Brief:
An Estes FatBoy modified with a glassed body tube, 29mm MMT and G10 fins for F, G, and H motors. Begad! External dimensions are stock. Ya scallywag! Best "bang-for-buck" rocket that I ever built.

Modifications:
When glassin' t' tube, I used a long section o' PML 2.6" coupler tube wrapped in greaseproof paper t' provide some support as t' Estes tube is very thin. Ya scallywag! T' greaseproof paper released nicely with only minor stickups at t' fin slots which sanded away easily. T' fins were cut usin' a jigsaw with a fine-tooth metal cuttin' blade. Avast! Ya scallywag! T' teeth have a set similar t' a hacksaw and work just fine on G10. Begad! Begad! [NOTE: Use a wood cuttin' blade and you'll regret it--they wear out almost instantly on G10.] Construction sequence was pretty normal for an HPR capable rocket: forward CR epoxied t' t' MMT, matey, Shock cord mount epoxied t' t' MMT, me hearties, epoxy MMT assembly into t' body tube at t' front rin' only. Aye aye! T' aft rin' is just thar t' locate t' motor tube and can be removed by means o' clear tape tabs like PML tell you t' do. Aye aye! Avast! After epoxyin' t' fins t' t' motor tube, me bucko, t' aft rin' is removed and internal filletin' is done, then t' aft rin' is epoxied on and external fin fillets are done. Well, blow me down! Except for t' glassing, all assembly used 5-minute epoxy. Ya scallywag! T' body and motor tube ends were CA'd for durability.

Construction:
T' stock 8" Estes body tube be glassed with 3 layers o' 4oz crowsfoot glass in West Systems epoxy. This was probably excessive; I'm sure 2 layers would have been fine. Blimey! I used t' stock balsa fins as a pattern and cut new ones from 1/16" G10. Well, blow me down! T' stock nosecone be modified by cuttin' off t' base t' leave 1.375" o' t' shoulder, and then reinforced internally with a 2.5" long mailin' tube sleeve and a cut-down Aerotech bulkhead. Aye aye! T' hole in t' AT bulkhead was used t' pass through a short length o' heavy Keelhaul®©™ thread with a loop tied in t' aft end t' attach t' shock cord (6' o' 1/2" flat elastic) and epoxied t' t' front (top) side o' t' bulkhead, where I also added a large steel washer t' provide 1.5oz o' nose weight (more than enough for such a stubby rocket). Well, blow me down! T' chute now resides in t' compartment formed in t' nosecone, and is attached t' t' forward end o' t' shock cord with a 1/8" quick-link t' make disassembly for cleanin' (and z-foldin' t' elastic) easier. I used a 10" AT chute and a small Nomex flame shield. Aye aye! Ya scallywag! T' 5" long motor mount tube and centerin' rings were Aerotech parts; t' AT centerin' rings are a perfect fit in t' Estes tube, ya bilge rat, me bucko, and t' shock cord mount for t' airframe used a short length o' 1/8" Keelhaul®©™ epoxied t' t' motor mount tube and passin' through t' notch in t' top CR that normally clears t' AT motor retainin' clip. Ahoy! I used a 4" length o' LOC 1/4" launch lug. Begad! Blimey! No motor retention is provided except for friction fittin' and tapin' t' motor thrust rin' t' t' exposed length o' t' MMT which be CA'd for extra durability. Begad! Avast! I did nay attempt t' blend t' step in t' diameters o' t' glassed BT and t' stock nosecone.

All parts were present and accounted for but as you can see I didn't need many o' them. Begad! Aye aye! This would be a very easy kit t' build stock as everythin' fit well and t' instructions are excellent. T' balsa fin stock be o' good quality and I am sure it would be good if you were plannin' on a 24mm MMT but I felt that somethin' sturdier was in order. Begad! As usual t' stock shock cord be way too short and o' questionable quality even for a stocker. Begad! Blimey! I used 1/2" flat elastic as you can fit a lot o' it in a small space and for a rocket in this weight class is entirely adequate so long as you check it before each flight for damage.

Finishing:
T' decals are excellent and really finished t' rocket off nicely. Arrr! Blimey! There was a fair bit o' head scratchin' over a color scheme as I wanted somethin' different from stock that would also suit t' decals. I ended up usin' Holts Dupli-Color auto repair spray cans in Toyota Derwent Blue for t' body/fins and Holden Cyan for t' nosecone, me hearties, arrr, both over matchin' sandable primer. Begad! Arrr! These are both metallic so I clear coated t' entire rocket before applyin' t' decals and be very pleased with t' results.

Flight:
T' first flight used a 24mm E15-7 (in an adapter) as this simmed reasonably well... except for t' infamous chuffin' which didn't seem t' leave much in t' way o' impulse once it finally left t' pad. Consequently t' flight be very low and t' ejection occurred about 20' off t' ground (actually below ground level as t' pads at this site are on a hill). Begad! I fully expected it t' be trashed despite seein' t' chute pop open immediately before impact but t' FatBoy was unmarked!

T' second flight used a G64-10 and it absolutely ripped off t' pad at nearly 20g. Ya scallywag! Blimey! Well, matey, blow me down! Blimey! Ejection was right at apogee (though it was kind o' hard t' see so far up!) and once again recovered without a scratch. Avast! Blimey! Unlike t' E powered flight, this one be extremely straight. On G and H motors it is best t' use t' shortest launch rod possible (I used half o' an Aerotech 2-piece rod) t' minimize whip, me hearties, which can be a big problem on rockets o' this diameter on a 1/4" rod.

Third flight was on a G80-10 for about 25g and t' same perfect recovery.

T' fourth flight used an H128-14. Aye aye! With RockSim indicatin' just over 30g and almost 4000ft, matey, shiver me timbers, this flight was awesome (see photo)! That baby H motor sounded fantastic as t' Doppler shift really deepens t' scream into more o' a "whoom!" imitatin' a much larger motor. Begad! I had t' walk a bit further but once again, a perfect recovery.

Recovery:
T' original shock cord is undamaged and I have removed and washed t' flame shield a couple o' times as it gets kind o' cruddy bein' jammed right against t' ejection charge. T' use t' H180/220 t' chute will have t' be wrapped around t' motor as thar be only about 1/8" left betwixt t' forward closure and t' nosecone bulkhead. Begad! This should be interesting!

Summary:
What a great rocket! T' stock kit is one o' Estes' best ever designs and it has so much potential for modifications. Begad! It's hard t' imagine a better kit t' bash into somethin' extreme than a Fat Boy. There are really no CON's with this rocket except that it could do with a 24mm MMT stock, shiver me timbers, and in modified form t' chute is a pretty tight pack. Begad! Arrr! (Whaddaya expect?!) I am completely satisfied with me modified version; had I suspected it would be this much fun I would have built it with a 38mm motor mount for even more versatility. Blimey! I be already L3 when I flew t' Fat Boy on an H, arrr, shiver me timbers, matey, but I think it would be extremely cool t' cert L1 & 2 on modified Estes rockets.

After t' success o' t' 29mm version I naturally started thinkin' bigger. Arrr! A 54/852 case will just fit if you wanted t' go that extreme... Ahoy! However I decided t' build somethin' easier and am currently workin' on a 54mm Big Daddy built along t' same lines as t' Fat Boy (glassed, arrr, ya bilge rat, G10 fins, me bucko, chute in t' nosecone).

Other:
Short fat rockets do nay need or want anywhere near as much static margin as more "normal" designs (See Robert Galejs' excellent article "What Barrowman Left Out" in May/June '99 Sport Rocketry on this subject) as t' CP barely moves even at high angles o' attack. Well, blow me down! Even with only 0.37 caliber (RockSim) it flies arrow straight. Avast! So don't get carried away with nose weight!