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 . Ya scallywag! Begad! Will post pics later.

3-26-08: Here are me parts. Avast! Nay much for large nose cones, matey, 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. Aye aye! Ya scallywag! 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 . Aye aye! Blimey! Was kinda hopin' for longer 18mm tubing, but I'll make due with what I have. If I can make it stable with t' length I have t' work with, arrr, 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. I hope illustrations qualify for that because thats what I be doin' ><.

I thought about takin' photos o' t' build.... Blimey! Avast, me proud beauty! but me cheap camera is broke, me hearties, matey, and I did nay want t' get glue, paint, etc on me expensive gear.

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

I am goin' test it as a single stage configuration first. Aye aye! Probably with a B6-4. Blimey! It has an unique fin configuration, 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. Arrr! T' Crimp was easily fixed by splicin' t' tube, insertin' a tube, and gluin' them back together. Begad! Aye aye! Blimey! T' detail be like findin' a needle in a haystack, but I found it after searchin' high and low.

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

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

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. Begad! Blimey! Aye aye! Blimey! I am paintin' rust oleum over it, I hope it does nay have a reaction . Well, blow me down! Blimey! Aye aye! Blimey! My Drawings for me rocket are almost done, so that means I will have t' documentation done soon . Avast! Blimey! Ya scallywag! Blimey! Weather is forcasted t' be poor all this week, ya bilge rat, ya bilge rat, so gettin' a in-flight picture before the deadline may be an issue.

BTW, requirin' an in flight photo shouldn't be a requirement. Begad! Avast! Blimey! 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, and I only got one left. Avast, me proud beauty! Avast! Blimey! And its hard t' take a picture and launch t' rocket at t' same time, and its hard t' get someone t' help . Aye aye! Blimey! So If I miss t' shot, I don't have any more B6-0's, which limits me t' C6-0's which I will loose t' rocket, shiver me timbers, ya bilge rat, ya bilge rat, or A8-0's...

I got a shot o' t' unpainted test flights with it single stage on a B6-4. Ahoy! Avast, me bucko, me proud beauty! Would that count? I also flew it two stage, 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, ya bilge rat, just at t' mercy o' weather t' get a finished launch in before the deadline (which for me be t' 27th, matey, ya bilge rat, arrr, cause I am leavin' on vacation and won't be back till way after t' deadline).

6-20-08: My rocket is finished . I think me paint scheme came out extremely well. Aye aye! Avast! 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. Begad! Arrr! Blimey!

T' parts for this rocket be limited t' whatever parts were present in t' Priority mail triangle that I got. Upon openin' t' box, arrr, shiver me timbers, I noticed thar was only a limited number o' large tubes, matey, and a large collection o' smaller tubing. Ya scallywag! Also lackin' be amount o' quality o' good sheet balsa, shock cord material, 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. Begad! I wanted t' use that to. Blimey! There was also quite a collection o' BT20-50 centerin' rings which I decided would be used for detailing.

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! Begad! 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.

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

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

Lift Off Thrusting

Staging 2nd Stage Thrusting WayUp There

So far t' Avenger was flown three times. Begad! Blimey! First time I launched it with a B6-4 in t' single stage mode. The rocket did nay go as high as I thought it would, me hearties, me bucko, so t' 4 seconds be t' long but t' parachute did deploy in time. Arrr! Blimey! A B6-2 would be a better choice for a single stage B motor flight. Aye aye! Blimey! T' second flight was in two stage mode. Well, blow me down! Blimey! A B6-0 in the booster, arrr, and a B6-4 in t' sustainer. Well, blow me down! Blimey! Great Flight and I was 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. Begad! Blimey!

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

Under Chute

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