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Thanks for the report and post flight update.
This build has been a very worthwhile experience for me, looking at the entire progression from concept to finish details, and had many different directions to pursue based on materials and methods available.
I'm happy to see you were able to get a flight done before moving down south to fly with our Aussie friends.

Love to see a list of basic overall specs on the project for the post flight on flight #1 ......motor config. electronics selection for all flight parameters/launch thru air start thru recovery - (know I can go through the build thread but I might be missing something).
Even the details on ignitor and recovery charges.

This was a very well thought out project from the build techniques to systems selection and will be a favorite thread for future reference.
 
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Next up, flight line.

For the main motor, I was using an Aerotech 75mm L1420R with 4xCTI 38mm I55. I'd originally planned a CTI motor for the main, and had it, but wound up using it for another flight earlier this summer. I chose the Aerotech for availability, with similar specs, but hadn't considered the red flame. It was spectacular, but drowned out the clusters. When they flew, the only reason we know they lit was the long burn. I think a CTI classic would have had better effect but there it is.

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Taking it to the flight line, we had problems loading it onto the rail guide. While trying to get the parts to mate, we'd forced the forward rail buttons out of alignment. A smack of a rubber mallet later, we were ready for flight. This is definitely a Plan B rocket.

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Thanks to MaxQ, you've seen the video. It was an impressive flight to watch!

The clustering was mostly successful. 3 out of 4 burned, but as I mentioned they were hard to spot due to the bright red flame of the main motor. I'm not sure what happened with the fourth motor. The igniter was still in place, and hadn't fired at all. I had redundant timers so it shouldn't have been a problem. As I mentioned earlier, the switch on my continuity checker was damaged so I wasn't able to check that before flight. I haven't traced the wiring yet for reasons you'll see in the next post.

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Despite the uneven thrust, there was no noticeable problem with a flight that was nice and straight. The main popped at apogee and it slowly drifted into the middle of the field for an easy recovery.
 
It didn't land upright, but it was a nice gentle landing :)

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I even got to take home some fertile soil!

There was some damage. One part that didn't surprise me was the clustering electronics. This stuck up way too high to give me access to the switches, and I fully expected the shock cords to catch on it and destroy it. I fully expected a redesign before any following flights.

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The corrugation at the top of the S-IB stage was also damaged. This was just self adhesive paper and is easily replaced. I had thought about putting a thin fiberglass layer over that, and I think that ultimately would be a wise idea.

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The most serious problem though was a zippering of the inner blue tube. That I hadn't expected. That stuff is strong! Especially with the deployment of the main at apogee this was a surprise. It may also be the one problem that keeps it from flying again without major repairs.

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Another piece that was damaged happened before flight. It toppled off of a high table and one of the printed plastic pieces snapped. It was an easy fix but in the process the small section of body tube got punctured. Yes, I'm that much of a klutz. Again an easy fix except that in anticipation of my move I gave all of my unused body tubes and parts to a friend in Washington DC. So no fix in time for flight. Le sigh.
 
Where there is a will, there is a way.
Sounds like you had to improvise some, but way to go!
Failure IS NOT an Option.

Having to leave the states w/o getting this bird in the air would've been a bummer...
Curious about the air start set up ...so when you have time.....
 
The most serious problem though was a zippering of the inner blue tube. That I hadn't expected. That stuff is strong! Especially with the deployment of the main at apogee this was a surprise. It may also be the one problem that keeps it from flying again without major repairs.
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Zippering around the top of the blue tube ...looks minor but wow, I wouldn't have thought that would happen, esp. with a lower speed apogee deployment.
Can you tell us where the anchor point for the main shock cord is...down in the length of the core tube it appears...I've been pondering where/how to make strong anchor points inside the shell/airframe...was thinking of not putting it way down inside a body tube where I can't reach it and check for corrosion....thinking of making it anchor in the open like a traditional zipperless fin can.
Appears the damage is mostly repairable/cosmetic.
 
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So, for lessons learned...

One is the fiberglass. This was my first ever home made tube. I did not use enough layers and it was flimsier than I expected. I hadn't realised that fiberglass could dent! I had to fix one section with some epoxy clay. I was happy with my CF sections though and they had a stiffness I expected. I still needed the fiberglass though for the RF transparency.

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For some sections, such as the transition, I would use a mandrel and make a mold. Next time.

The 3D printed details worked well, but the big issue I have with them is CA glue. I wasn't happy with any of my joints. They were brittle and broke off easily. I don't know if using the 3D prints to create molds and then resin parts would have worked better. Comments?

The inner compartments for the electronics worked exactly as designed. The altimeters worked fine. I had been hoping to create some standard wiring pieces using molex connectors but was having problems getting the pins to fit in the connectors. I still hope to get this solved as it would allow me to use my electronics interchangeably and move them from rocket to rocket with a minimum of effort. So back to a dedicated wiring harness.

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The clustering electronics were a great idea, but as always the devil is in the details. A broken switch may have made the difference between the 3 motors firing and all 4 firing.

The big issue I have of mating the two sections could have been prevented with a different assembly technique. When I put the 3 inch blue tube into the 5.5, I could have done it with the couple in place to ensure it aligned properly.

So will it fly again? Probably, but not for a few years. I won't have physical access to it for a while but I definitely want to get this right. I may rebuild the upper section with a stronger FG tube and proper assembly to fix the alignment issues. I have a few years to consider options :D

I've definitely learned a lot with this build. Maybe I'll build an SA-5 Saturn I while I'm in Australia...
 
Where there is a will, there is a way.
Sounds like you had to improvise some, but way to go!
Failure IS NOT an Option.

Having to leave the states w/o getting this bird in the air would've been a bummer...
Curious about the air start set up ...so when you have time.....

A few more posts since this one... let me know if there's anything specific you want to know.
 
Zippering around the top of the blue tube ...looks minor but wow, I wouldn't have thought that would happen, esp. with a lower speed apogee deployment.
Can you tell us where the anchor point for the main shock cord is...down in the length of the core tube it appears...I've been pondering where/how to make strong anchor points inside the shell/airframe...was thinking of not putting it way down inside a body tube where I can't reach it and check for corrosion....thinking of making it anchor in the open like a traditional zipperless fin can.
Appears the damage is mostly reparable/cosmetic.

Sadly it's not cosmetic. It's structural. Remember that this is essentially a structure within a facade. This is the mating point between the upper and lower sections. This would require removal down to at least the centering ring, but that leaves the section short about two inches. If I rebuild the upper section, as I'm considering, that won't be a problem but it would certainly be a challenging fix as it is. There's just too little tube to work with.

My anchor point was the eye bolt attached to the motor. Any other solution would risk entangling either the upper or lower stuffer tubes. If I trim back to the centering ring zippering at this end shouldn't be a problem. I could always glass the other end.
 
My anchor point was the eye bolt attached to the motor. Any other solution would risk entangling either the upper or lower stuffer tubes. If I trim back to the centering ring zippering at this end shouldn't be a problem. I could always glass the other end.

Ok..so I got that....the zippered end of the core blue tube is where the forward section with the transition plugs into the lower section.


Anchoring to an eyebolt on the motor...that has been a very effective way to do it.
Most of my projects use the motor ejection well/end closure on the case as a last dich back up when the longer delay allows it...it has saved a rocket or two when a battery or electronics in the recovery subsystem failed.
But moving to L3 in my case will eventually require I go full redundancy with electronic recovery - so I'll probably try an eyebolt on the end of a motor case soon enough.
Some of the larger/length rockets I've done I've not particularly liked reaching down inside a long body tube for cleaning maintenance of the shock cord anchor point...and corrosion does mess them up over time.
I was stuck trying to figure out where to put that load bearing anchor point because there isn't much room inside where the mating points of the airfame come together...but your way may be the way to go.
 
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Ok..so I got that....the zippered end of the core blue tube is where the forward section with the transition plugs into the lower section.


Anchoring to an eyebolt on the motor...that has been a very effective way to do it.
Most of my projects use the motor ejection well/end closure on the case as a last dich back up when the longer delay allows it...it has saved a rocket or two when a battery or electronics in the recovery subsystem failed.
But moving to L3 in my case will eventually require I go full redundancy with electronic recovery - so I'll probably try an eyebolt on the end of a motor case soon enough.
Some of the larger/length rockets I've done I've not particularly liked reaching down inside a long body tube for cleaning maintenance of the shock cord anchor point...and corrosion does mess them up over time.
I was stuck trying to figure out where to put that load bearing anchor point because there isn't much room inside where the mating points of the airfame come together...but your way may be the way to go.

For the 75mm motors, there is no ejection charge. Accessing the anchor bolt is easy... just remove the motor and attach/detach the shock cord.
 
For the 75mm motors, there is no ejection charge. Accessing the anchor bolt is easy... just remove the motor and attach/detach the shock cord.

Too bad I did my design with a 54mm core motor.
The internal spacers looked a bit fragile when I drew up the fin can cross section with a 75mm core motor.
But I probably can get a eyebolt end closure for a 54mm. case.
I think Loki had them for even smaller motor cases.
 
Dave,
Your Saturn 1b is a magnificent build....amazing that she flew so stable with on of the smaller motors not firing. The video is just spectacular. Brings tears to the eyes to see the damage..but if anyone can repair it, it would be you. Also wanted to wish you good luck with your upcoming move!

Rick
 
This mirrors my experience in my hobbies, that no matter how much thought or planning goes into a project, nothing ever works as it should and a 5 minute job will take 2 hours, the less time I have, the longer it will take....

Glad it flew so well!

Frank
 
I know you're all itching to see progress on this build, as am I, so here's a personal status update.

As you may know my plan was to move to Australia. I had the job lined up, all I needed was the visa, and the new employer was sponsoring me. Well, apparently I'm too old to emigrate, so no work visa. Le sigh. I'm still working contract with them for a little while based here in Thailand, but it looks like I'll be back in North America soon. My wedding is in late September, so it may not be until after that, or it may be soon.

Work is continuing where I can. I'm already thinking about how to address the structural issues. I've plans for relocating the clustering electronics, and I've redesigned the cluster controller board. I'll get the PCB made before I return so all I have to do is add electronics. It'll be good to build again.

In the meantime, I've started a YouTube video series to document this and other projects I have on the go. I'll have several hours of video just catching up and explaining how I got to this point.

https://www.youtube.com/channel/UC4xGgMHU40BHQAXmDcR9IuA
 
Hello all!

I've been quiet lately as I don't have a place to work at the moment, but that doesn't mean I've been idle. I've added a lot to my YouTube channel about this build, so please check that out.

I've also fixed an old problem with my 3D model of the Apollo capsule. The details weren't fused properly, which meant many of the features had a hole behind them where they met with the capsule. Sadly, this meant they fell off with very little encouragement. With the beta FreeCAD software released in a more or less final state, it was time to revisit this. I had one detail that had to be fixed and I was able to fuse the whole thing. The fixed models are in the repository.

Of course, if you just want to download the models, I made it simple. They're now on Thingiverse! I'll do the same thing with the other detail parts over the next few weeks

https://www.thingiverse.com/thing:3184394

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Dave - enjoyed the instructional YouTube videos - well done! (and thanks for the props).
Waiting to see more ideas on your Phase Two renovation, so I can (steal) borrow them :)
 
Well, the phase 2 reno is ready to get started any time... all I need is some space to work. That may be a while. I hope to have it ready for the Apollo 50th, but we'll see.

In the meantime, how's your build going? I'd love to see yours fly too!
 
Well, the phase 2 reno is ready to get started any time... all I need is some space to work. That may be a while. I hope to have it ready for the Apollo 50th, but we'll see.
In the meantime, how's your build going? I'd love to see yours fly too!

Well, thanks for asking. Not much to report on the build itself.
After several months of intense design/build output on mine...two things:
I got a bit scarce on funding the next round of composite materials for the internal structure (as they say, "no bucks - no Buck Rodgers"), and I needed to reevaluate the electronics for the cluster/airstarts, and of course my other hobbies drew off some of my attention spare time and energy.(I have a couple of RC projects underway, try to stay active out at the local club field)
I noticed on several flights of other rockets during this build I was not getting 100 % success on the cluster/airstarts...so I began a side project as a test bed to see if I needed to reinvest in better electronics for this Saturn 1B. That side project is a modular cluster/airstart and/or two stage rocket made from all the left over parts I have in inventory...something I can do either cluster/airstarts on first motion or two stage ignition on burn out,...or both...economically.

The Saturn 1B is stacked in my walk in closet, begging for attention. I kind of wished I made it a team project now, but our club folks are spread out geographically and the local flyers in my neighborhood aren't as active, and the serious ones appear more focused on research/ex.

And of course it didn't hurt having you go first LOL.....:D

Your flight results indicate I might want to rethink a couple of things...……………...
 
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Well, thanks for asking. Not much to report on the build itself.
After several months of intense design/build output on mine...two things:
I got a bit scarce on funding the next round of composite materials for the internal structure (as they say, "no bucks - no Buck Rodgers"), and I needed to reevaluate the electronics for the cluster/airstarts, and of course my other hobbies drew off some of my attention spare time and energy.(I have a couple of RC projects underway, try to stay active at out local club field)
I noticed on several flights of other rockets during this build I was not getting 100 % success on the cluster/airs tarts...so I began a side project as a test bed to see if I needed to reinvest in better electronics for this Saturn 1B. That side project is a modular cluster/airstart and/or two stage rocket made from all the left over parts I have in inventory...something I can do either cluster/airstarts on first motion or two stage ignition on burn out,...or both...economically.

The Saturn 1B is stacked in my walk in closet, begging for attention. I kind of wished I made it a team project now, but our club folks are spread out geographically and the local flyers in my neighborhood aren't as active, and the serious ones appear more focused on research/ex.

And of course it didn't hurt having you go first LOL.....:D

Your flight results indicate I might want to rethink a couple of things...……………...

Yeah the air start was an interesting experience for me. It was my first ever attempt. I liked my first cluster controller idea, but had some implementation issues. I've already redesigned the PCB, but haven't had it manufactured yet. If it works out, I'll send you one since there are minimums to PC board orders and the parts are cheap. I need to mount it inside one of the SIB stage tanks instead of on top. That caused a lot of my problems. All this will be in a future video, but maybe I'll add a comment in here since the design stuff is already done. The nice thing about it is it can use redundant timers, and can check continuity on each of the igniters separately.
 
Yeah the air start was an interesting experience for me. It was my first ever attempt. I liked my first cluster controller idea, but had some implementation issues. I've already redesigned the PCB, but haven't had it manufactured yet. If it works out, I'll send you one since there are minimums to PC board orders and the parts are cheap. I need to mount it inside one of the SIB stage tanks instead of on top. That caused a lot of my problems. All this will be in a future video, but maybe I'll add a comment in here since the design stuff is already done. The nice thing about it is it can use redundant timers, and can check continuity on each of the igniters separately.

Well that would be nice...since I'm not that much of an electronics guy...most of my electronics gear is old reliable (so I thought) stuff I've had for years now (since Level 1 DD and Level 2)...maybe a decade or two ...so that might help my build out.

Your airstart device was your own design?
 
Well that would be nice...since I'm not that much of an electronics guy...most of my electronics gear is old reliable (so I thought) stuff I've had for years now (since Level 1 DD and Level 2)...maybe a decade or two ...so that might help my build out.

Your airstart device was your own design?

Partially. I made a simple controller that would allow continuity checking and redundant timers. I used 2x PerfectFlite miniTimer 4 for the actual timers.


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The controller has a push button to check continuity on up to 4 circuits. Like with redundant recovery devices, a primary would fire at the desired time, with a redundant timer firing shortly after in case the primary didn't have the desired results.

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Controller on 1 side with battery

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Timers on the other side, with independent batteries.

This first version had many problems. It was my first PCB, and the software I was using didn't create correct hole sizes... so I used a bigger sledge hammer. I also forgot switches for the timers, so that was a field repair. The biggest problem was my placement. Standing up from the top of the lower airframe, it kept snagging the shock cord, and that's what caused the zippering.

So, a redesign. Next post...
 
Here's the schematic of the controller. This is basically unchanged.

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The two timers connect to the header on the left. They pass through diodes to ensure the current doesn't back up into the inactive timer. So when one fires, the other is unaffected.

To check continuity, the push button allows a small current to flow from a battery through an LED. This current is enough to light the LED, but not enough to power an ematch. Yes, I tested it first without the motors! I have provision for a watch battery on the PCB, or an external 9V battery (not both). You then connect your igniters to the outputs.

This will work with from 1 - 4 igniters, so you don't even need a cluster if you just want to add redundancy to an airstart.

I haven't ordered the new PCB yet both due to a lack of work space and a lack of funds. Soon I hope. Here's an image of the top of the controller. I wasn't able to figure out how to get an image of the bottom, which is where the resistors and diodes are. They're all surface mount.

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The design files aren't online yet. I'll do that soon.
 
Doing a little more work on the cluster controller, although I still don't have the PCB to work with. So I printed out a full size image instead!

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One of the luxuries of working on a rocket this size is that space and weight aren't much of a problem. This will fit in one of the tanks, so I have a 3 inch diameter and about 3 feet of length to work with.

The plan is to make a compartment using laser cut wood, with the 3D printed sled bolted in. I have a date with the local library's laser cutter later this month, so I'll show that when I get there. Today I did the CAD work for the 3D printed sled.

The sled has 2 parts. On the bottom, is the battery compartment. This will hold 2x9V batteries for the ignition timers. These will fit into the compartment using 2x 1/4" bolts. It's supported on all 4 sides so no need for zip ties.

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The electronics are bolted on top of this using the same bolts. This requires less length, is easier to print, and provides a cover for the batteries while still allowing access.

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And this time, I've included the switches!
 
Doing a little more work on the cluster controller, although I still don't have the PCB to work with. So I printed out a full size image instead!
I have been known to make a 1:1 print of a PCB like you have and then glue it to some thicker cardboard. Holes can even be cut and connectors glued in place (CA glue) to achieve a good mechanical facsimile of the final assembly. I usually pass this to the mechanical engineers so they know what I will be giving them and neither of us end up with surprises!

These days a 3D printer does a great job for that as well, if you have access to one.
 
I have been known to make a 1:1 print of a PCB like you have and then glue it to some thicker cardboard. Holes can even be cut and connectors glued in place (CA glue) to achieve a good mechanical facsimile of the final assembly. I usually pass this to the mechanical engineers so they know what I will be giving them and neither of us end up with surprises!

These days a 3D printer does a great job for that as well, if you have access to one.

I don't think I need that level of verification, but I may do it just for fun :)
 
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