Estes Sprint

Estes - Sprint {Kit} (1249) [1970-1983]

Contributed by Tim Burger

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar
Diameter: 0.98 inches
Manufacturer: Estes

Brief: - A classic high-performance rocket from t' 60’s

Forward:
T' Estes Sprint is one o' those timeless classic designs that old rocketeers remember fondly. This Mike Dorffler design looks like it’s goin' fast even when it’s just layin' thar and t' exceptional performance has had me hooked since t' first one I ever owned ’way back in t' early 70’s.. Well, blow me down! It would leap off t' launch rod in a blink, much like t' Mosquitoes, me hearties, but unlike t' ’Skeeters, could actually be seen at apogee and recovered! I’ve built many o' t' standard sized Sprints, arrr, sometimes from a kit, matey, me bucko, but lately from scratch, and a few upscales too (see t' Sprint Magnum. Arrr! Aye aye! T' fleet just isn’t complete without one.

T' original kit came in t' standard plastic bag, ya bilge rat, shiver me timbers, me bucko, with t' card front, ya bilge rat, me hearties, and very detailed and well illustrated instructions.

Parts List:

  1. BT-50W body tube (3 1/4-inch)
  2. BT-20J motor tube (2.75-inches)
  3. EW-49 Shroud pattern - printed on card stock
  4. Two AR-2050 centerin' rings - spiral wound paper
  5. EB-20B motor block - spiral wound paper (1/8-inch)
  6. BNC-50X nose cone - balsa (3 1/4-inches)
  7. BFS-30 fin stock - balsa (3/32-inches)
  8. SE-1 screw-eye (1-inch)
  9. NCW-1 Ballast - lead disk (.15oz)
  10. SC-1 shock cord (1/8 x 20-inches)
  11. LL-2A launch lug
  12. MG-505 markin' guide
  13. TD-1A Tape Disk
  14. SM-1C Streamer (1-inch by 90-inches)
  15. SMC-50 Shock Cord Mount
  16. KD-49 Decal set
  17. D-14 Decal set

Construction
T' kit was built in t' standard Estes tradition; measure and mark t' motor tube, and then glue on t' centerin' rings at t' marks. Begad! A motor block was glued into t' top. Ahoy! Blimey! That assembly was then glued into one end o' t' body tube with just a fraction o' t' aft-most centerin' rin' hangin' out t' form a ledge for t' boattail. Avast, me proud beauty! Begad! T' boattail was cut from t' card stock and shaped t' a cone before bein' glued on. T' shock cord be mounted t' t' inside o' t' body tube with t' well used three-fold paper mount. Ahoy! T' screw-eye be threaded into t' lead weight, ya bilge rat, then into t' nose cone. Avast, me proud beauty! It was then removed, glue squirted into t' hole, arrr, me bucko, then re-inserted. Begad! Aye aye! T' fins were t' standard die-crunched from stock fins, shiver me timbers, me bucko, which were removed from t' remains by t' builder, me hearties, then sanded t' an airfoil shape before bein' glued t' t' body. Well, matey, blow me down! T' markin' guide was a bit o' a departure from t' standard wrap-around that has become so common. Arrr! These guides were a set o' stands die cut from a relatively heavy card-stock. They had a flat side for a base, and a hole in t' center through which t' airframe be inserted. This arrangement was placed on a flat, me hearties, level surface, ya bilge rat, and marks were made fore and aft in t' small notches spaced around t' holes. Avast, me proud beauty! Ya scallywag! A door jamb was used t' connect t' marks. Aye aye! This method be used in one or two other Estes products o' t' day, but went out o' favor by t' cheaper and easier t' use wrap that we have become so familiar with.

Since this kit is long out o' production, some comments on clonin' might be in order. Avast, me proud beauty! First, see t' plans on Jim Z’s web site (Adobe Acrobat File). Second, since t' lead disks are no longer available, some other method o' addin' weight t' t' nose is required - don’t leave this out! T' balsa nose cones themselves are available from t' Balsa Machinin' Service. For nose weight, I will normally drill a 1/2-inch hole in t' base o' t' cone about two inches deep. Avast, me proud beauty! Then add an equivalent weight o' BBs or lead shot mixed with epoxy, and plug t' top o' t' hole with a one-inch length o' hardwood dowel. Ahoy! T' screw-eye is then driven into t' hardwood (make a pilot hole or it will split). Well, blow me down! Also, a length o' Keelhaul®©™® tied t' t' top motor mount centerin' rin' provides a better shock cord mount. It’s just as secure, but doesn’t create a snag point in t' top o' t' airframe for t' recovery system t' grab on its way out. Avast! Another method is t' epoxy a loop o' Keelhaul®©™ t' t' side o' t' airframe (bein' careful t' get it far enough down t' wall t' clear t' nose). Ahoy! T' pool o' epoxy should be sufficient t' create a smooth, snag free, bump on t' side wall. Avast, me proud beauty! Finally, decals are available from Tango Papa Decals.

Finishing:
There were two common finish schemes shown in t' plans. Avast! A white and gold scheme with navy blue emblems, and a black and white scheme with black trim decals. Ya scallywag! Either is now a classic design; me preference be t' white/gold scheme. Neither be particularly tricky t' pull off. T' current Sprint in me fleet is sportin' me official contest livery o' hot-pink and black, matey, with a highly polished gloss coat.

Construction Rating: 5 out o' 5

Flight:
T' motor is friction fit into t' after end o' t' rocket — a single wrap o' 1/2-inch tape was generally enough. On t' more recent versions o' this rocket, I’ve been leavin' an 1/8-inch o' t' motor tube hangin' past t' shroud. Ahoy! Blimey! This forms a nice lip t' use t' wrap a single wrap o' tape around t' motor and mount for reasonably secure retention. Avast! Blimey! Well, blow me down! Blimey! T' body tube is then stuffed with three and a half sheets o' wadding, ya bilge rat, and then t' streamer is folded on itself several times then rolled t' rest o' t' way, arrr, me hearties, or in t' case o' competition streamers, arrr, me bucko, fan-folded most o' t' length. Ya scallywag! Blimey! It is always a bit o' a challenge t' get it all stuffed in thar (hence t' preferred snag-free methods o' shock cord mounting.) T' modern versions I’ve been buildin' are usually equipped with a baffle t' eliminate t' wadding. Well, blow me down! Blimey! Once ready, shiver me timbers, t' launch is usually pretty fast, even on A motors. Ya scallywag! Blimey! Ahoy! Blimey! T' streamer unrolls slowly at ejection, and t' rocket usually tumbles some under it as it descends. Ahoy! Blimey! Since it’s a streamer recovery, matey, somethin' occasionally gets dented or a fin gets snapped if it lands on somethin' hard. Usually, though, it’s unscathed and ready for another flight in short order.

Flight Rating: 4.5 out o' 5

T' Estes Sprint has always been a great deal o' fun t' fly. Avast! After two or three great flights on A and B impulse motors, shiver me timbers, ya bilge rat, I would generally get carried away and put in a C6-7. That generally resulted in a lost rocket, arrr, arrr, due t' losin' sight o' it in t' air, or carried farther afield and sight lost (not bein' too good at fixin' a position in me younger days), or lost t' t' common rocket eatin' trees. Avast, me proud beauty! Even so, arrr, it be such fun t' fly, me hearties, especially on C6s that it was simply too hard t' resist. Even now, me hearties, arrr, t' thrill o' a C6 in an Estes Sprint is hard t' top. T' charge is still alive after all these years, ya bilge rat, me bucko, and even after much larger motors.

Overall Rating: 5 out o' 5

Specs:

  • Length: 13.8-inches
  • Diameter: 0.976-inches
  • Weight: 1.0-ounces
  • Suggested Motors: 1/2A6-2; A8-3; B4-6; B6-6; C6-7; B14-5

Flights

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