Mailing List lml@lancaironline.net Message #37903
From: <Sky2high@aol.com>
Sender: <marv@lancaironline.net>
Subject: Re: [LML] Primers
Date: Fri, 29 Sep 2006 09:53:02 -0400
To: <lml@lancaironline.net>
In a message dated 9/28/2006 2:43:50 P.M. Central Standard Time, toucan@Satx.rr.com writes:
    Yes, some paint manufacturers are pushing the water-based products, mainly because the EPA is coming down ever harder on VOC's (volatile solvents) in the older formulations.  Having had one bad experience with water-based primers, however, I'd say stay away from them until they've been in use long enough to have a large, happy customer base.  In other words, let someone else be the guinea pig on something cheaper than your Lancair.
    As for seeing fabric weave, in just the right light I've been able to do that with all three planes I've finished, one painted with Siemens products, one with PPG, and the third with Imron.  Check some of the planes at your next local fly-in.  It seems that polymerization (cure) of these paints is not quite an on/off, 0 or 1 affair.  Over time, the process goes slower and slower, but probably doesn't reach near zero until after you've done your wet-sanding and buff-out.  If you're really a perfectionist, you might want to fly for a while with the as-shot paint finish, zits and orange peel and all  (What? You don't get any of that when you spray?) , then wet sand and buff out in maybe six months.
    I've used the WLS primer and found it to be great stuff, but it's beastly hard to sand.  I've also used PPG epoxy primer, with which I had some fish-eye problems (probably silicone lubricant in a syringe, but that's another story), then DuPont's Corlar epoxy, with is very good, and more recently, an acrylic urethane primer sold under the Transtar name and used commonly by auto body shops.  Both the Corlar and Transtar have good build, and are relatively easy to sand; these sorts of primers are often called primer/surfacers in the auto trade.  Both are compatible with common finish coats, both single stage and base/clear.
    Water-based paints sound good, but I'd be very wary of 'em.
 
    [BTW, another problem with flying in primer is that it's a bear to really, really de-grease the primer before proceeding with the finish coat.  If you've had any silicone products anywhere near it, like windshield goo that some folks like, or Lemon Pledge, which I've had recommended to me by certain factory personnel who shall remain nameless, you haven't a prayer of getting a good finish coat without a huge amount of work.
Jim,
 
Yes, the de-grease (Pledge, engine oil, exhaust stains, etc) was a bear.  If only I had had the painter put on another coat of primer after flying her for a year and a half.......  However, I sure would have messed up a paint job with the number of "experiments" that had to be re-worked, eliminated, etc.  Of course, these days almost all of the building mistakes have been exposed on the LML.  Oh well, things turned out pretty good even if I built the thing late in the last century.
 
Scott Krueger AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL (KARR)

A man has got to know his limitations.
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster