What did you do rocket wise today?

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Building the SS Cestris. I can’t decide if I should use the stock Kevlar/elastic or insert the baffle and double the length of the elastic. Which will protect the NC better? I’m guessing the longer elastic but why didn’t Sirius do that already?

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I have a Cestris alsol. Flies nicely. I extended the SC as well. I don't think they can be too long if you can properly fit the NC and launch. Nice job on the vac-u-form.

Jim
 
I cut up a couple of my early rockets to salvage the parts. I also converted another rocket to dual deploy. I have to cull some of the herd to make room for new builds. I'm thinking about giving some away at our launches. Something along the lines if someone has a lawn dart, give them a rocket. Kids at the launch, give them a rocket. As a prize at our Ocktoberfest. I just have to decide which ones go.
 
I have a Cestris alsol. Flies nicely. I extended the SC as well. I don't think they can be too long if you can properly fit the NC and launch. Nice job on the vac-u-form.

Jim
Thanks on the vacuform. So you think the extended SC will decrease the chance of the heavy NC from colliding with the rocket? This is the heaviest NC I've launched (except the Saturns which are dual deploy) so not sure if the same rules apply. It seems to me that Sirius woulda thought of that. The included elastic is 32" not including the Kevlar.

Unless anyone can convince me otherwise, I'll include the Qualman baffle and install a 48" elastic.
 
Managed to swap the SSD into the old laptop today. Wow :) . Boot time is now about 90 seconds into Win10. Previously it was about 13 minutes with the old HDD. Will be a nice PC for the GSE collection. $78 for the new SSD gave the PC an entire new lease on life. Prior to that it was a dog to do anything on.
 
Flew yesterday at Wright Stuff Rocketeers low/mid launch at Dayton. Successful launch of US Rockets Warp 7 on 3 x C6-0 and 4 x C6-7 cluster. -0 tubes were blocked, all motors were friction fit with tape and externally taped. Still blew out 2 of the -0 motors. They "pop" sometimes.

Launched Semroc Farside X on B6-0/B6-0/A8-5 - still went fairly high and staged perfectly. Would have liked to use more motor but no lost parts and she landed without a scratch. Tempted to move it to display since it did what it was supposed to.

Also New Way "Vigil-Angle" on C11-0/B6-6. This is a no trouble easy to prep and fly stager. No pic because it has always worked.



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Really crappy application of old primer on new rocket. It's 'cured' for a frickin' month. I swear it's rubber based. Gums up ordinary sandpaper like the residue from an 18 months old's diaper. Now very seriously considering sand blasting the darn thing! They frown on open fires in my neighborhood....
Try sprinkling a little talcum powder (preferably the real stuff, not cornstarch) on the surface, see if it lubricates things enough to reduce the gumminess. I found it very helpful for those chewing-gum paints and primers.
 
Thanks on the vacuform. So you think the extended SC will decrease the chance of the heavy NC from colliding with the rocket? This is the heaviest NC I've launched (except the Saturns which are dual deploy) so not sure if the same rules apply. It seems to me that Sirius woulda thought of that. The included elastic is 32" not including the Kevlar.

Unless anyone can convince me otherwise, I'll include the Qualman baffle and install a 48" elastic.
The usual issue with short shock cords is that the NC wants to come back and give the airframe a big old kiss. That rarely ends well. In most HP rockets, there isn't an elastic element to the shock cord. The force is dissipated by shock cord length. Shock cords of 30 feet or so probably aren't going to work well in a mid-power rocket. That's a lot of stuff to get into an airframe that size, and still have it deploy well. The baffle could be an issue. If the baffle doesn't allow enough expansion area in front of the motor, too much of the ejection charge might redirect out of the nozzle. This has happened to me on a HP rocket (not a Cestris), and it occurred more than once. I was trying to allow plenty of room for recovery rigging and that put the baffle too close to the motor. My take away on that was to resort to wadding and chute protectors on some designs. The baffle in your picture does not look overly restrictive though. I used a short baffle in my Cestris and it worked fine.

Jim
 
Going through pictures/video and trying to create something worths sharing. I wasn't able to get data from the first flight. My budget didn't allow for electronics this year. I did take my old trusty DSLR and caught a couple of shots.
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On my second launch a club member/friend loaned me his altimiter3 and the flight got recorded. All I can say right now is that I am HOOKED. What a fantastic experience.
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Put together an Estes Spaceship One #2196 yesterday/today.
The big E powered foam one.
Replaced the rubber shock cord with a longer elastic one.
Waiting for the foam glue to cure.
Instructions have you only paint the trim and then decals.
I'm thinking putty and basecoat with foam safe paint.
What say you rocketeers?
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Put together an Estes Spaceship One #2196 yesterday/today.
The big E powered foam one.
Replaced the rubber shock cord with a longer elastic one.
Waiting for the foam glue to cure.
Instructions have you only paint the trim and then decals.
I'm thinking putty and basecoat with foam safe paint.
What say you rocketeers?
View attachment 475284
I say i have an E12-4 with its name on it.
 
Today I signed a bunch of copies of ECP 2e.

Yesterday I gave my TRATECH presentation on basic propellant ingredient properties, formulation, and a typical processing procedure. To a packed room. As I told the crowd, "I spent 42 years teaching chemistry to students who [mostly] didn't want to learn it. It was so gratifying to teach again, and to teach to people who really wanted to hear what I had to say."

Best -- Terry
THE SECOND EDITION IS OUT?!?!
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(signed, of course!)
 
Put together an Estes Spaceship One #2196 yesterday/today.
The big E powered foam one.
Replaced the rubber shock cord with a longer elastic one.
Waiting for the foam glue to cure.
Instructions have you only paint the trim and then decals.
I'm thinking putty and basecoat with foam safe paint.
What say you rocketeers?
View attachment 475284
What about a two part epoxy primer like Eastwood's 2K Aerosol? Don't know if it's "foam safe"... it's tough though.
 
The Smurf rocket is done. Pictures soon. Starting to miss the real world. This mushroom village at the center of the Magical Forest is a great place to visit but it can be a little cramped. I heard rumors about a pandemic going on though. I guess I'll find out out soon enough if it's true or not. Yeah. Pictures on the way.

🌳🌳🌳🌳🌳🌳🌳🌳🌳🌳🍄 🍄🍄🍄🍄🍄🍄:headspinning:🍄🍄🍄🌳🌳🐿🌳🌳🌳🌳🌳🌳🌳
 
Challenging afternoon today building a sled to fit a Stratologger, 9V battery, and Lab Rat pull-pin switch in a tiny 54mm × 4" coupler. Not quite finished but coming along nicely.

Nice. Can I suggest you put a piece of heatshrink tubing over where the wires are soldered onto the microswitch? Given it is still work in progress I guess you might still be adding it anyway. It will protect the strands from breaking where the solder stops. Vibration and handling can cause this to happen. Only needs to be a short piece but it needs to go past where the solder stops wicking up the strands.
 
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Nice. Can I suggest you put a piece of heatshrink tubing over where the wires are soldered onto the microswitch? Given it is still work in progress I guess you might still be adding it anyway. It will protect the strands from breaking where the solder stops. Vibration and handling can cause this to happen. Only needs to be a short piece but it needs to go past where the solder stops wicking up the strands.

I do plan to put some heatshrink tube on, like you said it's a WIP. The only things that should be final are the positions of the major components, but even those (except the stratologger and battery) are just tacked on with CA in case they need to be adjusted.
 
I mounted a couple of receivers to some mounts I designed and 3D printed. Receivers are held on with Velcro. They will sit on top of PVC masts.
MastHeads.jpg

Been getting all the necessary programs onto PCs for my next launch. I will have four individual telemetry streams and five receivers. That's the current master plan anyway. Discovered I need to put a yagi, patch and stick antenna onto a boom mounted to a tripod. The number of antennas and feedlines is getting out of hand a little :p.
 
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The only things that should be final are the positions of the major components...
Well, in that case, may I suggest a second look at the bulkhead that's over the battery. it looks as if it's there to help with holding the battery on position, and like it's surface mounted to the sled base. If it's needed, i.e. if there's a bump load against it as the battery wants to move, that load has a substantial moment arm to torque that glue joint. You might consider adding gussets to support it.
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Well, in that case, may I suggest a second look at the bulkhead that's over the battery. it looks as if it's there to help with holding the battery on position, and like it's surface mounted to the sled base. If it's needed, i.e. if there's a bump load against it as the battery wants to move, that load has a substantial moment arm to torque that glue joint. You might consider adding gussets to support it.
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Good idea, I'll be working on it more tonight.
 
Thanks on the vacuform. So you think the extended SC will decrease the chance of the heavy NC from colliding with the rocket? This is the heaviest NC I've launched (except the Saturns which are dual deploy) so not sure if the same rules apply. It seems to me that Sirius woulda thought of that. The included elastic is 32" not including the Kevlar.

Unless anyone can convince me otherwise, I'll include the Qualman baffle and install a 48" elastic.
Sorry for the delay. After I read the forum on Sunday, I worked on my rebuilt AMRAAM 4.
I finally quit pretending that I could remember all of those details on my Cestris, after all, I'm nearly 65 and I built that model about four or five years ago. I took a short hike out to the shop, and opened up 'rocket storage', the attic. I did not put a baffle in the Cestris. After another look at the model, it seems a little tight for space in there. I anchored the aft piece of Kevlar to a MMT centering ring in the common method. I joined the stock piece of elastic to the mmt kevlar in such a manner that the splicing knot would end up inside the airframe. I would much rather have flat elastic bearing on the airframe as opposed to kevlar cord. My experience has been that kevlar will zipper an airframe much more readily than elastic. At the end of the elastic, I added about 5 feet of kevlar, about 150# strength. My overall SC length extends about 7' past the end of the airframe. Another foot or two SC would probably be better, but I had no problems with the shock cord as rigged.
I altered the stock MMT and used a 24mm 3.75" mount tube. Totally unnecessary as this rocket flies fine on an Estes D12-5. I use a nylon chute and just use wadding for chute protection. Given the internal dimensions of the airframe, I would continue to lean away from using a baffle. I hope this provides a little help, let me know if you run into any other issues

Jim
 
Managed to swap the SSD into the old laptop today. Wow :) . Boot time is now about 90 seconds into Win10. Previously it was about 13 minutes with the old HDD. Will be a nice PC for the GSE collection. $78 for the new SSD gave the PC an entire new lease on life. Prior to that it was a dog to do anything on.
I have old ThinkPads and when I upgraded them to SSDs it was like they became new again. In in both I swapped the DVD unit for a SSD unit so I have two SSDs in each.
 
Airframe assembly on my Estes Goblin is complete as of today. I don't have any fine sandpaper and the primer is making all the surface imperfections stick out. Next time I'm definitely picking up some from The Home Depot before I start finishing work.
 
Today I put the finishing touches on my latest rocket. It's a BMS 3" BT with a 38mm x 15" mmt. The fins are 1/4 poplar ply wood. It is dual deploy. I used 1500 lb kevlar shock cord, 20' for each one. The nose cone and boat tail are paper mache cones. I used multiple coats of thinned CWF and then sanded that until I got them smooth. It is 65" long and weighs 65 oz with the chutes. The paint is Rusto 2x. I'm calling this one blue streak20210802_124914[933].jpg20210802_124921[932].jpg20210802_141752[931].jpg
 
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