Bob Violett models BobCat XL

Model Airplane News, Sep 2002 by Tiano, Frank

You know, there are times when I'd rather refer to an article on a particular product as a "report" than as a "review." One thing's for sure: a review should not be just a reprint of the product's instruction manual; I think we have all seen that too many times. With that in mind, I'd like to tell you about my experiences with the Bob Violett Models (BVM) BobCat XL-a totally different type of model airplane kit. I use the word "experiences," plural, because I have been instrumental In building two of them at the time of this writing!

The BobCat XL is truly a state-of-the-art model jet that incorporates the latest in material selection and construction procedures. It has many composite parts but features a built-up wing and stabilizer. When a modeler who has never built a wing comprised of ribs, spars, gussets and sheeting finishes these flying surfaces, there is no kit that he won't be able to tackle. And that is part of BVM's concept with this kit: for the modeler to learn, be successful and be proud of his accomplishment.

WHAT'S IN THE BOX?

The parts for each procedure are in separate, sealed and labeled plastic bags, so when you are building the stabilizer, you don't have to worry about losing some wing or fuselage parts in the process; you simply locate the stabilizer bag and work from it. All of the wooden parts are separately bagged as well, and the first thing you'll notice is that almost all the parts-- excluding wing leading edges and spars-- have been expertly laser cut. The hardware bags are probably the most complete that I have seen to date. All that you need to complete this kit is the BobCat's landing-- gear system and an engine, fuel tanks, radio and an assortment of adhesives and tools. Lying flat on the very bottom of the box is a set of incredibly clear plans and a 55-page instruction manual. Of course, all manuals are important, but this one is unique in explaining techniques, tools, adhesives and procedures. For example, one page lists all of the abbreviations used throughout the manual and even suggests a specific particle mask to use while sanding. It tells you exactly why, when and where to use specific adhesives, how to prepare fiberglass parts for glue, and where to apply a barrier so that the internal structure is protected from jet fuel and other solvents. The manual calls specifically for Zap CA, Zap-AGap, Sheet Zap, Flex Zap and Slow Zap. It also recommends the use of BVM's own Aero Poxy, which is one of the strongest two-part adhesives on the planet. It also features photographs of tools that will undoubtedly make your building life a whole lot easier and more enjoyable. Many, many diagrams and photographs help the modeler through most construction sequences.

WING AND STAMMER CONSTRUCTION

Ninety-six photos and half a dozen diagrams in the manual are dedicated to the wing construction section. The BobCat wing is constructed upside-down over the plan and in three sections. Eventually, the center section will be permanently fastened to the fuselage, and the two outboard sections will be joined to the center section with a set of common wing tubes and a bolt on each side. The manual suggests that you buy a 24-inch steel ruler and a 24x48-inch Armstrong no. 1450 ceiling tile to use as a building board and to help keep the wing structure absolutely true. The manual also suggests that a modeler with any built-up-construction experience should expect to invest 15 hours or so in building the wings and stab.

The spars and ribs are laid over the plan, and the rib tabs are temporarily glued directly to the building board, through specific slots cut out of the plan at indicated areas. This keeps the wing structure immobile during construction. The wing has a specific area to harbor the fuel tanks, so it is a good idea to have the tanks ready during the wing-building process. That's right; the fuel tanks are in the wings, just like many real jets'! There is little chance of your having to remove the tanks, but just to cover the unforeseeable, BVM provides cool hatches in the bottom wing skin to allow you to easily service or replace the tanks. And speaking of wing skins, not only are they prejoined, but they are also printed with lines and diagrams indicating where they should be glued and what gets cut away later on. For example, the servo hatches are clearly defined on the wing skin in black ink so that when you cut them away, you're looking directly at the servo opening. The landing-gear blocks are a perfect fit and require a ribbon of Aero Poxy around their joints to ensure that they remain rigid during any rough landings. By the way, the BobCat uses its very own landing gear.

There are 16 photos of stabilizer construction, three more showing hinging and another three showing servo installation. Along with the elevator, the stab is built right on its skin, which is marked with the locations of the ribs and spars. The stab has very few parts, so it is quite easy to build and takes less than 2 hours. The elevator hinging and servo installation takes another hour or so. The construction features ribs and spars, which are then covered by sheeting. Sheeting the wing is easy with Sheet Zap; it does not run, and it takes a long time to cure, so you have plenty of time to position the wing sheeting to the spars and ribs. Both the wings and the stab are finished with lightweight fiberglass cloth and polyester or epoxy resin. Depending on your final color scheme, you may want to use Zap Z-poxy finishing resin or Sig's polyester resin. Zpoxy doesn't smell the way polyester resin does, but it shrinks for quite a while, so dark colors may need another light coat of resin so that the weave or hatch marks in the cloth don't show through after many hours in the sunlight (this isn't a problem with lighter colors).