Bottom Painting, Barrier Coat?
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Bottom Painting, Barrier Coat?
I know this topic has been here a few times but none of them answered my question. It's spring and it's time I removed that old hard bottom paint. I am using a chemical remover, Peel-Away. I tried a small area and it seems to work well as long as temp's are above 60. Question, I will be finishing with VC17m, so is a barrier coat like InterProtect 2000E or VC Tar recommended? This job is huge and I certianly don't want to do anymore work than is neccesary, however I want to do a job that lasts.
Stef
Odyssey #146
Odyssey #146
bottom paint
I had no luck with Peel-away and ended up having the bottom sanded and repainted professionally. They found no blisters but recommended putting on the interprotect 2000 and couldn't understand why anyone would still be using VC tar. Anyway, my experience is that the VC-17m is so thin that it's good to add the barrier coat. I've since sanded off the VC-17m -- which came off very easily, and put on VC-offshore. Again, I'm glad there's the barrier coat.
Jim Kloss
s/v Ambivalence
S2 7.9 #8
Jim Kloss
s/v Ambivalence
S2 7.9 #8
Barrier coat
Stef,
If you are stripping the bottom, that is a good time to apply a barrier coat. I have worked with the Interprotect 2000 and the west epoxy and I think they both worked well. I would not use VC Tar - my boat was coated with VC tar and it offered no protection and made it impossible to sand without clogging the sand paper immediately. I used the west system for the smaller jobs like the keel and the rudder because you could mix it in appropriate quantities but for the hull, the Interprotect is the only way to go. I had some blisteres in the boot stripe so when I did the barrier coat I did to the top of the boot strip and then applied the boot strip over the coating.
As long as you meet the recoat times you do not need to do any prep in between coats. It rolls on pretty easy and provides a nice durable coating. The only down side is it leaves a pretty rough orange peel on the surface that will need to be sanded off.
When I did my boat I had a fair number of very small dry blisters that I ground out and repaired using west filler. Following the reapir I sanded and longboarded the entire hull. After the barrier coating (6 coats) I long boarded the hull again. If you are going to long board it is worth purchasing the right tools. 3M makes really nice long boards with velcro fasteners and you can buy velcro backed sand paper.
VC-17M will work nice in fresh water and it will prevent build up so you will never need to strip the hull again.
Good luck
If you are stripping the bottom, that is a good time to apply a barrier coat. I have worked with the Interprotect 2000 and the west epoxy and I think they both worked well. I would not use VC Tar - my boat was coated with VC tar and it offered no protection and made it impossible to sand without clogging the sand paper immediately. I used the west system for the smaller jobs like the keel and the rudder because you could mix it in appropriate quantities but for the hull, the Interprotect is the only way to go. I had some blisteres in the boot stripe so when I did the barrier coat I did to the top of the boot strip and then applied the boot strip over the coating.
As long as you meet the recoat times you do not need to do any prep in between coats. It rolls on pretty easy and provides a nice durable coating. The only down side is it leaves a pretty rough orange peel on the surface that will need to be sanded off.
When I did my boat I had a fair number of very small dry blisters that I ground out and repaired using west filler. Following the reapir I sanded and longboarded the entire hull. After the barrier coating (6 coats) I long boarded the hull again. If you are going to long board it is worth purchasing the right tools. 3M makes really nice long boards with velcro fasteners and you can buy velcro backed sand paper.
VC-17M will work nice in fresh water and it will prevent build up so you will never need to strip the hull again.
Good luck
Last season I had to repair my rudder and also had a problem with the keel. Repaired the rudder over the winter and pulled the keel in April and replaced the wear shims at the top end. The keel was coming up crooked and I wasn't able to pin it. I took advatage since it was out and removed ALL paint and coatings on both, then used interprotect 2000E prior to VC 17m. You are correct, if you get the correct time between coatings no sanding required. I was however disappionted with the finish prior to VC 17m, as you said it's pretty orange peeled. However if you wait the correct time you get a chemical bond between the barrier coat and the VC 17m, I got this information directly from Interlux. Would you recommend sanding the barrier coat or go for the chemical bond and sand the VC? Being that the VC is so thin I'd be affriad of exposing the barrier coat. How many coats of the interprotect and how many quarts?
Stef
Odyssey #146
Odyssey #146
Bottom finish
I don't beleive the VC-17 forms a chemical bond with the Interprotect, I believe that bond occurs when you are applying hard bottom paints. I would tend to sand and get the bottom as smooth as possible. From my experience the smooth bottom is less porous and easier to clean. Also you are in fresh water so you are not really battling anything hard you are looking for protection from slime so for you the bottom paint is not as critical as for a boat in salt water.
When I did my bottom I applied six coats of interprotect and as I said I covered up to the top of the boot stripe. It has been a few years but as I recall when I did by initial application of VC-17 I used 5 quarts. Now I just touch up the spots that wear through each season.
When I did my bottom I applied six coats of interprotect and as I said I covered up to the top of the boot stripe. It has been a few years but as I recall when I did by initial application of VC-17 I used 5 quarts. Now I just touch up the spots that wear through each season.
A few comments on this….
Agree with what has been said about VC Tar – do not waste your time; Inter protect 2000 is a vastly superior product.
From a racing standpoint, assuming you are in fresh water I would suggest a minimum of three coats, four is you feel so inclined. Keep in mind most of Interluxx technical specs are more focused on increasing the use of more Interluxx products in greater quantities, thus increasing sales.
After you have applied your final barrier coat wait until it is fully cured. After that point you should board sand (long board works best) the entire hull – If you use a 220 grit you can sand fairly lightly and quickly. All you are looking to do is to remove the orange peel.
Once the sanding is complete use a tack cloth to wipe the whole area clean.
When you apply your VC 17 (awesome product) use a 5mm lint free roller. Only put enough VC in your tray to charge the roller and always keep the lid on the can at all times as the stuff will evaporate fairly quickly. For your first VC application I would suggest going with two coats – as everyone knows who has worked with the stuff, it dries very quickly.
Do not bother to sand it. You use some crumpled up newspaper to “burnish†the hull – the newspaper will smooth out the VC 17 finish and you are good to go.
Do not forget to use Starbrite Teflon Polish on the topsides for a complete finish.
Enjoy !
Agree with what has been said about VC Tar – do not waste your time; Inter protect 2000 is a vastly superior product.
From a racing standpoint, assuming you are in fresh water I would suggest a minimum of three coats, four is you feel so inclined. Keep in mind most of Interluxx technical specs are more focused on increasing the use of more Interluxx products in greater quantities, thus increasing sales.
After you have applied your final barrier coat wait until it is fully cured. After that point you should board sand (long board works best) the entire hull – If you use a 220 grit you can sand fairly lightly and quickly. All you are looking to do is to remove the orange peel.
Once the sanding is complete use a tack cloth to wipe the whole area clean.
When you apply your VC 17 (awesome product) use a 5mm lint free roller. Only put enough VC in your tray to charge the roller and always keep the lid on the can at all times as the stuff will evaporate fairly quickly. For your first VC application I would suggest going with two coats – as everyone knows who has worked with the stuff, it dries very quickly.
Do not bother to sand it. You use some crumpled up newspaper to “burnish†the hull – the newspaper will smooth out the VC 17 finish and you are good to go.
Do not forget to use Starbrite Teflon Polish on the topsides for a complete finish.
Enjoy !
Check your quantities
Stef,
If memory serves me - the actual quantity of VC-17m in the can is .75 quart not 1 quart so when you calcualte your coverage you need five cans to get 4 quarts.
If memory serves me - the actual quantity of VC-17m in the can is .75 quart not 1 quart so when you calcualte your coverage you need five cans to get 4 quarts.
Inetrlux 2000E interprotect saga.
Well, a good part of the season has past. Last week a went under the boat to scrub it clean for a race, not much build up but found some bubbles (1/4"-3/8"dia) in the paint. I didn't have this problem with the old saltwater antifouling and it's limited to the paint only. After speaking to a fellow racer he says he had the same problem with his J24 last year. Interlux told him he didn't put the barrier coat on thick enough. He ended up breaking all the blisters and filling them with epoxy, then recoat with more interprotect. This seems to be a common problem according to some of my other club members. One even said he had better luck with VC Tar. I used 2 gallons of Interprotect 2000E, which seemed to be 6 coats applied with a roller.
Any input/advice would be appreciated.
Well, a good part of the season has past. Last week a went under the boat to scrub it clean for a race, not much build up but found some bubbles (1/4"-3/8"dia) in the paint. I didn't have this problem with the old saltwater antifouling and it's limited to the paint only. After speaking to a fellow racer he says he had the same problem with his J24 last year. Interlux told him he didn't put the barrier coat on thick enough. He ended up breaking all the blisters and filling them with epoxy, then recoat with more interprotect. This seems to be a common problem according to some of my other club members. One even said he had better luck with VC Tar. I used 2 gallons of Interprotect 2000E, which seemed to be 6 coats applied with a roller.
Any input/advice would be appreciated.
Stef
Odyssey #146
Odyssey #146
Blisters
When I redid my bottom I was warned about making sure to wait long enough between coats. If you try to recoat too soon it can trap solvent between the layers and cause blisters like you described.
I don't think it is a big deal other than the inconvenience of having to fix it. I don't think it has anything to do with the VC-17.
I would just gind it out and fix it with West System this winter.
I don't think it is a big deal other than the inconvenience of having to fix it. I don't think it has anything to do with the VC-17.
I would just gind it out and fix it with West System this winter.
moisture, etc
I have refrained from posting on this issue for fear of offending or dissappointing those who have already done the work BUT, I must now chime in to hopefully put an end to hearty speculation and the insuing repeated blisters or NEW BLISTERS that will result.
First: there's no such thing as "waterproof". Read the stats on all epoxies and it clearly shows how much moisture each will absorb in a static test.
Second: it matters not a whit what brand, type or how many coats of bottom paint are applied. Water goes through all of them with ease.
Third and most important: If your boat has been in the water for years with no problems and you AREN'T moving the boat to a new location consider yourself lucky AND leave well enough alone. Whether or not your boat has blisters on it the gelcoat and glass still have some moisture in them. If you put barrior coat over this you are all but guaranteeing that you will develope blisters in the future, I have seen it happen time and again. If you insist on appling a barrior coat to an seemingly unblemished bottom, pull the boat out in the spring and let it bake on the trailor, preferably on a hot asphault parking lot, all summer. This is still no guarantee that the bottom is totally dry but it's about as good as you are going to get.
As far as waiting between coats goes, let your nose be the guide no matter what it says on the paint can. If you are still getting strong xylene fumes from the previous coat, WAIT! Like one of the posters said, trapping the sovents between the layers is a no-no! Rushing things just to get all of it done in one day will leave you very mad and frustrated when it blisters on you again, shortly after relaunch.
Just in case anyone thinks that I'm full of it, I have been building and repairing boats since 1975, as well as building and repairing sails since 1983. I have seen many mistakes and made more than a few and I try to never make the same one twice. Rushing any job on anything because you want to get it done is a recipe for disaster.
Dave
First: there's no such thing as "waterproof". Read the stats on all epoxies and it clearly shows how much moisture each will absorb in a static test.
Second: it matters not a whit what brand, type or how many coats of bottom paint are applied. Water goes through all of them with ease.
Third and most important: If your boat has been in the water for years with no problems and you AREN'T moving the boat to a new location consider yourself lucky AND leave well enough alone. Whether or not your boat has blisters on it the gelcoat and glass still have some moisture in them. If you put barrior coat over this you are all but guaranteeing that you will develope blisters in the future, I have seen it happen time and again. If you insist on appling a barrior coat to an seemingly unblemished bottom, pull the boat out in the spring and let it bake on the trailor, preferably on a hot asphault parking lot, all summer. This is still no guarantee that the bottom is totally dry but it's about as good as you are going to get.
As far as waiting between coats goes, let your nose be the guide no matter what it says on the paint can. If you are still getting strong xylene fumes from the previous coat, WAIT! Like one of the posters said, trapping the sovents between the layers is a no-no! Rushing things just to get all of it done in one day will leave you very mad and frustrated when it blisters on you again, shortly after relaunch.
Just in case anyone thinks that I'm full of it, I have been building and repairing boats since 1975, as well as building and repairing sails since 1983. I have seen many mistakes and made more than a few and I try to never make the same one twice. Rushing any job on anything because you want to get it done is a recipe for disaster.
Dave
Dave, what you are saying is cosistent with 2 other boats in my club. They are the only 2 that have used Interprotect 2000E and have the same experience.
From what you are saying I may as well remove/break the blisters. let dry out for the winter and sand all areas smooth in the spring then recoat with VC17M. Don't add any more barrier coat?
From what you are saying I may as well remove/break the blisters. let dry out for the winter and sand all areas smooth in the spring then recoat with VC17M. Don't add any more barrier coat?
Stef
Odyssey #146
Odyssey #146
Blisters
Stef, how bad is your blister problem? If you just have some here and there doing as you discribe is not a bad idea. If the whole bottom has blisters of varrying sizes, which is usually the case, it is totally a waste of time to try and open them all up. There are just too many AND new ones are forming under the laminate that you can't see/feel yet.
The only good reason to let a boat sit out for months to dry is if you are going to be doing total blister repair. If that is the case it's preferable to first strip the offending gelcoat/old barrior coat and whatever laminate it takes to get to good glass. Unstripped bottoms can and do dry over time sitting out, depending on how bad they are and the weather, but MUCH slower. I see that you are in PA. The winters up there aren't really much good for drying a boat bottom. It might even cause more damage. If you have water in the laminate and it freezes [expands], nothing good could come from it. There is no magic bullet or easy/cheap solution for real blister repair.
Dave
The only good reason to let a boat sit out for months to dry is if you are going to be doing total blister repair. If that is the case it's preferable to first strip the offending gelcoat/old barrior coat and whatever laminate it takes to get to good glass. Unstripped bottoms can and do dry over time sitting out, depending on how bad they are and the weather, but MUCH slower. I see that you are in PA. The winters up there aren't really much good for drying a boat bottom. It might even cause more damage. If you have water in the laminate and it freezes [expands], nothing good could come from it. There is no magic bullet or easy/cheap solution for real blister repair.
Dave
I think you're supposed to top off the VC-17m with VC thinner, so you end up with a full quart. I suspect that has something to do with having a little spare space at the top of the can when you mix in the powder so it doesn't run all over the outside of the can when stirring ... or maybe it's more subtle than that.
If memory serves me - the actual quantity of VC-17m in the can is .75 quart not 1 quart so when you calcualte your coverage you need five cans to get 4 quarts.
Harrison Pratt