timbo2 Posted October 9, 2012 Report Share Posted October 9, 2012 I'm now ready to apply 3 coats of epoxy to the interior and exterior of the little Mandy/Amanda boat I've built. Need some help with tipping off. I've rolled epoxy on the rudder pieces, then tipped off with those disposable foam brushes. The epoxy sets up quite rough, so much so that I must hit it with the sander again before applying the next coat. Is this typical? Am I not applying enough force with the disposable brushes? Perhaps a good brush to tip off with would be better. If so, how does one clean his brush when using epoxy? What I want to do is apply all 3 coats in one day which would probably preclude any sanding. Tim Quote Link to comment Share on other sites More sharing options...
Hirilonde Posted October 9, 2012 Report Share Posted October 9, 2012 I've rolled epoxy on the rudder pieces, then tipped off with those disposable foam brushes. The epoxy sets up quite rough, so much so that I must hit it with the sander again before applying the next coat. Is this typical? There are lots of people here with more experience in technique than me, and I am sure they will chime in. But if you have the time to do consecutive coats within the cure period, I would not sand no matter how rough. Each coat does not really make the last one more rough. And this way you sand only once. So even if it is rough, once is much better than 3 times. It does require a marathon session to get all 3 coats done within the 2 previous cure periods, yet after the set up time, but it is well worth it if you can. ......... how does one clean his brush when using epoxy? What I want to do is apply all 3 coats in one day which would probably preclude any sanding. Hardly worth the effort, and you likely won't get it clean enough any way. You can wrap it in a baggy and freeze it between coats. I do this for gluing stuff where small areas and multiple steps are involved, but not for coating large surfaces. Quote Link to comment Share on other sites More sharing options...
John Burritt Posted October 9, 2012 Report Share Posted October 9, 2012 Some questions - Are you epoxying over wood, or fiberglass? Are you using a slow-setting epoxy? If not, it may be setting up before you can get it smoothed. Are you applying a fairly liberal coat of epoxy? Not enough may be leaving the rough surface. Was the wood fairly hot when you coated it? If the coating appeared smooth when you wet it out and then turned bumpy, it may be outgassing (air bubbles). I'm sure others will have more questions & suggestions. Quote Link to comment Share on other sites More sharing options...
PeterP Posted October 9, 2012 Report Share Posted October 9, 2012 Acetone is a good solvent and so is vinegar at fraction of the cost. Wire brushing after good rinse gets most of the gunk out. Consider making your own tip-out "brushes" by cutting up foam rollers. Works out whole lot cheaper than disposable brushes. PeterP Quote Link to comment Share on other sites More sharing options...
Howard Posted October 9, 2012 Report Share Posted October 9, 2012 Michael Storer has some good basic, boat building info on his website. Coating plywood panels with epoxy is one of them: http://www.storerboatplans.com/Faq/precoatingsheets.html This info is for pre-coating panels, but I seem to recall he offers the same advice in his boat building plans. Of note is the suggestion to roll on a coat, then "slick" it with the same roller. Basically, hold the roller at an angle so it no longer rolls, but skids. This is a variation on the West System method of cutting a foam roller into strips and using a piece of dry roller to "tip" and smooth the epoxy. "Slicking" the rolled on coat is ostensibly faster, and eliminates the need for a tipping brush. How many coats you get on will depend on ambient temps and the hardener you use. Doing so will also depend on the epoxy you use. Rolling on a coat with the previous coat still tacky will not work well if your epoxy is subject to blushing. If you epoxy wants to blush, you are almost forced to wait until it dries so you can rinse the blush off and give it a quick scuff sand before going again. If you are working with a glued up boat, then anything you can do to minimize vertical surfaces will help, as anything but very light coats of epoxy will try to sag and run. As for the rough texture issue, is this on Okoume? I have found I get a rough, almost gritty or pebbly type response to my first coat of epoxy on bare Okoume plywood. The only way I found to minimize it was to lightly sand the panel first with a random orbital sander, pulling off the dust with a vacuum as I did. I have asked a lot of questions to a lot of people and nobody could ever explain to me why it happened, but it happened. Outgassing was a frequent suggestion, but this was not that. Sanding first was the only way I've been able to avoid it. Quote Link to comment Share on other sites More sharing options...
Alan Stewart Posted October 9, 2012 Report Share Posted October 9, 2012 The first coat on okume always dries rough in my experience. I suggest a first coat as a sealer and then sand it smooth with 80 grit. The second and third coats will go on very smooth and glossy. Even though the bare wood feels smooth The hairy fibers stand up and cause the roughness In the first coat. You can minimize the roughness by sanding the bare wood down to say 220 grit and then you might be able to do all 3 coats like you want. To minimize out gassing make Sure the temperature doesn't go up mid coating. Once the first coat has tacked up out gassing shouldn't really be a problem But blush could be as mentioned above. Quote Link to comment Share on other sites More sharing options...
hokeyhydro Posted October 9, 2012 Report Share Posted October 9, 2012 brush clean = vinegar followed by denatured alcohol. Works for me. For tip off I use a cheap bristle brush with about a half inch clipped off. That creates the stiffness/flexibility I like. Quote Link to comment Share on other sites More sharing options...
timbo2 Posted October 11, 2012 Author Report Share Posted October 11, 2012 Thanks for all the advice, guys. I'll see how the first coat goes on, and if rough let it cure, sand with 80 grit and follow with the other coats. Hopefully, as Alan says it should go one fine from there. I really like the link you gave Howard concerning pre-coating the panels. I'll try to remember to do that on the next boat! There's a lot of other good info there, too. Tim Quote Link to comment Share on other sites More sharing options...
timbo2 Posted October 18, 2012 Author Report Share Posted October 18, 2012 Well, the 3 coats of epoxy went on pretty well after all. I'll sand lightly before applying the primer. Painting question: I'm going to go with Interlux Brightside or Perfection. The Perfection is a 2 part epoxy and costs about double what the Brightside paint does. Since I'm probably going to go with 2 colors on the hull, and an off white on the interior, costs are becoming a consideration. Does anyone have any experience with these paints, and is the 2 part Perfection line worth it or needed over the one part Brightside line? After all the work I've put into this, I don't want to 'cheap out' on the paint now, but the two part with additives will be pushing $300 or so. I've zero experience painting a boat. Tim 1 Quote Link to comment Share on other sites More sharing options...
John Burritt Posted October 18, 2012 Report Share Posted October 18, 2012 Somewhat depends on how you're going to apply the paint. If you're going to spray it, I won't make any suggestions, as I have no experience doing it. For brushing - or more accurately rolling & tipping with a 2-part - I'd be looking at either AwlGrip or AlexSeal. AwlGrip's brushing reducer does wonders in maintaining a wet edge while you're painting. I've heard that the AwlGrip brushing reducer will also work w/ AlexSeal. For a 1-part, I'd talk to a reputable paint dealer about an industrial enamel. Color options may not be as great as "boat paints", they typically are very durable. Built & painted a boat for a guy who wanted it red. At the time, I couldn't find a viable red boat paint, so used "industrial red" (fire hydrant paint). It outlasted everything else the guy did to the boat. Quote Link to comment Share on other sites More sharing options...
Scott Dunsworth Posted October 18, 2012 Report Share Posted October 18, 2012 Graham highly recommended to me to use the two part when I painted my Belhaven. I chose to save two or three hundred dollars, used single part and ended up repainting after 3 years of heavy use. Never again will I use any single part, know matter what the manufacturer claims about their product. Many one parts will hold their shine a very long time, but who cares if it's all stained up and wont clean. Two part is good for a very long time. I sound pretty sure of myself, but been there and never again. Your going to get a lot of opinions on this and that was my Three cents worth! ;) ;) Quote Link to comment Share on other sites More sharing options...
Hirilonde Posted October 18, 2012 Report Share Posted October 18, 2012 I've heard that the AwlGrip brushing reducer will also work w/ AlexSeal Quite possibly as AlexaSeal was founded by former AwlGrip employees. But I would do a test before assuming it works. Quote Link to comment Share on other sites More sharing options...
Howard Posted October 18, 2012 Report Share Posted October 18, 2012 Marine paint is a difficult concept to get your arms around as so much information that is out there is either difficult to understand, or in conflict with itself. Case in point.......the link below takes you to the System 3 reference materials. Download the whole thing or just Section 8 (coincidence?) which talks about using paint: http://www.systemthree.com/reslibrary/m_published-literature.asp Brightsides mentions "alkyd" on the can, so oil based, and not something you should be using.....or so they say. But what does S3 know......they only make the stuff. Then there is CLC: http://www.clcboats.com/shoptips/finishing-tips/painting_polyurethanes.html So they actually suggest you use Brightsides? Key here seems to be the use of non-blushing epoxies. All this points to the notion that unless you have used a non-blushing epoxy, enamel (oil based) paints won't cure right. You might be able to isolate the epoxy from the paint with your primer, but to be on the safe side, the two part LPU paints are generally going to work best with most epoxy coated boats. You know it will look good and it will last. The other is an unknown. Quote Link to comment Share on other sites More sharing options...
Scott Dunsworth Posted October 18, 2012 Report Share Posted October 18, 2012 Howard I tried to PM you and your message box must be full. Quote Link to comment Share on other sites More sharing options...
Hirilonde Posted October 18, 2012 Report Share Posted October 18, 2012 Key here seems to be the use of non-blushing epoxies. All this points to the notion that unless you have used a non-blushing epoxy, enamel (oil based) paints won't cure right. You might be able to isolate the epoxy from the paint with your primer, but to be on the safe side, the two part LPU paints are generally going to work best with most epoxy coated boats. You know it will look good and it will last. The other is an unknown. My Spindrift is coated with 3 coats of West Sytem epoxy. It surely blushes, though I cleaned it well after doing 3 hot coats consecutively. I then primed the entire boat with 3 coats of Awlgrip 545 epoxy primer. The exterior is spayed with Alexaseal and the interior is rolled/tipped with oil based. I haven't had the slightest of issues. The interior did fade after leaving the boat in the water for 6 months straight, but no blistering, bubbling, pealing, etc.. I think a good epoxy primer is the key and of course prep work (de-blush, sand, clean). Nothing will stand up over the long haul like a 2 part LPU, but any paint will meet it's expectations if the prep and primer are good. Quote Link to comment Share on other sites More sharing options...
Scott Dunsworth Posted October 18, 2012 Report Share Posted October 18, 2012 I second what Dave said about the epoxy primer big time! I always used Epifanes, but I'm sure most are good. Quote Link to comment Share on other sites More sharing options...
Scott Dunsworth Posted October 18, 2012 Report Share Posted October 18, 2012 While we are talking about paints, my brother painted his topsides of his Coronado 25 with Epifanes two part and didn't order enough. He finished up with Interlux two part and said they were about the same with the exception the Epifanes flowed out better with the brush. Quote Link to comment Share on other sites More sharing options...
Charlie Jones Posted October 19, 2012 Report Share Posted October 19, 2012 A minor point here- there is simply no such thing as a totally "non-blushing" epoxy. Depending on climatological circumstances, they'll ALL blush to a certain extent. All epoxies contain amines- part of the curing process, and amine blush can occur with all of them. But it's also no big deal- ALL blush is water soluble- simply wash the hull down with fresh water and a rag, then dry it, before sanding or painting. On the paints- Brightsides I do not like, in colors. White is fine- colors are way too thin and take too many coats to cover well. It's basically an enamel anyway. But hey, on my own small trimaran, I used ACE Porch and deck enamel. about the same stuff as Brightsides really. Been through three Texas 200's so far and still looks good. And nothing to prevent using a good Alkyd. Alkyds have been used on boats for years, including epoxy coated boats. Won't last as long as a 2 part poly, but sure doesn't cost $50 a quart either Pic is of traveler-painted 2008. Quote Link to comment Share on other sites More sharing options...
Howard Posted October 19, 2012 Report Share Posted October 19, 2012 Howard I tried to PM you and your message box must be full. Interesting. I tried to do the same thing with Brent and got the same response. I can only suspect the Messing About PM feature must be on the fritz? Scott: Want a private email or cell number? Quote Link to comment Share on other sites More sharing options...
Mike Vacanti Posted October 19, 2012 Report Share Posted October 19, 2012 Somewhat depends on how you're going to apply the paint. If you're going to spray it, I won't make any suggestions, as I have no experience doing it. <snip> If you want to spray LPU paint (perfection is a LPU) you must use a forced air respirator. When atomized, LPU paint is very toxic. When brushing it you can get away with using an organic filter mask. Quote Link to comment Share on other sites More sharing options...
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