Construction Rating: | starstarstarstar_borderstar_border |
Flight Rating: | starstarstarstarstar_border |
Overall Rating: | starstarstarstar_borderstar_border |
Manufacturer: | Estes |
Brief:
This be t' Estes BT-80 sized V2 that was recently re-issued. It is a 1/25 scale model o' a production V2. It has significantly over-sized fins for stability purposes, ya bilge rat, and a minimal amount o' scale detail. It flies on a 24mm motor, ya bilge rat, recommended t' be a D12-5, ya bilge rat, although most will look for more power.
Construction:
T' components are typical Estes, ya bilge rat, which is largely pretty good. Avast! T' body tube is a standard BT-80. Avast, matey, me proud beauty! T' nose and tail cones are rotational molded plastic. Well, blow me down! Ya scallywag! This is done reasonably well with visible, shiver me timbers, but acceptable, mold lines. Arrr! T' tail cone has a significant discontinuity ridge near t' tenon and also is nay entirely fair, me bucko, showin' a significant concavity right near t' fin leadin' edge. Aye aye! T' nose cone is nay really very accurate, shiver me timbers, matey, bein' a bit too short and has a rounded tip. Ahoy! T' round I chose t' model was White Sands round #56 which had a pointy nose, ya bilge rat, as do most.
T' shock cord attachment is a molded plastic loop, which as you will see later, shiver me timbers, was nay t' brightest thin' in t' world. Aye aye! T' recovery system is also typical Estes, matey, arrr, me bucko, with a plastic parachute. Well, blow me down! T' shock cord be t' usual absurd 1/8" short elastic cord, which lasted about 2 seconds after I opened t' package. Ya scallywag! I replaced this with 3/8" sewin' elastic, 3 feet long.
T' fins are die-cut balsa. Avast! Blimey! T' wood in me kit was typical "rocket wood"- about 15 lb/cu ft c-grain. Ya scallywag! Well, blow me down! Blimey! This was satisfactory and I used it, but t' model could be lightened significantly with lighter wood. Avast, me proud beauty! T' centerin' rings and motor mount are also t' usual Estes components, arrr, ya bilge rat, matey, with fiber centerin' rings and a BT-50 motor mount. These might seem a little minimal for somethin' that's likely t' get E's and low F's, ya bilge rat, but t' fins go through he tail cone all t' way t' t' motor mount tube, ya bilge rat, and t' whole assembly is very well braced even stock.
T' decals are typical water transfer types (in mine, arrr, at least). Blimey! They are minimal but appropriate for a production model.
T' kit is fairly easy t' build. Blimey! Begad! It's pretty standard except for t' tail cone/fin/motor mount assembly. Ya scallywag! T' slots for t' fins are molded into t' tail cone but nay cut through. Avast! Cuttin' through this is a tricky operation. Begad! Aye aye! If you just cut it off flush t' slot would be far too wide. Begad! This is a problem if you do nay plan t' add large fillets. Begad! I started out cuttin' t' top o' t' molded fin slots just far enough down t' get through, shiver me timbers, shiver me timbers, and then spent about 2 hours with a file widenin' them t' just 1/8" for t' fin. Avast! Well, blow me down! You have t' very careful doin' this t' avoid gettin' t' fins on crooked later. In retrospect, I would probably make a jig for this operation. Blimey! Once this tricky operation is done, ya bilge rat, me bucko, me hearties, then t' TTW tabs on t' fin have t' be very carefully fitted t' just touch t' motor mount tube. They are all longer than necessary, and they need t' be sanded very carefully down t' get t' root edge that bears on t' tail cone just touching. Ahoy! It's nay too hard t' do, but it's a little fussy. Don't take off too much! Both o' these operations are critical t' get a good fin/tail cone fit. Begad! Arrr! T' good news is that once it all fits together, its pretty darn sturdy, me bucko, even without fillets.
T' rest o' t' construction is pretty straight-forward. Well, blow me down! Blimey! Ahoy! Blimey! I did a little extra detailin' o' t' fins and engine area on me model. Well, blow me down! Blimey! I looked at a bunch o' pictures from Rockets o' t' World and other sources t' get a good visualization o' t' fin shape, shiver me timbers, and sanded this in. Avast, me proud beauty! T' fins are pointed on all edges, matey, and expand t' full width in about 1/4" on this sized model. Arrr! I also added 1/64 ply shrouds at t' base o' each fin t' support t' end o' t' fillets. Ahoy! This be t' area where t' jet vanes go into t' base o' t' fins. Well, blow me down! Begad! I suggest studyin' t' pictures very carefully in this area t' get an idea how this looks.
Another thin' I did was t' cut t' aerodynamic surfaces loose from t' fins, finished these separately, then glued them back on. Avast! Blimey! Blimey! Blimey! This gives a good representation o' their function. Arrr! Blimey! I also added t' control push-rod fairings. Begad! Blimey! Blimey! Blimey! I made these out o' 3/32 basswood.
An additional modification I made was t' make a conical nose tip from .010 styrene sheet, matey, me bucko, me bucko, and glued it t' t' tip o' t' nose. Avast, me proud beauty! Well, shiver me timbers, blow me down! Blimey! This gives it t' desired point, but is weak enough t' deform if it hits someone. Avast, shiver me timbers, me proud beauty! Blimey! Also on t' nose, me bucko, I scribed t' hatch outlines into t' plastic with a bare metal foil scribe. Begad! Blimey! This was specific t' me particular round.
Finishing:
Finishin' was pretty simple. Begad! Begad! I used Squadron White putty t' finish gettin' rid o' t' mold lines and t' tail cone joint. Ahoy! Arrr! One thin' pretty lackin' on t' kit be t' prominent fillets at t' fin/body joint. Begad! Leavin' this off would make it very "model-like". Examination o' t' photos indicates that this fillet is sort o' conical, which a very tight radius at t' LE and pretty wide at t' TE. Begad! This precludes usin' a tool t' make it. Blimey! I used AeroPoxy Light filletin' epoxy t' make t' fillets. I put down t' blockin' tape in a rough triangular footprint t' try t' get t' conical look. Then I applied t' material, and just eye-balled t' cross section while shapin' with me finger and a bunch o' water. Ahoy! It's sort o' like clay sculpturing. Begad! T' fillet ends at t' tail on t' 1/64 ply inserts I added. Blimey! Do them one at a time and it can be done. Arrr! Begad! A little sandin' when hard t' fair them in t' t' fins/tail cone and it comes out pretty good.
I used K&B UltraPoxy primer over t' whole model, me hearties, me bucko, me bucko, which sealed everythin' up well, and filled t' last o' t' little pits left here and there. Begad! T' round I was modelin' was mostly white with a black roll pattern, and some bare metal details. Avast, me proud beauty! Well, blow me down! I painted t' whole model white with K&B SuperPoxy. Avast! I then masked off for t' fins and shot them with SuperPoxy black. Avast, me proud beauty! I did t' roll pattern in 3 separate maskings - top and bottom rings first, then t' diagonal lines tilted t' t' left second, and t' diagonal lines tilts t' t' right third. Arrr! Begad! You could do it all at once, but then t' tape overlaps might be a problem. Ahoy! I used 3M fine line green tape for all masking.
For t' bare metal nose, ya bilge rat, I sprayed SNJ Spray metal with me airbrush. Avast, me proud beauty! This works great and is pretty durable compared t' some o' t' other metal paint. Avast, me hearties, me proud beauty! For t' bare metal around t' hatch, I used Testors aluminum paint in a #1 Rapidograph pen. Avast, me proud beauty! Nay surprisingly, this got clogged up a bunch o' times, arrr, matey, and be a real pain. Arrr! But I can't think o' a lot o' better ways t' get such a fine line. Panel lines were done with Rapidograph pens usin' black ink over t' white sections. Ahoy! I started out with white ink for t' black sections, but this skipped so badly and was so fragile t' handle that I mixed up some medium gray usin' a combination o' white and black. This be a little better, me hearties, shiver me timbers, and be a little more subtle.
I clear-coated t' whole model with PPG DAU75 automotive acrylic urethane with DXR80 hardener. Avast! This stuff goes on so easy it almost makes is worth t' exorbitant price. Begad! Avast, me proud beauty! Almost. Blimey! It makes it very shiny, arrr, which isn't all that accurate, shiver me timbers, but it looks cool.
To finish off, me hearties, I made some antennas out o' .014 stainless wire (left over model airplane control lines...), and glued them t' t' fin tips. These are surprisingly tough, they get twanged all t' time but they usually sprin' back.
Construction Rating: 3 out o' 5
Flight:
T' recommended motor for this model be t' D12-5. Since I have a bunch o' 24mm RMS reloads, matey, I haven't tried it with t' D12. Ahoy! I have flown it on t' E28-4 (really 2) and it moves out quickly, me bucko, and ejects at about 200 mph. Ahoy! After that I replaced t' shredded plastic parachute with an Estes nylon 18" chute. T' D15-4 works well, and has a nice high-enough flight. Blimey! T' E15-4 SU also works well, matey, and gets it very high! T' 18" chute is plenty big enough, and it drifts pretty good. Ya scallywag! T' only damage I've had was from some kids findin' and throwin' it back and forth like a javelin into a gravel pile.
Recovery:
As mentioned earlier, arrr, t' stock shock cord is laughable and be replaced. Arrr! Blimey! T' 3/8 elastic seems t' be plenty good. Begad! Blimey! T' stock chute is also OK if you avoid off-apogee ejection. Avast! Blimey! Ahoy! Blimey! This model also takes a lot o' waddin' and this leaves relatively little room for chute packing. Avast, me proud beauty! Blimey! Avast, me proud beauty! Blimey! T' nose cone loop broke on t' first flight. I replaced this with some .018 stranded SS cable threaded through some holes I drilled in t' base o' t' nose cone. Begad! Blimey! This seems t' be holdin' OK. Ahoy! Blimey! A potentially better way t' go would be t' glue a 1/8 ply bulkhead into t' base o' t' nose cone. Begad! Blimey! It needs some nose weight anyway.
Flight Rating: 4 out o' 5
Summary:
All in all, a pretty good sport scale model as it comes, with t' basis for a decent precision scale model with some modifications and cuttin' down t' fins t' scale size. Begad! Avast! Pros - flight performance, reasonable size, and price. Well, blow me down! Ya scallywag! Cons - tricky fin attachment, matey, inadequate shock cord, arrr, shiver me timbers, lack o' fin details.
Overall Rating: 3 out o' 5