Thread Tools
Mar 21, 2016, 01:12 PM
Registered User
Managed to stop by the workshop and take a few pictures before and after final sanding. The LE turned out well, I just could have been a bit more careful when sanding off the skin, because in 2 or 3 small spots I did damage the 64 textreme.

I would summarize for myself to ideally take a 160 grit block to shave off the skin, and then a foam block with 800-1000 grit wet paper for smoothing the LE and removing the FG fabric structure, but ideally leaving the CF untouched.

Cheers, Georg

PS: wing weight should be 130 after joining the halfes.

Photos:
1 Before wet-sanding
2 & 3 After wet-sanding
Wing halfes
Sign up now
to remove ads between posts
Mar 22, 2016, 01:23 AM
Registered User
Nice. Thanks again for the info and pictures on LE.
Jan 17, 2017, 05:09 PM
Registered User

What's in the bag? Another Zone V2!


Well this thread seems to be in need of a little bump.

My first set of Zone V2 wings. All per Gerald's design, full chord 1.5m wing set, 2 panels.
I used 55g/m2 1K cloth which I got years ago, nowadays I can't find it anymore.

They came out nice and shiny and I am happy about the quality as it was my first bagging in three years. The leading edge needed some rework, I didn't thin the mylars enough. Also, at 138g the set is on the hefty side. Thing is I am just too slow with the entire laminating process, cutting the doublers and all, so by the time I get to remove excess resin, it starts to gel already.

But ey, they are real shiny, a big bling bonus over my tired Supergee disser wings.

Cheers, Andy
Jan 17, 2017, 08:44 PM
Aurora Builder
I'd be happy with those panels after a 3 year break! The secret to light wings is light fabric, 30-40gsm cloth, and light cores (my opinion, 25 psi foam is fine under 40gsm cloth for wings of reasonable aspect ratio, newer wings necessitate higher shear strength cores and/or vertical carbon shear webs).

Hot tip: cut all your fabricate before you have wet epoxy, then trim all at the root of the mylars in one shot.

Second tip: you can mix smaller batches of epoxy (1 per Mylar or 1 per wing half), gives you more working time.
Jan 17, 2017, 09:18 PM
Loving Lee's Slope Slut
JarheadFlyer's Avatar
Those look great!
Jan 18, 2017, 12:31 AM
Registered User
Sam,

I've got a choice of either 40 or 60 psi foam. Wing will be wider than the Snipe but not a full Zone V2 chord. What would you recommend for surface and spars (anyone chime in).

Will be a bagged wing.
Jan 18, 2017, 05:54 AM
Registered User
cn0rris's Avatar
My most recent wing was Carboweave, and I think I'm in love. It handles better than most other fabrics in my opinion, and you can build light and strong. It's more expensive, for sure, so definitely built with something cheaper until you've got solid fabric handling skills and are starting to feel more confident.
Jan 18, 2017, 05:59 AM
Registered User
cn0rris's Avatar
Dotcom, a third tip (Sam's are spot-on) is to share the work with a friend. More hands definitely makes it quicker. Plus, that friend typically wants their own wing, so you get to "turn the crank" more times and develop your skills faster.
Jan 18, 2017, 10:16 AM
Aurora Builder
Quote:
Originally Posted by cn0rris
Dotcom, a third tip (Sam's are spot-on) is to share the work with a friend. More hands definitely makes it quicker. Plus, that friend typically wants their own wing, so you get to "turn the crank" more times and develop your skills faster.
+1 to that. Lightest wing I've ever built (~100g, all glass and 25 psi foam, could take a decent launch, durability, not so much) was built with two hands.

GaryO, my recommendation is the 40 psi foam, utilizing a double spar system. I run a 4.1oz uni carbon from Soller Composites, 15mm wide at the root, tapered to 10mm at the tip. I may go a little wider at the root, maybe 20mm, if you are concerned; its not much weight added for a bit of piece of mind. Align the tip of the carbon spar with the location for the throwing blade, so forces are transferred directly. Along the hingeline, wing side, I've been running this tape cut in half top and bottom (10mm wide strip): http://compositeenvisions.com/textre...roll-1127.html

The other key to my spar system is a 1k carbon sleeve over the foam core I cut out of the wings, about 8mm wide foam section sliced out both halves completely. This gets wrapped with the carbon sleeve and formed into one section (joining the wing halves, this is done in joined molds). This section extends beyond the servo well in the wings some, reinforcing this critical area. One could do this in a bagged wing, or any wing, by splitting the core in half with an x-acto underneath the middle of the spar, then wrapping the forward section with some 1k cloth or carboweave (the latter is probably completely sufficient, even in the thinnest of wings, and will leave less protrusion from the surface). Trick is getting the back half and front half re-aligned, my advice is to 3M the lower spar to the core and using that as a bit of a hinge. The other trick is you want your uni carbon spar to contact this carbon vertical shear web directly!! This isn't the easiest spar system to build but it will result in a spar that is very light and very strong, since you are using the carbon to carry shear forces and not the foam core (which generally buckles->spar failure->wing failure). This would also let you use a very light foam core, but I think the 40psi foam is a little more durable than the 25 psi foam and not too terribly heavy. I'm also fairly convinced that the thin wings needs this level of reinforcement, Tom would know more as he had to completely revisit his spar system on the NXT to prevent failure.

For doublers, in a light wing the 40gsm cloth is okay, I prefer the 64gsm textreme or 1k carbons for throwing blade doublers (its thicker, so a fair bit stronger). My throwing blade installs with light doublers all fail eventually, probably do to poor launch and trying to get the blade outboard too far.

Pre-facing: needed. Kevin Sharbonda has some great photos of how he does his in a bagged wing. I think the CW works well here. I'm forgetting what I have in the wing I'm building up, I know I built some wings with a 1k carbon wrap on the aileron face then the CW skins come across that, forming what is arguably the stiffest aileron out there, despite only using 25 psi foam in the wing!

I'll also add that the spar system I detailed above is stupid stiff. Like I'm still impressed when I handle this wing how solid it is, despite the 115g all up weight for a 344 in^2 wing!! Solid carbon rod or flats may be stronger in the event of a crash, but more effort to channel the foam for marginal gain IMO.
Jan 18, 2017, 10:27 AM
Closed Account
Quote:
Originally Posted by GaryO
Sam,

I've got a choice of either 40 or 60 psi foam. Wing will be wider than the Snipe but not a full Zone V2 chord. What would you recommend for surface and spars (anyone chime in).

Will be a bagged wing.
I agree with Sam that the 40psi will hold up but I find the 60psi is easier to work with. The Epee wings are done with 40psi foam and they take some serious abuse.

The 25psi foam ideas that Sam loves do make sense except for one thing. I HATE working with it. One slip with any tool and the core is history. I understand that with a larger wing the weight difference can add up but working with 25psi is slower for me because I have to be so gentle with it.
Jan 18, 2017, 04:28 PM
Aurora Builder
That's a fair point Paul. I can get away with more error on the 25psi cores because I am compression molding, so have a ~0.020" to play with before I get a dry spot. Also, the only thing I am doing is slicing the flaperon free, cutting out the root chunk, and putting the wire channels in. Everything else gets done by the CNC (once you have one and learn to make full use of it, you won't go back).

In general, 40psi XPS makes the best all around core material, after Rohacell IGF31 of course, but when you add price in, XPS wins
Jan 18, 2017, 06:15 PM
Registered User
Wow friends, what wealth of information! It seems that since my last build a lot has moved...
I still need to run the exact numbers on my wings to determine the resin fraction, but a lot seems clearer already:

Skins: light skin tissue is certainly a key factor. I read a lot about Carboline and Carboweave. I also found 43g Samurai Spreadtow on which i did not find much with respect to bagging , has anyone tried it? It is uber pricey though. I really like the looks of spreadtow and in my neck of the woods all DLGers fly Snipes and FW6 which have the Carboline, so a spreadtow wing would be a welcome change to set the homebuilds apart.

Facing: all my facing is done with 49g glass applied with 3M924 tape. For the leading edge I should certainly consider carbon also. When you suggest CW which weight do you use?

Doublers: 160g carbon was used for the tip, blade and flap horn doublers, reasoning that these locations need thickness to allow some bite against the blade and horns...with a lighter carbon I may win another few grams.

I already look forward to bagging the next set
Andy
Jan 18, 2017, 08:18 PM
Aurora Builder
Andy: the carboweave is really nice to work with and you can get it stateside. The 43gsm samurai spread tow is a pretty new fabric, not sure if anyone has built with it yet.

You can use the 40gsm for leading edge wraps or 30gsm. I also like using Kevlar on the leading edges, that makes for a bomb proof wing but does add weight.
Jan 22, 2017, 03:45 PM
Registered User
While I'm mulling over the wing layup one thing I did change was the fuselage layup, from previously 47g I reduced to stellar 39g and whats more important the fuse CoG moved significantly forward. I will see if it is also up to the loads...

Next up will be some tails until I take another shot at the next wing.

Andy
Jan 22, 2017, 04:23 PM
Registered User
cn0rris's Avatar
Are you willing to share your fuse layup? I'm collecting information about this - starting to think about making a fuse mold. Newer materials are really allowing lighter, but still sturdy layups…

Quote:
Originally Posted by Dotcom
While I'm mulling over the wing layup one thing I did change was the fuselage layup, from previously 47g I reduced to stellar 39g and whats more important the fuse CoG moved significantly forward. I will see if it is also up to the loads...

Next up will be some tails until I take another shot at the next wing.

Andy


Quick Reply
Message:

Thread Tools