Well it's boat maintinance time again up here in Ontario. I had a bit of a paint disaster recently which has left all kinds of waterspot-like marks on my Epifanes Bootlak. Short of grinding it all down and repainting. What can I do to fix this? I have a good porter cable, some super fine grit sandpaper from 800-1500 then some micromesh that goes up to 12000 grit. After that I suppose I could go for wax. How can I bring that perfect shine back to my canoe?
How to repair spotty paint?
- Thread starter victorw
- Start date
Ric Altfather
WCHA #4035
Victor,
Just scuff it and give it another coat. Use the 1200 - 1500 or a 3M green pad for the scuff. No need to get down to the base.
Regards,
Ric Altfather
Just scuff it and give it another coat. Use the 1200 - 1500 or a 3M green pad for the scuff. No need to get down to the base.
Regards,
Ric Altfather
Thank you.
Although I could repaint it, I'm trying to avoid that as I don't have access right now to a dust-free environment. I just wanted to plumb the people here and find out if there has been any precident set for polishing the paint, or if anyone has tried it.
Although I could repaint it, I'm trying to avoid that as I don't have access right now to a dust-free environment. I just wanted to plumb the people here and find out if there has been any precident set for polishing the paint, or if anyone has tried it.
Todd Bradshaw
Sailmaker
Most paint can be polished if you have the energy, but there are several factors that can effect the success of the final outcome.
- The hardness of the particular paint you're using, which varies.
- How dry it is - new paint should be allowed to dry (and/or shrink down) for at least a week before you attack it with sandpaper.
- How thick it is - It's really annoying to get it 75% along in the polishing process and to start seeing the layers under it beginning to show through.
- How smooth or fair the object's surface really is - You can't do a good polish job on a surface covered with tiny hills and valleys and once beyond about 320 grit, you pretty much lose the ability to level defects.
If you go through all the Micromesh grits, wet-sanding by hand, you will get some very serious gloss and all you'll need for the final polish is a cloth and a bit of polishing compound (3M Finnesse-It or similar). How long and how hard you need to work each grit depends on the hardness of the surface. Most non-catalyzed paints and varnishes are fairly soft and don't take very long. You simply want to eliminate all the scratches that the previous grit left. Your cutting process was taken care of during the 220-320 phase, so now you're just working on the very surface.
Micromesh is great stuff, but expensive. Wet sanding not only lubricates the surface, but it also helps keep the Micromesh from loading up with paint, so it lasts a lot longer. I use the 5" disks made for random orbit sanders, but never on a machine. With that kind of speed on paint or resin, they would load up in a couple of minutes from the heat and soon be worthless.
Whether or not it's worth trying on a boat would depend on how big the areas are. A few spots here and there to match surrounding paint is one thing - however, if it turns out to be the entire bottom of a canoe or more, that might be more work than most rational folks can justify (in case any of us are truly rational when it comes to canoe stuff, which is debatable merely by our presence on this forum).
- The hardness of the particular paint you're using, which varies.
- How dry it is - new paint should be allowed to dry (and/or shrink down) for at least a week before you attack it with sandpaper.
- How thick it is - It's really annoying to get it 75% along in the polishing process and to start seeing the layers under it beginning to show through.
- How smooth or fair the object's surface really is - You can't do a good polish job on a surface covered with tiny hills and valleys and once beyond about 320 grit, you pretty much lose the ability to level defects.
If you go through all the Micromesh grits, wet-sanding by hand, you will get some very serious gloss and all you'll need for the final polish is a cloth and a bit of polishing compound (3M Finnesse-It or similar). How long and how hard you need to work each grit depends on the hardness of the surface. Most non-catalyzed paints and varnishes are fairly soft and don't take very long. You simply want to eliminate all the scratches that the previous grit left. Your cutting process was taken care of during the 220-320 phase, so now you're just working on the very surface.
Micromesh is great stuff, but expensive. Wet sanding not only lubricates the surface, but it also helps keep the Micromesh from loading up with paint, so it lasts a lot longer. I use the 5" disks made for random orbit sanders, but never on a machine. With that kind of speed on paint or resin, they would load up in a couple of minutes from the heat and soon be worthless.
Whether or not it's worth trying on a boat would depend on how big the areas are. A few spots here and there to match surrounding paint is one thing - however, if it turns out to be the entire bottom of a canoe or more, that might be more work than most rational folks can justify (in case any of us are truly rational when it comes to canoe stuff, which is debatable merely by our presence on this forum).
Dave Wermuth
Who hid my paddle?
Polishing compound?
You may try some polishing compound. sounds like you have minor spots? I once shined up the gelcoat of a faded runabout with the stuff.
You may try some polishing compound. sounds like you have minor spots? I once shined up the gelcoat of a faded runabout with the stuff.
Try some polishing compound from an autobody paint store. They often have a number of grits so get something near the finest.
I use the Optimum Series http://www.autogeek.net/optimum-compound.html and/or http://www.autogeek.net/opt400.html (depending on the amount I need to remove) to give a deep shine to the French Polish on my guitars. I also buffed up my Epifanes varnished stripper with Optimum Compound and it came out great. I don't think the paint you're using would be any softer than the shellac on the guitars or the canoe varnish so it should be fine. Try it on a little sample first just to be sure it doesn't react with the paint. However, I doubt there will be a problem.
3M polishing compounds have fillers which tend to mask the problem rather than remove it (Optimum has zero fillers). I've tried 3M and it looks great at first but give it a couple weeks and the shine starts to go. It's not my first choice.
I use the Optimum Series http://www.autogeek.net/optimum-compound.html and/or http://www.autogeek.net/opt400.html (depending on the amount I need to remove) to give a deep shine to the French Polish on my guitars. I also buffed up my Epifanes varnished stripper with Optimum Compound and it came out great. I don't think the paint you're using would be any softer than the shellac on the guitars or the canoe varnish so it should be fine. Try it on a little sample first just to be sure it doesn't react with the paint. However, I doubt there will be a problem.
3M polishing compounds have fillers which tend to mask the problem rather than remove it (Optimum has zero fillers). I've tried 3M and it looks great at first but give it a couple weeks and the shine starts to go. It's not my first choice.
Todd Bradshaw
Sailmaker
Polishing compound is certainly worth trying and if it does the job, it's likely to be the fastest, easiest way to do it. However, it tends to be a rather ineffective cutting compound if you have to go much deeper than the surface. In that case, you may find that ultra-fine sanding is a better bet and once you're through the bad spots, you can bring it back up to a nice gloss.
I don't know what sort of "fillers" 3M theoretically puts in their polishing compounds, but I haven't had any problems with the shine fading after a couple of weeks (or a couple of years for that matter). I use water-based varnish as a top coat on instruments, rather than French polish, but after the Micromesh treatment, wet-sanding up through 12,000 grit and 3M polishing compound by hand on a rag, I seem to get very good gloss and it stays that way. I do seal the pores with a coat of wax after polishing, but once a surface is sanded that fine, the polishing compound doesn't have to do much or hide anything. The 12,000 grit sanding by itself usually yields a better shine than some factory finishes and the polish just finishes off the job. On a canoe, as I mentioned before, it's all a matter of how much area you have to fix, how much time you have to devote to the task and how critical it is to you to have a flawless finish on a boat.
I don't know what sort of "fillers" 3M theoretically puts in their polishing compounds, but I haven't had any problems with the shine fading after a couple of weeks (or a couple of years for that matter). I use water-based varnish as a top coat on instruments, rather than French polish, but after the Micromesh treatment, wet-sanding up through 12,000 grit and 3M polishing compound by hand on a rag, I seem to get very good gloss and it stays that way. I do seal the pores with a coat of wax after polishing, but once a surface is sanded that fine, the polishing compound doesn't have to do much or hide anything. The 12,000 grit sanding by itself usually yields a better shine than some factory finishes and the polish just finishes off the job. On a canoe, as I mentioned before, it's all a matter of how much area you have to fix, how much time you have to devote to the task and how critical it is to you to have a flawless finish on a boat.
Attachments
Sorry Gil. When dealing with Luthiers and their "finishes" these things regularly take on a life of their own. The obsessive nature of the beast (aka the luthier) kicks in.
BTW, very pretty guitars Todd. I don't make that style but I certainly appreciate their beauty.
BTW, very pretty guitars Todd. I don't make that style but I certainly appreciate their beauty.
Todd Bradshaw
Sailmaker
For me, the music and boats have always gone hand in hand. In the beginning, the rock and roll business supported my boating habit and now the boat and sail work supports my guitar habit. The first big music check I ever got was an advance from Elektra records in 1972. The first two things I bought with it were the keel-less 16' Old Town Guide that still hangs in my garage today and an Old Town Berrigan decked whitewater canoe.
For finishes on wooden boats and canoes though, I can't see trying to create a piano or guitar-like finish. I actually want my paint to look like paint - but paint which has been applied with care. This can include a few subtle brush marks, maybe even a bit of canvas texture and something other than a high-gloss surface. I don't see much reason to try to make a wooden canoe look like a fiberglass boat that was popped out of a polished mold. I'd rather it look like a real canoe that actually gets used once in a while. I have nothing against a good fiberglass boat or canoe, but there are a good number of fiberglass canoes where the only really good thing about their construction is the shine on the outside. I'll take a well made hull with a decent paint job that looks like a living, breathing human actually did it for my paddling adventures.
For finishes on wooden boats and canoes though, I can't see trying to create a piano or guitar-like finish. I actually want my paint to look like paint - but paint which has been applied with care. This can include a few subtle brush marks, maybe even a bit of canvas texture and something other than a high-gloss surface. I don't see much reason to try to make a wooden canoe look like a fiberglass boat that was popped out of a polished mold. I'd rather it look like a real canoe that actually gets used once in a while. I have nothing against a good fiberglass boat or canoe, but there are a good number of fiberglass canoes where the only really good thing about their construction is the shine on the outside. I'll take a well made hull with a decent paint job that looks like a living, breathing human actually did it for my paddling adventures.