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Old Sep 02, 2005, 01:53 PM
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Dave North
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USA, CA, San Jose
Joined Apr 2004
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A Few Additional Points For The Builder

There may be a few more things the discriminating builder might want to know about this design before starting (or even buying).

A typical 'overbuilt' shockie will have an airframe weight in the area of 3oz. You should be able to hold this airframe under 5oz, but 4.5-oz would probably require unobtainium. (I wish more reviewers would include the stripped airframe weight. Trying to work backward from final weight by subtracting various components is unreliable).

Though it's slightly larger, the primary reason for the extra ounces is probably the choice of foam: rather than depron, it uses something more like foamcore. The exposed interior material is relatively brittle, but the coating is superior to typical foamcore (stronger and lighter). This does mean the graphics print well. On the other hand, it's very easy to mar the flatness with a fingernail (virtually no 'bounceback').

There's more carbon (much of it tube rather than flat) and heavier wheels, which also contribute to the weight issue. The rod in the fuse will be appreciated by many, and may be worth the weight. (Caveat: rods that go directly behind the motor can sometimes save a plane's nose at the cost of a motor shaft or bearing. It's your choice). But it's best to bear in mind this is not a lightweight foamy at all; more on the clunker end of the scale for its size. Choose motor and battery accordingly, but don't assume your CDROM setup will crank this pup like its lighter cousins. What effect the weight may have on flight performance is untested by me, but I can't recall seeing a 3-D foamy ever fly better by adding weight.

Though much is made of not requiring tape (it is recommended to use some during the build, then remove it) the hinging system is far more difficult to install than just taping the surfaces on. Over 20 little tabs have to be glued into various surfaces -- and the method suggested by the instructions will almost certainly result in misalignment (not of the connections, but of the tabs themselves inside the foam -- or protruding, as the case may be). You'll probably have better luck just slipping them in between the coating layers, then sliding the tube in to align. One welcome result though: no sanding bevels on the control surfaces. Good thing, since the foamcorish material is not easily worked. You will be required to sand the fuse support bevels.

Using CA is probably not a good idea at many stages, particularly where fit is shaky (many of the foam parts will require bracing to make full contact, particularly the bottom of the fuse. If your glue set before you got the tape -- or whatever method you like to use -- in place, it wouldn't be pretty). The instructions mention alternative glues can be used, but there are no specific suggestions. White glue (canopy glue) works well in places, as does either UHU or even some spare GWS glue. In others, foam-safe CA will be okay. Again, some thought is a good idea.

The tabs and plastic parts are molded from a flexible, somewhat sticky material. Seldom will the parts fit properly. Trying to insert "z-bend clevises" will probably result in some breakage -- fortunately plenty of spares are included. However, the fit is so snug, and the material so sticky, that the clips and control horns will put considerable drag on the servos. (Some mitigation can be achieved with lubricants such as wax bicycle chain lube, but not enough. You should also plan on sanding and reworking them to try for a looser fit to allow free movement). Though relatively small servos can suffice on a typical tape hinge, they may not cut the cake here. Figure on more weight because of that.

Extended servo arms are included for JR, Hitec and (?) Futaba servos. That's another reason you may have a problem with this plane if you prefer something lighter -- all the recommended servos are in the older, heavier mold. HS50s might cut it, but I have my doubts.

Almost nothing is quite the right size, so don't assume things will "just fit." They often won't, though they're usually close. You'll probably have to trim a bit here and there, and do some sanding. Assuming things will work out can be anywhere from annoying to disastrous: for example, if left "as stock" the rudder would not turn (the retainer clearance slot had to be moved). Try _all_ parts carefully before assembly, and think it through.

Blindly following instructions will confuse. For example, in one picture the wing Trailing Edge is clearly marked "Leading Edge." Sad to say, though, they're no worse than most instruction sets out there, and better than some.

The hinging system is interesting, and with further development may turn out to be a good idea. However, it's not quite what you might expect from the review. For example, it's indicated you could snap the elevator off for subsequent repair or replacement. But the elevator is also constrained by the rudder mounting tube, which is glued onto the plane -- snapping off the elevator requires literally ripping that tube off also. But wait, there's more: the control rods are glued on both ends, meaning the removal of _any_ control surface will require breaking this joint or removing the servo arm (topologically impossible on the ailerons) or using a different system in the first place (probably a good idea). Also, the rudder holds the tail wheel, but it's stuck over the mounting tube -- popping off the rudder without ripping off the tail wheel is a challenge!

It may be a bit misleading to say these surfaces are easily removed. I cannot personally see that it would be reasonable to try to remove any of them after assembly. Perhaps I missed a trick.

Some things do work well, but have weird quirks. The supports for the wheel rods and fuse braces are nicely designed and work well, but the instructions indicate they should be mounted from the top of the wing. This would support them quite nicely from the top (because of the flanges that extend beyond the holes) but normally landing stresses will push the tubes _up_ from the bottom, which might pop them out.

The placement of some components begs for tape support. In particular, the outer hinges for the elevator leave very little foam to the edge of the stabilizer, and mine broke off quite easily. With a little tape, they were back in business. The tab for the tail wheel is another weak point, but not so easily solved. Oh, and my tail wheel barely rolls, even after trying to lube it. Make a decent skid, though.

I'm not yet done with assembly after nearly a week, and consider it a more difficult build than, say, a shockie. Some of that is doubtless due to unfamiliarity, but knowing what I know now, I'd still assume it would take longer to build a second one than most other foamies. That may just be me.

I have no idea at this point (of course) whether the flying characteristics will justify the effort. Questions about that, and power system/servos, will have to wait a bit. These comments are only meant to address the build process, with which I am almost done. I thought, however, it was best to get some of these comments "on the air" quickly. I did read this review before buying, and I have had quite a different experience from the writer. Wish I got that kit instead!

As always, this is just one kit and one builder. Hopefully some of the comments will be useful in deciding to buy, and getting a good build if you do.

Dave North
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