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Not sure if this is an appropiate thread title or not, but I have been doing a little experimenting with fuse bagging and wanted to share.
Basically, I am fiberglassing, and adding a little carbon to the inside of both fuse sides on my Q500 Seekers. My first attempt came out quite heavy, as I used a lot of carbon 2.4 oz fabric.
This go around I tried to go as light as possible. I started with a solid 1" thick, straight board which I wrapped with Coated freezer paper (please test your epoxy with the coated freezer paper, some will stick, most will not). I took both inside fuse halves and laid up 3/4 oz fiberglass to each half on top of the freezer paper (epoxy and glass up). After the glass was wet out and scraped nearly dry, I added some CF laminate (.007) to the rear just in front of the tail for strength. I then lined up the 1/64" ply doublers and carefully placed them perfectly over each fuse half. Once everything was scraped and lined up well, I put down a layer of perforated peel ply, and then some breather cloth. The perforated peel ply allows the epoxy to be pulled through the holes into the breather sucking up nearly all of your excess epoxy.
Try to use as little epoxy as possible, if you use too much near the alignment slots or edges it takes more time to clean up the halves after everything is dry.
I then placed (in this order) the wood board, with coated freezer paper, the wood fuse sides, glass, epoxy, doublers, CF, Peel Ply, and breather, into the bag and sucked as much pressure as my pump could pull (about 20" of mercury). If you want to save your breather cloth for future use, you could substitue any of the "better/thicker" paper towels available.
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After I cleaned up the edges with sandpaper, and cut out the alignment tabs with a xacto, I put them on the scale and measured in grams.
This is both fuse sides after glassing at 54 grams.
The second picture is two fuse sides and doublers not glassed. I weighed 3 differenet sets of fuse sides and doublers, and all unglassed kit sides came in between 46-48 grams.
Bottom line is that I added no more than 6-8 grams and SIGNIFICANTLY added to the stiffness of the fuse sides. Well worth it in my opinion.
Thoughts???
< Message edited by daven -- 3/28/2006 5:03:31 AM >
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Joined: 12/7/2001 From: Andover,
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Here is the final product.
Alot stronger, with not much work. I originally was just looking for a way to get away from using CA to glue the doublers down because of bad allergies I have to it. I am quite pleased with this fuse, just wish it was for me.
< Message edited by daven -- 3/28/2006 5:04:07 AM >
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quote:
ORIGINAL: daven
I am quite pleased with this fuse, just wish it was for me.
That's the kit bidness for ya.
Just one question: Do you find that the pre-laminated fuselage sides are hard to bend when gluing them to the formers? Seems like to really pre-fab them, you'd want to use a form that presses them into their final shape as the epoxy is curing ... especially if you're trying for that "Coke bottle" effect in the aft section.
But, notwithstanding any of that ... looks great! Thanks for sharing!
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Duane, I don't use a "coke" bottle design like many others, it pretty much shapes itself on the location and width of the formers. I don't remember the last one being an issue, the tabs on the formers and tray pretty much straighten everything out. I haven't built a "banana" since I started using the tabs and slots.
I really like your idea of baggin it against a form in the exact shape of the fuse. However, that would be a little trickier. I'll have to noodle that one over.
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This is much easier than building a hollow composite wing, but that is where the building idea came from. I've been building hollow composite wings for a couple years, and really find little enjoyment in that process. I have one started that I hope to finish in a week or so where I used no PVA and tried a little painting in the mold with wax only. Actually, molded wings would be funner if you weren't constantly trying to cut weight.
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Joined: 8/26/2002 From: Decatur,
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Thinking out loud here. Why not use a little heavier glass - 3 oz or so - and leave the 1/64 ply stiffeners off the sides. Seems like it would be one less step, maybe a few grams less weight and have the same end result. The end result being a stiff fuselage. Put the glass on the bias. I make spars for wings out of 1/8" vertical grain balsa, bag with 2 layers of glass on each side of the balsa. 1 layer on the warp & weave, the 2nd layer on the bias. With using peel ply to soak up the excess resin, it gains very little weight and makes an amazingly strong piece of lumber. brad
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Not a bad idea at all Brad. Dropping the 1/64" would be fine with me, its one of the more expensive cut parts of the kit.
I fit the formers and servo tray tonight and cracked the fuse at the rear former squeezing it all together. I'm really not sure if I can use the right side, pics to come shortly.
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Fuse Bagging - 
