| HPR-1 Large Rocket Constructor For Your Bigger Birds |
| HPR-1 is the big brother of the Rose Fin Jig - a longtime favorite of NAR Model rocketeers for rockets in the Model class. Designed to meet the special needs of larger, High-Power vehicles, the HPR-1 uses the same principles as the smaller fin jig which greatly simplify attaching fins and other details by just laying them in place and gluing them. The parts do not have to be awkwardly held in order to keep them properly positioned while the glue dries, or held or clamped vertically making it nearly impossible to get satisfactory fillets. Having the rocket conveniently at hand in the HPR-1 makes its construction much simpler, quicker, and more satisfying. Fin slots used on many large rockets make for very strong fin attachments, but they do not guarantee perfect fin alignment. HPR-1 readily provides accurate fin placement and alignment, with or without slots, thereby assuring optimum flights. Use with kits or scratchbuilt vehicles for super high, straight-up flights. Each fin rests on the Fin Plate with its root edge in contact with the body tube, or thru a slot, in contact with the motor tube, aligned with the center axis of the body by proper offset to allow for the fin thickness. The offset may be easily and precisely set to within a few thousandths of an inch, putting the center plane of the fin exactly in line with the center axis of the body. The lower edge of the fin plate may be adjusted to a convenient distance from the airframe. It is set at a 45 degree angle so that glue will flow to form symmetrical fillets. Fin slots are readily laid out using the edge of the fin plate as a guide. The rocket airframe is held on its motor tube. Two Mandrels are used which slide on the main Spindle to adjust for different lengths of motor tubes or adapters. 29 mm diameter mandrels are normally furnished. For larger diameter or multiple motors, adapters can be used to temporarily fit the airframe to the mandrels. Mandrels can be ordered in sizes from 24 to 54 mm. Motor sizes greater than 54 mm are best handled with adapters. The airframe is rotated with the index wheel and locks into position for three or four fin configurations, corresponding to 0, 120, and 240 degrees, and 0, 90, 180, and 270 degrees, respectively. Any other angle from 0 to 360 degrees may be set and held using the precision Angular Position Dial with the index wheel. The HPR-1 will accomodate vehicles with up to 32 inches diameter total fin span, and airframe diameters to over 8 inches. An external, Adjustable Work Holder is included for additional support of the rocket body, maintaining accuracy. Wrenches and other tools are furnished and no additional tools or parts are needed to use the HPR-1. New rocket designs are easily developed, starting with a body tube, laying out fin slots or directly attaching fins, and then completing the assembly, all on the HPR-1 fixture. Individually, hand fabricated in the United States from stainless steel, aluminum, and various woods, the rugged HPR-1 offers you convenience, time saving, and accuracy for your high power rocket constructions. Pricing HPR-1 Complete with External Work Holder, Tools, Base, Instructions: $649 USD. HPR-1 Mandrel sets quoted upon request. Contact us for more information and ordering data: HighTechRocketry@cox.net |
| HPR-1 shown with section of 4" dia Endeavor rocket |