Hey, guess what I just found? I bought a new bottle of sanding sealer, same shelf as I have always gotten it from, at my local hobby shop - and guess what? Same label, same color, same design, even the same item number, except it reads "Midwest" instead of "Pactra". It's the exact same stinky stuff. Now, I still have the last bottle I bought from them, about a year ago and nearly a dollar cheaper. So I posted a photo of both jars to a.b.m.r.
Nearest I can guess, is that Midwest bought Pactra, or at least part of their product line, and the old stock is gradually being replaced by the new stuff.
So, we are talking about the same stuff, just now under a different name.
Ah, that explains why I remember "Aero Gloss" as a Pactra brand...
It's been a number of years since I actually did any balsa wood airplane stuff.
Someone mentioned a "Testors/Pactra" website... if they've slurped each other, I guess it's not surprising that they might consolidate/sell off overlapping product lines.
This has been an interesting thread that treatens to morph into another glue/finishing discusion. I doubt that using less wing dihedral is a good idea, but feel free to experiment. For reducing weight, I'd look first at the balsa. My original OT had reasonably light balsa, but sometimes heavy wood finds its way into kits. I finished mine with enough sanding sealer to provide a smooth surface, but I did not fill the deep grain. Filling the grain does not add much weight, except that most people do not sand each coat down the surface, allowing it to build up. I sprayed on a couple coats of white dope and applied the decals. The only thing I did to the glider to reduce weight was to remove the paper nozzel. And yes, the trim procedure works. If you do want more perfomance you can significantly cut the weight and drag of the boost vehicle. I typicaly had about one minute glide durations on B motors. I sill have my original OT, but I'd have to do some maintenace on the boost vehicle to fly it again. I also have the reissue kit, unbuilt, and looks true to the original except for plastic nose cones.
Don't use fill-n-finish on balsa. Find a woodworkers supply place and buy some lacquer sanding sealer. I use Behlen's in a spray can. It resists running, dries quickly, and sands easily. It does have a strong odor and you need ventilation. Once I think I have the grain filled, I apply a coat of Plastikote scratch filling spot primer to help show up any remaining defects and sand some more.
I trimmed the first glider and it flew fine, but when I tried to trim it to turn, I had to make some extreme elevon changes to overcome the dihedral. It didn't want to fly well that way, so I thought I'd whip out another one with 1/2 the dihedral and see what it does.
For reducing
Good idea. I'll go through the balsa scraps and find the lightest stuff I can.
I'm planning to make a couple of gliders to eek out longer glide times. I need a couple of gliders for smaller fields that I don't mind being heavy. That's why I'm going to fool with the dihedral and trim them to fly in a fairly tight turn. Having the wood lathe is perfect for a situation like this. I've already turned several cones and I'm ready to slap a few gliders together!
Filling the grain does not add
I think I will give the light ones a single coat of fill-n-finish and sand everything off except what is down in the grain itself, then give one or two coats of primer and sand them as much as possible before hitting it with as light a coating of white as possible to get decent coverage.
The only thing I did to the glider
I'm very disappointed in the booster nosecone. It was very out of round. I did a lot of sanding on it and it still doesn't mate with the body tube very well. I might turn a balsa cone for it too. Everything else other than the shock cord is top notch. I'm surprised how easy it was to build.
I'll try some Behlen's and some Midwest/Pactra sanding sealer as soon as I can get hold of them. In the mean time, thinned fill-n-finish is working pretty good for me.
I've been reading up on the Midwest/Pactra Aero Gloss deal the last few minutes. From what I've read, I believe that Pactra discontinued the line and Midwest bought the rights to it. I don't know if it was before or after the Testors parent company (RPM) acquired them. They have aquired/developed several name brands as can be seen on the Testors website. Unless I just missed it as I scanned the history of Testors on the website, they didn't even mention Pactra.
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