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Fins |
Aerospace Composite Fins |
Fin Beveling |
Acme Fin Cans
The GROOVE-LOK is the latest in fin attachment technology. It epoxies over a 38mm motor tube and makes attaching fins much more efficient.
Made of high-strength extruded aluminium, it holds the fins in perfect alignment. It's a fin alignment guide built into the rocket.
Let's face it, attaching perfectly aligned fins the old fashioned way is a bear. You have to aim and drip epoxy down into an impossibly small space
while keeping the fins straight and aligned, making sure the epoxy and cloth are making contact, while keeping the epoxy drips out of the motortube.
off the airframe and away from your shoes. Fun, huh?
The GROOVE-LOK adds incredible strength to your fincan area, with very little weight gain.
It interlocks all fin cannister components, and transfers loads. MUCH STRONGER THAN A STANDARD FIN LAYUP.
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Comes in 4" and 6" Lengths
Pictured: 4" Length
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FITS 38mm Motortube
6" long (3.75 oz) $15.51 
4" long (2.5 oz) $10.34
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Handles 3 or 4 fin combinations,
both in 0.062" and 0.093" G-10 Fiberglass
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SEE OUR NEW COMPOSITE FINS BELOW!!
| Fin | "A" | "B" | "C" | Thick | Price |
| 1 | 5.5" | 5.5" | 2.6" | .062" | $7.66 |
| 1 | 5.5" | 5.5" | 2.6" | .093" | $9.80 |
| 2 | 4.0" | 2.9" | 1.0" | .062" | $9.46 |
| 2 | 4.0" | 2.9" | 1.0" | .093" | $10.52 |
| 3 | 7.6" | 3.6" | - | .062" | $7.66 |
| 3 | 7.6" | 3.6" | - | .093" | $9.80 |
| 4 | 8.7" | 4.0" | 1.9" | .062" | $7.66 |
| 4 | 8.7" | 4.0" | 1.9" | .093" | $9.80 |
| 5 | 6.5" | 5.0" | 2.6" | .062" | $7.66 |
| 5 | 6.5" | 5.0" | 2.6" | .093" | $11.93 |
| 6 | 9.6" | 9.1" | 6.6" | .062" | $10.13 |
| 6 | 9.6" | 9.1" | 6.6" | .093" | $12.26 |
| 6 | 9.6" | 9.1" | 6.6" | .125" | $15.40 |
| 7 | 11.6" | 5.9" | 3.1" | .062" | $9.54 |
| 7 | 11.6" | 5.9" | 3.1" | .093" | $13.81 |
| 8 | 7.4" | 4.8" | 3.3" | .062" | $8.48 |
| 8 | 7.4" | 4.8" | 3.3" | .093" | $12.74 |
| 9 | 7.3" | 5.9" | 4.6" | .062 | $7.66 |
| 9 | 7.3" | 5.9" | 4.6" | .093" | $11.93 |
| 10 | 6.5" | 6.5" | 3.1" | .062 | $7.66 |
| 10 | 6.5" | 6.5" | 3.1" | .093" | $11.93 |
| 11 | 5.9" | 5.6" | 2.6" | .062 | $7.66 |
| 11 | 5.9" | 5.6" | 2.6" | .093" | $11.93 |
| 12 | 8.5" | 8.5" | 4.0" | .062" | $10.47 |
| 12 | 8.5" | 8.5" | 4.0" | .093" | $13.67 |
| 12 | 8.5" | 8.5" | 4.0" | .125" | $16.94 |
| 13 | 11.5" | 7.5" | 5.8" | .062" | $10.47 |
| 13 | 11.5" | 7.5" | 5.8" | .093" | $13.67 |
| 13 | 11.5" | 7.5" | 5.8" | .125" | $16.94 |
| 14 | 11.5" | 7.5" | 4.3" | .062" | $10.47 |
| 14 | 11.5" | 7.5" | 4.3" | .093" | $13.67 |
| 14 | 11.5" | 7.5" | 4.3" | .125" | $16.94 |
| 15 | 13.8" | 5.3" | 2.8" | .093" | $13.85 |
| 15 | 13.8" | 5.3" | 2.8" | .125" | $16.73 |
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TECH NOTE:G-10 can be cut using a jig saw with a fine-tooth metal blade. Sand
edges smooth by hand or, better yet, with a bench disk sander or similar tool.
Careful, G-10 is very dense material and can destroy cutting bits / blades.
G-10 can cut you! Always wear hand and eye protection.
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click here for
Raw G-10 Sheet Stock!
THE FUTURE OF ROCKETRY HAS ARRIVED...
Aerospace Composite Fins!
Giant Leap Rocketry now offers the ultimate in fin material.
This aerospace composite material is used in advanced aircraft.
It is much stronger than wood, more rigid than G-10 (for equivelent thickness).
Lighter than wood, 1/3 the weight of G-10.
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An inner layer of NOMEX(TM) honeycomb,
sandwiched between either thin G-10
Fiberglass or Carbon Fiber!
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TECH NOTE: One of the many advantages of high strength composite fins is their low weight. Indeed, you can actually realize a double-weight savings. Here's how: suppose that by using composite fins, your entire rocket comes in at, say, 2 lbs lighter. Because removing weight at the AFT end of the rocket makes it more stable, that's an extra 2 lbs or so that you don't have to add as compensating nose weight. So you've saved as much as 4 lbs or more in this example. Not only is that a huge performance advantage, it opens up a wider range of possible motors.
| EDGING YOUR COMPOSITE FINS IS EASY! TO HIDE EXPOSED EDGE YOU HAVE SEVERAL OPTIONS:
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Edge the fin with a dowel of matching thickness. Simply epoxy dowel to fin, and apply epoxy fillet to fill seam. Miter corners as needed.
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Or...edge the fin with hardwood strips of matching thickness. Epoxy strip to edge of fin, and miter corners as needed. Then bevel wood strip to a sharp edge.
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Or...edge the fin with G-10 of matching thickness.
Similar process to hardwood strips,
but cutting/beveling G-10 involves a little more skill.
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SAME FIN SIZES AND DIMENSIONS AS G-10 FINS ABOVE
| | Fiberglass & Honeycomb | Fiberglass & Honeycomb | Fiberglass & Honeycomb | Carbon Fiber & Honeycomb |
| Thickness => | 1/8" | 1/4" | 1/2" | 3/8" |
| Fin #1 | $8.73 | $12.23 | $14.66 | $18.03 |
| Fin #2 | $8.73 | $12.23 | $14.66 | $18.03 |
| Fin #3 | $8.73 | $12.23 | $14.66 | $18.03 |
| Fin #4 | $8.73 | $12.23 | $14.66 | $18.03 |
| Fin #5 | $8.73 | $12.23 | $14.66 | $18.03 |
| Fin #6 | $11.19 | $15.67 | $15.40 | $18.94 |
| Fin #7 | $10.61 | $14.85 | $15.40 | $18.94 |
| Fin #8 | $9.54 | $13.36 | $15.40 | $18.94 |
| Fin #9 | $8.73 | $12.23 | $15.40 | $18.94 |
| Fin #10 | $8.73 | $12.23 | $15.40 | $18.94 |
| Fin #11 | $8.73 | $12.23 | $15.40 | $18.94 |
| Fin #12 | $11.53 | $16.15 | $15.87 | $19.52 |
| Fin #13 | $11.53 | $16.15 | $15.87 | $19.52 |
| Fin #14 | $11.53 | $16.15 | $15.87 | $19.52 |
| Fin #15 | $10.65 | $14.91 | $15.87 | $19.52 |
Now you can get RAW composite board so that you can cut your
own material!
1/8" thick nomex honeycomb with fiberglass sandwich.
(a good lightweight replacement for .062 G-10 fins, or
for mounting
boards)
$11.70 sq foot
1/4" thick nomex honeycomb with fiberglass sandwich
(great for scale projects)
$12.76 sq foot
3/8" thick nomex honeycomb with fiberglass sandwich
(great for scale projects)
$12.76 sq foot
1/2" thick nomex honeycomb with fiberglass sandwich
(great for lightweight bulkheads like my L3 project and for light,
strong but authentically thick scale fins).
$14.44 sq foot
NOTE ON PRICING: Raw board comes in various width. Your price
will be adjusted slightly due to different sizes of the
board. Normally, these come in 12" widths and up to 36" or
sometimes 48" long.
NOTE ON AVAILABILITY: COMPOSITE BOARD IS REALLY GETTING
POPULAR AND THE SUPPLY FLUCTUATES. THEREFORE, IT IS SUBJECT
TO AVAILABILITY.
DOWEL FOR FIN EDGING:
1/8" DOWEL ...19 CENTS PER FOOT $0.20
1/4" DOWEL....29 CENTS PER FOOT $0.31
1/2" DOWEL.... 39 CENTS PER FOOT $0.42
3/8" DOWEL (MATCHES CARBON FIBER FINS)....34 CENTS PER FOOT $0.36
Ed, I got the fins today. Looks like a perfect fit. THANKS.
Judy McShannon
ACME™ injection molded fin canisters
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Using the diagram to the left, compare the dimensions of the "A" "B" and "C"
linear measurements for picking your fins. The shaded area to the left
of the fin in the diagram is the through-the-wall fin tab.
