Scratch RAAM Original Design / Scratch Built

Scratch - RAAM {Scratch}

Contributed by Carl Tulanko

Manufacturer: Scratch
(by Carl Tulanko - 12/01/01)

Rocket with ThomasBrief:
T' RAAM, me bucko, otherwise known as t' "Radical All American Missile", is a semi-scratch built 2" HPR model that is dual-sized and can fly on a range of motors from an F40W with t' short version t' a H180W on t' long version of the model. Avast, me proud beauty! It was built with left over parts from a recently demised PML AMRAAM 2, but has only t' lower fins, hence it is half an AMRAAM, otherwise known as the RAAM. Begad! These reasons are how I came about its name.

Construction:
Recently, me bucko, I lost me first PML AMRAAM 2 after many launches t' a premature nosecone ejection in mid-flight on an H128W and wound up havin' a torn Quantum body tube that was too much trouble t' repair. Arrr! I purchased a replacement AMRAAM 2 kit, ya bilge rat, which can also be reviewed on t' EMRR site, ya bilge rat, but then be left with a totally intact aft fin assembly, piston, matey, me bucko, strap, ya bilge rat, me hearties, shock cord and nosecone. The only components purchased were a PML 2" bulkhead assembly, a PML 2" coupler, a PML 36" x 2" Quantum Body Tube, matey, arrr, a pair o' 2.26" x ¼" Acme conformal launch lugs and two 1/8" quick links.

I began by cuttin' t' torn body tube from t' old AMRAAM 2, ya bilge rat, which left a lower section and fin assembly 10" long and completely built, including the still attached piston and shock strap. Begad! Begad! T' inside area be cleaned o' old, hard t' reach ejection powder and then sanded usin' 80 grit sandpaper. Avast, me proud beauty! Next, me bucko, matey, me bucko, a PML 2" coupler be cut lengthwise and slipped over t' black shock strap, then epoxied into t' lower fin body tube assembly so it be flush with the upper motor mount centerin' ring. This completed t' preparation o' t' lower, left over fin unit. Aye aye! Begad!

Short version of RAAMNext, I cut the 36" length o' new Quantum body tube into two 18" lengths. Arrr! Aye aye! One of the 18" sections o' body tube was integrated into t' lower fin section. Avast! I roughed up t' inside o' t' body tube, ya bilge rat, then pushed t' piston assembly completely through t' tube. Aye aye! T' lower part o' t' shock strap be covered with maskin' tape in case epoxy dripped on it from t' next step. Begad! 15 minute epoxy was used t' glue it over t' split coupler t' t' fin section, me bucko, and left me a completed lower half o' t' rocket. Begad! T' maskin' tape be removed from t' shock strap and I did tape up t' outside o' t' body tube seam until t' epoxy set to help center t' tubes with each other. Avast, me proud beauty! As a last step, me bucko, me bucko, t' nosecone was fit to this lower tube and a 1/8" pressure relief hole was drilled through the body tube two inches below t' base o' t' nosecone. Begad!

T' upper o' these two tubes was sanded on t' inside at one end and t' new PML bulkhead be epoxied inside this upper body tube. Avast! Well, blow me down! In t' next step, ya bilge rat, I coated t' bulkhead ply face with a layer o' epoxy t' make it powder proof and easier t' clean. Begad! T' bulkhead was pushed into t' newly completed lower section and fit well. Avast! Finally, me hearties, I installed t' original nosecone into t' top part of this upper tube, then marked and drilled a pressure relief hole into t' upper tube about two inches below t' base o' t' nosecone. Begad!

 Long version of RAAMT' lower section was stripped o' t' old AMRAAM paint usin' Acetone and Denatured Alcohol, then it was sanded with 400 grit wet/dry sandpaper and primed with Krylon and "Painter's Touch" white primers. Well, shiver me timbers, blow me down! About 6 coats o' primer were applied and final sanded with 600 grit. Ya scallywag! Blimey! It didn't take much t' prime; the lower fin section be already glassed, arrr, sanded and primed prior t' building since it was a leftover. Ya scallywag! Also, me bucko, since Quantum tubin' was used, t' new sections primed like a dream and only 600 grit sandpaper be needed t' smooth them out. Ya scallywag!

I painted t' body tube from t' blue seam forward in White Krylon Glossy. It was masked at t' blue seam so t' lower fin section was still primer only. Four coats o' white were added, and t' last coat was thicker then t' rest. Once finished, arrr, shiver me timbers, I let it dry overnight, then masked off t' stripes and used Red Krylon Glossy t' paint t' irregular stripes, which covered in two coats. Begad! The nosecone was painted next with four coats o' Krylon White Glossy. Begad! Aye aye! I then removed t' maskin' from t' lower area, me hearties, arrr, masked off t' striped upper section and painted this fin area with four coats o' Krylon Dark Blue. Avast, me proud beauty! It left the joint where t' blue and White meet seamless, which is what I was shootin' for.

T' upper section be next. Avast, me proud beauty! I masked off t' area from t' top stripes down, then began workin' on t' stars. Well, arrr, blow me down! I used Paintshop Pro t' make t' stars, me bucko, me hearties, then printed them out on paper. Begad! T' stars were cut out in paper strips, shiver me timbers, 8 at a time and placed and scotch taped down over a 1" thick strip o' maskin' tape which was laid on a cuttin' board. Avast! I used a Exacto t' cut out each star from the maskin' tape and placed them in t' appropriate positions. Avast, me proud beauty! 4 coats of Krylon Dark blue were painted over t' upper section and nosecone and left to sit overnight. Then I removed t' maskin' tape stars and viewed t' final product for finish.

Once t' model was completely painted, I fastened t' shock cord t' the piston and used a drop o' epoxy t' hold it in place. Avast, me proud beauty! Blimey! A 1/8" quick link was tied t' t' cord for quick removal o' t' parachute and another quick link was added t' t' bulkhead end. This second quick link at t' end allows me to quickly switch t' connection from t' bulkhead eyebolt t' t' nosecone, for a "shorty" LMR version o' t' rocket. I now have a dual purpose/sized model; T' shorty version flies on F-G motors and t' full version flies on the H motors. Aye aye! Blimey!

T' final touches were added t' t' rocket; t' 24" parachute was attached and t' PMR retainer was checked for fit usin' t' original mounts. Also, arrr, I marked t' spots for t' new Acme aluminum launch lugs, me bucko, then removed the paint and used 15 minute epoxy t' attach them instead o' t' supplied double-sided tape. A stainless ¼" piece o' launch rod was used to insure alignment, arrr, arrr, then t' first lug was mounted exactly betwixt t' fins and the second lug was mounted mid way up t' total length o' "shorty" version with t' lower tube and nosecone combined. Avast! Ya scallywag!

Flight:
RAAM on G64launch My rocket weighed in at around 30 oz for t' full version, matey, me bucko, but I have yet t' weigh it for t' short version. Begad! We converted it to the short version for it's first flight on a F40-7W, prepped it and placed it on t' pad. T' F40 was a very good choice as t' model lifted well; it be a very good launch, however, t' delay be too long for it's weight and didn't eject until it was nose down but t' model faired without a scratch. Ya scallywag! Aye aye! T' next flight was a real test o' stress; A G64-10W was built and loaded into t' rear of t' model and it be placed on t' pad. Blimey! When it lit, me hearties, it was an ANIMAL o' a motor for this rocket, t' best launch o' t' day with perfect deployment and landing. Avast, me proud beauty!

T' next launch be at our first Tripoli Mid-Ohio meet for 2001. Avast, me proud beauty! T' LONG version was configured, shiver me timbers, then I prepped a H128W with a medium delay and the rocket was prepped and motor be installed. Avast! Also, arrr, when loadin' t' motor case, I did NOT use all t' black powder ejection charge. Ahoy! Begad! T' piston ejection system actually requires less ejection charge and PML includes a chart for reference when loadin' t' charge. Well, blow me down!

After waitin' patiently, t' rocket was placed on t' pad and then came its turn. Well, blow me down! T' RAAM left t' pad like a shell shot out o' a cannon; fast, loud and very straight, but nay quite as fast as me A2. Begad! It was an awesome launch, with the sound and white smoke billowin' out t' tail. Ahoy!

Recovery:
T' RAAM reached apogee and had a perfect ejection; it then floated safely to the ground. Avast, me proud beauty! Estimated altitude was around 2600 feet and it be a very good flight. Blimey! Ya scallywag! Upon examination, t' rocket came out o' it without a scratch and I look forward t' many more launches with this sturdy bird. Arrr! Begad! It be late, ya bilge rat, so the RAAM was t' last launch o' t' day for us, arrr, but thar will be more t' come. Ya scallywag! Ya scallywag!

Summary:
T' RAAM turned out t' be one great flier! It is a stable rocket, somewhat over stable in its long 55" airframe with CG 4 body tubes ahead o' CP when loaded. Aye aye! T' shorty version also makes an excellent everyday flier for mid-power loads and it is a blast on a G64W. Blimey! But, arrr, convert it t' full length in seconds usin' t' quick links and you have a very stable rocket that can easily compete with t' Mirages and others out there, and compete well. In summary, me bucko, me bucko, if you loose a rocket, shiver me timbers, don't just throw away t' pieces, shiver me timbers, but rather use t' leftovers. Who knows, matey, you may just be able t' build one o' these RAAM's, a truly "Radical All American Missile"! 

comment Post a Comment