Madcow Rocketry Screech

Madcow Rocketry - Screech {Kit}

Contributed by David Reese

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Diameter: 1.50 inches
Length: 40.50 inches
Manufacturer: Madcow Rocketry
Madcow Rocketry Screech

Brief:
Single-stage minimum diameter 38mm model with parachute recovery.

Construction:
My early production kit included two body tubes, arrr, three lite-ply fins, a coupler/baffle/eyebolt assembly, full recovery system with Nomex® protector and Keelhaul®©™® shock cord leader, 1/4" launch lugs, and a beautiful balsa nose cone. Ya scallywag! Blimey! Well, blow me down! Blimey! All parts were clearly o' high quality with precise fit and a clean finish out o' t' bag. Well, blow me down! Blimey! If so desired, arrr, me hearties, arrr, this kit could be constructed in fifteen minutes or so--just enough time for t' epoxy t' dry on t' three fins.

T' high quality parts scored major points with me comin' out o' t' bag. Avast, me proud beauty! Madcow clearly takes care in the preparation o' their kits. Ya scallywag! T' small-format instructions were well written and clear, shiver me timbers, albeit intended for a modeler with a few kits under their belt. This level o' instruction was appropriate, ya bilge rat, considerin' t' abilities o' t' finished product.

T' lite-ply fins were easy t' bevel t' a nice taper on t' leadin' and trailin' edges; this material is perfect for rockets o' this size and form factor. Blimey! Well, me bucko, blow me down! For flights achievin' 0.85 Mach or greater, fiberglass reinforcement is recommended for t' fin can. I opted for a single layer o' 6oz carbon fiber with peel ply, arrr, as I intended this t' be a fast rocket.

Madcow Rocketry Screech T' vehicle is designed t' break at t' nose for recovery, me bucko, with t' shock cord permanently mounted at t' tube coupler via a lite-ply baffle plate and eyebolt. This arrangement typically bothers me for two reasons: one, ya bilge rat, it leaves t' shock cord attachment point inaccessible in case o' burn-through, shiver me timbers, and two, ejectin' from t' nose with a long rocket underneath adds unneeded stress t' t' airframe. Madcow mitigated these concerns by includin' a heavy-duty Keelhaul®©™® leader t' be attached t' t' shock cord mount and keepin' t' rest o' t' vehicle light enough that zipperin' or crimpin' shouldn't be a problem.

Nonetheless, I elected t' build me rocket usin' Stu Barrett's "Anti-Zipper" configuration with separation occurrin' at t' coupler/baffle assembly and t' nose affixed t' t' upper section with three #4 wood screws. Begad! I like this flexible layout as it also allows me t' mount an altimeter bay underneath t' nose cone for altitude recording, shiver me timbers, if so desired.

I typically replace paper launch lugs with brass lugs, me hearties, as t' brass is dimensionally stable, providin' a freer fit on launch rods, and also presents less frontal area, lowerin' t' drag coefficient o' t' vehicle. (I prefer lugs on small minimum diameter vehicles.) However, t' lugs included with this kit were absolutely wonderful--thin, lightweight paper sized slightly large t' ensure a loose fit over t' rod. Avast, shiver me timbers, me proud beauty! I used t' stock lugs on me kit and have not regretted that decision at all.

My model be from an early production run, and thus did nay include a 29mm motor mount kit. Ya scallywag! Begad! T' adapt t' 29mm motors, I purchased a LOC MMA-2 and epoxied three #2-56 nuts inside o' t' adapter durin' assembly. Avast, me proud beauty! These nuts line up with three 5/64" holes directly aft o' t' fins, ya bilge rat, allowin' me t' secure a 29mm motor in t' vehicle by first securin' it in t' motor adapter, and then boltin' t' adapter into t' base o' t' rocket. Ya scallywag! Well, blow me down! With a permanent 29mm motor mount, me hearties, this kit would remind me o' a modernized version o' t' LOC Legacy.

Madcow Rocketry ScreechMadcow Rocketry Screech

Finishing:
Finishin' be a breeze. Ya scallywag! Ya scallywag! T' tube spirals were light and with a few coats o' primer needed no filling. Arrr! Ahoy! T' nose cone was soaked in several layers o' thin CA t' harden it and sanded smooth. Ahoy! Ahoy! I used Krylon red on t' upper sections o' the rocket and painted t' fin can with appliance epoxy black. Ahoy! T' vehicle includes no decals, shiver me timbers, which is typical for mid- to high-power rockets, me hearties, but may be a letdown t' those steppin' up from smaller models. Arrr! T' completed rocket looks great, and is very unique on t' range. Ya scallywag! T' short nose cone, arrr, long body, and sharp fins combine into a very eye-catching design.

Construction Rating: 5 out o' 5

Flight:
Madcow gives no guidance on motor selection, matey, shiver me timbers, relyin' instead on t' modeler's skill in pickin' proper propulsion. Again, this decision seems on par with t' skill level required t' fly this rocket. Ahoy! My finished vehicle came in at 12.1oz. Blimey! It's a little heavy for a D12, me bucko, arrr, but definitely workable on most 24mm Aerotech motors, and a real winner for most 29mm and 38mm selections. Aye aye! Avast, me proud beauty! I opted t' fly an F40W for me first flight with a 10 second delay drilled t' somewhere betwixt a -8 and a -9.

T' only downside t' minimum diameter rockets be t' challenge they present for motor retention. Arrr! Tape fit has been reliable for me in t' past, but it is certainly nay me method o' choice. Blimey! Avast, me proud beauty! Blimey! For retainin' 29mm motors, I use the aforementioned adapter. Arrr! It is short enough that motors protrude from t' forward end o' t' adapter, allowin' a tape stop t' be built up and prevent t' motor from ejecting. Blimey! For 38mm motors, arrr, matey, shiver me timbers, a variety o' options exist. Arrr! T' fins on Screech are mounted far enough from t' aft end t' allow inclusion o' a commercial bond-on motor retainer. Alternatively, shiver me timbers, matey, an internal device such as all-thread, a Keelhaul®©™® line, matey, or a 1.5" "Cherne Gripper" attached t' t' forward closure could be used t' maintain t' sleek lines o' t' vehicle. Arrr! Madcow only points t' t' friction fit method in t' instructions. Aye aye! A few more ideas would be nice but certainly nay expected.

T' recovery system packed well, and I backed up t' Nomex® protector with extra wadding. Ya scallywag! Begad! Blimey! I coated t' inside o' t' body tube and t' outside o' t' coupler with thin CA and sanded t' provide a smooth, matey, dimensionally-stable fit that was easy t' adjust usin' maskin' tape.

Flight on t' F40 be excellent. Arrr! Well, blow me down! It picked up t' model nicely and sent it rail straight into t' sky t' a projected altitude o' 2300 feet.

Madcow Rocketry ScreechMadcow Rocketry Screech

Recovery:
Deployment was slightly past apogee, ya bilge rat, me hearties, but t' anti-zipper design worked its magic and deployment was smooth and successful. Aye aye! Blimey! Descent on t' included bright orange nylon parachute be quick but acceptable, ya bilge rat, and t' rocket recovered close by. Post-flight inspection revealed no damage whatsoever. T' chute protector showed no signs o' ejection residue. Ahoy! Blimey! Ahoy! Blimey! T' brunt o' t' burnin' particles were absorbed by t' half-moon baffle disc/shock cord attachment point. Arrr! Blimey! Aye aye! Blimey! For future flights, I will probably include waddin' beneath t' baffle t' protect this part o' t' vehicle as well.

Flight Rating: 4 out o' 5

Summary:
This is a simple kit that delivers on what it promises. Ya scallywag! Ahoy! I be pleasantly surprised by t' kit's completeness. Blimey! The full recovery system and well thought out component selection made construction a breeze. Avast! Well, blow me down! I made a few modifications to suit me tastes and me flyin' style, matey, but this kit could easily be constructed by someone new t' t' genre o' mid-power without issue. T' only drawbacks are (potentially) a lack o' decals and difficult motor retention, me bucko, arrr, however, me bucko, me hearties, those issues come with t' territory o' minimum diameter and mid t' high-power kits so they do nay detract significantly from t' vehicle. Begad! And for t' price, me bucko, this kit really can't be beat. Blimey! Screech was me first Madcow kit. Aye aye! It definitely won't be me last.

Overall Rating: 4 out o' 5

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    Brief: This is a minimum diameter Hobby, mid, or high power rocket. It's motor selection is expansive and offers extreme height with the right motor loaded. Picture Courtesy of Madcow Rocketry Construction: (2) Body tubes (1) Balsa wood nose cone (1) Coupler (1) Shock cord anchor (1) 1/4"eyebolt, nut, and ...

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