---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Sat 12/29/12: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:07 AM - Re: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? (goff) 2. 11:34 AM - Re: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? (Bud Yerly) 3. 03:18 PM - Re: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? (craig) ________________________________ Message 1 _____________________________________ Time: 10:07:23 AM PST US Subject: Europa-List: Re: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? From: "goff" Yes, allow six months. Even then it won't be perfect. Goff G-CHOX Read this topic online here: http://forums.matronics.com/viewtopic.php?p=391162#391162 ________________________________ Message 2 _____________________________________ Time: 11:34:32 AM PST US From: "Bud Yerly" Subject: Re: Europa-List: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? Great advice Graham. We learned the hard way here at the shop. Consistency is the key. I mix the expand cell until the stick practically or does break when mixing then allow it to sit for 20 minutes to gas off and apply with a plastic spatula. If you leave it thin enough to roll it on, it will be heavy. So make it thick enough not to sag but not dry enough that you can't spread it without it rolling off. I'm not at the shop but I believe we use a 4 to one ratio for thin and 6 to one for thick. Cleanliness of the surface is next to Godliness and a careful scuffing with 80 grit is all that is required for bond. If your cured filler is gooey and doesn't seem to sand without clogging, check your epoxy mix ratio and your expand cell amount added and the all important cure temp. I use Aeropoxy because it cures at 75 degrees or higher in low humidity in 8 hours and cures pretty rock solid. Ampreg 21 likes to be warm and dry, closer to 100 to 130 F and cures slow. Alas, even the Superfil has a slightly gooey top coat when cured.. Using the cheese grater type wood rasp or plane is good for us amateurs to knock off that skim layer, then give it a day and go to sandpaper. Where we usually screw up is we put too little filler on. The pros put on more filler and leave 90% of it on the floor. My body shop uses Superfil because of its consistency and cures it in the paint booth in dry and warm conditions. A thicker layer cures quite well. If it is applied in a thin film, by the time you get the goo layer off, you have no filler left. Allow the Superfil or Expandcell to set after mixing for 20 minutes (at 75 F) then spread to a 1/8 inch coat. The pros can do a smooth application but they and I leave the ridges and drag lines alone. Like a scab, don't pick at it. Superfil cures fully overnight at about 80 degrees, but runs on vertical surfaces like the fuselage side so be prepared. After cure, they cut it with the mud hog (large random orbital sander with 55 or 60 grit) and they throw sand paper away as soon as it clogs. For finishing, they use a random orbital sander with a 2 foot by 9 inch plate as the sanding platform, giving superb results. Johnny can fill an XS in a week, but cure time has to be perfect as well as the workload in his shop. I find for quick jobs, I use expand cell mixed thick and sprinkle a bit of plastic micro or Cabosil on top to make it sandable quicker. The micro/cabosil sprinkle just reduces the gummy top coat as it absorbs some of the goo. A friend of mine with a scratch built Long EZ filled his weave with wet epoxy and sprinkled on 3M glass sphere micro (rather than Expandcel which are an expanded plastic sphere very compatible with epoxy resins) in large quantities and allowed it to cure. It is a bit heavy. He vacuumed off the dust (he has a bagged Shop Vac) and then lightly sanded the surface to get it smooth but with irritating glass bubbles everywhere. Now that the weave was filled, he then applied Superfil over the now smoother but roughened surface. If your Classic wing is very rough, like mine was, you can use thick fishing line or string trimmer line, hung every couple feet to judge the thickness of your filler as others have written about. Then backfill the line holes. Sand until you start seeing the color of the glass coming through on the high spots. Sand with 80 grit then finish to 150 or 220. Coat with primer such as Dupont 2K or with the finishing system of your choice. Sand again down to 320 grit and prime again. Be sure to use a good UV protection polyurethane paint for your final finish. It will be gorgeous. Superfil is my preferred filler. I believe you get what you pay for. However, I still use Expandcel quite a lot. Support your piece well as some components tend to sag a bit and I have built in a bent flap by sanding without center support and made the upper surface flat but the flap bent under my sanding pressure... Oh well, sand it off and redo it is the cure. Please use caution and a good mask when using fillers. 3 M Micro glass spheres will kill your eyes and lungs, Cabosil isn't a lot safer as it is silica, and Expandcel uses an expanded plastic sphere or cell and Superfil supposedly uses the same (it is not talc per se) but that isn't completely safe either though it has a pretty clean MSDS sheet. So wear protection. Get good shoes and a block sander and "git-er-done". Regards, Bud Yerly Tech support. ----- Original Message ----- From: GRAHAM SINGLETON To: europa-list@matronics.com Sent: Friday, December 28, 2012 8:06 PM Subject: Re: Europa-List: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? Dave I use a 1/6 by volume addition of Cabosil (colloidal silica) mixed with the expancell. It enables about 50% more expancell to be added to the same amount of resin. It is best to be consistent as possible with the amount of resin and expancell you mix to avoid variations in the filler Superfil is an easier solution but expensive. For rough sanding I use a very sharp small wood plane, (Russ Lefevre gave me that tip) it cuts through the incompletely cured resin: the heat of sanding softens the resin unless it is fully cured, (which takes days,) and that clogs the paper. Graham ------------------------------------------------------------------------- ----- From: G-ODTW To: europa-list@matronics.com Sent: Friday, 28 December 2012, 20:40 Subject: Europa-List: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? > I thought it a good idea to get my tailplanes balanced before I put my top on. They needed filling (I used Ampreg21/Expancel as per Europa manual) & then will need painting. But I am now finding it a heck of a job to sand the filler. After 2 days of it, I have had enough. The sandpaper constantly clogs, and it is bl**** hard work - And my Classic wings are much bigger than the tail! Some people seem instead to use Superfil. But I am also told that SP106 is the resin many people use for the surface filling job, which sands without problems, presumably with the supplied Expancel. Many folk have trodden this path before me, using many methods. 20 years on, is there now a "best practice" for filling / sanding / painting? All advice greatfully received. Thanks. Dave Walters. -------- David Walters Read this topic online here: http://forums.matronics.com/viewtopic.php?p=391094#391094 this year's Terrific Free Incentive Gifts &nbsd onics.com/Navigator?Europa-List" target="_blank">http://www.matronics.com=========== ============ ________________________________ Message 3 _____________________________________ Time: 03:18:09 PM PST US From: "craig" Subject: RE: Europa-List: Filling/Painting Classic wings & Tail. SUPERFIL? SP106? As always great advice from bud, one thing I found when doing my tailplanes was that it seems much easier to Sand if the filler is left for a few days or more to cure. Sanding a few hours after cure using RADID hardener seemed very hard work, paper continually clogging But the same surface a couple of days later was much better, and no clogging Good luck craig ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message europa-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Europa-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/europa-list Browse Digests http://www.matronics.com/digest/europa-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.