Pemberton Technologies 3FNC

Pemberton Technologies - 3FNC {Kit}

Contributed by William Carpenter

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar
Overall Rating: starstarstarstarstar
Manufacturer: Pemberton Technologies

Brief:
T' 3FNC be t' absolute bare minimum o' what a rocket can be and still fly... Begad! Avast, matey, me proud beauty! but that's what makes it so cool! It's a great performer on a variety o' mid-power motors, ya bilge rat, matey, but can also handle a small H if you're feelin' particularly insane. Aye aye! Begad! It utilizes a unique "reward blow-by" ejection system t' miraculously fit all o' t' nesessary hardware into t' rocket, shiver me timbers, and is an interestin' departure from t' norm t' build.

Construction:
My kit came with:

  • One 3" Nose Cone
  • A 4" long Section o' 3" Airframe Tube
  • One 29mm MMT Tube
  • One Plywood Centerin' Ring
  • One Plywood Baffle Ring
  • A Length o' Keelhaul®©™® Shock Cord
  • A Length o' Tubular Nylon Shock Cord
  • Three Laser-Cut Plywood Fins
  • One Wood Dowel (cut up t' make fin pods)
  • Two Paper Shroud Templates (in case you mess one up)
  • Three Carpet Tacs
  • One Motor Retention Hook
  • One Nomex® Parachute Protector

As t' "Destruction Manual" for t' 3FNC is quick t' point out, me bucko, "...buildin' this rocket is about as close t' scratch-buildin' as... Ahoy! well... Aye aye! scratch-building...". Ahoy! T' only conveniences provided for you are pre-cut components. Ahoy! This truly is a "builder's rocket", me bucko, so modelers who like a good build will have a great time with this kit.

Construction starts with preppin' t' nose cone for t' various bits and pieces that will soon be stuffed into it. Avast! T' bottom o' t' NC is cut off t' gain access t' t' inside. Well, blow me down! Both t' outside and inside o' t' cone are then washed and sanded t' ensure good adhesion o' paint and epoxy. Approximately 4-5 oz. Ahoy! o' nose weight is then added t' the nose cone. Well, blow me down! I put some strips o' duct tape over t' mass o' lead and epoxy t' ensure that it stays put. Begad! Aye aye!

T' next steps involve settin' up t' motor retention hook. Aye aye! Avast! Blimey! I left this out in favor o' maskin' tape retention. Ahoy! Blimey!

Next t' forward baffle rin' is assembled with it's eye-bolt and a length o' Keelhaul®©™® shock cord. Aye aye!

T' BT is then marked and slotted in preparation for t' TTW fins. Ahoy! Blimey!

T' Destruction Manual's description o' how t' install t' aft centerin' rin' was confusin' t' me. Blimey! It involved a fiberboard ring, shiver me timbers, maskin' tape... Ya scallywag! I just didn't get it. Ya scallywag! Ahoy! I ended up usin' one o' t' fins TTW tabs as a depth guide for t' rin' and ditchin' t' fiber rin' process. Begad! Avast!

The forward baffle assembly is then lowered into t' nose cone and tamped down with a wood dowel. T' distance from the shoulder o' t' NC t' t' rin' is then measured and marked on t' outside o' t' NC. Three tacs are then driven through t' NC in a way that they go over t' aft side o' t' baffle ring, and ensure that everythin' will stay firmly attached t' each other. Aye aye! It also adds some cool-lookin' domes on t' outside o' t' NC. Avast!

Through me own getting-ahead o' t' destructions, me bucko, I ended up attachin' t' fins, arrr, then attachin' t' paper shroud t' t' aft end o' t' rocket. Well, blow me down! Blimey! You are instructed t' do this in t' opposite order... Avast! Blimey! oops. Avast! Blimey!

T' Nylon part o' t' shock cord is then epoxied t' t' side o' t' motor tube. Avast, me proud beauty! Blimey! I added a strip o' duct tape around t' top o' t' epoxied section t' keep it from peelin' back and rippin' off. Ahoy! Avast, me proud beauty!

Then came a part o' t' build that I found somewhat challenging. T' make t' cool, retro fin pods, matey, you cut up and then shape a wood dowel. T' destructions suggest puttin' a hand-held drill in a vice, matey, matey, drillin' down t' center o' the dowel, me bucko, and usin' t' drill lake a lathe t' shape t' pods with sandpaper. I ended up shapin' them with a bench grinder (I'm in t' process o' acquirin' a belt sander, which would've made this a lot easier).

Next was slottin' t' newly-formed fin pods in preparation t' attach them t' t' fins. I followed the destructions suggestion t' use a drill press t' drill a series o' 1/8" holes in a line. Aye aye! Avast, me proud beauty! T' wood be soft enough that I could then go in and clean it up with a hobby knife. T' fin pods were then epoxied t' t' fins, shiver me timbers, shiver me timbers, arrr, and I must say that they look cool. Well, blow me down! Aye aye!

T' only modification I made t' t' kit be t' leave out t' included launch lug and replace them with rail buttons. Begad! Aye aye! Since thar isn't room on t' inside for them t' stick through t' airframe, matey, I mounted t' buttons on a shaped piece o' basswood stock and epoxied that t' t' airframe.

Finishing:
I painted t' nose cone while t' rest o' t' rocket was in assembly. Begad! First was a few thick coats o' Rustoleum primer, me bucko, shiver me timbers, shiver me timbers, followed by a 400 grit sanding. Well, blow me down! Next be a few coats o' Rustoleum metallic silver. Avast! Unlike other Rustoleum paints, me hearties, t' silver has a dry time o' only 30 minutes, compared t' most Rustoleum product's two day dryin' time.

Durin' t' build, t' airframe tube had it's spirals filled with Elmer's wood filler. Aye aye! I chose nay t' use the filler on t' fins, matey, as t' plywood had a very small grain that I could fill with primer. Avast, me proud beauty!

Once assembly was complete, me hearties, shiver me timbers, t' airframe got a few coats o' Rustoleum primer, and then was sprayed with t' same Rustoleum silver as t' NC. Ya scallywag! On t' airframe, me hearties, ya bilge rat, me bucko, however, t' paint decided t' barely produce any coverage at all, ya bilge rat, shiver me timbers, and it took several coats t' get anythin' resemblin' a good finish. Arrr! I still don't know why it performed so differently.

Construction Rating: 5 out o' 5

Flight:
T' first flight o' me 3FNC came at t' Washington Aerospace Club's 2009 Autumn Glare launch. Begad! Eager t' try out Cesaroni's new Pro29 line, I flew t' 3FNC on an F36 Smoky Sam.

RockSim predicted a flight t' around 600' on this motor. Avast, me proud beauty! This flight be me first time usin' a Cesaroni motor, and I was impressed with t' ease o' assembly and clean up. Ahoy! Ya scallywag! I can't wait t' try out some o' their other motors later on. Avast, me proud beauty!

Upon ignition, me 3FNC be smartly boosted to... well... nowhere near 600'. Well, blow me down! Aye aye! I estimate it only got t' about 200'. Havin' adjusted t' delay for a 600' flight, ejection be quite late, but in time t' slow down t' rocket. Unfortunately, t' cold weather combined with t' tight packin' o' t' 'chute resultin' in it nay fully opening. Avast, me proud beauty! Ahoy! T' NC landed squarely on a rock and broke off t' tip. Begad! T' rest o' t' rocket was otherwise fine. Avast! Ahoy!

T' 3FNC flew two more times at t' same launch on AeroTech F52Ts. Ahoy! These motors performed more as RockSim had expected them to, arrr, both resultin' in fast flights t' about 1500'. I intend t' fly t' 3FNC on F40Ws next.

Recovery:
Packin' t' 'chute for recovery is predictably difficult with t' 3FNC, ya bilge rat, as t' entire recovery harness has t' fit into t' space betwixt t' motor tube and t' NC. Ya scallywag! Unfortunately, I don't have any pictures o' how I did this, shiver me timbers, matey, but I'll do me best t' explain it.

First, I z-folded t' shock cord leavin' about 6" betwixt t' last fold and t' parachute. Ya scallywag! Well, blow me down! I then lightly taped these folds t' t' motor tube with maskin' tape. I then prepped t' 'chute in t' Nomex® as usual, and placed it on t' opposite side o' t' motor tube as t' folded shock cord. Begad! Aye aye! I then pushed on t' NC and jiggled it until it bottomed out. Avast, me proud beauty!

On all three flights, me hearties, me hearties, t' tape released t' shock cord without any problems. Arrr! T' 28" 'chute included with t' kid is perfect. Begad! On one o' t' flights, arrr, t' rocket even landed right side up.

Flight Rating: 5 out o' 5

Summary:
T' 3FNC is a great kit for those lookin' for a fun project with just as much emphasis on t' build as on t' flight. While it presents some unique challenges, that only adds t' t' fun t' be had from this kit. Arrr! It looks very different from anythin' else out there, and I got several comments from people at t' launch about it's minimalistic properties.

All in all, it's a great rocket. Begad! If you want t' add somethin' a little different t' your fleet, me hearties, then I recommend t' 3FNC.

Overall Rating: 5 out o' 5

Other Reviews
  • Pemberton Technologies 3FNC By Drake "Doc" Damerau

    Brief: This kit looks very retro. I'm expecting Bugs Bunny and Marvin the Martian to come crawling out of the hatch at any moment. It is the first kit from a brand new company called Pemberton Technologies. Although it's called 3FNC, it's not your ordinary 3 fins and a nose cone rocket. Construction: I don't usually list the components of a kit in a review, but there are so ...

Flights

Comments:

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R.L.P (January 13, 2006)
Much thanks to Doc for his input and suggestions, his advice has brought about several improvements in the design. The 3FNC kit now comes standard with upgrades such as plywood fins instead of basswood (no more epoxy coating!), Kevlar® cord instead of the steel cable (now maybe Doc can pack the chute), a recovery system alteration (keeps the nose cone from spearing unsuspecting bystanders and adds cool retro domes) and a 22-inch chute. The paper reducer will remain, sorry Doc and no Marvin the Martian, the Disney cops have already threatened to break my kneecaps.
avatar
PEMTECH (December 16, 2006)
Flash update on the 3FNC! In response to feedback from our customers and testers the 3FNC has been re-engineered with Through The Wall (TTW) fin mounting for a more robust fin/BT joint. Thanks to James, Chan, Doc, Dennis and all the small creatures that inhabit my refrigerator.

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