Brief:
The Semroc SLS Laser-X us an upscale of the classic Centuri Laser-X, which is also now produced as a Retro-Repro by Semroc. It is a single stage design that can accept a 29mm motor as well as 2 x 24mm or 4 x 18mm clusters utilizing interchangeable motor mounts.

Construction:
The kit consists of the following parts:

• Detailed illustrated construction manual
• Balsa nose cone
• Balsa transition
• 0.945" x 16" upper body tube
• 2.34" x 14" lower body tube
• Laser cut basswood fins
• 29mm motor mount
• Baffle system
• 24" Nylon parachute
• Kevlar®/tubular elastic shock cord
• Waterslide decals

My kit had one fin with a small split about an inch long near the trailing edge. It appeared to be a blemish in the wood and not something that happened during manufacturing. I worked a little glue into the split and with a little filler, it is now undetectable.

The instruction manual is typical of what we have come to expect from Semroc. They are well written and give a logical sequence to the build. The 2 piece fins fit together accurately and the lower fins are tabbed for through the wall construction. The tabs only extend into the body tube a short distance and are used as the locking mechanism for the interchangeable motor mounts.

The baffle is a basswood centering ring with a series of small holes in a circle with a coupler glued into the center. The 29mm mount and the 4 x 18mm mount have tubes that will direct the burning particles into the coupler, but the 2 x 24mm mount motor tubes seem to direct the ejection charge directly at the perforations so I intend to use some wadding in addition to the baffle when using that mount.

The upper part of the rocket consists of gluing the 4 small fins to the upper body tube and adding a couple of heavy washers held in place with a screw eye to the nose cone. I didn't glue the nose cone nor the transition to the upper tube until after painting to ease the finishing process.

The motor mounts were little kits with laser cut parts and went together easily. The mounts have notches in the forward ring that line up with the fin tabs and a 1/4 turn locks the mount into the main body tube. The cluster mounts have engine hooks and the 29mm relies on friction fit.

Finishing:
I gave all of the wood parts a coat of Minwax Polycrylic and before sanding and filling with Elmer's Interior Wood Filler. After sanding smooth, I gave them all a second coat of Polycrylic and it was ready for primer.

For the paint scheme, I decided to paint it to match my regular size Laser-X. It was first painted an overall base of gloss white. Gloss black was used for the nose cone, transition, and motor cooling fins. Gloss red was used for the upper fins and three of the lower fins.

The decals were applied next and were easy to work with and really dress up the model. They appeared to stick well so I didn't apply any clear coat over them but I would find out later that perhaps I shouldn't have skipped that step.

Construction Rating: 5 out of 5

Flight:
The recommended motors for the 29mm mount are E23-5, F26-6, or G35-7. For the 4 x 18: B6-4s or C6-5s. The 2 x 24mm: D12-5s or E9-6s.

I chose to use 2 D12-5s for first flight. It was supposed to be a drag race with another SLS Laser-X but when the countdown ended, only one rocket left the pad. The LCO gave it a second try and this time both motors lit for a nice flight with deployment just about at apogee. The chute got tangled on one of the fins but managed to finally fully open about 100ft from the ground.

When I retrieved the rocket, I found that the lower roll pattern decal had completely peeled off during the flight. I have since gone over the remaining decals with a coat of Future Floor Polish to seal them.

Recovery:
The 24" nylon parachute is good quality and neither it nor the shock cord showed any evidence of scorching. I was unable to make a determination about recovery speed because the chute only fully opened very close to the ground but the model suffered no damage.

Flight Rating: 5 out of 5

Summary:
This is a great model from Semroc. I like the design and it's one of those models that look real cool in the air. The interchangeable motor mount is a great idea and I'm hoping that it will be incorporated in future designs. The only thing that I would have liked would have been some kind of positive motor retention for the 29mm mount.

Overall Rating: 5 out of 5