Three Quarters of a Hundred Grand with Sunday Silent (75k' Balls Project)

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Really amazing thread! Not that you need my encouragement, very dedicated doesn't come close to describing your drive and determination. But we are watching this thread closely! Good luck on this , can't wait to see it together
 
We're actually getting there. I can see it now.

prophecy

Looks like you're making great progress Steve. The glue will have time to cure in the trailer.

I already have your pad mounted on the truck. Driving it around just to make sure the weight of everything won't be a problem. Kind of a low priority thing, but everything else is packed, charged, aligned, yada, yada, yada ...you know me!

Unless things change, you'll have until at least 9AM Sunday, so get a little rest, man.

See you soon.

Jim

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Thanks Nick & Jim.

Sleep count since last update: 90 minutes

I got very unlucky last night and got stuck at the office until 8. As I sat on the phone listening to various folks try and get their egos in alignment for hours on end, I could feel my energy window slipping away pretty rapidly. All we need to do when we get home is laminate a fincan for a flight that sims to Mach 4, no big deal...

A jog (as opposed to a walk) to the parking garage, a Sonic stop, and a Walmart stop for a Mountain Dew got me a little more energized, and I went home to get going.

First step was to transition the shop to a format conducive to laying up. As I was doing this, I spoke with Jim on the phone for some input on specific issues I had when bagging the Verrukt fincan. I was going to attempt to troubleshoot myself, but the thing about vac bagging is that success or failure in troubleshooting isn't revealed until the epoxy is curing and the vac is pulling air, and at that point it's usually too late to do anything but a hack-fix. So, when I realized the guy driving my project to the playa is one of the hobby authorities on vac bagging and composite work, I figured a phone call wouldn't be such a bad idea. Thanks, Jim, for your time - very helpful.

Anyway, we're off the phone at 10 and already almost through our first Mountain Dew (just to CYA this time, I bought 3).

The only guest I'll allow in my apartment during a build session is this guy - he's a mood-lifter and isn't distracting (when you've been in hibernation mode for the better part of a month, this is what becomes of you. Buyer beware)

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My least favorite part of laying up fincans is the seemingly endless prep work (which is actually 80% of "laying up the fincan.") But you gotta start somewhere - so in this case, let's measure out our templates on 33 cent Walmart poster board (33 cents!):

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Cutting thick, loose-weave carbon when you haven't slept in a week will leave you cussing like a sailor:

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But after a second Mountain Dew, we get through it:

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Fincan prepped for surface prepping (prep to prep):

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This isn't the first project where the guillotine jig is seemingly tremendously useful for everything except what it's meant for. All prepped for layups:

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The larger setup...my apartment is starting to feel really, really small. It's now 1am and no epoxy has been mixed, and you best believe getting the sealant tape pressed down on the edge against the kitchen counter with no room to work was a beetch:

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At 1:30am we're mixing epoxy. In the past, I've taken a fold-over approach to bagging; a problem I've had since I've done my last few cans alone is that it's very hard to not get any creases/poor seal areas without a second set of hands to help fold over the bag. So after putting on all the layups, I changed my approach and decided to just oversize the bag and lay another piece of film on top of the original piece that I was going to fold over. It took 40 minutes to seal all four edges, and the epoxy was starting to cure, but finally at 2:16am, we pull a vacuum, and our delirium seems to have been worthwhile. A rewarding moment for sure when it squeezes:

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One small problem - the pump was LOUD. Like, really loud. I try not to use my mixing vac pump for vac bagging where it's left on for hours on end, so I borrowed one that I'd never used before, and holy crap was it loud. Really can't have neighbors coming to ask me to turn it off for a multitude of reasons, principal among them that my likely response would be "avoiding a shred is way more important than the remaining 3 hours of sleep, you're probably one of the neighbors that has a dog that barks all the time." But, in all seriousness, I was dreading being asked to turn it off when it was under such good compression after so many hours to get it that way. So with my eyes half shut, I came up with this solution:

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Anybody that knows me knows I'm an OCD neat freak; I'm always making sure things are tidy and aligned at launches, making sure my stuff is packed and in the right place, making sure my towers are at 90 degrees EXACTLY...the one exception to this is when I'm working on something. I make an absolute mess when I'm working towards completing something. I made such a mess (little carbon bits were EVERYWHERE) that after going under vac at 2:16 I was cleaning till 4:30.

At this point, I chugged an EmergenC, and then sat down on the blanket next to the vac pump and was so tired I passed out right there, even though the vac pump was louder than sharing a hotel room with Manny (and that's saying something).

My smoke alarm woke me up 90 minutes later, thanks to the oil vapors. So, we swung into action before any pissed off neighbors came knocking and knocked out the battery and turned off the pump. Luckily, the epoxy was rock hard, so we're good. When I woke up, here's what I saw:

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As I was doing this, my alarm went off. Time to get up! Opened a window and left for work. Another day!

This was the last big construction step; but I've been down this road too many times to view this as a sort of victory. The dreaded "putting it all together" part looms, and though I was exhausted by Tuesday of this week, I'm six feet under levels of dead. I've tried to make sure I thought through every part fitting, every potential design "gotcha," etc., as I went along, but final assembly with a new (especially custom-sized, machined, etc.) rocket always reveals at least eight things you didn't think of. Last year's nightmare was the o-ring glands being too shallow, which resulted in two consecutive all nighters and being 10 hours late to drop things off with Jim, for which I'm still apologetic.

So close, yet so far. Ablative, motor assembly, and av bay to go; t-less than 24 hours.

Coffee, EmergenC, Mountain Dew, rinse repeat. "Now is the time to re-define the grind"

prophecy
 
This has to be up there for best/ most inspiring / most dedicated threads ever!

I'm really enjoying following this, thanks for keeping it updated!

Nate
 
This is easily one of the most inspiring threads I have ever read. I skimmed over this thread while pulling an all-nighter for school and it motivated me to get through. :)
 
I passed out right there, even though the vac pump was louder than sharing a hotel room with Manny (and that's saying something).


Damn.

My roommate did say the worst part about our trip to Japan was the snoring, apparently even worse than being packed into a train like sardines for 6 hours....
 
Well, the rocket hit the road for Black Rock at 6am this morning. My hands look like they were run through a blender and contracted arthritis all in the same weekend, and it's 9:54am and I'm on my third cup of coffee. I've come this far with this thread, so I'm going to see it through. Here goes.

Friday

I went home from work, still delirious from Thursday's all-nighter vac bagging the fincan. Jim had told me that if I needed to, I could meet him Saturday evening or even at the crack of dawn Sunday morning with the stuff; I was going to try and get it done on Friday night just to get it out of my hair and have some semblance of a normal weekend. Laughable, indeed.

I got home and completely hit a wall. The only thing I absolutely had to do on Friday night was apply the ablative to give it time to cure, so I pulled the can from the bag and removed the peel ply. Good compression, good saturation, no wrinkles, mission accomplished. There was some cotton batting that overlapped the peel ply a bit and got stuck, but the few cotton fibers I wasn't able to pull off will be covered by ablative anyway, so no need to bother with sanding.

Mix up a massive batch of ablative (consistency of spackling putty) and spread it on as evenly as possible, because this stuff is NOT easy to sand:

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Put my phone on airplane mode and passed out at 9pm - I remember a time just a few short years ago when I wouldn't have been able to live with myself for wasting a Friday night, but this may have been the most beautiful thing I've ever seen. Woke up 8am Saturday feeling like a new person.

Saturday

Ah, the dreaded "putting it all together" time. Sure, it always takes longer than you think, but each year I temper expectations based on the previous year's gross underestimation, and still, somehow, I'm always off. I think this stems from the fact that rockets are generally built in sections; fincan, motor, etc. "Finishing" each section really means it's about 95% done; final drilling/sanding/gluing/fitting is always left to be done at the end. When you multiply this 5% of outstanding work to be performed over 10 parts of the rocket, that's a bitch of a step and it's all happening at once. "Foreseen unforeseen problems" seems to be the best way to describe it. The solution to almost all of these is an even mixture of 45% elbow grease, 45% hours on hours, and 10% ingenuity. Even if we assume that I'm an endless source of elbow grease - which, not having slept in three weeks, is an extremely dubious notion, but I've got no choice but to be - the hours are going to start to run out on us here. All we can do is get going.

I received the worst good news (or the best bad news) on Saturday morning; Jim was unhappy with the upper level wind forecasts for his flight, and was debating not making the trip. Whatever he decided, it gave me valuable extra time as he delayed his departure by a day to wait for more proximate forecasts. If this hadn't happened, I'd have been **** out of luck. So I put it out of my mind and started tackling the problems, one by one, going as fast as I can and no faster:

Problem 1

I need a forward insulating disk for the head end of my motor and an av bay bulkplate. In both instances, an accurate fit is very important. I don't have any kind of drill press or anything with which to fabricate one of these. I bought a circle cutter jig for my Dremel, only to realize that the cutting bit wouldn't touch the G10. I had to muscle it through, and the result was a very sloppy cut. So I rough cut two blanks with a jig saw and got them as close to circular as possible. My plan had been to get them "close enough" on my disk sander and then concentricize them by chucking them on a hand drill and holding sandpaper around them, but my friend Ryan had a pretty neat idea that I was able to execute on. Set up a rotary station on the disk sander table. Three hours and a bleeding finger later, we're in business:

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But it made a mess, of course. So, we pause for an hour to clean up this bad boy:

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Problem 1 solved. Problem 2 is the looming sanding of the ablative, but it's now about noon on Saturday and it's not yet hard enough to sand. So I put it in the shotgun seat of my car and left it in a parking lot to bake. Sometimes (sometimes) it's nice living in Texas.

While I waited for this to cure, I decided to work on my av bay. This is the one part of this project that really worked out unexpectedly; I had been worried about the challenges of an off-spec nosecone with a strong enough coupling mechanism and still somehow fitting all the electronics in the RF transparent part of it. Part 1 to the solution of this problem was done a few weeks ago with the coupler, now it's time to build a slick removable bit to keep the electronics in the tip of the nosecone and save us the mass of an allthread, because we already gave up some mass savings to the thick FWFG material (free) and the thick Aluminum coupler (no choice).

Bada bing:

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The sled will weigh 1lb or so with everything on it and the flight maxes out at right around 50g. Six x #8 x 1/4" stainless screw tips will absolutely hold a max dynamic load of 50lbs, and we've saved the weight of the allthread.
 
At this point, I had to go to Lowe's to get BBQ paint for my nosecone (since we're skipping the ablative there) before they closed. While I was there, I bought a 25 pack of 80 grit sandpaper for my power sander in preparation for the dreaded ablative step.

When I got home, in the fading daylight I spray painted the nosecone with the BBQ paint on the railroad tracks behind my building. Choices with BBQ paint are always black, white, and silver - I never use black because it gets very hot in the sun and that's no good with electronics; I've historically used white, but it gets really dirty and ends up looking horrible. So, even though I didn't want to look like I was trying to make the rocket look all-aluminum (since I'm proud of the composite parts!) we've got no choice:

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Then, it was time to go to war with the ablative. It was 7:30 on Saturday night; my rocket was supposed to be loaded on the trailer by now, and I had a front row seat at a Houston Astros game that was left empty (well, I think my girlfriend invited one of her friends). Anyway, I felt terrible, but destroying my hands, my apartment, contracting black lung and sanding 75g of ablative off my fincan just sounded like too much fun. I told myself I would call it quits at 9:30 regardless of where it was; as it turned out, it took about an hour per side to get it looking really good, so I went till 11:30.

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Final weight of 3.02 pounds. For the concessions we made to use off the shelf parts (including that God awful warped G10...) and to expedite the build process (very thick carbon, heavy fillets in lieu of more layers of layup), giving up just over a pound as compared to the highly optimized fincan my friends made in the same size is an outcome I'm pretty happy with. The ablative turned out awesome; in addition to hopefully serving its purpose and ablating, it acted as an awesome filler and sealer for the thick carbon step/weave.

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We had a little BBQ paint left over, so back to the railroad tracks because why the hell not:

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At this point, I opened a beer, turned on some Southern rap and spent two hours on my hands and knees for the second time today cleaning the mountains of pink dust from every corner of my apartment. Got to bed at 3:30
 
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Yesterday morning, up at 8am again, but not feeling quite as chipper as we had been on Saturday morning. All we've got to do today is put the motor together and pack!

First step is to knock out the nozzle pin ring from when we pinned it in as we milled the holes. A tool is required. I tried to buy a pin punch from Lowes, but they only sell them in packs, so I bought a $1.94 5/32" drill bit from Wal Mart and Dremeled off the fluted part. Bam, pin removal tool.

An hour later:

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Before we load the motor, my BBQ paint was dry on my fins and nosecone, so I couldn't resist the opportunity for a dry fit. First we weighed our nosecone. 2.66 pounds; for a gloriously inefficient nosecone that I'm using because it was free, I cut off most of it and came up with the best solution I could with a coupler that was strong enough and an av bay that was still RF transparent. I'll take it.

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Then we put the fincan on. 3.755" dia fincan, 3.750" dia tube. Should be a perfect fit.

Not even close. Don't know which part was out of round, but I avoided post curing for this reason, and was crushed to discover this. It's the oldest "gotcha" in the book, and the last one I have time for today. With 8-hour old scabs, it's time for chapter three of going to war sanding the fincan. I have a flapper wheel I use for prepping casting tubes when mixing motors, but it's 150 grit and not very good for material removal. So, 60 grit by hand smoothed over with the 150 grit flapper wheel, 3 hours, somehow figuring out how to remove the fincan after test fits by myself in a classic 2-person job, and a lot of cursing from continually scraping the bleeding spots over the edges of the fincan tube as I was sanding, and we have a goosebumps moment:

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It's now noon. Jim called and confirmed that he would be leaving at 5am Monday morning. He lives 3 hours away, so in order to not keep him up, I'd have to leave at 7. Time to wrestle with this motor.
 
Since R45 needs time to cure and grain bonding on this motor is of particular importance, we need to do this first. Flapper wheel comes back to haunt us to prep the inside of the liner; we sand each of the grains and line them up in order:

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Mix up 300g of R45 and glue away. Thank goodness for drop cloths:

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Originally, I had planned to put a G10 "washer" aft of the nozzle grain to help support the nozzle grain under G loading; upon subsequent conversation with some friends, it was decided that this was more of a risk than a benefit, but I had factored 1/8" of extra liner space in to my motor design with this in mind. The last thing I want is unexposed liner and a potential hotspot, so I put a bead of RTV along the liner ID at that spot.

While this cures happily, it's time to wrestle with the case. I need to de-burr and chamfer the inside of the pin holes somehow without compromising my sealing surface, and then grease the whole ID of the case because my design mandates that everything slide in from one end and I don't want to roll an o-ring. Had to get pretty creative with how to do this on a 6 foot length of pipe, but I figured it out:

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I took a crack at deburring and chamfering with 600 grit sandpaper:

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The edges of the pin holes were still a little sharp, but I wasn't sure how to better do it - I didn't want to run sandpaper inside the hole and potentially enlarge the pin holes. So we load up the holes with grease and take a whack at it:

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It went in perfectly, but inspection of the pin holes revealed barely perceptible to the naked eye pieces of silicone; functionally it would probably be fine, but I haven't come this far to bet on it. At this point, it's 7pm, and I'm once again late for Jim, with grease everywhere, running on the fumes of fumes, with no idea what to do. Eff.

I took half an hour to knock the closure out (everything is more difficult with a 6 foot tube when you're by yourself) and clean the grease to try again. I found an old countersink bit and twisted it by hand in each of the holes and sanded again; much better this time! Funny how the clutchest solutions seem to come under pressure. New o-rings (I started buying lots of extra; learned that lesson the hard way before) and the closure zips right in. No shaving. AWESOME. Time to pack up:
 
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The last step of packing up was to slide the closure all the way up the case; my lightweight closure design is only an inch thick, so it'll be very easily cocked and jammed, so I wanted to do this with the aid of gravity and the propellant stack to keep it square. Hard to do with 9 foot ceilings, so I tried to get the closure going by hand to give the propellant stack enough room to comfortably couple into before pushing. Again, very challenging with one person, and the closure promptly got stuck. It didn't appear to be cocked and there's no way it rolled an o-ring, so I have no idea what it is, but at this point it's 8pm on Sunday night. I need to leave. I've had time to troubleshoot and solve all but one of the "gotchas" the weekend threw at me, drawing the elbow grease and ingenuity parts of the equation from God knows where. But I've run out of hours. Manny and I are going to have to tackle this next Friday at Balls; it'll be much, much easier with two people and a rested brain (and rested arms).

I wrapped the liner/grains in a moving blanket, packed up the case, grabbed a Mountain Dew from the fridge, and headed to Austin.

Luckily, Jim is a Packers fan, so he had told me he was staying up for the game. I found the game on the radio, and pulled in to Jim's driveway just as the 2 minute warning occurred. No harm, no foul.

Left Jim's at 11:45 and headed to In-n-Out for the second annual celebratory "I can't believe I did it and it's out of my hands" meal. In n Out was pretty quiet at 12:15 on a Monday morning, but no less delicious:

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Bought another two Mountan Dews and hit the road at 12:30; got home at 3am. My 6:40 alarm came early this morning, and I'm a zombie at work chugging EmergenC not to get sick - but today is the last day of that.

So this is what it feels like to give yourself wholly to something, document every step of the way, and truly refuse to take no for an answer when life is trying to shove that conclusion down your throat at more than one juncture.

Gluttonous, irresponsible, selfish are some words that come to mind, but I'm my own harshest critic - but, nobody can ever take it away from me, and this one's been all me. Hopefully I have a 70k'+ flight to show for it in 5 short days.

My coach used to say "be better than your excuses and you won't have any." Probably the thing that irks me the most about people, especially my fellow millennials, is flakiness. I don't care how entitled my generation is, if you say you're going to do something, do it. If you say you're going to be somewhere, be there. If you commit to something, be it a rocket project, a build thread, or a trip to the grocery store, see it through, regardless of the degree to which it inconveniences you. When Manny and I had to get weighed to ride the Verruckt waterslide back over the 4th of July, I was 187 pounds. I'm now a much scrawnier 171 as a direct result of trying to practice what I preach and giving up all things necessary to see my commitment through. I'm starting to look like Christian Bale in the Machinist (great movie, by the way.)

I was talking to my friend yesterday, who was originally going in 50/50 with me on this project and is now in the Air Force. I told him I didn't know where my rocket journey would take me next; I can't progress from this project on my own financial means without a partner, and probably shouldn't ever duplicate this level of spending again. At some point, I need to grow up and not stretch myself so thin. I think this is as far as I can (not at all) feasibly go on my own until I'm retired and have more time and money (in 40 years...)

We'll see how long he's enlisted. For now, I'm going to limp through the work day and get some sleep and maybe reconnect with some of the people I haven't seen in a month-plus.

See you guys next Friday in Gerlach.

Steve Heller
 
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Well Steve, I've read some of your other threads and I have to say, when you go all in you really go all in. I'm looking forward to the launch report. Your threads inspired my 54mm build for Aeronaut. I'm sorry that I didn't get to meet you when we were there.

I'm right in the middle of the range where I don't have the time (stay at home wife + 2 kiddos) or the money(stay at home wife + 2 kiddos) for projects like this. Sometimes I miss the days where I could spend an entire month's salary on a hobby project and then eat mac n cheese every day until the next pay day and not feel guilty about it. I never had the endurance to go without a decent night's sleep for more than 24 hours though. Enjoy it while you can.
 
Wait-what are the motor specs?

21kNs O3800

3.75"x3.5" case (standard 98mm "snap ring style" liner) with 56" propellant length.

Current simulation puts the rocket at 71k' and right around Mach 4.
 
Well done, Steve! Thank you so much for documenting the process! I admire your resolve in pursuit of success; let nothing stand in your way!

Once again, congrats, rest well for a few days, then go kick some tail at Black Rock!!!!

Oh, and Manny, have a great time as well!!!!

-Eric-
 
Good stuff man. One thing occurred to me reading your Friday night thoughts. When you are young a wasted Friday night is the worst. When you get older, a wasted Friday night is the best. Keep up the good work and good luck on the flight.
 
Thanks all.

Chris - thanks, I think we met briefly when I was making igniters for Mark H/Clay's rockets flying out of your tower, but regardless, I look forward to talking more at a launch in the near future. Yeah, I'm with ya on the guilt/time constraints thing - go back about 18 months, my life looked a lot different and I was staring down a very large purchase of a different kind. But if it wasn't evident in this thread, I'm kinda cut from a different cloth, and I eventually had to accept that I wasn't ready to trade this stuff in for board games, picnics, walking the dog, and eventually, the more serious responsibility you mention. When the time comes, I'll know it.

Grouch - well said! Funny, many of my best Fridays of the former type were on that college campus in Middletown. I had a friend from high school that went there, so I made some trips when I was home from NC for most of my first two years. Great place, I really wanted to go there myself but either wasn't smart enough or hipster enough, one of the two. Still the only place in the world I've discovered the delicacy that is Popov, $8 for a good night.

Wilson - shouldn't you be mixing?
 
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Well Steve, I've read some of your other threads and I have to say, when you go all in you really go all in. I'm looking forward to the launch report. Your threads inspired my 54mm build for Aeronaut. I'm sorry that I didn't get to meet you when we were there.

I'm right in the middle of the range where I don't have the time (stay at home wife + 2 kiddos) or the money(stay at home wife + 2 kiddos) for projects like this. Sometimes I miss the days where I could spend an entire month's salary on a hobby project and then eat mac n cheese every day until the next pay day and not feel guilty about it. I never had the endurance to go without a decent night's sleep for more than 24 hours though. Enjoy it while you can.

It is possible to build large rockets when you have a job, a wife and three kids - it just requires a lot more planning.
 
Steve's rocket is in Fernley - WooHoo!

I am there too with some other rockets. We will have fun now.

Jim
 
Good deal Jim, thanks for the update and glad you got in safely.

I just checked in for my flight, got boarding spot #119 somehow despite booking as soon as I got out of a meeting during which the flight became eligible for check in. Sardine can to San Diego, has a ring to it.

Anyhow, I'll plan to call you from SD - let's tie out on plans for Fri AM. Figure you'll be on the playa setting up when I leave here.

/s
 
Currently enjoying a beer at DSM then I'll be en route to BALLS. Should arrive to Bruno's at 8am tomorrow morning. Tomorrow will be a work day then we'll light this motor first thing Saturday morning.
 
I decided I couldn't miss this either. Leaving SLC at lunch tomorrow Catch you guys sometime around 8pm id guess. Any rooms left at Brunos? Let me know if you need any last minute supplies
 
I decided I couldn't miss this either. Leaving SLC at lunch tomorrow Catch you guys sometime around 8pm id guess. Any rooms left at Brunos? Let me know if you need any last minute supplies

Hey Ryan,

Awesome news, really glad you're gonna be able to join us!

I just landed in San Diego, and will connect up to Reno shortly. I had planned on sleeping in my rental car as Bruno's is famously booked a year in advance, but was in the right place at the right time and scored a cancelation room, which is a minor win for comfort and a massive win for functionality in having an indoor place to prep (I had been planning on using a friend's room during the day tomorrow while he was out on the playa).

Manny has volunteered to be my prep partner tomorrow, which I've warned him will involve spending most of the day at Bruno's. I've sunk so much money and heart into this thing that I don't want to take my eye off the prize a day early and prep distracted on the playa.

My plan is as follows:

I'll arrive at Bruno's around midnight and get my key from Jim. Manny isn't slated to arrive in Gerlach until around 9:30am, so I'll head out with Jim Jarvis around 4:30am to get his project up first thing, then head back into town to intercept Manny and get to work.

We will absolutely be working at 8pm and would love to meet up with you when you arrive - Laraway has my number, give me a call.

-steve
 
prophecy-just curious, but how will the G10 fins hold up against the mach 4 stresses?
 
prophecy-just curious, but how will the G10 fins hold up against the mach 4 stresses?

The BBQ paint in shockwave prone areas will get cooked off and ablative on the fins will be "stressed". I suspect the leading edges will show the effects of heating quite pointedly. If they stay on the airframe, will be an impressive accomplishment.

Robert DeHate has sent some staged rockets to pretty high speeds. Look here for some pics: https://www.dehate.com/index.php/galleries/rockets/balls/2006#!100_0300

Scroll through and look at the leading edges of the fins of the upper stage.

He has a photo somewhere of a rocket that spent 24 seconds or so above Mach 2 and the leading edges of the fins were pretty cooked and eroded into the laminate piles.
Going to Mach 4 is really going to be something. Best of luck Kurt:headbang:
 
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