Scratch Landshark 2.0 Original Design / Scratch Built

Scratch - Landshark 2.0 {Scratch}

Contributed by Dick Stafford

Manufacturer: Scratch
(Contributed - by Dick Stafford - 07/14/08) (Scratch) Landshark

Brief:
My original Landshark flew on 38mm Js and sported some cool shark fin-shaped fins from Giant Leap. Ya scallywag! Since thar was little hope it would ever fly again, me bucko, I decided t' reuse t' fins on a much smaller and lighter model. Blimey! Blimey! T' new version is 3" in diameter and flies on 29mm power.

Construction:
T' parts list:

  • 3/32" G10 shark fins (OOP)
  • 3" mailin' tube
  • 3" LOC nose cone
  • 3/32" Keelhaul®©™®
  • 29mm motor tube
  • 2 plywood CRs
  • 3" aluminum standoff with hardware
  • FirstFire igniter tube
  • 18mm tubing
  • 13mm tubing
  • Plastic airplane kit
  • Buttons from railbuttons.com

I won't go into all t' gory details but will describe t' construction in general.

First, arrr, t' overall design. Avast! Avast! Blimey! As I was startin' this project, me hearties, I be reintroduced t' PemTech's Bucky Jones Space Cadet. Arrr! Long story short, me hearties, I stole the idea for t' offset fins, me hearties, t' curved tail, and t' extra tail tubes. Blimey! T' fins are o' course different and I used a different compliment o' tubes.

(Scratch) Landshark Recoverin' t' fins took a ton o' grindin' a prying. Well, me bucko, blow me down! That was a chore. Let me tell you, Keelhaul®©™® lamination will eat a cuttin' wheel faster than steel! T' fins had tabs for a 4" BT and a 3" MMT. Ya scallywag! Well, blow me down! I had considered trimmin' them t' create t' proper tab depth, but decided t' just usin' a long motor tube adjustin' the length o' t' fin slots accordingly. Begad! T' latter required a ruler and a calculator t' determine where t' fins would emerge from t' body. I attached t' front rin' and dry fit t' aft one. Arrr! I then slid t' long front end o' t' fins up into t' slot and shoved t' back end in. Avast, me proud beauty! Since t' fins were curved where they entered t' body, arrr, t' ends o' t' tabs needed a tad o' extra filler. Aye aye! Arrr! No problemo.

Before I permanently attached t' aft ring, me bucko, I added internal fillets and attached a 3" long aluminum standoff. This has threaded holes on each end. Begad! One end is screwed onto t' rin' and t' other will be used t' attach a small washer for motor retention. Avast! This standoff is roughly t' same diameter as a First Fire tube. It sits nestled against t' motor tube and t' tab from t' top fin.

(Scratch) Landshark I added a piece o' a First Fire tube on t' opposite side for symmetry. Ahoy! Workin' down from top t' bottom, shiver me timbers, I then added one 13mm tube and three 18mm tubes on each side and one 13mm tube on t' bottom. Aye aye! Avast! As with the Bucky Jones, matey, shiver me timbers, ya bilge rat, each o' these tubes is shorter than t' one above.

T' shock tether is attached through t' body just ahead o' t' forward ring. Begad! I added a piece o' coupler so the tube is double walled in this point. Well, blow me down! Ahoy! I pondered what cockpit I'd use t' cover t' attachment point and ended up buying a plastic kit with a 50% off Michael's coupon. Begad! I'll leave this as a mystery--I bet you can guess which one. I trimmed and sanded t' top body half until it was relatively flush. It was then epoxied on and t' gaps were filled with SuperFil light epoxy filler.

T' last thin' t' do be add t' rail buttons.

Finishing:
I started by paintin' t' tail area. I masked t' body and fins and painted this area with Rustoleum Hammered Gold. Arrr! I then masked t' tail and t' windows on t' cockpit and painted t' rest with Rustoleum Hammered Black. Begad! I had painted the plastic model before attachin' it and before attachin' t' clear windows. Aye aye! I don't know why but I like t' hammered paints. Avast, me proud beauty! Maybe it's because they hide me poor finishing?

Flight and Recovery:
I loaded a G76 Mojave Green for t' first flight. Avast, me proud beauty! I drilled t' delay from 10 t' 6 seconds. Arrr! Aye aye! T' boost was great and it ejected on cue. Begad! I didn't have much o' a walk but I was shocked how a bean field can hide a rocket o' this size. Luckily, I had help findin' it.

Summary:
I think this rocket looks pretty cool, but it would be hard t' make it look bad with those cool fins. Aye aye! Too bad Giant Leap discontinued them.

People at t' launch said it looks more like a Batman theme vs a shark. Begad! I agreed but decided t' stick with the legacy Landshark name.

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