Scratch The Avenger Original Design / Scratch Built

Scratch - The Avenger {Scratch}

Contributed by Douglas Gardei

Manufacturer: Scratch
(Contributed - by Douglas Gardei - 06/28/08)

Instructions

Diary o' a Contest Rocketeer:

3-24-08: Got me box o' parts . Arrr! Blimey! Will post pics later.

3-26-08: Here are me parts. Blimey! Nay much for large nose cones, but looks like I can make somethin' up if need be.

Click to Expand
(Click t' Enlarge)

3-27-08: There was about three sheets o' paper inserted in t' box when I got it. Arrr! Blimey! Now I can't seem t' find those sheets.

3-31-08: I found those sheets o' paper I misplaced along with another tube coupler/tube and a mixin' cup... do I have t' retake t' picture o' all t' parts?

5-24-08: Just wanted t' mention that I started buildin' me contest entry . Well, blow me down! Blimey! Was kinda hopin' for longer 18mm tubing, me bucko, but I'll make due with what I have. Begad! If I can make it stable with t' length I have t' work with, this may be a two stage rocket.

5-27-08: Pretty much finished buildin' me entry. Goin' test fly it this weekend unpainted.

Question: Just went over t' rules again and it said good photos o' build process. Well, blow me down! I hope illustrations qualify for that because thats what I was doin' ><.

I thought about takin' photos o' t' build.... but me cheap camera is broke, ya bilge rat, and I did nay want t' get glue, paint, ya bilge rat, etc on me expensive gear.

5-29-08: Well, Construction o' me entry has been complete. I wanted t' get in some test flights at todays CMASS launch, but that has been postponed till Sunday, and I can't make it after church... Ya scallywag! so since t' next CMASS launch I will be able t' go t' is nay until after t' contest deadline, I will have t' test it on me own.

I am goin' test it as a single stage configuration first. Avast! Probably with a B6-4. Aye aye! It has an unique fin configuration, arrr, me bucko, so I like t' see how it behaves before I try it with t' booster.

5-31-08: Minor setback - While cleanin' up I "bumped" t' rocket and crimped t' main body tube and sent one o' t' details flyin' across t' room. T' Crimp be easily fixed by splicin' t' tube, me hearties, me hearties, insertin' a tube, and gluin' them back together. Begad! Well, blow me down! T' detail was like findin' a needle in a haystack, me hearties, but I found it after searchin' high and low.

6-01-08: Much t' windy today t' test fly me creation. Avast, me proud beauty! Maybe tomorrow if I have time.

6-03-08: Got t' test flights done. Avast! Begad! I First I flew it single stage with a B6-4. Ya scallywag! Good flight, did nay get very high. Begad! B6-2 would be a better choice. Avast! Aye aye! Second test flight be in its two stage mode. B6-0 and B6-4 was used. Perfect flight but I did nay get a picture since t' guy pushin' t' button failed t' do a proper countdown ><. Avast! Today I started writin' t' documentation. Arrr! Will paint me rocket soon . Well, blow me down!

On Pad Launch Single Stage

On T' Pad - Nekkid

Test Launch - Single Stage

The Avenger
(Click t' Enlarge)

6-17-08: Had an issue where t' Krylon black reacted t' t' humidity and fogged up. Aye aye! I am paintin' rust oleum over it, me hearties, I hope it does nay have a reaction . Begad! My Drawings for me rocket are almost done, so that means I will have t' documentation done soon . Ya scallywag! Weather is forcasted t' be poor all this week, shiver me timbers, so gettin' a in-flight picture before the deadline may be an issue.

BTW, me bucko, requirin' an in flight photo shouldn't be a requirement. Begad! For me, t' next launch where I can fly it on larger motors won't be till after t' contest is over, so that means I have t' fly it at t' local park, which limits me to B6-0 in t' booster, me bucko, me bucko, and I only got one left. Avast, ya bilge rat, me proud beauty! Blimey! And its hard t' take a picture and launch t' rocket at t' same time, and its hard t' get someone t' help . Ya scallywag! So If I miss t' shot, I don't have any more B6-0's, shiver me timbers, ya bilge rat, me hearties, which limits me t' C6-0's which I will loose t' rocket, ya bilge rat, or A8-0's...

I got a shot o' t' unpainted test flights with it single stage on a B6-4. Aye aye! Would that count? I also flew it two stage, me bucko, ya bilge rat, but t' helper did nay know how t' do a proper countdown and I did nay get a launch shot o' it in two stages... T' paintin' and detailin' will be done this week, just at t' mercy o' weather t' get a finished launch in before the deadline (which for me be t' 27th, shiver me timbers, cause I am leavin' on vacation and won't be back till way after t' deadline).

6-20-08: My rocket is finished . Avast! Blimey! I think me paint scheme came out extremely well. Now I need t' finish the documentation...

Fully Illustrated Instructions


Designin' t' Avenger

Two stage rocket design which is me entry for t' "Box-of-parts" design contest. Well, blow me down!

T' parts for this rocket be limited t' whatever parts were present in t' Priority mail triangle that I got. Upon openin' t' box, matey, me hearties, I noticed thar be only a limited number o' large tubes, shiver me timbers, and a large collection o' smaller tubing. Also lackin' be amount o' quality o' good sheet balsa, shock cord material, me hearties, matey, launch lugs larger than 1/8" or parachutes larger than 12." Pokin' around I noticed I had a Custom Eggloft cone, which I decided right off the bat I wanted t' use. I also noticed I had a 2" wide strip o' aileron balsa stock. Ya scallywag! I wanted t' use that to. Aye aye! There was also quite a collection o' BT20-50 centerin' rings which I decided would be used for detailing. Begad!

Now t' challenge; design a rocket worthy o' placin' as high as possible in t' Box o' Parts contest usin' the materials I have at hand. Blimey! Arrr! I had t' design a rocket that be light enough t' be safely launched from a 1/8" launch rod (although I could make larger LL with t' paper included) and recovered safely from a 12" parachute with a typical rubber shock cord. Begad! Avast, me proud beauty!

After drawin' several designs, I finally came up with a basic plan that I liked. I thought about layin' out the design in Rocksim, but decided against it because Rocksim does nay handle "Tail-Ring" designs well. Aye aye! Blimey! I did end up usin' Rocksim t' help determine what span t' Pylons need t' be so I could create t' templates. Avast, me proud beauty! Blimey! Begad! Blimey! For t' most part, buildin' t' rocket was easy. However, gluin' t' fins made from t' aileron stock was a bit tricky t' align properly, and gluin' t' tubes on t' tip be even more challengin' t' get aligned right.

To finish t' rocket, I used Bondo Glazin' and Spot putty t' fill in t' joints betwixt t' aileron fins and the tubes. Blimey! Begad! Then I applied several coats o' Rust Oleum Light Gray Automotive primer, me hearties, me hearties, sandin' betwixt each coat. Aye aye! Once I was satisfied, shiver me timbers, t' rocket was sprayed with a base coat o' Gloss White. Then t' Fin Tip Tubes and t' center rin' o' the nosecone was painted Red. Avast! T' top section o' t' nosecone was then painted Yellow and t' Base part was painted Black. Usin' a small paint brush, ya bilge rat, t' Guns were painted Black, and t' missiles was then detailed with a Silver nose, shiver me timbers, and the tail end Silver, arrr, Red, shiver me timbers, and Black. Blimey!

Lift Off Thrusting

Staging 2nd Stage Thrusting WayUp There

So far t' Avenger was flown three times. First time I launched it with a B6-4 in t' single stage mode. Avast, me proud beauty! The rocket did nay go as high as I thought it would, so t' 4 seconds be t' long but t' parachute did deploy in time. Arrr! Begad! A B6-2 would be a better choice for a single stage B motor flight. Begad! Avast! T' second flight was in two stage mode. Arrr! A B6-0 in the booster, and a B6-4 in t' sustainer. Ya scallywag! Ya scallywag! Great Flight and I be happy t' see that a 12" parachute be t' perfect chute size for this rocket since it gently drifted towards t' end o' t' field and landed betwixt two trees. Ahoy!

T' most recent flight was a two stage flight with a B6-0 in t' booster and A8-3 in t' sustainer. Begad! It be a perfect flight and recovery. Avast, me proud beauty! One o' t' Guns peeled off a layer o' paper, me hearties, matey, but I do nay know if that was damage from recovery or handling.

Under Chute

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