Return-Path: Received: from [65.33.160.13] (account marv@lancaironline.net) by logan.com (CommuniGate Pro WebUser 4.2) with HTTP id 383917 for lml@lancaironline.net; Sun, 29 Aug 2004 19:46:19 -0400 From: "Marvin Kaye" Subject: Re: [LML] Re: Micro use for Wings To: "Lancair Mailing List" X-Mailer: CommuniGate Pro WebUser Interface v.4.2 Date: Sun, 29 Aug 2004 19:46:19 -0400 Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format="flowed" Content-Transfer-Encoding: 8bit Jeff Paden wrote: " I Would like to know if we are useing micro to fill the low spots in the wings or there is something easier or better. " Many good points brought up by several builders. As is mentioned in most posts, "your mileage may vary" with different techniques, as that's always the way... what works well for one person may be a nightmare for another. This is why it's great to get as much input as possible and then experiment to find the methodology that 1) you are most comfortable with and 2) gives you the best results in the shortest time with the least effort. I've had the great fortune to work with quite a few builders over the years, and have picked up more than a trick or two from paying attention or carrying an experiment to a different level. When it comes to filling large areas (such as wing skins, fuselage panels, etc) I prefer using micro that is a bit wetter than usual, and doing the troweling to a smooth surface through peel ply. You can buy peel ply by the yard from ACS and use a wide drywall knife (Home Depot, Lowe's, etc) to move large amounts of material with each "scrape". For curvier areas, wide body putty squeegees also work well... it just takes some practice to develop the feel for getting the proper curve to the blade. Working through peel-ply really helps simplify the process, and you'd be amazed at the results you get this way. I freely confess that I learned this trick from someone here on the LML several years ago... thank you to whoever you are, sorry I don't remember your name. I second the motion regarding all the stuff about long sanding blocks, high-grade 3M sandpapers, etc. Getting good with an inline air sander (2" x 17.5") helps immensely as well, especially when you get to the final stages where the big blocks have already been used to knock down the bumps and you're trying to get that final smoothing. Another interesting trick I sort of stumbled upon was using different colors of primer. Both WLS and K36 are light grey in color. If you lightly spray on your first coat of (light grey) primer you can use it as a guide coat without the mess brought on by Krylon or some other cheap paint. You sand off just about all of that first coat (getting down to the raw glass or CF surface), fix the big depressions with micro, resand, then reprime with a darker primer... PPG Omni comes to mind. (Omni is also much less expensive than WLS or K36.) You sand off most of that next coat of primer as well, recheck your surfaces for smoothness and use glazing putty to fill the last of the pinholes, scratches, or minor depressions, final sand to flatten, then apply your final primer coat, again in the light color. I realize that priming 3 times might seem like a lot, but in reality none of those layers of primer need to be very thick. When you wet sand that last layer you'll know when you're sanding too much in one place if the darker primer starts to peek through. If you apply the first coat of primer a little early it works out just fine, as it's lots easier to see what you need to see for that primary leveling when you're dealing with a primed (uniformly colored & textured) surface between the high spots. As I mentioned earlier... your mileage may vary. These methods have worked well for me and I just thought I'd share them seeing as how you asked. Have fun, take your time, and use the palm of your hand to check your surfaces for smoothness. You'll feel imperfections that are totally invisible to the eye.