Hi all -- I plan to start applying the first 2 of 4 coats of Interprotect tomorrow morning. My boat is supported by 5 jackstands. What is the most efficient procedure to follow so that the yard crew has to move the stands the fewest number of times? Thanks, again , for the advice. (this is not a trick question, I have reached a mental roadblock) Steve
bottom coating process
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I challenge all!
can we answer this fellows question without the usual jackstand/boatstand/poppit BS? I know we can do it if I can type this fast enough!
can we answer this fellows question without the usual jackstand/boatstand/poppit BS? I know we can do it if I can type this fast enough!
What Boat SIze?
Add a couple more stands so you can move one when you need to. With just five, I wouldn't move any but the one under the bow; with three on each side and one under the bow, you'd have some flexibility.
Add a couple more stands so you can move one when you need to. With just five, I wouldn't move any but the one under the bow; with three on each side and one under the bow, you'd have some flexibility.
It's hard to do it in less than one
If your objective is to minimize the moves, do what you can with the pads where they are and simply add the 4 coats to the bare spots once the rest of the hull is done. It doesn't need to be one continuous coat and what overlap results is trivial.
If your objective is to minimize the moves, do what you can with the pads where they are and simply add the 4 coats to the bare spots once the rest of the hull is done. It doesn't need to be one continuous coat and what overlap results is trivial.
Safest is to move the jackstands when the job is cured.
.... the go back fill the 'holes' after the previous coating fully cures. If you move the jackstands around and place them on a section that isnt FULLY cured you will deform the previous coats. If you want the least amount of problems with adhesion of bottom paint, continue with your max amount of coats, then immediately put on at least two coats of bottom paint ... all without letting any coat fully cure. This will minimize the amount of 'amine blush' that has to be removed before you apply bottom paint .... and you will minimize any bottom paint 'adhesion problems' later on. If you let the barrier coat fully cure before you put on bottom paint, you will have to scrub the interprotect with HOT water, then sand the surface. 'Hot-coating' the bottom paint will save a laborious sanding step. If you are interested in a smooth bottom coat of barrier coat that requires minimal sanding & results in minimal 'roughness' (from the roller), let me know and I will post it. Downside is that you have to do this almost continually for about 18-20 hours and with only 'catnaps' in-between coats.
.... the go back fill the 'holes' after the previous coating fully cures. If you move the jackstands around and place them on a section that isnt FULLY cured you will deform the previous coats. If you want the least amount of problems with adhesion of bottom paint, continue with your max amount of coats, then immediately put on at least two coats of bottom paint ... all without letting any coat fully cure. This will minimize the amount of 'amine blush' that has to be removed before you apply bottom paint .... and you will minimize any bottom paint 'adhesion problems' later on. If you let the barrier coat fully cure before you put on bottom paint, you will have to scrub the interprotect with HOT water, then sand the surface. 'Hot-coating' the bottom paint will save a laborious sanding step. If you are interested in a smooth bottom coat of barrier coat that requires minimal sanding & results in minimal 'roughness' (from the roller), let me know and I will post it. Downside is that you have to do this almost continually for about 18-20 hours and with only 'catnaps' in-between coats.
No amine blush?
Rich, Not to nitpik, but I can't find any mention of amine blush on the Interprotect data sheet. It's best to overcoat while tacky, because you then get a chemical as well as mechanical bond, but it can be overcoated completely cured, as long as it's sanded. No need for a hot water or solvent wash. Larry
Rich, Not to nitpik, but I can't find any mention of amine blush on the Interprotect data sheet. It's best to overcoat while tacky, because you then get a chemical as well as mechanical bond, but it can be overcoated completely cured, as long as it's sanded. No need for a hot water or solvent wash. Larry
Agree!!
I agree 100% with Rich that "Hot Coating" works!! I had a chance to see one of my old boats out of the water this past fall. I had hot coated it with Micron CSC 8 years ago and to this day there is no paint peeling from the barrier coat layer. Don't let the final barrier coat layer fully kick before applying the bottom paint.. It's called "hot coating" and it works...
I agree 100% with Rich that "Hot Coating" works!! I had a chance to see one of my old boats out of the water this past fall. I had hot coated it with Micron CSC 8 years ago and to this day there is no paint peeling from the barrier coat layer. Don't let the final barrier coat layer fully kick before applying the bottom paint.. It's called "hot coating" and it works...
Use Different Color First Coat of Bottom Paint
Speaking of bottom paint, when you get ready to apply bottom paint It helps to use a different color of for the first coat of bottom paint so later, when you';re sanding, you know that you've gone far enough.
Speaking of bottom paint, when you get ready to apply bottom paint It helps to use a different color of for the first coat of bottom paint so later, when you';re sanding, you know that you've gone far enough.
Larry ---
My experience in the past is that if you dont scrub with hot water then sand you will have adhesion problems with bottom paint when using Interprotect. Yup, there is no mention of amine blush on the Interprotect tech data sheets but I'd still be quite wary .... some epoxies produce a lot of blush others dont; so, its always better to 'hot coat' each successive layer. What I was alluding to in my previous post is that I use a roller to apply the first two coats of barrier, then work up each successive coat using a roller but quickly followed up with a large polyethylene trowel .... this will knock the peaks down and fill the valleys and will result in a very flat surface. Using just a roller will result in a knobby or 'pimply' surface. The 'key' here is to get the proper mil thickness of barrier on, then simply 'fill' all the valleys with additional barrier .... so that you wind up with a fair and smooth hull. The process is the very same as applying polyester or epoxy when laying up a hull etc. on a MALE plug mold. Unfortunately you sometimes have to let the intermediate coats fully cure and sand down some of the 'mistakes'. When sanding I sand down only the high peaks or 'mistakes'. I do the same when applying bottom paint .... so I can produce a bottom finish thats as smooth as a babys ass ..... and doesnt require much sanding or the use of long 'fairing/feathering' boards'. A fair and FLAT hull does wonders for boat speed especially in 'light wind' sailing. Interestingly when I apply ablative bottom paint this way it seems to LAST much much longer than when applied with 'just a roller' .... probably due to the reduction of overall 'surface area' of the paint due to the FLAT surface.
My experience in the past is that if you dont scrub with hot water then sand you will have adhesion problems with bottom paint when using Interprotect. Yup, there is no mention of amine blush on the Interprotect tech data sheets but I'd still be quite wary .... some epoxies produce a lot of blush others dont; so, its always better to 'hot coat' each successive layer. What I was alluding to in my previous post is that I use a roller to apply the first two coats of barrier, then work up each successive coat using a roller but quickly followed up with a large polyethylene trowel .... this will knock the peaks down and fill the valleys and will result in a very flat surface. Using just a roller will result in a knobby or 'pimply' surface. The 'key' here is to get the proper mil thickness of barrier on, then simply 'fill' all the valleys with additional barrier .... so that you wind up with a fair and smooth hull. The process is the very same as applying polyester or epoxy when laying up a hull etc. on a MALE plug mold. Unfortunately you sometimes have to let the intermediate coats fully cure and sand down some of the 'mistakes'. When sanding I sand down only the high peaks or 'mistakes'. I do the same when applying bottom paint .... so I can produce a bottom finish thats as smooth as a babys ass ..... and doesnt require much sanding or the use of long 'fairing/feathering' boards'. A fair and FLAT hull does wonders for boat speed especially in 'light wind' sailing. Interestingly when I apply ablative bottom paint this way it seems to LAST much much longer than when applied with 'just a roller' .... probably due to the reduction of overall 'surface area' of the paint due to the FLAT surface.
roller problem
Another issue. I applied my first coat of Interprotect today and almost everything went fine. My one problem was the very short working time of the roller covers before they started to undo. I was using West yellow foam covers, that I assumed were solvent resistent, and were sold to me on that basis. Their packaging says that they are for epoxy application. So, any suggestions for longer lasting roller covers. I have some 1/4" covers with phenolic cores (label says solvent resistent) that I was planning to use for bottom paint, but would those be better than the the West yellw foam for the Interprotect? Thanks again Steve
Another issue. I applied my first coat of Interprotect today and almost everything went fine. My one problem was the very short working time of the roller covers before they started to undo. I was using West yellow foam covers, that I assumed were solvent resistent, and were sold to me on that basis. Their packaging says that they are for epoxy application. So, any suggestions for longer lasting roller covers. I have some 1/4" covers with phenolic cores (label says solvent resistent) that I was planning to use for bottom paint, but would those be better than the the West yellw foam for the Interprotect? Thanks again Steve
Brush or trowel
Rich, I have followed your post and I do not quite understand the concept of a large trowel for the bottom paint. I could see it scraping it all off. Never having done a barrier coat I can't comment. Sooo - if you were applying an ablative bottom paint would you roll it on and brush it out lightly to get that smooth finish or would you still go with the plastic trowel? Thanks Don
Rich, I have followed your post and I do not quite understand the concept of a large trowel for the bottom paint. I could see it scraping it all off. Never having done a barrier coat I can't comment. Sooo - if you were applying an ablative bottom paint would you roll it on and brush it out lightly to get that smooth finish or would you still go with the plastic trowel? Thanks Don
Steve ----
Yup, the yellow WEST rollers only last about 15-20 minutes ... then fall apart. The 'other' rollers last even less. You need a good supply 4-5 per side of a 30-35 ft. boat. What happens is the 'sponge' swells, and breaks loose its bond to the phenolic roller. The 'faster' you can roll the more mileage you can get out of a roller ..... until the sponge 'swells'.
Yup, the yellow WEST rollers only last about 15-20 minutes ... then fall apart. The 'other' rollers last even less. You need a good supply 4-5 per side of a 30-35 ft. boat. What happens is the 'sponge' swells, and breaks loose its bond to the phenolic roller. The 'faster' you can roll the more mileage you can get out of a roller ..... until the sponge 'swells'.
I think Rich
Don, I think Rich is referring to what I always called a float trowel. Has no notches, and the plastic is a little flexible, and would follow the hull contours much better than a metal one. You can buy a plain old plastic trowel, and use the back side, which normally has no notches. I have never done this, but it sure makes sense.
Don, I think Rich is referring to what I always called a float trowel. Has no notches, and the plastic is a little flexible, and would follow the hull contours much better than a metal one. You can buy a plain old plastic trowel, and use the back side, which normally has no notches. I have never done this, but it sure makes sense.
Don ---
What I do for barrier coat or for bottom paint: If a new coat over 'bare' I apply the first coat with a roller only and let it set to almost full cure. I take a sharp scraper and remove some partly cured material and measure the thickness with a micrometer (all the barrier coatings are scheduled by mil (thousandths of an inch) thickness. If the 'peaks' (left by the roller) arent up to the schedule mil thickness I roll on another coat. When the 'peak' mil thickness is slightly 'over' the schedule mil thickness I wait until full cured, then I lightly sand the top of the peaks only to create a flat top to the peaks only. The flat tops are again measured and if correct for subsequent 'layers' I quickly roll on a wide stripe (diagonally) and quickly draw a polyethylene trowel across the flat peak .... to begin the 'fill' of the valleys. I make the stripes approx 3 ft wide, leave approx 1 ft. 'dry' between the stripes: 3 ft. filled stripe, 1ft. dry stripe, 3 ft filled striped ... all the way around the boat. When the original stripe begins to fully (but not totally) cure, I go back and fill in the 1 ft. wide stripes with a roller quickly followed by the PE trowel. The trowel 'rides' on the top of the 'flattened' peaks. Again, the polyethylene trowel rides along the flat topped peaks and pushes paint or barrier down into the valleys. (Yes, you have to clean the trowel with solvent many times). Then when the barrier begins to cure and can stand another application I change direction of the stripes about 90 degress and start all over again with 3ft. wide stripes, leaving a 1 ft. 'dry area' in between, etc. If the 'fill' isnt full into the 'vallleys', then I proceed with another set of stripes until the lay-up becomes 'fair' and smooth. I continue with the stripes (all at different angles) until the hull is SMOOTH and fair ..... then apply bottom paint, first with a roller until almost cured, etc. then sand just the peaks flat and begin with the wet stripes/dry stripes until the job is done. This is the way one 'fairs' a male plug mold when fiberglassing. With bottom paint that was applied a season or two prior ... I scrape loose a sample to see how thick the old bottom paint is.... then either direct roll and quickly trowel just to fill what has 'ablated away' OR apply a single 'knobbly' roll only coat .. let partly cure, then knock the paint off the flats of the 'peaks' until the whole job is smooth and fair. All the above produces a very smooth and faired hull. Rollers alone leave a 'pimply' effect which can rob a lot of speed from a boat. The smoother the bottom the less heel, the faster the boat ... especially in very light wind conditions.
What I do for barrier coat or for bottom paint: If a new coat over 'bare' I apply the first coat with a roller only and let it set to almost full cure. I take a sharp scraper and remove some partly cured material and measure the thickness with a micrometer (all the barrier coatings are scheduled by mil (thousandths of an inch) thickness. If the 'peaks' (left by the roller) arent up to the schedule mil thickness I roll on another coat. When the 'peak' mil thickness is slightly 'over' the schedule mil thickness I wait until full cured, then I lightly sand the top of the peaks only to create a flat top to the peaks only. The flat tops are again measured and if correct for subsequent 'layers' I quickly roll on a wide stripe (diagonally) and quickly draw a polyethylene trowel across the flat peak .... to begin the 'fill' of the valleys. I make the stripes approx 3 ft wide, leave approx 1 ft. 'dry' between the stripes: 3 ft. filled stripe, 1ft. dry stripe, 3 ft filled striped ... all the way around the boat. When the original stripe begins to fully (but not totally) cure, I go back and fill in the 1 ft. wide stripes with a roller quickly followed by the PE trowel. The trowel 'rides' on the top of the 'flattened' peaks. Again, the polyethylene trowel rides along the flat topped peaks and pushes paint or barrier down into the valleys. (Yes, you have to clean the trowel with solvent many times). Then when the barrier begins to cure and can stand another application I change direction of the stripes about 90 degress and start all over again with 3ft. wide stripes, leaving a 1 ft. 'dry area' in between, etc. If the 'fill' isnt full into the 'vallleys', then I proceed with another set of stripes until the lay-up becomes 'fair' and smooth. I continue with the stripes (all at different angles) until the hull is SMOOTH and fair ..... then apply bottom paint, first with a roller until almost cured, etc. then sand just the peaks flat and begin with the wet stripes/dry stripes until the job is done. This is the way one 'fairs' a male plug mold when fiberglassing. With bottom paint that was applied a season or two prior ... I scrape loose a sample to see how thick the old bottom paint is.... then either direct roll and quickly trowel just to fill what has 'ablated away' OR apply a single 'knobbly' roll only coat .. let partly cure, then knock the paint off the flats of the 'peaks' until the whole job is smooth and fair. All the above produces a very smooth and faired hull. Rollers alone leave a 'pimply' effect which can rob a lot of speed from a boat. The smoother the bottom the less heel, the faster the boat ... especially in very light wind conditions.
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