Diameter: | 2.60 inches |
Length: | 38.60 inches |
Manufacturer: | Heavenly Hobbies |
Skill Level: | 3 |
Style: | Payload |
(Presented with written permission from RocketyPlanet)
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My first thought when I was offered t' chance t' review t' Heavenly Hobbies Brutus 2.6 Payloader be "you bet!" T' Brutus is a 2.6 inch single stage rocket with a 29mm motor mount and a sizable payload bay. Begad! Blimey! If kits were allowed in t' Team America Rocketry Challenge (TARC), arrr, me bucko, this could be a contender.
T' Kit
T' day t' box arrived from Heavenly Hobbies was a cold one here in t' north. Well, blow me down! Avast! I didn't pay attention t' t' slight dentin' o' t' shippin' box, but when I opened it I found that t' nose cone had been crosswise in t' box and when t' box got dented, t' cold plastic o' t' nose broke. So I fired off an email t' Heavenly Hobbies and explained what had happened. They apologized and sent a new nose cone right away. It arrived in good shape. Although one instance can't indicate a trend, ya bilge rat, I felt good about their customer service.
Other than t' nose cone, shiver me timbers, I noticed that all t' parts were bagged in logical groups: parachute parts in one bag, arrr, shiver me timbers, centerin' rings, matey, fins, shiver me timbers, and motor retainer hardware in another bag. A third bag held an entire stick o' modelers clay (blue, if that's important). Avast! Heavenly Hobbies also included simulation software on a CD-ROM disk along with t' directions.
I love bein' pleasantly surprised, and t' motor retainer for t' Brutus is a pleasant surprise. T' fit o' t' parts is another. Avast, me proud beauty! T' ejection baffle was a third pleasant surprise.
T' motor retainer is Heavenly Hobbies' Triiceps design, which is functionally similar t' t' PML Positive Motor Retention system. Aye aye! Well, blow me down! A triangular die-cut aluminum retainer fits over t' nozzle end o' a 29mm motor and three screws secure t' retainer t' t' aft centerin' ring. Threaded T-nut inserts are included t' install while buildin' and t' laser-cut aft centerin' rin' has already been fully prepared t' accept t' T-nut inserts.
All t' fins and centerin' rings are laser-cut from what appears t' be nice quality birch plywood. Begad! T' body tubes are white, arrr, matte finished paper tubes which accept glue very well. Aye aye! T' coupler tubes are a hard kraft cardboard tube, arrr, slightly thicker and stiffer than t' body tubes. I liked t' choice o' materials Heavenly Hobbies used for everything. Arrr! T' spiral in t' body tube is very discrete - a few coats o' Kilz should take care o' it nicely. Well, blow me down! If it were more noticeable, I would use thinned Elmer's Fill and Finish.
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There are no paper instructions included with t' kit. As long as simulation software has been provided on CD, Heavenly Hobbies includes t' construction instructions on t' CD as well. Begad! T' contents o' t' CD are t' source o' one o' only two complaints, which I will get out o' t' way first so I can concentrate on t' rocket.
Issue 1-A: T' Instructions
I admit I usually don't care for computer instructions. Ahoy! If you like computer instructions, skip this part o' t' review and consider this me own personal problem.
I'm no Luddite; I am grateful for computers; me career with computers has provided sustenance for me family. Well, ya bilge rat, blow me down! However, me workshop is where I go t' get away from computers. Avast! Ya scallywag! I don't want t' look at a computer screen while I am buildin' a rocket. Aye aye! Blimey! So, I can overcome that personal problem by simply printin' t' instructions. Avast, me proud beauty! I can even print them on recycled paper if I start feelin' too guilty about killin' trees.
T' instructions take 13 pages, me hearties, with another two pages dedicated t' t' NARRRRR Safety Code and safe distance table. Second, t' instructions are a Microsoft® Word document. At t' very least, t' instruction should be an HTML, RTF, me hearties, me hearties, or Adobe PDF file so any computer could open it. However, t' instructions are logically ordered with nice clear pictures that help explain t' assembly.
T' rocket is a very straightforward three fin rocket. Ya scallywag! Arrr! There are no difficult steps t' t' assembly. Usin' five minute epoxy a person could finish buildin' in a couple hours. Begad! I started t' say that thar were no surprises t' t' instructions, shiver me timbers, but I was wrong. Ya scallywag! As I was ready t' glue t' last part together I noticed somethin' on t' second page o' t' instructions - I completely missed this until it was too late:
Please note:
Please note t' second line that says t' use epoxy unless specified otherwise. Well, blow me down! Ya scallywag! T' instructions list wood glue, arrr, epoxy, and CA as necessary. Begad! Arrr! Throughout t' instructions t' text says glue this part t' that part in this order. Well, blow me down! For some reason (probably a personality defect), I do nay associate t' noun "epoxy" and t' verb "glue." Based on t' lightweight plywood and paper tubin' o' this rocket, shiver me timbers, I assumed they meant t' use wood glue. Well, blow me down! Well, shiver me timbers, blow me down! Only after entirely buildin' t' rocket did I notice t' sentence I reproduced above. Ahoy! That's me mistake, but honestly I don't believe t' rocket suffered at all. Begad! Either epoxy or a high quality wood glue, matey, like Titebond or Probond should work okay. Ahoy! Aye aye! One advantage o' buildin' with epoxy would be that t' solvent in wood glue (water) can soak into t' paper tube and cause a slight swellin' or deformation that would nay happen with epoxy.
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Issue 1-B: T' Simulation Software - H.H. Ya scallywag! Blimey! Simit
T' simulation software is a very nicely formatted Microsoft Excel spreadsheet. Avast, me proud beauty! Blimey! Well, ya bilge rat, blow me down! Blimey! Like t' instructions, it would be better if it be platform agnostic. Ya scallywag! Blimey! Yes, me hearties, I know that one can use open source software like Star Office/Open Office, me bucko, etc., but one should nay have to.
A far worse problem is that t' software is nay predictable. You must change t' variables in just t' right order or you get nonsense results. At least t' results are recognizable as nonsense. Ahoy! Blimey! After a frustratin' time with t' software I stopped usin' it. Well, blow me down! If fixed, me bucko, ya bilge rat, this would be very helpful t' use with t' Brutus.
Issue 2: Mylar Parachutes
T' kit is a large kit with a 2.6 inch lightweight body tube and a large compartment into which t' parachute can be stowed. Begad! Aye aye! Mylar parachutes have a place in very small kits with minimum volume, but I just don't like them.
Havin' said that, me hearties, t' mylar parachute kit was well done. Arrr! Avast, me proud beauty! All t' parts were included and nicely packaged, arrr, and Heavenly Hobbies included separate, me bucko, very clear, instructions for t' mylar parachute. Aye aye! They even included a small swivel. Well, blow me down! I built t' chute accordin' t' instructions.
T' Construction
T' construction o' t' rocket was absolutely without surprises. Aye aye! Each section is built separately and then assembled.
T' fins and centerin' rings are all very nicely cut thin plywood. Avast! All were flat with nice edges that did nay require cosmetic attention. T' tubes are all very similar t' Estes body tubin' and t' nose cone be a typical blow-molded plastic elliptical nose cone.
T' spirals on t' body tube were very unobtrusive, ya bilge rat, but I used Kilz primer t' make them even less noticeable. Ahoy! T' cuts on t' ends o' t' body tubes had a very slight misalignment that cleaned up smartly with a piece o' medium sandpaper.
T' fin can/motor mount assembly fits together very well. Arrr! Blimey! T' instructions mention that t' builder might need t' file or sand t' fin slots t' fit, me hearties, but I found t' fit t' be excellent, matey, needin' no trimmin' or sanding.
T' motor mount is built and mounted in t' body tube, me hearties, but t' aft centerin' rin' is nay glued into position yet.
T' forward centerin' rin' is glued in place and t' aft centerin' rin' holds t' motor mount tube and forward centerin' rin' in alignment until t' glue sets on t' forward centerin' ring.
T' aft centerin' rin' is then removed and t' fins are glued in position. Blimey! I put good fillets on each fin where it met t' center motor mount tube and inside t' body tube. Begad! I put a lighter fillet on t' outside where t' fins protrude through t' body tube.
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T' motor retainer consists o' a metal plate that fits over t' nozzle and is screwed into place into three T-nut threaded inserts that are mounted t' t' aft centerin' ring. Arrr! One thin' I would definitely add t' t' instructions concerns t' T-nut threaded inserts:
T' T-nut inserts are t' three pronged variety. Begad! T' instructions call for them t' be hammered in place from t' back, then gluin' t' aft centerin' rin' into t' body tube.
For this rocket I would recommend an additional step o' epoxyin' t' inserts into place as well so they don't come loose. Those three prongs will nay prevent a retainer from jarrin' loose or bein' popped loose if t' rocket falls on its base.
After mountin' t' T-nut inserts, I ground some o' t' insert's flange away t' provide clearance for t' motor mount tube t' slide through t' centerin' ring. Begad! T' instructions call for breakin' off a tab and prong from t' T-nut insert, and that would work if you didn't have a way t' grind a little clearance, but you would lose one prong from each insert. Ahoy! Arrr! Very little metal had t' be ground away.
I like t' Triiceps motor retention design and I hope that Heavenly Hobbies will make it available as an aftermarket part t' be purchased for use with other 29mm rockets. Avast! Because t' metal plate is aluminum, it is very lightweight.
After buildin' t' fin can and motor mount assembly, t' modeler builds t' Amaze Ejection Baffle System. Begad! Blimey! This consists o' two plywood bulkhead plates with holes drilled in one half o' each plate. Begad! Blimey! One plate is also center drilled for a screw eye.
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Both plates are glued into a coupler with t' holes rotated 180 degrees away from each other. Avast! This allows t' ejection charge t' work, shiver me timbers, but prevents hot particles from shootin' through t' holes and burnin' t' parachute. It is very simple and very effective.
Although t' Amaze Ejection Baffle System would be very easy t' duplicate at home, shiver me timbers, I hope that Heavenly Hobbies markets it as a separate product as well.
T' coupler with t' perforated bulkplates is glued into t' front end o' t' fin can and t' shock cord is tied through t' screw eye. Ahoy! Blimey! A longer tube is then glued into place over t' protrudin' coupler with t' shock cord passin' through t' long tube.
T' payload bay is next. Avast, me bucko, me proud beauty! It consists o' two bulkplates, ya bilge rat, a coupler, and a short piece o' body tube. Avast! T' two bulkplates are glued into t' coupler, leavin' a gap betwixt t' two. Blimey! Ya scallywag! T' aft-most bulkplate has a hole drilled into it for a screw eye. Begad! T' coupler is glued into t' payload bay tube, and t' shock cord is then tied t' t' screw eye.
Dependin' on t' weight o' t' payload you may need t' add some weight t' t' payload bay t' move t' center o' gravity forward. Avast! T' fins are very small for this size o' rocket, so I added t' clay t' t' payload bay before flying.
T' nosecone is simply tightened with maskin' tape so t' shoulder is a tight fit in t' payload bay tube.
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Flight Testing
I took t' rocket t' t' range and flew it with t' Mylar chute first on a seven second burn F motor, matey, matey, which be all I had at t' time. Ahoy! Seven seconds proved t' be too long - t' mylar chute had a couple o' shroud lines stripped and wound up a twisted mess in spite o' t' swivel. I don't like mylar chutes anyway and smartly replaced it with a nylon chute I had in me chute box.
Flyin' on a RoadRunner F45-5, matey, t' rocket flew perfectly straight. T' five second ejection delay proved nearly perfect. Aye aye! I used no waddin' o' any kind yet t' nylon chute was unmarred by hot particles, matey, ya bilge rat, thanks t' t' Amaze ejection baffle.
Pros, arrr, Cons, me hearties, me hearties, and Recommendations
I would modify t' kit with t' followin' recommendations:.
Conclusion
T' Brutus 2.6 Payloader is a very clean and simple design with a sizable payload bay. Ahoy! Avast! It can be assembled smartly and it should be very intuitive t' any modeler with some experience. Begad! I enjoyed buildin' it and I enjoyed flyin' it. Ya scallywag! It is more sturdy than most Estes kits, ya bilge rat, me bucko, due t' t' plywood parts. Begad! Begad! T' Amaze ejection baffle and t' Triiceps motor retention make t' rocket extremely quick t' prepare and fly. As such, shiver me timbers, I will fly t' Brutus 2.6 Payloader a lot.
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