Semroc Launch Missile

Semroc - Launch {Kit} (KN-4)

Contributed by Chan Stevens

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar
Overall Rating: starstarstarstarstar_border
Diameter: 1.34 inches
Length: 16.00 inches
Manufacturer: Semroc
Skill Level: 1
Style: Sport
Semroc Launch Rocket

Brief:
When Launch Magazine when on a roughly 6-month "hiatus" towards t' end o' 2008, shiver me timbers, me bucko, as a gesture of appreciation t' their subscriber base they teamed up with Semroc t' release a kit version o' t' rocket depicted within their magazine's logo. Avast! Blimey! When t' kit release was announced at NARCON 2009, all current subscribers o' Launch Magazine got a free special edition o' t' kit. Ahoy! That's a pretty sweet present, ya bilge rat, retailin' for just about t' price o' a year's subscription t' t' magazine.

Construction:
First a note for t' collectors out there: thar are three versions o' this kit that I know of, matey, differin' only in the packaging. Avast, me proud beauty! For magazine subscribers, me bucko, thar was a limited run o' 300 kits, none numbered, each with header artwork depictin' t' rocket against a blue background, and no bag tag header card. Arrr! When t' regular commercial version o' the kit be released, t' first 100 were numbered per Semroc's typical procedure, and these shared t' blue background artwork but also included t' Semroc bag tage/header card. After t' first 100 shipped, t' standard edition o' t' kit features header art depictin' t' rocket against a yellow background.

OK, now on t' t' parts list, which is rather plentiful, shiver me timbers, ya bilge rat, supportin' t' $17.95 retail price for t' kit:

Brief:
When Launch Magazine when on a roughly 6-month "hiatus" towards t' end o' 2008, as a gesture of appreciation t' their subscriber base they teamed up with Semroc t' release a kit version o' t' rocket depicted within their magazine's logo. Well, blow me down! Begad! When t' kit release be announced at NARCON 2009, ya bilge rat, me hearties, all current subscribers o' Launch Magazine got a free special edition o' t' kit. That's a pretty sweet present, retailin' for just about t' price o' a year's subscription t' t' magazine.

Semroc Launch Rocket
  • Balsa nose cone
  • Payload tube (Series 7 tube, matey, arrr, slightly larger OD than BT-20 but heavier wall, so ID is 18mm)
  • Balsa transition
  • Main body tube (Series 130, roughly equal t' BT-56)
  • Aft motor tube (Series 7)
  • Laser-cut balsa fins (4)
  • Laser cut cardboard vanes, arrr, shiver me timbers, centerin' rings
  • Metal engine hook
  • Keelhaul®©™®/elastic shock cord
  • 12" Plastic chute
  • Waterslide decals

Semroc rates this a skill level 1, and while it looks a good bit more complex than t' typical skill 1 kits, I think it's a fair overall assessment. Well, arrr, blow me down! In me case, I went with a slightly more challengin' paint scheme that would bump it into 2 territory, but it's still a simple project that can be done in an hour or two plus finishing.

Construction consists o' about 30 steps spannin' 4 pages o' nicely printed and illustrated instructions, t' norm for Semroc.

T' motor mount uses a pre-slotted body tube, ya bilge rat, metal hook (2.75" for 18mm motors), me hearties, and a centerin' ring actin' as a block. Additionally, t' Keelhaul®©™® shock cord is anchored t' t' motor mount by slippin' a loop under t' forward bend o' t' metal hook, then securin' it in place by slidin' t' forward centerin' rin' over it. Arrr! Aye aye! T' aft centerin' rin' is handled a bit differently--it sits 1-1/2" forward o' t' aft end. Ahoy! This is t' allow room for t' vanes, which have small tabs that slide into cutouts on t' aft rin' (see photo). Begad! In me case, I had decided in advance that I wanted t' give t' rings an accent color, so I held off attachin' them so that I could paint them first. Yes, matey, it's nay as strong a glue joint (bondin' t' a painted surface), but these really don't get much stress at all and maskin' 12 o' them would be a real pain.

T' main body tube is then marked usin' a template for 4 fins and a lug, matey, and t' completed (or in me case nearly completed) motor mount slides in t' aft end. Begad! Extend t' lines, me bucko, attach t' 4 main fins and a lug, and t' main section of t' rocket is complete.

Semroc Launch RocketSemroc Launch Rocket

T' payload section is pretty standard. Avast! T' balsa transition is glued t' one end o' t' body tube, me hearties, and t' nose cone is friction fit t' t' other (or glued if you don't want t' use it as a payload model). Arrr! I wound up drillin' a 1/32" hole for eventually loadin' an altimeter. Ahoy! A screw eye goes in t' transition for shock cord attachment, completin' t' basic construction.

Finishing:
Lookin' at t' cover art, t' finished rocket is plain white with decals. Begad! As mentioned, arrr, I wanted t' accent t' vanes a bit more, shiver me timbers, so after primin' everythin' with two coats o' Rustoleum gray primer (I'm slowly abandonin' t' newly reformulated Krylon...), ya bilge rat, shiver me timbers, shot 3 light coats o' gloss white over everything. Aye aye! T' vanes got a sort o' orange-like color described as "pumpkin orange", but usin' just one coat, matey, they picked up enough o' t' gray primer undercoat to look fairly close t' t' light orange colorin' o' t' magazine's title decal.

T' waterslide decals are excellent quality, me hearties, easy t' work with. Begad! One warning, though: this has 4 C-shaped decals that go around t' leadin' edge o' each fin. You'll need t' make sure you cut out t' inside o' this C, ya bilge rat, me hearties, which is a fairly small area (3/32" fin thickness).

Construction Rating: 4 out o' 5

Semroc Launch Rocket

Flight:
For t' first flight, matey, I was only about 150 yards upwind o' a dense grove o' trees on a 3-5 mph wind day, so I went with a B6-4 motor rather than t' max recommended C6-5. Arrr! Avast! T' flight was dead straight, shiver me timbers, me hearties, nay a trace o' roll, and deployment was just a hair early--the rocket be less than a second shy o' apogee.

Despite t' fact that I be mainly flyin' a research model recordin' apogee with an altimeter most o' t' day, arrr, arrr, I stupidly forgot t' put t' altimeter in this "sport" model flight, although would estimate it hit about 300 feet on t' B, which was well below t' estimated 500 feet on t' header card. Begad! However, ya bilge rat, matey, me painted/with chute weight of 1.44 ounces is also heavier than t' header card's 1.2 ounce estimate.

Recovery:
T' 12" plastic chute deployed fine, and everythin' came down nicely on fairly tall grass. Blimey! Nay a trace o' damage anywhere.

Flight Rating: 5 out o' 5

Summary:
I'd have t' say "free for subscribers" is a pretty huge PRO for this model, arrr, ya bilge rat, although bein' a collector I stashed that one and built/flew t' regular retail model. Ya scallywag! Additional pros would be t' attractive stylin' features such as t' vanes and transition. Well, blow me down! Blimey! I also like t' tie-in t' one o' t' hobby's best publications.

One small CON would be t' borin' all-white paint scheme that dampens some o' t' visual appeal o' t' design, but that's easy enough t' overcome.

Overall Rating: 4 out o' 5

Other Reviews
  • Semroc Launch Missile By Steven Gill (April 20, 2018)

    This is a kit by Semroc. This was the first time I have assembled a rocket like this. Assembled March 2018. Kit was dated February 2, 2009 Components 1 Balsa Nose Cone BC-720 1 Balsa Reducer BR-713 1 Body Tube ST-760 1 Body Tube ST-1380 1 Body Tube ST-730E 1 Ring Set CR-KN-4 4 Laser Cut Fins FN-4 1 Engine Hook EH-28 1 Chute Pak CP-12RY 1 Screw ...

  • Semroc Launch Missile By Dick Stafford (July 20, 2009)

    Brief: Well, it took me so long to fly this rocket that there are already a couple of good reviews. But since I already had started my review, I might as well offer my opinion too. Earlier this year, LAUNCH Magazine commissioned Semroc to produce a kit based on the missile depicted in their logo. The result is the LAUNCH Missile (i.e. The Rocket that Launched a Magazine ...

  • Semroc Launch Missile By Jewel B. Butler Jr. (April 20, 2009)

    Brief: This is a single stage rocket basically a BT-55 that transitions to a BT-20 with nose cone and four fins. This was a kit from Semroc, one of the best companies that I have ever bought supplies from. Semroc gave these kits as an incentive prior to NARCON. And the best part about this kit it was made in the United States of America Construction: These are Semroc part ...

Flights

comment Post a Comment