jpolenek

cloaking device

I contacted Frank Pullano Jr., the guy that made the video. It's called "Reflections of Earth" and it comes from the Disney album called "Epcot Tapestry of Dreams". Joe Polenek

Here it is: http://uk.youtube.com/watch?v=K-TXl-pNQZg There may be more than one song there. If so, the one I'm inquiring about is in the second half of the video and plays to the end. Joe Polenek

Can somebody identify the music used in Glasss Overcast's 2003-2004 Highlight Reel? (It must be well known since ABC News used parts of it in their coverage of the inauguration today.) Joe Polenek

I'm trying to 5S my shop to make a little more space. Should I keep some of the left-over blocks of polystyrene foam from the wings/canard or just haul them all to the dump? Some of the pieces are too irregular to be useful, but there are plenty of small to medium-size blocks that look too nice to just throw out. (The words of a pack rat. ) I started the Cozy project on chapters 10/19/20 first, so the rest of the plane has yet to be done. Are there places throughout the project where this extra foam would come in handy? Joe Polenek

My plans were purchased circa 1997 and IIRC the revised layup schedule for the wing and canard were already included in the plans. They were prefaced with a letter from Viking stating that althought ther had been no in-flight structural failures, they felt the need to re-engineer those layups because of the growing trend of builders making the Dragonflys heavier than the plane was intended to be. Although the letter doesn't mention it, part of the reason may have been because a few people broke their canards on hard and/or bouncy landings. This applies to the MK I with the main gear at the ends of the canard, so if you have a MK II or III, the revised layup schedule may not be as important. Joe Polenek

According to Viking's [revised] spar lay-up schedule, the canard's upper and lower spar caps should have 9 plies and 6 plies respectively, at their thickest points (near the root). They taper down to 2 and 2 near the tips. Joe Polenek

Can anybody recommend an on-line source for quality antenna wiring parts, especially less common BNC connectors like the UG-260? Jim Weir's article talks about these, but they don't seem to be available on RST's website. Joe Polenek

Nice beak. Joe Polenek

Based on the write-up in RST's antenna kit, a garden-variety copper foil dipole with 6.3" ears should work. (l=2575/F.) Joe Polenek

If the tape you used is thicker, then the number of plies needed to get the same strength may be different. You should try to find out the details of your tape, and those of the "correct" tape. If you assume that the strength of a lay-up at any given point is related to the amount of glass, then you could compare your 6-ply layup with somebody else's 11-ply layup in terms of the total cross-sectional area of glass. You might find that your lay-up is very comparable. You would need to determine the number and size of filaments of each type of tape. Also, you would want to verify things like the surface finish of your tape, type of glass (S-glass versus E-glass) and hence tensile strength, etc. There's probably more to it than that (I'm no composites expert), so if you take such a theoretical approach, a perusal of Marshall's Composite Basics would be a good start. Joe Polenek

The attached photo shows a flaw I just discovered in my UND fiberglass cloth. It appears to be caused by a gap in the cross fibers - they look like they are a bit more closely spaced on one side of the gap. The primary fibers that give the UND its strength appear to be fine. I can't think of any reason not to use it, but I thought I'd post this in case somebody has a different opinion.

I thought that the idea behind keeping blue foam away from fuel tanks was that in the event of a leak, it would still be better to have [fuel-resistant] fuel-soaked foam that's providing support to the fiberglass, than to have a void. Joe Polenek

Somebody did this to a Dragonfly. IIRC, it was more of a "gullwing canopy" so that the longerons didn't have to be moved down too much. Probably a tight squeeze getting in & out. You should be able to find some photos on-line through the Dragonfly group. If you're talking about full gullwing doors like a Velocity, that's a MAJOR fuselage re-design that few (if anyone) would recommend. Joe Polenek

A builder on the Cozy Mailing List suggested using the cedar strip canoe method. I looked that up on YouTube and it's probably the way to go. http://uk.youtube.com/watch?v=WAwj8_5SuHk http://uk.youtube.com/watch?v=KcmMfkm-euU Joe Polenek

Could I get some advice on what materials to use to make a very precise, smooth mould? The idea is to make the shape, drape several layers of fiberglass over it for strength and further smoothing of the surface, and then get Aircraft Windshield Co. to stretch-mould Plexiglas over it to make a canopy. I was thinking of using MDF, but because of the shape I need, some kind of filler would have to be used in various places between the different pieces of MDF. The "sand-ability" if this filler would have to be the same as the MDF in order to make a smooth shape, without bumps where the dissimilar materials meet. Would plaster of paris work? Are there different materials and/or techniques that can be used? Does anybody know what Cory Bird did when he made the mould for his Symmetry canopy? Joe Polenek

Actually, it looks more like the front end of the tandem Su-30. I suppose you can get away with that when you've got a couple of AL-31 turbofans helping you along:) , but I would still expect some aerodynamic penalty for tilting the entire fuselage this way, as the Intruder does. But I'm no aerodynamacist. It will be interesting to see how the performance compares to the LongEZ. In any case, the Intruder is a beautifully styled plane! Joe Polenek

I'm curious about the aerodynamics of a fuselage that flies with its long axis at an apparent negative angle of incidence (i.e. w.r.t. the relative airflow). Would this cause more canard loading to keep the nose up, increased drag due to the frontal area, or both? Joe Polenek

Could I get some advice on finishing the canard lift tabs? Here are a few specific questions I have: 1) Since the canard lift tabs from CG Products have a nice bead blasted and alodined surface, is it recommended to paint them or leave them as they are? (If painting, I would do this before installation and mask the areas that will be bonded inside the canard). If so... 2) Should I spray it with zinc chromate primer first? 3) Can I expect a partial 8-year-old can of zinc chromate primer to still be any good once I give it a good shake? 4) Is a Tremclad-type outdoor paint or an automotive touch-up paint from a spray can good enough for this application or is there a specialty product that should be used? Thanks. Joe Polenek

I started this way by building a wood mould, but couldn’t get packing tape to wrap around the corners (compound curves) without rippling. Electrical tape probably would have worked nicely because it is stretchy. Just as well, though, because there are a couple of advantages to using a foam core for the insert, which I didn't realize at the time: 1) It is easier to fabricate the plugs out of foam than wood, especially when you're making six of them at once. (The number of set-ups and overall fabrication time is reduced by processing them as a batch of six, rather than making them one-by-one.) 2) The other big advantage of a foam core is that it provides rigidity to the fiberglass when bonding it into position. I needed clamps to squeeze all the micro out of the way and get the insert to bottom out in the depression. The two layers of BID alone are pretty flimsy and would likely bend and distort when doing this. If you used a removable mould and waited to remove it after the fiberglass was bonded in place, the lack of flexibility might make the de-mould difficult. Joe Polenek

So the website wasn't really "under construction" all this time???

Here is a technique I used for my wing attach depressions. Not sure if other builders are already doing this or if I'm the first, but it made sense to do it this way, as I couldn't figure out how to avoid making a big mess of it following the plans' method. So this was my process: 1. Make a plug from Styrofoam. This way, it's very easy to get perfect radii using a router, sander, etc. 2. Prep the foam with medium-dry micro slurry to fill the cells, then do the 2-ply BID layup over the foam. Peel ply where possible. 3. Use jig and router to cut a depression at the required location in the wing that will fit the insert. 4. After cure, remove peel ply, scratch sand the insert and micro it into the depression. (Use generous amounts of micro to fill all the voids, thick enough so it doesn't run out but runny enough to enable the excess to squeeze out and allow the insert to sit at the bottom of the depression.) 5. After cure, trim the insert flush with the surrounding surface of the wing. (This is one of the many times when a Fein tool is REALLY handy.) 6. Remove foam from inside the insert and scrape the sides down to the glass. If you remembered to micro-prep the foam before glassing, and it was fairly dry micro, then it will scrape off nicely right to the glass. A 4" screw with Vice Grips for a handle works beautifully as a rasp. A bend in the screw enables it to get into the corners easily. 7. Use a small strip of coarse-grit sanding belt (e.g. 1"x4") and sand the inside of the depressions to smoothness. The method takes a little more work than the plans' way, but the final result is well worth it if this type of detail is important to you. Joe Polenek

Ok. Here it is: a couple of photos of the botched first attempt, a pictorial of the trim sequence, photo of the final product, and a write-up. Joe Polenek TailSpring.txt

If you can, do what I did when I bought plans. Take a road trip to Oshkosh (or similar event that's attended by canards, if another one is closer to where you live) and see if someone will let you sit in their Cozy. You will get the opportunity to meet a bunch of wonderful people from the canard community and see their nice planes, and the experience will inspire you for the build. Joe Polenek