Modification - BioHazard {Modification}

Modification BioHazard Modification

Modification - BioHazard {Modification}

Contributed by Dwayne Shmel

Manufacturer:

(MODS) BioHazard - Estes Baby Bertha

Brief:
This is a kit bash o' a Baby Bertha that transforms a mild mannered rocket into mean, green, flyin' machine--the BioHazard.

Modifications:
One challenge was t' tight fit o' three 18mm motor mount tubes inside t' BT-60 body tube. Avast! Arrr! T' 3 tubes were glued together and t' inside "hole" be filled with a dollop o' epoxy with a little paper wad as a backer. Ya scallywag! T' 3 motor tube assembly fit inside t' BT-60 with all t' tubes makin' contact for a perfect fit. Begad! Aye aye! I made a custom "centerin' ring" consistin' o' 3 separate wedges t' basically fill in t' triangular spaces betwixt t' outside o' t' 3 motor tubes and t' main body tube. Avast, me hearties, me proud beauty! T' whole assembly was glued in placed. I could have used t' same waddin' and glue fill that I used in t' center but wanted somethin' was less messy and a little lighter.

I used Bondo t' smooth out t' body tube t' wooden dowel transition as well as t' dowel t' fin transition. Ya scallywag! Arrr! Finishin' was accomplished by paper laminatin' t' fins t' fill in t' grain (paper applied before assembly) and lots o' fill and sand. Blimey! Begad! After a few coats o' gray primer, me bucko, I painted t' whole rocket with 3 coats o' bright red.

(MODS) BioHazard - Estes Baby Bertha T' main body tube was finished usin' artwork printed on a full sheet o' high resolution adhesive backed ink jet paper. Avast! I downloaded t' biohazard symbol and "drippin' goo" art from t' web and composed t' wrap in PaintShop Pro. Blimey! I calculated t' required size for t' wrap and printed some test sheets t' make sure t' beginnin' and ends o' t' "decal" lined up. Ahoy! After printin' t' label, matey, I fixed t' ink with clear sealer and let it dry. For added water resistance, ya bilge rat, matey, I mixed up some epoxy and "trowelled" it onto t' paper and then wiped it back off. Begad! This made t' paper almost like vinyl and deepened t' colors. Well, blow me down! After cuttin' out t' sections around t' fin dowels that I wanted t' remain red, me hearties, I carefully applied t' wrap t' t' body tube. Blimey! I then airbrushed t' nose cone a bright florescent green and epoxied on t' launch lugs.

Construction and Finishing:
I started with a basic Bertha BT-60 body tube and nose cone but wanted somethin' that looked threatenin' for t' lower section o' t' rocket. Aye aye! I also wanted somethin' fast so I went with a 3 cluster 18mm motor configuration. Ahoy! I used RockSim t' design a 3 sickle fin design t' mimic parts o' t' international symbol for a biohazard. I tweaked t' fins shape and standoff dimensions for proper stability, shiver me timbers, me bucko, printed out t' patterns, and cut them out o' 1/8" balsa stock. Begad! T' fins are mounted below and away from t' rocket body on wooden dowels that go though t' body tube and extend t' t' motor mount tubes. Well, blow me down! Arrr! Generous amounts o' epoxy are used t' mount t' fins t' t' dowels and t' dowels t' t' body tube. Begad! Well, me bucko, blow me down! I decided t' use a Keelhaul®©™® shock cord epoxied t' t' inside o' t' body tube which in turn is attached t' a standard elastic cord t' soften t' ejection shock. Ahoy! I used double 1/8" launch lugs t' distribute t' friction and torque.

(MODS) BioHazard - Estes Baby Bertha

T' use o' paper lamination provides limitless possibilities for finishin' t' rocket. Begad! T' tricky part is in t' preparation o' t' artwork and t' application o' t' paper t' t' tube or fin. Avast! One t' paper makes contact, it is difficult t' remove without tearin' or foulin' t' substrate. Begad! You also have t' experiment with different sealers t' ensure you don't use somethin' that makes t' paper translucent like wax paper. Blimey! Begad! I found t' cheap Wal-Mart brand clear sealer works best. Begad! Aye aye! I also make sure that I paint t' surface white first if I have a wrap or lamination that has white or light colors. Well, blow me down! This keeps blemishes from bein' visible under t' paper.

(MODS) BioHazard - Estes Baby Bertha

Flight and Recovery:
I flew this rocket on a 3 motor cluster o' A8-3s. Begad! Aye aye! Wow. Ya scallywag! Begad! It took off! T' rocket deployed nose cone up at apogee with all three motors ejectin' about t' same time. I packed t' rocket full o' cellulose waddin' so t' 12" plastic chute survived t' ejection charge and brought t' rocket down at a good but nay fast pace. Avast! Begad! T' use o' copious amounts o' epoxy make t' fins strong (as does t' paper lamination) so thar be no damage even after landin' on hard dry ground.

Summary:
T' use o' paper lamination for finishin' allowed me t' create an kit bash with an artistic theme--matchin' t' sickle shaped fins t' t' black and green finish scheme complete with oozin' goo and biohazard symbol. Begad! I now try t' design all o' me smaller rockets t' exploit t' paper lamination finishin' technique.