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Old Apr 08, 2006, 12:53 PM
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Portland Intl, Oregon, United States
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Looking really good so far.
I have just spread PVA over the plug with a foam brush or even just a piece of foam.
Goes on wavy but as it dries it smooths out very well..

Keep us posted, this is a good thread to watch

TIM
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Old Apr 08, 2006, 01:57 PM
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I used a paper towel to apply PVA on smaller molds with success.
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Old Apr 08, 2006, 02:39 PM
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Roseville, California, United States
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Quote:
Originally Posted by Reed
Hey Hutch, nice work.

My idea for the little ridge on the mold includes grinding out the canopy area of the mold so that you can still get in and do a wet seam layup. Just leave a little lip where the rise/ridge would go. See what I mean?
Thanks Reed! That is what I was hoping to do. So after I mold both sides and remove the plug (hopefully) from the mold I was planning to cut out the area where the canopy will go. Then I can build the canopy lip using either yours or Timís method. Voilla!

Quote:
Originally Posted by blewis01

Question, what are you using to spray the PVA? Cheap airbrush?

Bruce
I bought a new airbrush the other day, but I don't have a compressor here or the valve attachment that connects to the propel cans. Guess I'll have to figure out that part some other day. For the canopy mold I used a paintbrush to paint the PVA on. I was pleasantly surprised when the brush strokes eventually faded away to a nice shiny surface. For the fuse mold though I wanted to try spraying the PVA on. Since I have to make a stop at Tap for some woven roving anyway, I figured I might give this thing a try and save my new airbrush for painting....

http://www.tapplastics.com/shop/product.php?pid=173&

I really want to just go flying though!!!

-hutch
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Old Apr 08, 2006, 09:03 PM
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Ahhh, nothing like a little stick time to clear away the rainy day blues. Pretty much had the place to myself today down at Sunset Beach. 15-18 straight in. Not epic but a fun fix!

I picked up my sprayer and heavy fiberglass today too. Ready to go! Should I wail till just before I'm ready to start with the epoxy to spray on my PVA, or would it be ok overnight If I end up painting the town red tonight?

-hutch
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Old Apr 08, 2006, 09:07 PM
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I was also thinking about my layup for the mold. What I had in mind was the following:

1 Layer of just epoxy to cover the plug and parting board.
4 layers of 6 oz glass after the epoxy jells.
2-3 layers of the heavy 10 oz woven roving.

That sould get me pretty close to a mold that is around 1/4" thick I would think. Sound good?

-hutch
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Old Apr 08, 2006, 09:18 PM
that's gonna hurt...
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Quote:
Originally Posted by Hutch
Ahhh, nothing like a little stick time to clear away the rainy day blues. Pretty much had the place to myself today down at Sunset Beach. 15-18 straight in. Not epic but a fun fix!
-hutch
Dude I am jealous - I've been stuck here all day waiting for Fed Ex to deliver the 'nana. 6 PM and no Fed Ex guy yet. I was working outside thinking I should be flying today!

Your layup sounds good - only one thing I'm concerned about, but I think you are OK. I have heard that you should put a light layer of glass against the plug to minimize weave "print through" I think it's called. I think you are OK because you are putting an epoxy layer and letting it gel. If you decide you need some light glass, I can help you out with some 1.5 oz.

Bruce
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Old Apr 08, 2006, 09:47 PM
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FWIW, I've bought airbrush stuff from these guys and been happy with it. So far, spraying the PVA has worked great for me.
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Old Apr 08, 2006, 10:19 PM
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Thanks for the site Reed! The one I got the other day is a Badger Anthem #155. Dual action and all that. I guess I need to get a small compressor though if I want to do quality airbrushing. Any suggestions there?

Bruce! I hope your naner finally came! What a long road that has been. Did Aaron get to maiden the P-51 today?

-hutch
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Old Apr 08, 2006, 10:52 PM
that's gonna hurt...
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Hutch - the 'nana came about 15 minutes after my last post. Aaron's P51 is almost done, he backed off after the damaged 'nana arrived last week, knowing I wouldn't have a plane ready until the replacement came. Pictures going up on BayRC next.

Good luck on the mold. Don't know about the compressor as I have a full size one in the garage. Haven't been there for a while, but D&J used to carry a lot of airbrush stuff, mostly Badger and Pasche.

Bruce
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Old Apr 08, 2006, 11:11 PM
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Hi HUTCH,
your layup is OK but I think what Bruce said about the light layer first would be a good idea. I put on epoxy mixed with carbon powder first then let that gel just till slightly tacky. You might even want to mix up a little with cabosil in it to go right where the plug and parting board meet, so you dont get air bubbles there, and also around the tail cone too(where ever there are tight corners etc). Then a layer of light glass cloth with regular epoxy, and then let that gel and then start adding the heavier layers. If you dont let it gel sometimes the glass cloth gets pulled away from the plug in tight corners etc. and that leaves voids in the mold. The light layer of glass will follow all the little intricate curves etc in your mold better than the 6 oz will. Tap sells a 1.5 oz that works good for me.
Also after you put on the last layer of that heavy glass cloth you might want just one more layer of the 6 oz or even the 1.5 just to make the mold a little nicer...

again, these ideas are just the way I do it and maybe not the best way...

good luck

TIM
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Old Apr 09, 2006, 02:04 AM
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Quote:
Originally Posted by A6INTRUDER
Hi HUTCH,
again, these ideas are just the way I do it and maybe not the best way...

good luck

TIM
From what I have heard of your Pica, If I can get close to what you were able to make I will be happy!

-hutch

P.S. I have a bunch of really light glass on rolls so I will use that as a first layer or so as suggested by y'all. Thanks for everything to all that have helped me out here, I'll keep you posted as tomorrow rolls along.
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Old Apr 09, 2006, 02:33 AM
more casual than stylish....
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Question to the mold-gods...

When you are laying up the mold, and you continually add layers to it, are you mixing additional batches of resin, or is the hardener slow enough that you can keep using the original batch?
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Old Apr 09, 2006, 03:31 AM
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Quote:
Originally Posted by slopemeno
Question to the mold-gods...

When you are laying up the mold, and you continually add layers to it, are you mixing additional batches of resin, or is the hardener slow enough that you can keep using the original batch?
Not a mold god....more of a mold trainee, but the way I understand it is that if you are using epoxy (as opposed to polyester) you can lay new layers on with fresh epoxy as long as the previous layer has not fully cured yet. If you wait till the first layer has cured you will pretty much have two layups that are glued together instead of one monolithic piece.

I have absolutely no experience with polyester resins though so it may be different with those.

-hutch

Did you get any flying in today? Light or not, it sure was nice to get some sun!
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Old Apr 09, 2006, 11:09 AM
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Thats how I understand it to work too.
As long as the cure is not complete you will get a good bond when adding new layers.
Letting it tack up betwee the first few layers will insure that you dont get air bubbles and layers getting pulled away from the plug as new heavier layers get added.

Yes new batches of epoxy need to be made as you go because the epoxy will go off rather quickly in the mixing cup, so by the time the original layer has tacked up the remaining epoxy in the cup will be done. When epoxy is spread thin it takes longer for it cure than it does if it sits in a cup. So try to mix only enough for your imediate use so you dont waste too much....

TIM
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Old Apr 09, 2006, 12:37 PM
more casual than stylish....
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Great answers guys, thanks. And dont sell yourself short Hutch, that thing looks amazing.

YES, its true. I flew, and I actually got (a hush falls over the crowd..) A TAN!
Turns out, that IF the sun shows thru the clouds and you can stay out in it long enough, you skin actually takes on this sort of golden hue. Neat!
Sharkbait and I went to Hamilton Field to maiden his electric Lancair, then we went out to Tick Pt and he maidend a Wildwing. It was light, from the SW, but fliable.
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