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Old Aug 30, 2012, 06:11 PM
G_T
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Well, I pulled the fuselage from the hatch mold. The concept seems ok. One cannot tell the start and end of where epoxy was added, and it certainly looks better than it did before I started this process. However I didn't use quite enough epoxy. A tiny bit must have soaked in. No excess collected anywhere that I could find.

So, we're headed for round 2! PVA is drying on the mold... I'll use a little more than I think I need this time. We should know how this attempt works in the morning.

Gerald
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Old Sep 01, 2012, 12:24 PM
G_T
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It took 3 rounds actually. What I figured out is that one needs to let the epoxy reach a somewhat jelled stage before sticking it in the mold. Otherwise, it wicks away via capillary action and simply puts a thin coating over the surrounding region. When it is thicker it cannot migrate away the same way. Now the result is about as perfect as it can be. One can tell with careful inspection where the migration region stopped, but it is not noted at a casual glance. The fuselage looks much better than before I started the cleanup attempt. The fuselage is no longer a second!

Gerald
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Old Oct 10, 2012, 12:29 PM
G_T
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All fuselages from batch#1 have been shipped. I'll be making one more, but that one is for myself. I still haven't kept one and I want one around for reference if nothing else - though I do plan to fly it.

I'll be starting prototyping batch#2 in a few weeks. I've acquired most of what I want for fabric - at least enough to get by for a little while.

There will be some changes for batch#2. Here are the plans:

The front screw becomes a titanium screw - I have these on hand now. It took longer to get them produced by about a month than I expected. The rear screw stays anodized aluminum. The steel hardpoints stay, but I may try to lighten them a little.

Kevlar inside the tailboom stays - but it will be a different Kevlar, lighter than the 1oz that I'm using now. Woven, and unobtainium. It is old stock Russian and I bought what there was of it.

Samurai fabric instead of the 1K 16x16 outer carbon that I had been using. It has a higher modulus and lower weight. The result of these last two changes should be to lighten the tailboom, moving the fuselage CG forwards.

Other changes are uncertain at this point. There are too many pieces of fabric in the fuselage and that really slows me down. I need to simplify somehow, but I don't want to give anything up in the process.

--- Things less certain ---

I'm not getting rid of the current molds, or consigning them to the dust bin, but...

The current fuselage was designed for the Edge-4P and -2P planes. Except for Seba, and the JJEdge, I don't think such wings are available. Other wings are usually not too bad a fit, if one shuffles the wing a little forwards or backwards for the best fit. Then one needs to do a little filling. This is not ideal of course. The Synergy wing likely is the worst starting fit.

I'm considering producing a different fuselage. It is still in the brainstorming part of the process, and I may not do it. Here is what I'm thinking:

Corian molds. Cleanup is much easier. They won't take much heat, but I'm not post-curing in the mold anyway. I remove before post-cure. The mold would be lighter and smaller - easier to deal with. Overall this change could save me about 30 minutes per fuselage, which explains why I'm interested! But chances are the parting plane might not be quite as good. That would remain to be seen. Not being as good really would be a feature from a manufacturing perspective. I wouldn't have to have the molds cracked open for the first half hour to get epoxy out of them.

Very slightly ovalize the boom. This might let me remove two strips of unicarbon. It won't really provide a weight savings but would save some cutting and layup work.

Rotate the nose 90 degrees, so equipment is flat rather than vertical. This automatically stiffens the nose due to the geometry change. I think this would allow the carbon to Kevlar transition to be farther back, which would improve the degree of 2.4 friendlyness.

--- Things unknown ---

I do have some temptation to go back to pod and boom construction (pre-joined, of course). It would be easier and faster for one thing. Properly done, the weight penalty can be very small. Fabric can be used more efficiently as well.

If I go with a different fuselage, what wing should I make it fit best? Or should I average things so nothing fits perfectly but nothing needs much in the way of filler? Should it be an existing wing or should I design a whole new plane?

Feedback/thoughts appreciated! Again, I may just stick with the existing design. All this is TBD.

You guys are the customers - what do you want?

Gerald
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Old Oct 10, 2012, 12:45 PM
Chuck 'Em and Chase 'Em
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Love the topic and all your information and thoughts Gerald. Very inspirational and super informative.

As for changing things, how much room do you think you have to make a 'better' wing as you say for this new fuse? I think lots of pilots love the Edge and Zone V1/V2 wings and I can only guess (since I have not followed it much) the Synergy as well.

Personally, I know building season is coming but at the same time I know you commented that you have not flown much in the recent past. Do you have plans to fly more? Maybe that should decide as to how large a project you wish to undertake.

I was always told, if it is not broken, don't fix it. Maybe you should get proficient with what is out there and prepare to fly more.

Now if you feel you can get yourself setup witha few planes for next year AND do all this design work, I can guarantee we love to have you at the field and at the drawing board, if possible. to me, I can say it seems you have sacrified the field for the drawing board. If that is what you enjoy, please keep on doing it. I knowI have enjoyed the edjucation.

I guess what I am saying is prepare to do what you enjoy doing next year and we will all live with it. I have come to say this only because my father has gotten older and never really learned to fly. He now has back issues and seems to be hunched over all the time. I feel his flying days might be behind him to some degree. He has been interested in flying wellbefore I was born back into the 50's. Now, he might have to give that up.....


Thanks for all the hard work over the years. Whatever you do, we will apreciate it......

OK, all of you can flame me now. Flame suit on.

Frank
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Old Oct 10, 2012, 12:55 PM
Aurora Builder
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Gerald,

I have been contemplating what to do for a fuselage design myself. Most of your less certain changes I would implement, namely the fuselage rotation and the oval boom. On the fuselage rotation, I would make sure 2x DS285's can fit flat on the fuselage floor.

Less sure things I am thinking about are the following:
1) 4x servos in the pod-worth the linkage geometry hassles?
2) Wing pylon-give you more wing options, as pretty much everything fits but requires the builder to modify the wing hard points.
3) Integrated stab mount. Lots of pluses and minuses. I've concluded very few people are using full-flying stabs these days (I would say 3-4 on the East Coast).

I would like the Zone v2 wing to fit directly. That is the most common wing being built by homebuilders IMO. The pylon mount eliminates concern over wing airfoil.

Otherwise, design a complete ship. I think you would enjoy that and be happy.

-Sam
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Old Oct 10, 2012, 04:50 PM
G_T
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Quote:
Originally Posted by Fly2High View Post
... As for changing things, how much room do you think you have to make a 'better' wing as you say for this new fuse? I think lots of pilots love the Edge and Zone V1/V2 wings and I can only guess (since I have not followed it much) the Synergy as well.... Frank
Well, I can give you partial answers.

I do really like flying the Edge. But Edge is difficult to make a good enough wing. Also I've seen plenty of evidence that the wing performs better when the surface is not quite as smooth. It would be a good candidate for a dry layup without clearcoat, except perhaps keep the front couple of inches shiny. Topside that is, on the bottom keep it smooth. Edge also is an average launcher. It is not all that hard for me to improve Edge launch. The blends are also not as good as I would like. Edge root is very good; tip is very good, but the blends are only ok. More is possible if the blend is simply replaced with a good but appropriate foil.

Zone-V2 is currently rather popular. I have little stick time on it, but I found it fun to fly. My understanding is that it isn't as happy with ballast, though it rarely needs it. So increasing the ability to carry weight would be one place to attack. Another is reducing the pilot workload - that is always of benefit. Or reducing the sink rate while keeping the launch height. Right now I see a possible Zone-V3 as a slight refinement of Zone-V2, based on the experience and feedback from those who have flown it. I would expect flight behavior changes to be subtle - certainly more subtle than the differences between Stobel V3 and Stobel V2.

Synergy was a first shot for me of another development methodology. I expect I could do better with enough work. However there isn't enough pilot feedback and contest experience with this wing to be sure what changes would be most beneficial, so I'm holding off making any changes. I had hoped / expected that there would be more of them flying by now but this isn't the case. Synergy has different flying characteristics than most high performance planes. Tom's TS wing is very interesting but it has Blaster-ish area which is beyond what most can launch most effectively. Probably too much area there for the average pilot. I enjoyed flying Tom's a little when I had the chance at CASA. I have one of the wings but no plane to attach it to at the moment. I plan to build it and fly it to get to know what it does in the real world. But it is a different aspect ratio and that does change things somewhat.

I've certainly done work towards Edge-V2, Zone-V3, and Synergy-V2. Edge would likely see the biggest change if I completed and released it. But in any event, I don't have plans to release anything revolutionary for next season, but instead to take one of these and refine it a bit more.

Gerald
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Old Oct 10, 2012, 08:33 PM
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Gerald,

Synergy to me, just seems to large. I'd think a key element in glide performance for still air is weight. At the current area, it would be difficult to build a light plane.

Since less area usually translates to less drag, it should also launch higher, I'd speculate.

I haven't built one, just can't get enthused about another Blaster 3 or wide wing Encore size plane. Now if it were somewhat smaller than the current ZoneV2 wings ...

Just speculation.

Gary
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Old Oct 10, 2012, 11:46 PM
G_T
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The reference Synergy design is not that large. What you have seen is the TS wing, which we enlarged quite a bit to get it to be floatier at higher altitude for the Team Select. The Synergy wing has about the same area as the other wings I've published.

Gerald
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Old Oct 11, 2012, 12:35 AM
Team Hong Kong F3K
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I have a Synergy wing drawn up to compliment my ZV2 planes, but haven't had time to test yet. Hope to get to it later this year with some feedback.

Thomas
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Old Oct 11, 2012, 02:24 AM
G_T
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I'll be rather interested in what you think. Even from my very limited stick and visual time, I can safely say is very different from Zone.

Differences I've seen:

Zones of all stripes like camber and can use lots of it if one wants. Edges don't like lots of camber. Synergy doesn't like lots of camber, very much like the Edge.

Synergy is slower, though that could be the TS wing fooling me. Others have said the same thing with different wings though, so I think it is a safe statement.

To make Synergy go fast, you have to mean it. What I mean by this is that a Zone is fast and easily goes fast. With Synergy, you put it into speed mode, but you also have to push on the elevator to get it moving. You might have to hold the down elevator to keep it moving. But when moving it is pretty fast and pretty flat.

Gerald
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Old Oct 11, 2012, 08:06 AM
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Gerald,

Instead of responding to this thread last night I took the liberty of preparing my molds for another pull, you need a ZV2 wing.

I'm expecting Synergy cores by Christmas (I know, 2 months away but CNC software is painful). You will have a wing from this batch of cores (think Orange Taboo).

We've talked a fair bit about this in the past. My suggestion is to build something YOU will fly. I interpret a lot of passion for the Edge in your writing. I see Edge as a design that requires a lot of advanced techniques to build and fly right. Something that you could charge a fair price for if you built say 10 planes. I think developing Edge-II, and a plane based around that, perhaps build and fly it for 6 months to a year before you release the design, would be a very satisfactory effort.

-Sam
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Old Nov 01, 2012, 06:06 PM
G_T
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Hi Sam,

I'd love to have one of your wings! THANKS!

-----

I screwed up another fuselage last night. This was the end of the material I used for the first batch so there won't be any more like it. Hopefully the second batch will be better though! In a few weeks I'll start to do a little layup testing and all that sort of stuff.

Anyway I came up with another way to screw one up. Seems like there is no end to the possibilities. I think that is what makes fuselage work so annoying at times. Too many rejects for the level of work.

My epoxy bottles were on the low side, so I topped them off. They are labelled, but, I put the hardener bottles back in swapped positions. When I went to make the fuselage, the first batch of epoxy smelled a little stronger and looked a little darker, but I just chalked that up to aging hardener. It did seem to be thickening up a touch faster than usual by the end of that batch. Then I went to mix up the second batch... The light came on "that's not right...". Read the label, and $@#@. I used all fast hardener for the first batch! It was MGS, so perhaps not all is lost. Tossed the second batch, and made a third but using slow hardener. I finished the layup, but this time used 60psi for the initial evacuation stage instead of the more usual 45. I'd hoped to squish more epoxy out.

Didn't matter... The fuse looks very good, one of my better looking ones actually, but it is somewhere around 8g heavy. That's not good for a DLG. What a waste.

So if someone wants an overweight DLG fuselage for a beater or a light sloper, first $80 + 15 shipping, continental US, gets it.

What a waste.

Gerald
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Old Nov 01, 2012, 06:35 PM
Thermal, where art thou?
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Quote:
Originally Posted by G_T View Post
Hi Sam,

I'd love to have one of your wings! THANKS!

-----

I screwed up another fuselage last night. This was the end of the material I used for the first batch so there won't be any more like it. Hopefully the second batch will be better though! In a few weeks I'll start to do a little layup testing and all that sort of stuff.

Anyway I came up with another way to screw one up. Seems like there is no end to the possibilities. I think that is what makes fuselage work so annoying at times. Too many rejects for the level of work.

My epoxy bottles were on the low side, so I topped them off. They are labelled, but, I put the hardener bottles back in swapped positions. When I went to make the fuselage, the first batch of epoxy smelled a little stronger and looked a little darker, but I just chalked that up to aging hardener. It did seem to be thickening up a touch faster than usual by the end of that batch. Then I went to mix up the second batch... The light came on "that's not right...". Read the label, and $@#@. I used all fast hardener for the first batch! It was MGS, so perhaps not all is lost. Tossed the second batch, and made a third but using slow hardener. I finished the layup, but this time used 60psi for the initial evacuation stage instead of the more usual 45. I'd hoped to squish more epoxy out.

Didn't matter... The fuse looks very good, one of my better looking ones actually, but it is somewhere around 8g heavy. That's not good for a DLG. What a waste.

So if someone wants an overweight DLG fuselage for a beater or a light sloper, first $80 + 15 shipping, continental US, gets it.

What a waste.

Gerald
I'll take it .. if you tell me how much it weighs. Might come in handy as a pre-ballasted stormbird.

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Old Nov 01, 2012, 09:19 PM
G_T
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I'll finish it up in the next few days then I can get you an accurate weight. I need to cut the hatch opening and make a hatch.

Gerald
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Old Nov 03, 2012, 01:21 PM
G_T
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PVA cleaned off and screws installed, but the hatch opening isn't cut yet and the hatch is not trimmed. So it should end up gaining perhaps 1g from where it is now. Were it one of my planes, I'd be cutting about 2.4" off the tailboom. You don't have to of course - I just prefer the booms not as long as some. That would remove perhaps a couple of grams. Current weight is 47.4g. So I expect the final weight to be somewhere in the neighborhood of 48.5g before any trimming of the tailboom.

Gerald

PS - Send me a PM with your address. Usual rules - don't send payment until you have inspected it and decided to keep it. Otherwise just send it back. I may get it shipped on Monday.
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