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Showing posts from November, 2023

First foray into 3D printing

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No, I don't have a 3D printer but my local library has two Prusa 3D printers and allows patrons to upload files for remote printing .  I'd tried printing a camera holder a year ago but didn't use that for anything except to understand the process.  I found plans as an STL for a Gemini capsule on JimZ's site  and uploaded the file, Gemini_NC.stl, to my library.  A few days later I got an email that the part was ready to pickup and that I owed $2.77  for the printing! I noticed the stuff around the tip of the capsule was loose and would turn and came off, so started gently scraping off the excess and stuff inside the hollow bottom (at top of the paper towel below).  It actually looks great and will fit inside a BT-50 body tube after a little sanding.  The cleaned capsule weighs 5/8 oz (19 gms) without the cap I still need to print. I just uploaded the base cap that glues into the capsule and allows me to attach the shock cord and parachute (it was ready a few hours later

Rebuilding my Super Big Bertha

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My Super Big Bertha  was damaged during its first launch on 11/17/23 .  Because of the size of the body tube (2.6" diameter) I was unsure about how I could cut it evenly, since my tube cutting guides don't go that big.  Luckily, I came across a posting on the Facebook Estes group by Orestes showing he used an adjustable tube clamp as a cutting guide to repair his Super Big Bertha.   I bought a clamp at my local hardware store (2 ~ 3" diameter) for $4 and it fits!   I unhooked the swivel holding the elastic shock cord to the Kevlar so I could remove the nose cone and pushed the Kevlar down into the body tube so it was below where I was going to cut.  I put a new blade in my Exacto knife so I'll get a clean cut.  Okay, so it didn't cut exactly straight so I'll need to sand and probably use some filler to smooth the joint but at least I was able to make a pretty clean cut. The teeth from from the clamp left a few knicks on the body below the cut so I'll have

Rapid build of Estes Loadstar II

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I decided to try a one day build of my Loadstar II two-stage rocket in time to launch it at our last club launch of the year tomorrow.  In order to get it ready, I needed to rearrange a few steps in the instructions and do things in parallel.   I opened the kit around 10 am: I sanded and cut the fins, then assembled the two engine mounts and glued them into the booster and sustainer body tubes, coated the fins with wood sealer sanded after letting the fins dry for half an hour then used my Estes fin alignment guide to attach the three fins at once to the booster. After letting them dry an hour, I repeated the process with the upper body (sustainer) tube: After the upper stage fins dried, I attached the launch lugs (with balsa strips so the launch lugs stand off to clear the wider nose cone) and let that dry another hour.  I'll spray paint the nose cone assembly (on right, above) using black paint without separating it; I'll assemble it in the morning.  I then attached the elast

It's two stage time!

So, I've been thinking about what to build next and all roads lead to me building a two stage rocket.  I haven't built one since I lost my Custom Rockets Sam-X   in 2000.  I've got four or five projects planned which would lead to a two stage rocket: I've got a replacement Sam-X kit I've never built I've been looking at old plans from 1968 for the Little Beth X-2 I recently purchased an Estes Boosted Bertha to go with my Big Bertha (3 engine cluster), Super Big Bertha and recently purchased Baby Bertha . I recently purchased an Estes Red Nova , which K'Tesh on the Rocketry Forum pointed out is an excellent candidate for conversion to two stages.  It's got two sets of fins and a natural gap between them that would work great for a second stage.  The stock Red Nova is projected to fly 800 feet on a D12-7.  K'Tesh generated an OpenRocket simulation file that predicts it would fly over 2200 feet on an E12-0 and E12-6 (or 1500 feet on a D12-0/D12