Folks,
The polyester gelcoat on the deck of my CD36 is badly crazed (often called "alligatoring"). This cosmetic defect extends all the way through the gelcoat to the fiberglass structure. I've already begun the gelcoat repair. However, I would like to get a some more information if possible. It has been suggested that the gelcoat crazed because it was applied too thickly. Supposedly the thick polyester gelcoat shrinks and causes the cracks and crazing, which is then exacerbated by freezing water. What I need to know is: Does the polyester shrinking mostly occur early in the life of the gelcoat and then stabilize at some point in time? Or is the rate of shrinkage constant? I'm asking because I want to make sure I'm using the best method to address the crazing. The conventional repair requires that each crack be opened to transform the crack into a small "valley" which is then filled with a resin based repair material. Most of these repairs are done with epoxy. Years of treating this problem have taught us that repairs made using more polyester gelcoat are rarely successful because the repair shrinks and what was one crack later becomes two. I'm familiar with the use of epoxy resins, and I know they shrink far less than polyesters. If you guys can tell me that the old, original gelcoat is probably through shrinking, I will be able to proceed with the repairs secure in the knowledge that the problem will stay fixed.
I need something in the repair resin to keep it where I need it to be, because the standard epoxys are all too thin and runny to stay in the valleys. I need your input about which resin thickener is best for this purpose. I have several possible additives at my disposal, and I'm familiar with using all of them. They are:
1. Q-cells, which are microscopic quartz balloons. This is an almost weightless white powder. The cured resin/Q-cell material is easy to sand and very light. The ability to easily sand this material to shape is definitely a plus, but I don't think the Q-cell has any structural value.
2. Cabosil, which is fumed silica. This additive makes the resin thixotropic and probably adds a very small amount of strength. It does NOT improve sandability.
3. Milled fiberglass fibers. These are very fine fibers which when mixed with resin and cured makes a very strong structural plastic. Compared to resin/Q-cell, it's NOT easy to sand.
4. Cotton flox. Similar to milled fiberglass. This substance makes the resin jelly-like in the uncured state. The cured mix is very strong and hard.
Any of these additives used in the proper proportion would adequately thicken the resin. I've been using Q-cell because it speeds the repair process. However, I can see the importance of having a repair substance with cured mechanical properties similar to the original gelcoat. I'm not sure about the composition of the original gelcoat. Some say it's simply polyester with pigment added. Others say it is polyester with fumed silica and pigment. Others say it probably contains a small amount of milled fiberglass as well. I'm told that epoxy resin is much stronger than polyester, so it may be as strong as the original gelcoat even with no additives. I am very interested in what the collective wisdom of this forum has to offer.
gelcoat crazing repair
Moderator: Jim Walsh
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Troy Scott
- Posts: 1470
- Joined: Jan 21st, '06, 01:23
- Location: Cape Dory 36 IMAGINE Laurel, Mississippi
gelcoat crazing repair
Regards,
Troy Scott
Troy Scott
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John Vigor
- Posts: 608
- Joined: Aug 27th, '06, 15:58
- Contact:
Epoxy paint
Troy, if you're planning to paint after you've filled the gelcoat cracks, you might want to consider Interlux's 404/414 Epoxy Primecoat as a crack-filler.
I brushed it on the cockpit and decks of a Santana 22 I once owned and it worked perfectly. It is thick enough to have some mechanical strength, but thin enough to enter and fill most cracks. It is made as a sanding undercoat and advertised as a resurfacer for cracked/crazed gelcoat--but, of course, like any epoxy, it must be painted to protect it from the sun.
I can't tell you how it stood up long-term, as I sold the boat about a year after I used the epoxy primer. But as you know, epoxy is more flexible than the original gelcoat and adheres to cured polyester gelcoat better than new polyester gelcoat would, two qualities that make it very suitable for the job.
Using this paint also meant that I didn't have to open up the gelcoat cracks as much as I might have done if I'd been tempted to use an epoxy putty.
It's possible that the original gelcoat shrinks somewhat, but I personally think the alligatoring is a combination of that and flexing. I don't think there would be continual shrinkage. The alligatoring might be exaggerated by extremes of heat and cold, however, especially if water gets in and freezes.
I have some reasonably large gelcoat cracks on my CD27 that can't be explained by anything other than shrinkage, but they haven't got worse in the years I've owned the boat. But cracks from flexing, even the smallest amount of flexing, are likely to multiply with age, because the structure of the boat is likely to get more flexible, rather than stiffer, with the years and the punishment sailing gives it.
Epoxy prime coat has the ability to flex with the gelcoat and I can't think of anything more suitable, although, as I said, I can't say how it will stand up over the years--possibly sink in or spew upward slightly, it's hard to say.
Those gelcoat cracks are on my list of jobs to do, and when that time comes I will certainly use 404/414. The trick, I guess, is to do it just before you want to sell the boat. Ahem.
Cheers
John V.
__________________________
From Vigor's Rules for Life:
7. O'Brien's Principle, or the $357.73 Theory: "Accountants reject any expenses claim with a bottom line divisible by 5 or 10."
I brushed it on the cockpit and decks of a Santana 22 I once owned and it worked perfectly. It is thick enough to have some mechanical strength, but thin enough to enter and fill most cracks. It is made as a sanding undercoat and advertised as a resurfacer for cracked/crazed gelcoat--but, of course, like any epoxy, it must be painted to protect it from the sun.
I can't tell you how it stood up long-term, as I sold the boat about a year after I used the epoxy primer. But as you know, epoxy is more flexible than the original gelcoat and adheres to cured polyester gelcoat better than new polyester gelcoat would, two qualities that make it very suitable for the job.
Using this paint also meant that I didn't have to open up the gelcoat cracks as much as I might have done if I'd been tempted to use an epoxy putty.
It's possible that the original gelcoat shrinks somewhat, but I personally think the alligatoring is a combination of that and flexing. I don't think there would be continual shrinkage. The alligatoring might be exaggerated by extremes of heat and cold, however, especially if water gets in and freezes.
I have some reasonably large gelcoat cracks on my CD27 that can't be explained by anything other than shrinkage, but they haven't got worse in the years I've owned the boat. But cracks from flexing, even the smallest amount of flexing, are likely to multiply with age, because the structure of the boat is likely to get more flexible, rather than stiffer, with the years and the punishment sailing gives it.
Epoxy prime coat has the ability to flex with the gelcoat and I can't think of anything more suitable, although, as I said, I can't say how it will stand up over the years--possibly sink in or spew upward slightly, it's hard to say.
Those gelcoat cracks are on my list of jobs to do, and when that time comes I will certainly use 404/414. The trick, I guess, is to do it just before you want to sell the boat. Ahem.
Cheers
John V.
__________________________
From Vigor's Rules for Life:
7. O'Brien's Principle, or the $357.73 Theory: "Accountants reject any expenses claim with a bottom line divisible by 5 or 10."
crazing
J V
Thanks for the tip - I too have been reading up on crazing lately and appreciate a solution .
FWIW - For the flexing as a cause I've seen/read that some go thru the trouble of reinforcing the 'glass with additional layers or by adding "stringers" below.
B2
Thanks for the tip - I too have been reading up on crazing lately and appreciate a solution .
FWIW - For the flexing as a cause I've seen/read that some go thru the trouble of reinforcing the 'glass with additional layers or by adding "stringers" below.
B2
I went through this 5 years back and it is difficult to determine which cracks would benefit from additional reinforcement and which can do without it. Just a few have recracked in a minor way and these were ones I felt at the time were insignificant and would be least likely to reappear. These areas are prone to be 90' turns, like combing to seat or cabin house side to deck. They were hairline prior to repairing them and to my chagrin hairline post repair !
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Ford Model 48 History
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Ford Model 48 History
Last edited by Ron M. on Feb 11th, '11, 05:30, edited 1 time in total.
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Troy Scott
- Posts: 1470
- Joined: Jan 21st, '06, 01:23
- Location: Cape Dory 36 IMAGINE Laurel, Mississippi
crazing repair
Earlier today I spoke with tech support at yachtpaint/Interlux. They do indeed recommend 404/414 epoxy primer for filling hairline cracks. I have thought about this a lot. I realize that Interlux is a large and experienced outfit and that their advice is not to be taken lightly. However, I still have doubts about simply filling the cracks and hoping for the best. Everything I've read about bonding tells me that it's extremely important to clean and/or clean and sand the surfaces to be bonded. These nearly 20 year old cracks have to be full of some of every substance that's ever soiled the deck. How could anyone adequately prepare the inner surfaces of these hairline cracks? How would you even know how deep the crack is if you don't open it? While I would really LOVE to believe that just forcing epoxy primer into the cracks would adequately repair them, my experience and common sense tell me this can't be a good long-term solution. Even though it will take much more time, I can't help but believe that opening up the cracks prior to filling them will ultimately be better. The bonding surfaces will be fresh. I'll be positive that I've found the bottom of each crack. I'll know that the crack is completely filled with good material.
Are there any polymers experts among us? I would still like to know for sure that the gelcoat has stopped shrinking......
Are there any polymers experts among us? I would still like to know for sure that the gelcoat has stopped shrinking......
Regards,
Troy Scott
Troy Scott
Epoxy gelcoat work tip.
One useful trick for the epoxy with fillers....after putting the material in place (whether you use a Dremel with a sharp point burr or simply try filling the existing cracks) you can put thin (low mil weight) duct tape directly onto the epoxy/deck area.
Use the corner of a wooden stir stick to push tracks into the tape, matching your non-skid pattern. The thin duct tape will bend sufficiently to get a nice finish pattern, and excess that squeezes out can be cleaned up with acetone before it cures....but dry the acetone well and quickly. The duct tape will peel up perfectly after the epoxy cures, and any residue cleans up easily. The texture left behind will be very close to old gel coat!
If you choose to use a Dremel to V out the cracks, practice on some non-visible areas (like under the locker hatches) and learn to use two hands on the Dremel with your elbows braced on some carpet (if you don't do this, your hands will not move smoothly while your elbows are braced....something about the way our body is wired!) The key is not to dig too deep or push too fast, to prevent the tip from walking with bit rotation.
Food for thought....for long straight cracks it may be better to use a short piece of hacksaw blade, held in sheet metal tongs. A 2-3" piece of blade cuts the gelcoat easily and is VERY easy to cut straight lines. I cut hacksaw blades by grinding through the side until I can bend and break the part I want. You can grind a little curve at each end, to ease the cut into the gel coat. This is a very controllable tool for critical areas. 18 to 24 point blades will work fine. You can get sheet metal tongs (Vise Grip brand is best) at most good auto parts or hardware stores. You can maintain directional control over convex curves by clamping a small C-clamp onto the back bone of the tongs....try it to see how much it helps!
You can get a nice matched finish that won't need any sanding. If you want to paint the non-skid (all of it), mix about 1 part flat white to 5 parts of your color to get a realistic gel coat appearance that doesn't show shoe marks.
Hope there's something here that'll help.
Regards, JimL (now boat-less but still on the ocean in kayaks)
Use the corner of a wooden stir stick to push tracks into the tape, matching your non-skid pattern. The thin duct tape will bend sufficiently to get a nice finish pattern, and excess that squeezes out can be cleaned up with acetone before it cures....but dry the acetone well and quickly. The duct tape will peel up perfectly after the epoxy cures, and any residue cleans up easily. The texture left behind will be very close to old gel coat!
If you choose to use a Dremel to V out the cracks, practice on some non-visible areas (like under the locker hatches) and learn to use two hands on the Dremel with your elbows braced on some carpet (if you don't do this, your hands will not move smoothly while your elbows are braced....something about the way our body is wired!) The key is not to dig too deep or push too fast, to prevent the tip from walking with bit rotation.
Food for thought....for long straight cracks it may be better to use a short piece of hacksaw blade, held in sheet metal tongs. A 2-3" piece of blade cuts the gelcoat easily and is VERY easy to cut straight lines. I cut hacksaw blades by grinding through the side until I can bend and break the part I want. You can grind a little curve at each end, to ease the cut into the gel coat. This is a very controllable tool for critical areas. 18 to 24 point blades will work fine. You can get sheet metal tongs (Vise Grip brand is best) at most good auto parts or hardware stores. You can maintain directional control over convex curves by clamping a small C-clamp onto the back bone of the tongs....try it to see how much it helps!
You can get a nice matched finish that won't need any sanding. If you want to paint the non-skid (all of it), mix about 1 part flat white to 5 parts of your color to get a realistic gel coat appearance that doesn't show shoe marks.
Hope there's something here that'll help.
Regards, JimL (now boat-less but still on the ocean in kayaks)
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Troy Scott
- Posts: 1470
- Joined: Jan 21st, '06, 01:23
- Location: Cape Dory 36 IMAGINE Laurel, Mississippi
gelcoat repair
Thanks, Jim!
This kind of information is always helpful. We've been having very good luck with this Dremel cutter:
Dremel 1/8'' Tungsten Carbide Cutter - 9910
The 9910 Features:
• High-speed cutter made of tungsten carbide.
• Ideal for shaping, smoothing or removing material from especially
hard materials including hardened steel, stainless steel, cast iron,
nonferrous metals, fired ceramics, plastics and hard woods
This cutter is tapered to a rounded point. The resulting opened crack is about 5/64ths" wide with a nice rounded bottom. I have a helper who is very good at this and patient enough to spend hours opening the cracks. I think I may need to adopt him....
An aside to anyone contemplating repair of the cracks without first opening them: Before I became the owner of my boat the non-skid was repainted, apparently in an effort to hide/cover/fill the crazing. In each case, when we open a crack, we discover that the crack is longer than was originally apparent. In NO case did the paint penetrate and fill the crack, it merely bridged over it terporarily. In comparison to a high quality deck paint, a high-build epoxy primer would probably be thicker and even less likely to penetrate down into and fill a hairline crack. A better choice might be thin penetrating epoxy resin. But I feel better just opening the cracks a filling them with a slightly thickened high quality epoxy.
Folks, does anyone have any input about the ongoing shrink rate (if any) of the gelcoat?
This kind of information is always helpful. We've been having very good luck with this Dremel cutter:
Dremel 1/8'' Tungsten Carbide Cutter - 9910
The 9910 Features:
• High-speed cutter made of tungsten carbide.
• Ideal for shaping, smoothing or removing material from especially
hard materials including hardened steel, stainless steel, cast iron,
nonferrous metals, fired ceramics, plastics and hard woods
This cutter is tapered to a rounded point. The resulting opened crack is about 5/64ths" wide with a nice rounded bottom. I have a helper who is very good at this and patient enough to spend hours opening the cracks. I think I may need to adopt him....
An aside to anyone contemplating repair of the cracks without first opening them: Before I became the owner of my boat the non-skid was repainted, apparently in an effort to hide/cover/fill the crazing. In each case, when we open a crack, we discover that the crack is longer than was originally apparent. In NO case did the paint penetrate and fill the crack, it merely bridged over it terporarily. In comparison to a high quality deck paint, a high-build epoxy primer would probably be thicker and even less likely to penetrate down into and fill a hairline crack. A better choice might be thin penetrating epoxy resin. But I feel better just opening the cracks a filling them with a slightly thickened high quality epoxy.
Folks, does anyone have any input about the ongoing shrink rate (if any) of the gelcoat?
Regards,
Troy Scott
Troy Scott
gel coat cracks
Hi All:
I have filled several gelcoat cracks in the areas of smooth gelcoat (not in the nonskid areas) by opening the crack with an old fashion pointed can opener, then filling with thickend matching gelcoat using a flexible putty knife. A light sanding with 400 and it is done. Some meticulous cleaning of the crack with acetone on rag goes without saying. Masking the area around it with tape and pulling the tape just after the gelcoat kicks makes the clean up easier.
This is quick and holds quite well, assuming the crack is just a shrinkage crack. Structural cracks are a different matter all together.
Boyd
s/v Tern
CD30 MkII
Fort Lauderdale, Fla.
I have filled several gelcoat cracks in the areas of smooth gelcoat (not in the nonskid areas) by opening the crack with an old fashion pointed can opener, then filling with thickend matching gelcoat using a flexible putty knife. A light sanding with 400 and it is done. Some meticulous cleaning of the crack with acetone on rag goes without saying. Masking the area around it with tape and pulling the tape just after the gelcoat kicks makes the clean up easier.
This is quick and holds quite well, assuming the crack is just a shrinkage crack. Structural cracks are a different matter all together.
Boyd
s/v Tern
CD30 MkII
Fort Lauderdale, Fla.
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Troy Scott
- Posts: 1470
- Joined: Jan 21st, '06, 01:23
- Location: Cape Dory 36 IMAGINE Laurel, Mississippi
Thickener
There are two options on thickening. First you can buy it already thickened. There is a vender mentioned in the Archives who sells a gelcoat match for CD's and offers it in either sprayable or thickened.
The second option is to pour about twice what you think you need in a cup and stir till its the consistency you want. Do this before you catalyze. Takes a minute or two for the styrene to flash out.
Boyd
s/vTern
CD30 MkII
Fort Lauderdale, Fla.
The second option is to pour about twice what you think you need in a cup and stir till its the consistency you want. Do this before you catalyze. Takes a minute or two for the styrene to flash out.
Boyd
s/vTern
CD30 MkII
Fort Lauderdale, Fla.
relieve the cracks
it may also be helpful to drill small holes at the ends of these cracks.
These small holes will provide a relief and stop the crack from "growing"
These small holes will provide a relief and stop the crack from "growing"
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Troy Scott
- Posts: 1470
- Joined: Jan 21st, '06, 01:23
- Location: Cape Dory 36 IMAGINE Laurel, Mississippi
different materials
Boyd,
OK. You're repairing the cracks with gelcoat. That's certainly a reasonable approach if there aren't too many cracks and the gelcoat is otherwise in good condition. It's very important to "get it right" with gelcoat; if the mix and the application procedure isn't just so the gelcoat will shrink and you'll have two cracks where there was one. Long before I became the owner of my boat, several repairs were made using gelcoat to repair cracks. In every case the repair material shrank and there are now two cracks for every one there was before. I believe that it is probably possible to do good crack/crazing/alligatoring repair using polyester gelcoat, but I don't think the long term success rate is very high. It's just too tricky to get it right.
On my deck there are MANY cracks, and the gelcoat is pretty dull and chalky. I feel the need to do a thorough fix followed by a total LPU paint job. I am using epoxy materials because they are far less likely to shrink. What I'm trying to learn from this forum is if anyone has had better of worse luck and with any one of the dry additives to the epoxy for the specific purpose of gelcoat crack repair preparatory to a total paint job, and just as important: a chance to observe the repairs over a long period of time. I'm already familiar with the use of the materials, and I've already started an experiment to see which works the best. Of course, I won't have any long term experience for a while...., that's why I'm asking. With regard to how well this works, check back with me in about 2026.
Yesterday, after many efforts, I was finally able to get some input from a composites engineer at a company that manufactures gelcoat. She told me that often manufacturers make mistakes, sometimes (but not always) because of misguided notions of production efficiency. These mistakes occasionally lead to problems with the gelcoat. However, she said, the apparent shrinking that probably caused the cracks on my Cape Dory probably occurred early in the life of the boat. She said that if any cracking occurred more recently it's probably because water froze in the pre-existing cracks and widened them. She agreed with me that if I repair the cracks using materials that won't shrink, it should stay fixed. She suggested that fumed silica which goes by the brand names Cabosil and Aerosil would be best for thickening the epoxy. This additive is usually used to give runny liquids a thixotropic (like mayonnaise) quality. It's actually found in some foods. I have used Cabosil for years, but not for boat repair. I'm once again widening my horizons.
OK. You're repairing the cracks with gelcoat. That's certainly a reasonable approach if there aren't too many cracks and the gelcoat is otherwise in good condition. It's very important to "get it right" with gelcoat; if the mix and the application procedure isn't just so the gelcoat will shrink and you'll have two cracks where there was one. Long before I became the owner of my boat, several repairs were made using gelcoat to repair cracks. In every case the repair material shrank and there are now two cracks for every one there was before. I believe that it is probably possible to do good crack/crazing/alligatoring repair using polyester gelcoat, but I don't think the long term success rate is very high. It's just too tricky to get it right.
On my deck there are MANY cracks, and the gelcoat is pretty dull and chalky. I feel the need to do a thorough fix followed by a total LPU paint job. I am using epoxy materials because they are far less likely to shrink. What I'm trying to learn from this forum is if anyone has had better of worse luck and with any one of the dry additives to the epoxy for the specific purpose of gelcoat crack repair preparatory to a total paint job, and just as important: a chance to observe the repairs over a long period of time. I'm already familiar with the use of the materials, and I've already started an experiment to see which works the best. Of course, I won't have any long term experience for a while...., that's why I'm asking. With regard to how well this works, check back with me in about 2026.
Yesterday, after many efforts, I was finally able to get some input from a composites engineer at a company that manufactures gelcoat. She told me that often manufacturers make mistakes, sometimes (but not always) because of misguided notions of production efficiency. These mistakes occasionally lead to problems with the gelcoat. However, she said, the apparent shrinking that probably caused the cracks on my Cape Dory probably occurred early in the life of the boat. She said that if any cracking occurred more recently it's probably because water froze in the pre-existing cracks and widened them. She agreed with me that if I repair the cracks using materials that won't shrink, it should stay fixed. She suggested that fumed silica which goes by the brand names Cabosil and Aerosil would be best for thickening the epoxy. This additive is usually used to give runny liquids a thixotropic (like mayonnaise) quality. It's actually found in some foods. I have used Cabosil for years, but not for boat repair. I'm once again widening my horizons.
Regards,
Troy Scott
Troy Scott
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Oswego John
- Posts: 3535
- Joined: Feb 5th, '05, 20:42
- Location: '66 Typhoon "Grace", Hull # 42, Schooner "Ontario", CD 85D Hull #1
Bondo-Marine
Troy and all,
I have to agree with J V on the use of Interlux Epoxy Primecoat on hairline and alligator cracks. It does a nice job. If you are concerned with the paint "bridging the cracks, what I do is apply the epoxy with a cheap chip brush and then, holding the brush vertical, dab the brush tip into the cracks to force any air out and total fill the crack
For what it's worth, I've had good luck using Bondo-Marine for filling hairline cracks as well as larger blemishes. I don't recommend using Bondo automotive for working on boats. They also make a marine grade for working on boats. Automotive type is comprised of a mix of polyester and gypsum, (sheetrock filler). The Bondo-Marine isn't poly, it is epoxy based.
It is a two part mix, easy to mix. Equal parts of part A and part B. It has the consistency of pancake syrup. Bondo also has a full line of powders and thickeners for use with the epoxy. I have also used the West System and it's additives, also a fine product.
As others have said earlier, preparation and cleanliness are paramount for a good job. As for the subject of shrinkage, my boat is over 35 years old and if there was any shrinkage involved, I feel it has stopped many years ago. Stress and flexing can always happen to repeat the cracking.
You show concern about the durability factor of treatments. Epoxy filler is much stronger than a poly filler. It costs more, too. I have made epoxy repairs back in the early 1990s which have never failed to date. I have used other less known brands of epoxy and find not much difference between them except price and availability.
If you would like to browse for more interesting info, type in keyword Bondo Marine.
Good luck,
O J
I have to agree with J V on the use of Interlux Epoxy Primecoat on hairline and alligator cracks. It does a nice job. If you are concerned with the paint "bridging the cracks, what I do is apply the epoxy with a cheap chip brush and then, holding the brush vertical, dab the brush tip into the cracks to force any air out and total fill the crack
For what it's worth, I've had good luck using Bondo-Marine for filling hairline cracks as well as larger blemishes. I don't recommend using Bondo automotive for working on boats. They also make a marine grade for working on boats. Automotive type is comprised of a mix of polyester and gypsum, (sheetrock filler). The Bondo-Marine isn't poly, it is epoxy based.
It is a two part mix, easy to mix. Equal parts of part A and part B. It has the consistency of pancake syrup. Bondo also has a full line of powders and thickeners for use with the epoxy. I have also used the West System and it's additives, also a fine product.
As others have said earlier, preparation and cleanliness are paramount for a good job. As for the subject of shrinkage, my boat is over 35 years old and if there was any shrinkage involved, I feel it has stopped many years ago. Stress and flexing can always happen to repeat the cracking.
You show concern about the durability factor of treatments. Epoxy filler is much stronger than a poly filler. It costs more, too. I have made epoxy repairs back in the early 1990s which have never failed to date. I have used other less known brands of epoxy and find not much difference between them except price and availability.
If you would like to browse for more interesting info, type in keyword Bondo Marine.
Good luck,
O J
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Troy Scott
- Posts: 1470
- Joined: Jan 21st, '06, 01:23
- Location: Cape Dory 36 IMAGINE Laurel, Mississippi
Bondo Marine
Thanks, John!
I hadn't previously heard of Bondo Marine. I will check it out.
I hope I haven't offended John Vigor. If any of you have had good success filling hairline cracks with the Interlux 404/414 I think that's great!
I hadn't previously heard of Bondo Marine. I will check it out.
I hope I haven't offended John Vigor. If any of you have had good success filling hairline cracks with the Interlux 404/414 I think that's great!
Regards,
Troy Scott
Troy Scott