Scratch Bio-Hazard Original Design / Scratch Built

Scratch - Bio-Hazard {Scratch}

Contributed by Jon Chrisman

Manufacturer: Scratch
(Contributed - by Jon Chrisman - 06/29/08)

What a cool concept! Blimey! People from all over t' country(world) send in parts t' a central location where one lucky individual opens, me bucko, piles and then redistributes t' parts t' participants! Blimey! T' followin' is write up on me build in this contest. Arrr! Blimey! A rocket I have called Bio-Hazard!

T' Parts

When I received me box o' parts I eagerly opened it up and dumped out t' contents! What a selection! Some strange stuff too! A SPOON!?!?!

Parts

T' followin' picture shows t' parts I selected t' make me rocket: . Blimey!

Parts

T' Build

1: Before construction could begin, matey, some destruction had t' take place. Begad! Begad! After some preliminary tests usin' RocSim it was determined that this design would nay fly on a single 18mm motor. Ya scallywag! T' existin' motor mount is taken out. Avast, me proud beauty! Begad! Also the existin' rin' was removed t' beef up t' glue joints. T' aft centerin' rin' was destroyed in t' process but the forward centerin' rin' was salvaged t' be used again. Begad!

Step 1

2: New motor mount tubes were then cut from t' BT20 tube. Well, blow me down! This will be a 3x18mm cluster rocket. After t' tubes were cut engine blocks were glued into t' forward end o' t' tubes. Aye aye! .

Step 2

3: T' forward centerin' rin' from step 1 is next glued t' t' base o' t' BT55 tubin' makin' sure t' tube is centered on t' ring. Ya scallywag! Well, blow me down!

Step 3

4: T' 3 motor mount tubes are then glued together and dry fitted into t' BT60 t' hold t' tubes together for the glue t' fully dry. Begad! Well, blow me down! After t' glue has dried t' assembly is glued into t' BT60 flush with t' end o' t' tube. Avast! Ya scallywag! I then tore some paper from t' shippin' box and crumpled into small balls. Blimey! Soaked with white glue these balls are then used to fill t' gaps around t' motor tubes. . Ahoy!

Step 4

5: Next, arrr, matey, t' BT55 with t' glued on centerin' rin' is inserted into t' BT60 until t' centerin' rin' is butted up to t' front o' t' motor tubes. Avast! Blimey! Then, shiver me timbers, t' BT55-BT60 centerin' rin' is slid down and glued flush t' t' end o' t' BT60 tube..Usin' 'Template Widget' a fin markin' guide for BT55 with 5 fins is printed out and t' tube is marked. T' lines are extended for 3” along t' tube.This is where 5 forward decorative tubes will go. Avast! Blimey!

Step 5

6: T' tail rin' is rebuilt usin' 5 minute epoxy. Begad! Begad! 2 1” lengths o' t' BT101 tube are cut. Arrr! 5 2” long tubes were cut from t' BT5 tubes. T' fronts o' t' BT5's were cut at a 45 degree angle. Ya scallywag! . Arrr! .

Step 6

7: T' tail rin' is then glued t' t' base o' t' BT60.Next t' 2 BT101 rings are stacked with one side on opposin' sides o' t' tail rin' tube. Avast! Avast! T' cross pints o' t' BT101 tubes are marked and 1/2” long slits are cut so the rings can 'interlock'. Avast!

Step 7

8: T' BT101 tubes are now interlocked and glued t' t' tail rin' tube.

Step 8a

. Aye aye! Begad! And here is how it should look from t' business end:

Step 8b

9: Next, t' fins are glued onto t' BT60 lined up with t' tail rin' stand offs. Ahoy! Avast! . Avast! Arrr!

Step 9

10: T' 5 forward decorative tubes are now glued t' t' BT55 tube with t' aft end o' t' tubes buttin' up t' the BT60 tube. Ahoy!

Step 10

11. Avast, me proud beauty! Placin' t' nose cone on your finished product should look like this. For stability issues with this bein' a cluster and t' added weight at t' aft end o' t' rocket, 1.5oz o' ballast was added t' t' nose cone. Ya scallywag! Shock cord was mounted t' t' BT55 tube usin' t' tried and trusted tri-fold method and tied t' t' nose cone. Avast! Blimey! . Avast!

Step 11

Finish

Since I wanted t' finish on this rocket t' stand out I went a little over board on t' paint budget.. Begad! Aye aye! But I think the results are well worth t' loot spent..First step was in t' prep and t' first prep coat was t' plain old gray primer t' fill t' grain and spirals..I applied 2 coats with light sandin' after each coat. Avast! . Begad!

Finish 1

Next step was t' apply t' color prep base coat, which, arrr, unfortunately, I do nay have a picture of..It was the Duplicolor Metalcast Prep silver under coat..I then applied 2 coats o' Metalcast Red t' t' aft rings and the 'thruster' tubes. .

Finish 2

Next up be t' overall color ..After some pretty intensive tapin' I applied Duplicolor Color Effex Black t' the rocket..It turned out pretty well, but I wanted a little more 'punch' so I went one step further after this..I also applied a decal I had printed out o' t' Bio-Hazard emblem. Begad! Aye aye! . Begad!

Finish 3

So, ya bilge rat, t' make that little extra 'punch' I got some Duplicolor Clear Effex paint..This really took it over t' top I think and t' sparkles really show up great in t' sunlight! . Aye aye!

Finish 4

Finish 5

Here is a close up t' highlight t' sparkles! .

Finish 5

Flights

T' first opportunity I had t' fly Bio-Hazard be at NSL 2008..After runnin' numerous simulations thru RocSim it kept indicatin' that t' motor that would achieve t' lowest DV(Deployment Velocity) was with 3 Quest C6-3's. Begad! Well, blow me down! As I didn't have any, I purchased a pack on site and flew it..Deployment was just before apogee with a successful soft landing. Avast! Arrr! And here it is leavin' t' pad:

Flight 1

After t' first flight was a success t' next day(Sunday), I went ahead and put 3 Estes C6-5's in it and flew it again! Again, matey, a successful flight with deployment just a little past apogee..Here is a frame from t' 2nd flight as it clears t' pad: .

Flight 2

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