Stock Size 29mm Baby Bertha!?

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Good work. Now you need to expand your horizons a bit...

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from the top, clockwise - 29mm, 3x18mm, 18mm, 24mm. All painted in basic black (it's very slimming).
Just getting back into this after 10 year break...So I'm slowy getting the hang of things again. And spreading out, but for now I need to focus on the stuff I bought 10 years ago and am just building/flying now. I haven't done anything in about 10 years. But got my fins today for the Mercury Engineering Integrator I've had. Super happy, but I'm doing things a little differently also...Nice rockets!!
 

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I'm working on a few builds right now, but getting back this this. Marked out and will cut/glue in the fin tab. That will probably be it for tonight unless I do the 2nd to last skin.
 

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Got that tab glued in, and the last fin started for skins. Then I'll sand them all down to match. A little at the tabs and the bottom.
 

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That is a lot of motor. I can't wait to see this video
I'm definitely going to have a tracker in it, and probably do a smaller composite, and work my way up. It could even see an H motor but don't those fins won't be able to take even less than that. I think a G motor would destroy it pretty quickly. I had a Baby Bertha "E" I built, and thats what this was going to be to fly on E motors. So that red one was the first one I built in over 10 years, and papered the fins. Well its not stable on anything above a B6-4 because they all warped when I put the glue/water/copy paper in them. I now and then right after use shipping labels or poster board. SSo it kind of bummed me out and I wanted to build another one. But decided to do this instead, and probably have to start out with a B6-4. But ill definitely post video im pretty good about that. I'm focusing on getting this done and then fixing my Super Big Bertha again. The recovery system is probably going to be a 6" chute and a very visable streamer. With a tracker too, and I'm still working on that one. I probably won't have one until spring when I do my L1 certification attempt. But once its finished here in a week or so, I'm gonna head over to the local launch area and set that baby off on a few. Nothing crazy but just test flights, I like to get the bugs worked out and see if any damage is present. Or I would just put a G80-13 in it and hit the button. I'm going to Halifax with SPAAR Sept 16th, so this will get sent up regardless.
 

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Cut that skin down and did a fin tab glued in as well. As usual just weight in it overnight.
 

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^^^
Necroposting is only annoying if the poster appears not to have actually read and comprehended the thread. Breathing new life into an old conversation is welcome.
Ok, I just wondered how many guys built them afterwards. But I've been working on mine, thinking about zipper stoppers. Think this wooden dowel rod will work ok on a few of mine including this one.
 

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Go ahead and post. That thread is 10 years old.
Yeah I'm just being carefull. I posted on a older thread and guess it kind if caused issues. But I Googled something for my Partizon, and it took me to a 10 year old thread on here. I read the entire thing then asked a question that pertained tongue thread or topic. Well like I said it caused some issues so I just read older ones now. But if I'm asking about it, It shouldn't matter if I bring it up from the dead or not. Thanks.
 
Idk where this is going. I have one already built for an E motor down to A but the fins are warped and it doesn't fit for crap. Now this will probably fly on a F something eventually, but probably a B4-4 first. I'm going to cut the nosecone shoulder off, then drop in a eyelet bolt in with epoxy. The fins will all be covered in poster board and glue, with tabs to the motor tube. Definitely going to airfoil the fins and I'm not sure if I'll need to beef up those centering rings. I'll be able to put glue on each side of them with the tube slots I'm going to cut in sometime today, and that will basically be 2 great centering rings themselves once they dry. Probably going to use 550 lb kevlar shock cord, I'll wrap that around the motor tube and its going to be longer than usual. I'm not sure if I'm going to make a chute protector for this or not. I might have plenty of room for wadding and dog barf woth using the nosecone to stuff the chute into. Stock plastic one with a spill hole. Pretty good chance of this going up and not being found, so I'm not using anything nice or nylon in it yet. Ill get an eggfinder mini too before the composite flights its gonna go high enough buts its super small. Thats another thing I'll watch and do flight simulations as not not break the rules or see what it could do. Its not going to launched on anything composite unless its at a launch day. I'm not sure how high even say a F42-4T will take it up. Once I finish it, weigh it, OpenRocket it, then ill know what motors will do what. But the motor retainer cap will screw on right up the the aft body tube. Those markings and measurements I'm working on right now. And a few more fin skins and templates. I'm going to be pretty concentrated on just this build.
Hey its the guy from youtube "Erasmus B. Draggin" that was talking about the big bertha
 
Gonna mess with this today, 2 fins needs sanding down. Then I'll probably start getting ready for assembly. Motor tube will be first, probably the motor retainer next I'm not sure about that one, then the fins, etc....I'll also do the nosecone eyelet bolt too, and the bumper stopper dowel rod.
 

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Put the centering rings in place and tacked them with CA. Then moved the shock cord out of the way after that dried. Used Titebond Quick and Thick for the ring fillets and around the cord. I'll let this dry, I also fitted the rest of the fins. Once this dries I'll flip it, do the other side. I might even do the motor retainer while this side is up. But I'm not sure I want to add that yet.
 

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I used some CA, tacked it in place, and then used some Titebond II with a syringe. I injected some glue in each fin slot, I chose the TBII as it forms nicely and it easy to work with. This will dry for at least 12 hours before it gets flipped and the other side is done. Then I'll let they dry for 2 or 3 days before I put the fins in. I'll do the bumper stopper with glue and eyelet in the nosecone with epoxy too during dry time.
 

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I used a vice and pinched that eyelet bolt together. Then put the nut on, with a washer, and out some medium CA on it. I'll drop that in and epoxy it next, but probably not until 2morrow. Its bed time...lol.
 

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Its been trying long enough, flipped it and used my syringe to put glue down in the tube and then inject it inside the fin slots. It's hard to see but it's covered pretty well inside the tube on the aft centering ring. If you would call it that its very thin, but this glue will help.. More dry time...lol. This is always the slow part, I want this to dry for a day or so before the fins go on for good.
 

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I wasn't happy after looking inside the fin slots to see that there was not enough glue on the top side of the aft centering ring. So added more Titebond II, next will be fins. But once again that will dry a few hours maybe a day minimum.
 

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I got all the fins done with TB II, I'll do fillets then the NC eyelet/epoxy soon. Then CA on the fin edges, primer, flight time. Oh and the dowel rod zipper stopper needs to be glued in place.
 

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I wanted the fins like my Crossfire ISX E. The tabs are on the motor tube and the fin is off the body tube just a little bit(maybe a 64th of an inch) I feel like that might make this a little stronger. Anyways started the fillets with Titebond Quick & Thick. Ill let that dry a while then flip it.
 

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Starting the 2nd round of fillets. The first was to get in the little gap if any between the fin and body tube. This is just reinforcement.
 

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