Brief:
This is a plastic model conversion (PMC) of the Heller 1/130 X-15, using MicroMaxx motors. I got the kit on-line from Model Expo. Model Expo provided email confirmations of the purchase and of shipment, and their service was prompt.

Modifications:
The instructions provided with this kit consisted of step-by-step diagrams. No text description is provided. In general, this was sufficient, but this presentation omitted some details, such as the slight downward cant of the rear wings. The kit consists of 35 pieces, 10 of which weren't required due to the PMC.

The LOC ¼" launch lug is heavier than a standard MMX tube and is a skosh larger. However, it works fine for those of us who haven't gotten around to buying 'real' 6mm tubes. However, with some minor trimming of flashing and other bumps inside the fuselage, this tube fits nicely. There is a recess, just inside of the tail end of the main body, which accommodates the tube well. I measured the distance from this recess to the point just ahead of the side fairings, and cut my tube to fit. Contrary to other guidance, I used this tube as a guide to cut the nose section off the main body with a razor saw. I glued the tube inside the body with black rubberized CA, and the body halves together with liquid plastic cement. I added the back nozzle cap, and then installed a section of a spent MMX casing to serve as a motor block. The Kevlar® twine was tied around the block before its installation.

I assembled the plastic nose cone using plastic cement. I then filled the cone most of the way with lead shot, epoxied in a small piece of the ¼" lug and the remaining part of the spent MMX motor. I inserted the end of the Kevlar® twine, filled the MMX motor section with more shot, and capped it all with epoxy. This works nicely as a shoulder, but requires wrap of masking tape to fit snugly. The CG is 2 1/8" from the nose cone tip (minus the needle nose). It was suggested that the CG should be about 2.032 from the tip (from a known stable conversion of this kit), but no more #9 shot will fit, so I'll try it as is. Oh, and I decided to leave the needle off until I have assessed the rocket's stability. I wouldn't want to poke anyone, plus it will most likely break anyway.

The large front fin comes in one piece and must be cut to accommodate the tube. One end of this fin conveniently has a notch that almost fit the tube, so I used this as a guide and sanded to fit. I used the black rubberized CA on the root end of these through the wall fins, and plastic cement on the outside. The remaining fins were assembled per the instructions using plastic cement. I did add some really small epoxy fillets on the back fins using epoxy left over from the nose cone. The launch lug is my standard BiC ink tube

Construction:
Parts:

• One Heller 1/130 X-15
• LOC ¼" launch lug ~3" long
• LOC ¼" launch lug ~ 3/16" long
• One spent MMX casing
• Section of the ink tube from a BiC pen
• Kevlar® twine
• Teflon plumber's tape
• #9 lead shot

The whole thing was painted black using brush on enamel. The needle will be white with red stripes someday. The kit comes with a raft of decals, which went on nicely. However, I made one BONEHEAD mistake. I had put the clear top from my clear enamel on a can of white primer. In my haste due to the cold outside temperatures, I didn't pay attention and laid a thin coat of white on the model before I caught myself. I quickly removed the paint as best I could with some paint thinner. Surprisingly, I only damaged one decal. After a day of drying, I laid on some clear enamel. Since I couldn't get all the paint off of the fin joints, I retouched it. The finish looks bad up close, but there is not much that I can do without ruining the decals.

Flight:
I used Teflon plumber's tape for the wadding and the streamer (12"). I flew the model on a MMX-II motor and used a bit of masking tape to retain the motor. I used my Pratt GO-BOX and a stock igniter that was removed from its plastic shell. The wind was perfectly calm. The flight was a little wobbly and the X-15 flew to about 25 feet. Since the CP-CG is marginal, I wouldn't fly this rocket except in the lightest of winds.

Summary:
This small X-15 was only my second PMC and was straightforward. The rocket looks great and seems to fly fine. My only recommendation to others building this kit is to use lighter tubing. With the heavier tubing, most of which is behind the desired CG, it is difficult to balance the model properly. Mine is probably just barely stable with the whole nose filled with lead shot. Another option might be to have the rocket separate further back, thus allowing more room for nose weight.