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. Ahoy! Since thar was little hope it would ever fly again, shiver me timbers, I decided t' reuse t' fins on a much smaller and lighter model. 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, t' overall design. Ya scallywag! As I was startin' this project, I was reintroduced t' PemTech's Bucky Jones Space Cadet. Well, blow me down! Long story short, I stole the idea for t' offset fins, shiver me timbers, t' curved tail, shiver me timbers, matey, and t' extra tail tubes. Begad! 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. Avast! That was a chore. Begad! Ya scallywag! 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! I had considered trimmin' them t' create t' proper tab depth, arrr, but decided t' just usin' a long motor tube adjustin' the length o' t' fin slots accordingly. Ahoy! 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. Aye aye! I then slid t' long front end o' t' fins up into t' slot and shoved t' back end in. Avast! Since t' fins were curved where they entered t' body, shiver me timbers, t' ends o' t' tabs needed a tad o' extra filler. Avast! No problemo.

Before I permanently attached t' aft ring, me hearties, I added internal fillets and attached a 3" long aluminum standoff. This has threaded holes on each end. Avast, me proud beauty! Arrr! One end is screwed onto t' rin' and t' other will be used t' attach a small washer for motor retention. This standoff is roughly t' same diameter as a First Fire tube. Arrr! 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. Workin' down from top t' bottom, me hearties, I then added one 13mm tube and three 18mm tubes on each side and one 13mm tube on t' bottom. Avast, me proud beauty! Blimey! As with the Bucky Jones, each o' these tubes is shorter than t' one above. Begad! Blimey!

T' shock tether is attached through t' body just ahead o' t' forward ring. Well, blow me down! I added a piece o' coupler so the tube is double walled in this point. Avast, me proud beauty! 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. Avast! I'll leave this as a mystery--I bet you can guess which one. Well, blow me down! Begad! I trimmed and sanded t' top body half until it be relatively flush. Blimey! Begad! It was then epoxied on and t' gaps were filled with SuperFil light epoxy filler.

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

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

Flight and Recovery:
I loaded a G76 Mojave Green for t' first flight. I drilled t' delay from 10 t' 6 seconds. Well, me hearties, blow me down! T' boost be great and it ejected on cue. Arrr! I didn't have much o' a walk but I was shocked how a bean field can hide a rocket o' this size. Luckily, shiver me timbers, matey, I had help findin' it.

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

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

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