy with egg on his face!

Jay Greer
09-19-2015, 02:02 PM
Dave posted a picture of a boat explosion that kind of tells it all! I would like to add a first hand personal experieriance here to back up his post. Many years ago, we were on our way to racing the Alden schooner "Wanderlure II" in Channel Islands Harbour in Oxnard CA and had stopped in Marina Del Rey to pick up some supplies. As we headed out for the entrance, exit channel we passed a fuel dock that was several hundred yards to weather of us. A medium sized power cruiser had just finished fueling and was preparing to leave the dock. None of us was paying much attention as this is a common scene in most marinas. But there was a flash of orange light and we all turned to see what the source was. The boat was a gasoline powered vessel and had failed to run her bilge blowers to clear out any fuel vapors. As a result there was a tremendous explosion! It was so powerful that it lifted up the entire cockpit deck and threw passengers into the water like ten pins in a bowling alley. This was followed by a powerful "Whump" and an air blast of concussion. The boat was aflame and we had no way for us to offer assistance to anyone in need of help as the Harbor Dept was already bearing down on the area full tilt and the area was crowded with other vessels. We later found that, in spite of the blast, no one had been seriously injured which was amazing for the damage that had occurred.
Jay

MN Dave
09-20-2015, 10:19 AM
I didn't want to hijack the thread, but I felt that something should be said.

I have my reservations about the use of Dynel for anything but non-skid on decks. Remember that I sail a Bolger Gypsy, and therefore I am not a member of the club that endows one with actual personal experience. I am just a M&P guy.

Dynel is a piled yarn loosely woven polyester that is not very strong or stiff. This is not to criticize Dynel, but to explain why folks say it drinks up an awful lot of epoxy. It is a low density bulky material that takes a lot of epoxy to fill the spaces between the weave. The fibers weigh half as much as glass, so 4oz Dynel has the same fiber volume as 8 oz glass. On top of that, the yarn is fluffed up, making for more air space to fill with epoxy. If you want a rough surface for a non-slippery deck, all this is to your advantage. If you want a strong, stiff, economical use of structural material, you use satin weave or biaxial glass cloth.

Dynel is not as stiff as glass. If you use West, use G-flex. MAS is also less brittle than regular West. The rest, who knows? That is not a rhetorical question. It would be very nice to have some real information.

As for sheathing with Dynel to prevent worms, it might work on the worms, but I think the planks will work and crack the sheathing along the seams. You might be better off with Sanitred. (http://sanitred.com/permaflex-waterproofing-coating-description/)
There has been a lot of criticism of Sdowney's idea, but if you read his postings, he did a lot of prep work and his method is thought out pretty well. See the last link below for a start.

I have read enough to form the semi-informed opinion that sheathing a carvel planked hull is only a good idea when the fiberglass is thick enough to be structurally significant and the interior is kept dry. It can add some years and weight to an old hull that is on its way out and not worth the expense of a full rebuild. Lots of opinions as to how many years and how much cost. I am convinced that if it is not done well enough, it is a disaster. One of the things that seems to be part of doing a proper job is mechanically fastening the fiberglass to the hull. That is most likely because you can never get adequate adhesion to an older hull, oil impregnated or not.

https://www.google.com/search?q=site%3Ahttp%3A%2F%2Fforum.woodenboat.com% 2F+veritas&ie=utf-8&oe=utf-8#q=site:http:%2F%2Fforum.woodenboat.com%2F+sheath ing+fiberglass
http://www.tis-gdv.de/tis_e/misc/holzart.htm
https://www.google.com/search?q=spotted+gum+wood&ie=utf-8&oe=utf-8#q=spotted+gum+wood+teredo
http://forum.woodenboat.com/showthread.php?11139-Building-for-Tropical-Climates-best-method-to-withstand-environment
Sheathing below the waterline is somewhat controversial here. http://forum.woodenboat.com/archive/index.php/t-118700.html

Canoeyawl
09-20-2015, 01:08 PM
I should mention that in the "old days" it was (sort of) common practice for work boats to just drain the oil into the bilge and pump it out with the bilge pump, with the thinking that the oil would preserve the planking. I have made a lifetime study of old boats, especially those found abandoned on the beach or grounded up a river on a spring flood, and with power boats often all you find is an oval shaped pallet, what is left of the frames and planking under the engine, the rest of the vessel being long gone. Used motor oil is tenacious stuff, loaded with heavy metals and I don't think you will ever get it all out of the wood, no matter what method is used.

Not so long ago you could buy "bilge cleaner" that was designed to add to the bilge and pump overboard after a few days sloshing around. (Probably TSP)

(One summer not so long ago I was moored in Bass Harbor, Maine and under cover of darkness someone did exactly that- drained the engine oil into the bilge and pumped it into the harbor on an outgoing tide. Every boat in the harbor had a black boot top... Impossible to clean it off as the bottom paint was permanently stained, I was forced to sand it off and repaint. I knew who it was, and I felt sorry for him, an ancient and starving lobster man with a boat he could barely keep afloat. He wasn't long for this world and I just moved on to another harbor.)