The Allegro-Lite 2-meter glider I’ve just completed have taught me a number of things — some Allegro-specific, others model-building specific. I thought I’d share my thoughts here, in one place for the benefits of others.

The Allegro-Lite was a pretty advanced build for me (and I think for most folks!), so having only completed maybe a half dozen balsa kits beforehand, I still had a lot to learn. The Allegro is very exacting, and needs to be built as closely to plan as possible, so good tools and techniques (and patience) are demanded.

Read on for a listing of the tools and tips that I have amassed during my build…

Overall shop design and configuration

1. Good, flat tables are a necessity. Hollow- or solid-core doors (available at your local Home Depot for $20-$30) and some 2×4’s make excellent shop tables. I have a plane for some here: http://thelocust.org/gallery/20040830workbench

2. Plate glass is a gift from the gods. For the perfect working surface, find an old entertainment center for a decently-sized sheet of plate glass. Remember that glass is essentially a liquid-solid, and can bend and warp (slowly) so the thicker the better.

3. Wax paper and grocery bags (plastic). Wax paper is great to cover plans and resists adhesion from most adhesives. It’s fairly stiff, lays flat and is transparent. Plastic grocery bags (HDPE – high-density polyethylene) also resist adhesion by epoxy! This can be used to “pot” servos, or cover sensitive parts when “potting” a wing to a fuselage to make a perfect joint.

Cutting, sanding, etc.

1. Hard, smooth and “true” sanding blocks are a necessity, as is a good selection of different grits of sandpaper. See if you can get a sack of “balsa blocks” from your LHS — I bought a SIG sack of balsa with numerous sizes and shapes of balsa blocks and they have served me very well. I use some Titebond to adhere strips of sandpaper to the blocks. I also have a Great Planes “T-bar” sander.

2. There is nothing quite like a new blade. Either buy a lot of blades, or learn how to sharpen old ones! Whether you are cross-grain cuting a piece of balsa or cutting covering, you need a sharp blade! Otherwise, you’ll end up with a jagged, ragged. It is the first thing someone will notice when they see your model!

3. Razor saw. I used the razor saw and jig for every cut I could on my allegro-lite! Slow, soft strokes with the razor saw make excellent, smooth cuts every time. Even free-hand cuts w/o the jig were very accurate and smooth. It is my favorite tool!

4. Free-hand sanding is for the birds (most of the time). Always use a jig to keep your sanding perfectly flat, if that is what you need. Free-hand sanding a precise angle does not work, and will most likely cause a joint made with that angle to be weak, due to the preeminence of glue to fill out the gaps. Free-hand sanding works if you are sanding in a curve or the like. Otherwise, use a block and jig, or perhaps a belt/disc sander.

Measuring!

1. Straightedges/rulers. First off are some decent, heavy straightedges. Here in Louisville, we have a “Harbor Freight” tool store. Excellent source for such things. A thin, flexible straightedge is nice as well.

2. Calipers. While you are there (at Harbor Freight), pick up some 6″ digital calipers for $15 (when they are on sale). They are very precise, and appear to be the same tool that everyone else re-brands!

3. A multi-functional protractor. I got the Multipurpose Angle Finder from Harbor Freight. A fantastic tool for $4. Much better than a regular protractor.

4. A pocket gram scale! I bought a MyWeigh 200-Z pocket scale that can measure down to .01g. It can only handle up to 200g, but that is good enough for weighing those small parts and individual panels. They can be found online for ~$25.

Tape and Adhesives

1. Tape. That 3M blue masking tape is fantastic. It doesn’t rip as easily as normal masking tape, and the adhesive is superior. I use it for everything from jigging parts in place, to labeling, to holding plans or wax paper down to the glass, to masking parts when I’m using epoxy. The adhesive is strong, yet it leaves no residue and releases easily.

2. Epoxy. I used West Systems epoxy (205 hardener, 206 slow resin) from "http://cstsales.com/" target="_blank">CST for my Allegro build — and I’m NOT GOING BACK! A little expensive, but I bought a quart of resin, and it will last me some time. Very thin compared to over-the-counter five minute epoxy, so you can thicken it as much as you’d like with something like Cabosil (fumed silica). Also, while it is is great stuff — be safe!. Most people don’t realize that you can build an allergy to epoxy! Never use epoxy w/o wearing vinyl or nitrile gloves. Latex is semi-permeable! It won’t kill you to get it on your skin, but eventually you can build an allergy to it, and then you won’t be able to go near the stuff until it hardens!

3. A small, plastic pipet is excellent for applying thin CA precisely. They sell them for a dime a piece at our local model shop. Since they are plastic, you can stretch the tips on them until the inner diameter of the tip is VERY small. Perfect for accurate gluing.

4. Eat some yogurt or pudding. Yogurt and pudding cups are excellent adhesive receptacles. Epoxy will not adhere to the plastic, and since most pudding/yogurt cups are “crushable”, after the adhesive hardens, you can just “crack” the hardened adhesive out, leaving a nice, clean recepticle again.

5. Titebond is good for wood. Titebond or Titebond II — an “aliphatic resin” is superior for wood adhesion. Thin CA is great and provides “instant” bonding, but it is also brittle! These “aliphatic resin” glues actually make a bond stronger than the wood itself. It has a fairly short pot-life, so it isn’t painfully slow to set up, unlike epoxy. It also is fairly thick, so you can easily make “fillets” out of it. Thin it to increase potlife. It is especially good for d-tube sheeting. A hard landing can “crack” a CA joint, and thereby reduce the strength of the wing. No good!

6. Syringes. They sell these at my LHS as “pinpoint glue applicators” and have low-gague (wide) needles on them. They are excellent for accurately measuring epoxy, and clean up easily with alcohol. You can also use them to squirt epoxy under wing-skins on bagged wings for delamination repairs.

Jigs and weights and such

1. A bag of shot. While lead shot is expensive, it is invaluable for curing epoxy under compression on a compound surface (like sheeting). I use some heavy-weight freezer bags and masking tape for large surfaces, and little sandwich bags for smaller surfaces.

2. Mylar! Mylar is fantastic stuff — and is needed to “shim” the spar on the Allegro-Lite during building. It is flexible and adhesive-resistant. Know someone who bags wings? They should have some mylar for you. X-Ray sheets are also made of mylar. Ask your dentist or doctor. While your at it, get some hemostats and syringes, too!

I probably learned WAAAY more than this, but my brain is now emptied. Perhaps more later!

Finally having a chance to work on it, I completed the setup last week and had a chance to test it out last Thursday, and finally do my first recordings this last Sunday during our Sunday fly. The all-up weight, including batteries for the camera module is a scant 3 ounces, and the range seems to be greater than 300 meters. Considering that it actually worked, it was a blazing success! The video signal was actually better than what I thought it would be, though it could stand for dramatic improvement and I intend in the coming weeks to improve the antennas for both the receiver and transmitter modules. For a first test, it was a great success.

Check out the two in-flight videos we recorded Sunday:

2004.09.12 – Inflight Video Gallery *

The first video, "BOT" is the camera strapped to Eric's (new) Bird of Time. The second is David Gruneisen's Kyosho Stratus (a powered sailplane). Many thanks to both of the pilots, and all who provided recording equipment.

* – NOTE:
In order to view these videos, you must have the DivX video codec installed. I would HIGHLY suggest downloading and installing the K-Lite Codec Pack, as it provides not only the DivX codec, but just about every other codec you are likely to encounter on the web, and a compact version of the Window Media Player. It's a great one-stop shop for everything you'll need to view video from the Internet.

Johnny B just sent me a new photo of his new Sailaire. Only 2 years, 7 months in the making, but it's finally done! Here's what he had to say:

Whew, it's finally finished! It sucessfully flew last Sunday in high wind conditions and did pretty well during it's 8 test flights. It is definately a floater and takes a lot of field to get it to land, (ground effect) Well I guess no airplane in it's right mind wants to be on the ground right?

Also, I (Ben) just finished my recovering and restoration of a Majestic I purchased in May from a former LASS-mate. I managed to scrape a couple ounces off her frame, and hope to fly it soon. I'm pretty happy with my new covering job, and a little intimidated with it's 3-meter wingspan!

You can view larger photos of both of these by clicking on the photos above, or browsing around in our Gallery.

Check out the photo gallery!

The winds weren't spectacular, as the thermal activity was kicking up pretty well, so sometimes the Bats were floundering — I (Ben) nearly ditched mine in the field below, but Bruce's coaching helped me to send that thing sky-high in the approaching thermal. Hank didn't fair so well, unfortunately, as he did have to take the "drive of shame" a little later on. Hank, Brian and my bats all had their maiden voyages, and all survived to tell the tale. Young Sam Marks even got into the act with a buddy-box with dear-old dad. Both Ken and Bruce had their Milleniums out and Paul brought along his Icon and got their DS grooves on. Thanks to all that came out, and those that didn't — get there when you can!

Gordy sez: "This thing holds energy, heck grabs energy, like a Wizard Compact.

Lots of fun ahead guys."

Well, the Bats have been in for a while, and they are started to turn up built! Our man Bruce even had a chance to test one out on Monday at Frankfort. To quote: "WOW this baby really holds it's speed and flies like it is on rails."

click to go to the Gallery!

I'd like to get more photos of completed or in-process Bats, so if you've got 'em, email to ben [at] thelocust [dot] org!