TOPIC: transom repair/ dry rot // penterating epoxy ??

My question is. Has anyone had experience with penetrating epoxy on a transom? my transom was initally very spongy about 4 year's ago but as I worked on the rest of the boat I kept the boat dry now the transom seems to have dried real well and is not that soft anymore.
I keep getting advice from different manufactures Now I am confused
So I would like to ask for some real help from user's of penterating epoxy.
Thank's b4 hand
Sabot (wayne)

Haven't used it on a transom but I did use Git Rot on the engine mounting bunks in an 86 Galaxie. After doing a lot of Git Rot injections, I filled the mount holes with a 2 part filler, Kitty Hair, had a lot of fibers in it. After curing I redrilled the mount holes and used new lag bolts. The repair lasted for years. Git Rot was a bit expensive considering the amount it took to saturate the bunks but for me it did the job.

Thank's
any one else out there has any experience using penatrating epoxy
All help any way shape or form is appreciated
Sabot

Your boat needs a new transom.

Penetrating Epoxy is excellent stuff, I have a couple cans on hand to pre-treat new wood for sealing out moisture. The stuff is capable of wicking into punky wood and hardening it up a bit. It does this by displacing some of the voids in the wood fibers, and bonding some of the fibers together. While this would be completely acceptable on a fascia board of a vintage home, it is far from adequate on a boat transom. The transom of an outboard boat has to be incredibly strong to do it's job without becoming fatigued. Transoms must withstand constant loads imposed by the weight and power of the motor. These forces cause the transom to flex ever so slightly when the structure is in good shape. You can't see it by looking at it - but it is indeed flexing some under all of the stress. Old partially rotted transom cores no longer have the integrity to withstand these loads. They flex readily, and can easily be seen "moving and grooving" when power is applied to the motor. Some move so much that the fiberglass cracks where it meets the splashwell. There is no way put enough rigidity back into that old transom with Epoxy. Your only intelligent choice is to tear out that transom and replace every inch of it with fresh material. I have met many people that did not replace the transom in their boat when restoring it. They thought it looked "good". It felt strong, or it sounded good when tapping on it. Every one of them regretted it, because after a season or two of use, the transoms were all failing. But how can this be, if they transom "checked out"? It's because the boat likely sat for years and years with no use. The transom "felt or looked good" because the boat had not been in the water for years. The transom had not been strained. So.. it looked fine, while deep inside of it was a rotted core. Weakness from that rot only showed up after putting the boat back into use. Please do yourself a huge favor, tear that baby out and do it right. You will be thankful you did.

sabot,

ImVho, Bruce Gerard is 100% CORRECT.

Even IF you could (which I seriously doubt) do a GOOD/longlasting repair on a weak transom with penetrating epoxy, it would cost a LOT more than "popping off the deck" and tearing out the "rotted" to the bare hull and replacing ALL of the wood with plywood "buttered with" polyester resin OR (my preference) with cheap/"generic" epoxy resin. = Doing it "the right way" is also the BEST way, imVho.

Such a through re-building will likely outlast everyone who is reading this forum!!!

yours, satx

Yeh I guess I am trying to go the easy way out since Im 74 and don't have the muscle that I once did.And obama say's that there is no cost of living increase so no more money. Yeh right, we pay his food and gas bill's
A friend of mine did his Performer as you suggested, him and his daughter together it took them 6 week's and a lot of money
I guess I can start on it before winter hit's in North Idaho.

sabot,

NOT only am I 67YY (and fairly "beat up" from too many years as an Army MP) but I'm known here I fear as "the friendly neighborhood cheapskate", so I don't spend $$$$$$$$$ on re-modeling boats. = I use MDO or T-111 instead of marine plywood, "cheap"/crude/generic epoxy instead of "name brands". "agricultural"/pulverized lime instead of commercial fillers & "remnants" of indoor/outdoor carpet instead of the "expensive stuff" from marine supply dealers.

And I prefer 1955-69 cheap/tough/over-engineered/easy to work on "BigTwin" Johnnyrudes to "generally expensive & hard to work on" Mercury OBs OR new/modern OBs, as I'm NOT a "mechanic".
(I've NEVER bought a NEW boat or OB!)

ImVho, this doesn't HAVE to be "an expensive hobby" OR a PITA to do, though it's NOT a way to "get rich" OR (generally) to "make a living". - I often get "bargains" by carefully/daily watching "salvage sites", auctions & craigslist.
(For example, I once found 12 gallons of epoxy for the princely sum of 100.oo cash on craigslist, when I lived in Baltimore. On another occasion, I was given 4 sheets of 4x8 exterior plywood "to move it, today".)

BEST WISHES on your project, satx

My Winner had no rot but the top of the transom only had an aluminum top trim piece to keep out water. Upon taking it off The top layers of plywood were delaminated but no rot. I took a hacksaw blade and determined it only extended about 5 inches. I got a GOOD waterproof wood glue and forced it down in between the layers and clamped it down. Honestly you cannot tell it was done. I then put a few layers of glass oner the top before putting trim back on.

OK guys
Here's what I have done The boat is a 1961` Admiral cabin crusier 17'4"
and is powered by a 1966 Homelite 55 Gran prix.
When I got the boat in 2000 it was a mess the po's wife had taken a axe to the whole cabin top bow to stern all windows took me 3year's as we have short summer's here in N. Idaho.
Ok now all the cabin and window's are done/the hull and upper top deck are one piece/fiberglassed together at the factory. So I just can't see distroying the intregitery of the hull to upper deck by cutting as the rear of the transom is connected to the top deck.
the transom is also supported with 1/4 " angle iron that is cut to fit over where the motor sits on it then the other portion goes across the outside of the transom
The reason for this was the boat was used in Flordia then found it's was up the Missisippi for about 6 year's then to Oregon where it spent 15 year's there in the Ocean and wound up here in n.Idaho
sitting in a farmer's field Also it had A Big Johnson V4 or 6 hanging on the transom/ which I left with the Farmer as I love my Homelite motor's. so maybe that's why the angle iron. as the transom does not seem to flex.
P.S. I am going to New Mexico to pick up a 1961 Admiral 17'4" runabout that was purchased in New York but is badged Admiral Tampa Flordia Now how cool is that 2 Admiral's The runnabout is all papered and titled from the original owner.on a 1961 gator trailer.
Sabot

Two Admirals is very cool.

sabot,

LUCKY YOU to have found suitable Homelite 55 OBs. = I've tried for 2 years to find a matched pair of Homelite "long-foots" for a 1965 deep/wide/HEAVY-built 17ft Glassic, that I have "squirreled away" on a friend's farm, with ZERO luck.
(The stripped hull weighs over 950 pounds!)

yours, satx

Hello Fellow 67er's-
This won't be long as emailing me is better for details. After restoring a 34' 1950 and a 36' 1954 Chris-Craft these little ones are easy. I use Smiths CPES on EVERY piece of wood used and if the wood is bad I replace it entirely - I only do things once. Smiths also offers a laminating resin epoxy as polyester resin is cured after 10 days and additional fiberglass will not bond chemically correct. ALWAYS USE EPOXY FOR FIBERGLASS LAYUP never polyester.

Bruce
Resident Luddite

fallsman, why not polyester? I don't get the reasoning for not using it. thanks. greg

Hi Greg-
Polyester resin is catalyzed with a cure time of about 10 days. When the amine blush (tackiness) is gone additional resin will not bond chemically anymore. Their laminating epoxy solves this. I saw a boat man install bait tanks that came "unbonded" in use with polyester resin. For more info including CPES for wood service go here: www.smithandcompany.org/LayupLaminating/

Bruce
Luddite in Residence

frog,

polyester bonds FINE with fiberglass mat/tape/fabric, etc. but does NOT bond well over the long haul with wood/plywood. - BUT epoxy does bond to glass/wood/plywood & lasts about as long as the hull does.
(For that single reason, I used the cheap/generic epoxy, thickened/unthickened for everything.)

yours, satx

So what is the chemical bonding process for polyester over old cured polyester I know body shops do it all the time because it's cheap.(disclaimer:BTW I'm not related to steve of Smiths CPES)

There is no such thing as "dry rot"

Andreas

Amine Blush only occurs with epoxy resin , it has nothing to do with polyester resins tackiness . Polyester bonds very well to wood , anyone who has ever restored one of these 40 to 50 year old boats know how hard it is to deconstruct them and to remove the dry 40 year old wood from 40 year old polyester resin .

Andreas: Semantically you're correct. It's generic term because the wood appears to be dry when in fact spores that thrive creating rot exist best in wood with a 30% moisture content. That's why mahogany and teak with their natural oils inhibit rot as moisture has difficulty penetrating.

Polyester is the worst choice you could make. "Polyester resin is the cheapest form of resin available currently to the industry and gives the poorest adhesion (as compared to Vinyl Ester and Epoxy resins). Polyester resin possesses the highest water absorption with also the highest shrinkage when laminating. Polyester resin is generally only suitable with fibreglass fibres and is best suited to building items that are not weight sensitive. Polyester resins suffer from osmotic blistering when untreated by an epoxy resin barrier to water for boats immersed permanently." www.compositepackaging.org/cs_resins.htm
Why not do the job the best you can? If cost is a factor boats are the wrong hobby.

Argument for arguments sake and me w/out my popcorn smiley.....

So gelcoat is then also the worst choice as final finish on a boat?

Accurate facts do not ALWAYS lead to correct conclusions.

Good luck gentlemen, I doubt there will be any converts to epoxy or to polyester.

.

Falls Man wrote:

Polyester is the worst choice you could make. "Polyester resin is the cheapest form of resin available currently to the industry and gives the poorest adhesion (as compared to Vinyl Ester and Epoxy resins). Polyester resin possesses the highest water absorption with also the highest shrinkage when laminating. Polyester resin is generally only suitable with fibreglass fibres and is best suited to building items that are not weight sensitive. Polyester resins suffer from osmotic blistering when untreated by an epoxy resin barrier to water for boats immersed permanently." www.compositepackaging.org/cs_resins.htm
Why not do the job the best you can? If cost is a factor boats are the wrong hobby.

Thats straight from a epoxy suppliers web site who wants to push their product lol . Im still curious about polyester having amine blush ?

HMMM Perhaps I should not be dabbling in your hobby. Hang around here and you will see that there is more than one way to skin a cat.

Robert, I hear you, im in the wrong hobby also, so maybe i'll take up knitting. (like h#ll I will) frog

Frog....that's with a "k", knitting.

thanxs kal, I fixet it. now I c0n nat evin speel, anymore. lol frog

I'm still looking on a different way to skin that damn cat too. I don't knit but I did get a brandie new sewing machine for $5.00 at a yard sale that was never opened I'm learning to use. It's a Brother.

Frog, that's worth a karma point

Robert-lorigan,

I'd bet that if you fell into the outhouse, that you'd find a 10 carat diamond too. = CHUCKLE.

yours, satx

I had to rip out the entire transom and air box on my Flyer as it was all rotted and demolished from the PO running a Johnson 75 on it. I replaced the transom with a mahogany plank and restored the air boxes with embalmed marine plywood and mahogany supports all coated with CPES and fiberglass laminated with laminating epoxy for wood.

Yes gil_72gt-160, it is straight from their website. I don't use their stuff but they explained it most succinctly. Any catalyzed epoxy will work though I prefer those formulated for use on fiberglass/wood.

Don't laugh I'm 55 years old and we used to dig holes for my friends Dad's Shithouse every few years. Right now in my community there is one "Shithouse"left standing. My Dad and I have excavated a number of them and have recovered some nice artifacts. I know of two I' planning on digging up some day where I hunt. The farm has not been there in over 70 years. I dug up a cup at the old spring several years ago. I spotted the shine where two bucks had been fighting. The leaves were turned over.

Falls Man wrote:

Yes gil_72gt-160, it is straight from their website. I don't use their stuff but they explained it most succinctly. Any catalyzed epoxy will work though I prefer those formulated for use on fiberglass/wood.

Just wondering if you'd mind sharing with us your Experience in the Resin and Fiberglass industry. On an open forum such as this it's always nice to know who's giving out advice. Are you quoting what you have read or what you know from years of use and experience. If experience how much do you have and with how many boats and or restorations. I have a very good friend that is a Factory Rep for one of the Worlds Largest Manufacturers of Epoxy and Polyester resins. He also is called to testify in court cases where catastrophic failures of resin layups has caused serious damage and or injury. He's recognized as one of the leading experts in his field. I trust him without pause. He assures me that CPES is pretty much worthless and that anytime you use solvents to thin any resin it seriously damages it's chemical/molecular properties in all areas and that it should be avoided at all costs. He has the laboratory research to back it up. At best it's a basic wood sealer but that's it. He freely admits that epoxy is a better adhesive and has better water repellant properties but Polyester's properties in these areas are MORE than adequate for small boat building and will do a more than adequate job. In All my experience working with polyester resin and boats I've never had an issue with properly prepared wood and poly resin ever delaminating or coming "undone" or having water resistance issues. Since epoxy is generally double the cost of poly and sometimes more, I can personally see no reason to go to the added expense of using it. If you prepare the old glass and wood properly, the new poly will adhere to it just fine. But just like you, that's my opinion but it is based on some pretty good facts as presented to me by an expert in the Field

Sorry MyFlamiingo for not getting back sooner-I was on the east coast: I grew up in Paul Larson's town (Little Falls) who developed the chopper gun under Rand contract and worked in it used it until I moved up to mahogany. There may be older FG mfgr's out there but not many who remember "armorglass" or it's use on boats. I even built a FG cab for a '54 Jeep. It sounds like you have a valuable resource in your friend and I agree with his view that diluting anything reduces it's effectiveness but I don't know how CPES is made as it's proprietary-maybe he guessed?? I lived in a wood boat and a half mile out in the Pacific it's 700+ ft deep. Adequate is not in my vocabulary so polyester is automatically out. If cost is an issue boats are the wrong game. Although I grew up on the Mississippi where losing a boat meant it went over the dam in spring floods, sinking really wasn't an issue, you'd get stick on a sandbar. My views/advice is worth exactly it's cost here.