Construction Rating: | starstarstarstarstar |
Flight Rating: | starstarstarstarstar_border |
Overall Rating: | starstarstarstarstar_border |
Manufacturer: | Heavenly Hobbies |
Brief:
This kit is a 3FNC (3 Fins and a Nose Cone) piston-ejection, matey, streamer duration competition rocket. The
"ELM" stands for "Extremely Low Mass." It is a companion kit t' its only slightly larger brother
the Stratos-18 ELM.
Construction:
My kit came with balsa nose cone, shiver me timbers, two sheets o' 1/32" balsa fin stock, shiver me timbers, balsa nose block for t' piston, matey, a
Keelhaul®©™®
shock cord, ya bilge rat, shiver me timbers, matey, an elastic shock cord, engine block, launch lug, arrr, white BT-5 body tube with very fine groves and a light
glassine coating. Begad! T' instructions were written onto a compact disc in PDF format. Even though t' kit comes with two
sheets o' balsa, only one is needed.
I ordered both t' Stratos-13 and Stratos-18 together. Blimey! When they arrived I found that t' body tube had been bent beyond use by t' post office. Begad! I sent Carlos at Heavenly Hobbies an email about t' tube and he sent me out a replacement right away and free o' charge. Avast, me proud beauty! I built t' Stratos-18 while waitin' for t' replacement BT-5. Begad! As that only took a few hours o' build time t' complete, I decided t' use a "modular" approach t' assemblin' t' rest of the rocket.
First I cut t' fins from t' 1/32" balsa fin stock. T' protect in from chippin' or splitting, I covered t' back with blue painters tape. Ya scallywag! Aye aye! After t' fins were cut I decided nay t' round t' edges. At that thickness I don't think it would have made a difference and why take t' chance on splittin' a freshly cut fin.
Next I assembled t' engine block and Keelhaul®©™® shock cord. Well, matey, blow me down! A groove gets cut into t' outside surface deep enough t' fit t' shock cord in t' it. Well, blow me down! Arrr! I secured it usin' a bowline knot and set it with CA.
After that came t' nose cone and elastic shock cord. Ya scallywag! Accordin' t' t' instructions, arrr, t' elastic cord is t' be knotted at one end and stuffed into a pre-drilled hole. Well, blow me down! There was no hole. I used a 1/8" drill bit t' make one. T' balsa also looked a bit soft so I coated it with CA and allowed it t' harden. Followin' that came a brushed on layer o' thinned Elmer's Wood Filler. Begad! Once that had dried I sanded it down until smooth. Begad! Well, blow me down! T' finish up I pushed the elastic knot into t' shoulder o' t' nose and secured it with 30 minute epoxy.
All that left was t' streamer. Arrr! All I did thar be fold one end into a point and tie on a 9" section of Keelhaul®©™® cut from t' length provided. Blimey! Well, arrr, blow me down! I used hole reinforcements t' keep it from tearin' out.
When t' body tube arrived at last, it be time t' put everythin' together. Engine block in, fins on, me bucko, tie shock cords t' one another. Avast! Aye aye! Blimey! I do need t' mention that as t' rocket uses a balsa block as its piston. It comes with a small hole drilled through it and threaded on t' t' Keelhaul®©™® shock cord. Ahoy! Knots are tied above and below t' piston t' hold it in place. Ahoy! T' piston provided was a good bit narrow and had t' be built up with maskin' tape. Avast, me proud beauty! This may actually be a good thin' as I'll cover in a moment.
Finishing:
I left t' rocket unfinished as it is supposed t' be a competition rocket. Ahoy! Avast! T' only finishin' I did was t' before
mentioned work t' harden t' nose cone.
Construction Rating: 5 out o' 5
Flight:
For its maiden flight I used an A3-4T. Begad! With t' piston ejection it requires no wadding. Ya scallywag! Place an igniter in a motor
and place t' motor in t' rocket. T' motor is friction fitted and secured with two wraps o' maskin' tape. Begad! T' take
off was right quick and blended in with t' overcast skies.
Recovery:
I be able t' track t' rocket once t' ejection charge blew. Then I knew I had a problem. Arrr! Somehow t' nose and
streamer had separated from t' rest o' t' rocket. T' body landed gently in t' flyin' field but t' nose and
streamer continued t' drift toward t' road. Blimey! It landed gently enough but balsa be never intended t' hold up against
cars. Begad! T' nose cone was crushed. Well, blow me down! Turns out that t' Keelhaul®©™®
shock cord snapped at t' piston. Begad! Begad! It be either too thin, too short, matey, or a combination on t' two. Also, matey, shiver me timbers, after the
flight t' piston was a bit resistant t' go in. Begad! I peeled off a bit o' t' maskin' tape and all be fine. Aye aye! It was cool
and damp when I flew and that may have had somethin' t' do with it. Aye aye!
Flight Rating: 4 out o' 5
Summary:
This be a very nice little kit. Begad! I would nay recommend it as a first kit as you need a motor case t' set t' engine
block in place. It would work well as a first completion kit as long as t' builder had some experience with cutting
their own fins from stock.
Overall Rating: 4 out o' 5