I have to agree ,another one of your fine builds !!
I love those glamour shots ,and I like that launch pad.
What`s next JR ? I look forward to another of your builds.
Take care
Paul T
I like building stuff
I have to agree ,another one of your fine builds !!
I love those glamour shots ,and I like that launch pad.
What`s next JR ? I look forward to another of your builds.
Take care
Paul T
ROCKETRY DELINQUENT ,I put my soul in what I do.
I built a rocket, and on the seventh day ,I rested
Level 3
CAR 1033
Manitoba Rocketry Group
CTI a better way to fly !
BAR jack of all trades
Thanks Paul. I appreciate it!Originally Posted by sodmeister
Oh, I dunno... I'll probably go back to work on my BT-80 Saturn V and Saturn I-F... those have been on the back burner for awhile. Got some more kits I've picked up at HL and other places on closeout that I need to finish, as well as my TLP Maverick missile... (does Sandman make decals for that one??) Been toying with some scratchbuilt ideas (the RDC "ISV Venture Star" starship from James Cameron's "AVATAR" among them) and a kitbash (picked up an Estes "36DD squared" at HL on closeout, NO WAY am I making it into a "booby rocket"... been thinking about sorta trapezoidal fins and a pointy-er nosecone, painted like a "Nike-Ajax" but with the dual first stage motors... maybe call it "Nike-Hera" or "Nike-Athena" due to it's 36DD heritage and dual first stage motors...
Just some ideas I'm toying with... maybe Wes will have another beta-build for me to do sometime soon...
I'm open to suggestions...
Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
I like building stuff
You are pretty much in the same little boat as me.......too much going on ,and the boat is taking on water fast ! Time to get some stuff finished and jettison them before I sinkThanks Paul. I appreciate it!
Oh, I dunno... I'll probably go back to work on my BT-80 Saturn V and Saturn I-F... those have been on the back burner for awhile. Got some more kits I've picked up at HL and other places on closeout that I need to finish, as well as my TLP Maverick missile... (does Sandman make decals for that one??) Been toying with some scratchbuilt ideas (the RDC "ISV Venture Star" starship from James Cameron's "AVATAR" among them) and a kitbash (picked up an Estes "36DD squared" at HL on closeout, NO WAY am I making it into a "booby rocket"... been thinking about sorta trapezoidal fins and a pointy-er nosecone, painted like a "Nike-Ajax" but with the dual first stage motors... maybe call it "Nike-Hera" or "Nike-Athena" due to it's 36DD heritage and dual first stage motors...
Just some ideas I'm toying with... maybe Wes will have another beta-build for me to do sometime soon...
I'm open to suggestions...
Later! OL JR
Major problem being the lack of painting that can be done ,or rather ,cannot be done untill who knows.
Paul T
ROCKETRY DELINQUENT ,I put my soul in what I do.
I built a rocket, and on the seventh day ,I rested
Level 3
CAR 1033
Manitoba Rocketry Group
CTI a better way to fly !
Rookie
Looks good! I have learned alot from your build threads!
NAR #93724
Birds in the hangar:
Dr. Zooch Mercury Redstone
Dr Zooch Mark II
Estes Der Red Max
BAR jack of all trades
Thanks! Welcome aboard!!!
Lots of good stuff around here... feel free to ask questions!
Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
Lifetime Member
OK Luke...tomorrow is John Glenn's 50th anniversary of his flgiht...finished up Dr. Zooch's shuttle...with a lot of help from your build...going to start Zooch's Mercury Atlas next!!
BAR jack of all trades
Yep... and we got three inches of rain night before last... so much for flying it on the anniversary!
Maybe at the next club launch!
Good luck with your build! (feel free to add on any tips, tricks, or gotchas, or just general build observations here if you like! (and pics!) OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
Lifetime Member
sorry to hear about the rain....but I know you guys went through a spell with NO rain at all....I am looking over the instructions and this is going to be a fun build!! I have never built an Atlas...so this will be fun! Have you had a chance to fly your Mercury Atlas ? (or your Atlas Agena?) how do they fly?
Yep... and we got three inches of rain night before last... so much for flying it on the anniversary!
Maybe at the next club launch!
Good luck with your build! (feel free to add on any tips, tricks, or gotchas, or just general build observations here if you like! (and pics!) OL JR
Windblown Rocketeer
Very nice, very nice indeed!
NAR # 91455
BAR jack of all trades
Flew the Atlas Agena, but I don't think I got pics... like every other Zooch kit, it pretty much flies like it was on rails...
Wes really puts a lot of work into making sure his kits fly well as well as look good...
Haven't flown the Mecury Atlas yet... maybe at the upcoming club launch (if it's not too wet, and NO... I'm NOT complaining! Sorry for the club guys that have only had two launches in last YEAR here, but if we end up rained out for this next one *I* certainly won't be crying about it... besides we went and looked at our other farm at Shiner with the club guys here and from the San Antonio/Austin area about having joint launches up there on the Shiner farm since it's halfway between Houston and San Antonio (and Austin is a little closer) and I think March will be the inaugural launch for that...) Should be fun!
I expect the Merc Atlas will be a good flyer too... probably a little draggier than the Atlas-Agena, due to the tower and capsule versus the smooth nosecone of the Agena, but I expect they'll be pretty similar in all respects otherwise... and the BT-50 "Freedom 7" Mercury Redstone in the same "ant-scale" as the Mercury Atlas flies TERRIFIC, so I have high expectations...
They look neat together...
Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
BAR jack of all trades
Something Wes shared with me that you guys might enjoy...
http://www.aero-news.net/index.cfm?d...3-8ddc94308fb9
Very appropriate considering the 50th Anniversary!
Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
U.S. Manned Space Program
Nice Mercury-Atlas JR!Something Wes shared with me that you guys might enjoy...
http://www.aero-news.net/index.cfm?d...3-8ddc94308fb9
Very appropriate considering the 50th Anniversary!
Later! OL JR
The article that Wes wrote was a fine and fitting tribute.
Greg
Ant Member
Today I celebrated by speaking with a gang of 11 Girl Scout Brownies (my daughter is one of them). We talked about the Friendship 7 flight, they got to handle models, watched some short video and then we went on to talk about lunar exploration. Next we went out to the nearby ball fields and shot my Dr. Zooch Mercury Atlas Friendship 7 version. Then the kids shot a total of 16 other rockets (all SPEVs). The weather was some of the best I've seen- dead calm winds, clear blue skys and sweatshirt temp.s Rockets were going up on "C" engines and coming back on the pad. It was a grand day to remember a grand event in United States history!
In short- I was lucky and I got to fly my Friendship 7 Mercury Atlas on the 50th! YES!!!
Lifetime Member
agree with you there...every kit I have from him flies just great...even my Saturn 1b...now with 25 flights to her credit. The Atlas Agena is a neat looking rocket too...I am going to get that one as well....along with his Vostok, EFT-1, SLS......
Flew the Atlas Agena, but I don't think I got pics... like every other Zooch kit, it pretty much flies like it was on rails...
Wes really puts a lot of work into making sure his kits fly well as well as look good...
Haven't flown the Mecury Atlas yet... maybe at the upcoming club launch (if it's not too wet, and NO... I'm NOT complaining! Sorry for the club guys that have only had two launches in last YEAR here, but if we end up rained out for this next one *I* certainly won't be crying about it... besides we went and looked at our other farm at Shiner with the club guys here and from the San Antonio/Austin area about having joint launches up there on the Shiner farm since it's halfway between Houston and San Antonio (and Austin is a little closer) and I think March will be the inaugural launch for that...) Should be fun!
I expect the Merc Atlas will be a good flyer too... probably a little draggier than the Atlas-Agena, due to the tower and capsule versus the smooth nosecone of the Agena, but I expect they'll be pretty similar in all respects otherwise... and the BT-50 "Freedom 7" Mercury Redstone in the same "ant-scale" as the Mercury Atlas flies TERRIFIC, so I have high expectations...
They look neat together...
Later! OL JR
Lifetime Member
that was a great tribute to John Glenn's flight...really well done!!
Something Wes shared with me that you guys might enjoy...
http://www.aero-news.net/index.cfm?d...3-8ddc94308fb9
Very appropriate considering the 50th Anniversary!
Later! OL JR
Lifetime Member
sounds like an AWESOME day!!!
Wes...sounds like you had a great day with your daughter!!!! next thing you know your daughter will be a junior in college, a nursing student with a 3.94 gpa...and you wonder...what happened?? where did 21 years go?? (but she still comes along with her camera to try to take pictures of her old man and his rockets...
Today I celebrated by speaking with a gang of 11 Girl Scout Brownies (my daughter is one of them). We talked about the Friendship 7 flight, they got to handle models, watched some short video and then we went on to talk about lunar exploration. Next we went out to the nearby ball fields and shot my Dr. Zooch Mercury Atlas Friendship 7 version. Then the kids shot a total of 16 other rockets (all SPEVs). The weather was some of the best I've seen- dead calm winds, clear blue skys and sweatshirt temp.s Rockets were going up on "C" engines and coming back on the pad. It was a grand day to remember a grand event in United States history!
In short- I was lucky and I got to fly my Friendship 7 Mercury Atlas on the 50th! YES!!!
BAR jack of all trades
WAY cool!!!Today I celebrated by speaking with a gang of 11 Girl Scout Brownies (my daughter is one of them). We talked about the Friendship 7 flight, they got to handle models, watched some short video and then we went on to talk about lunar exploration. Next we went out to the nearby ball fields and shot my Dr. Zooch Mercury Atlas Friendship 7 version. Then the kids shot a total of 16 other rockets (all SPEVs). The weather was some of the best I've seen- dead calm winds, clear blue skys and sweatshirt temp.s Rockets were going up on "C" engines and coming back on the pad. It was a grand day to remember a grand event in United States history!
In short- I was lucky and I got to fly my Friendship 7 Mercury Atlas on the 50th! YES!!!
Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
BAR jack of all trades
Thanks! Hope to fly her at an upcoming launch soon! Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
Lifetime Member
dang silver paint! ARRRGH!! tried using Testors Chrome....sigh.... good paint and just a bad painter...it sagged. .... finished up the launch escape tower...sat it on my little work table here...and my one cat (ornery as all get out..completely black cat...looks like a Halloween decoration...also weighs in at 22 pounds...) chases our new cat...hits my work bench causing the capsule to fall off and break the tower...how is that for a night of model making?
rats!!
BAR jack of all trades
Ooooh...Sorry to hear that! I feel your pain...
IMHO the chrome paint is MUCH more trouble than it's worth... I tried it on the Atlas Agena and it was a NIGHTMARE!!! I managed to salvage it but the stuff was soft and sticky for about a week and the "mirror" effect was VERY shortlived...
Probably the best way to get a 'mirror' chrome finish with any kind of durability to it is to just use trim monokote... (the self-stick kind).
later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
Lifetime Member
Luke,
I agree with you 100% on the chrome....I went with Testors silver metallic and that was much more workable....the tower was an easy fix... that thing is actually kinda strong....the cat knocked that thing off the table and it basically broke the tooth pick ..err... I mean aero spike and loosened a strut...easy to fix and my Sigma 7 is back ready for flight...I managed to salvage the booster and with the new paint its acceptable.
I have never built an Atlas rocket before...and this thing kit is really cool!! I am working on my flame fins now...Dr. Zooch kits are a great way to make it through the winter duldrums....I have his Saturn 1 Block 2 for my next build...I am already eyeing his web site for my next buy...I am going to go for the Atlas Agena I think!!
Ooooh...
IMHO the chrome paint is MUCH more trouble than it's worth... I tried it on the Atlas Agena and it was a NIGHTMARE!!! I managed to salvage it but the stuff was soft and sticky for about a week and the "mirror" effect was VERY shortlived...
Probably the best way to get a 'mirror' chrome finish with any kind of durability to it is to just use trim monokote... (the self-stick kind).
later! OL JR
BAR jack of all trades
Yep, they definitely are neat kits!
I'm toying with the idea of an "upscale" Atlas Centaur using many of the same techniques, enlarged for a BT-80 tube... But it won't be anytime real soon because I have enough other irons in the fire right now...
The BT-80 is just about my favorite size of rocket... big but not TOO big...
Course, there's nothing wrong with the BT-60 either...
The tower looks delicate, but it's actually stronger than one might really think... sorta like the real thing... "strength from shape" and all that...
Later! OL JR
PS. One thing about the "Chrome"... the Atlas wasn't actually chome, it was stainless steel... so actually going with a paint that's a touch "darker" than say Chrome trim monokote, actually tends to make the model look BIGGER than it actually is...
Besides, fueled on the pad for liftoff, the whole upper 2/3 of the rocket was covered with white frost anyway... That's why I just used Valspar Silver on the bottom of my Friendship 7 and flat white for the upper tank...
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
BAR jack of all trades
Finally flew my Friendship 7 Mercury Atlas, a couple weeks or so after the actual 50th anniversary...
Here she is, loaded up with a C6-5 on Pad 14Z-- "Z" for Zooch...
Range is GO, all systems are GO... We are entering the final countdown...
Main engine ignition...
To be continued... OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
BAR jack of all trades
Cont'd...
"The clock has started"... We have LIFTOFF!!!
"GOD SPEED JOHN GLENN!!!!"
The boost was high and pretty straight, just a gentle arc toward the south, as winds were light from the south, a very smooth, high flight... Ejection looked about perfect, and on the way down, I noticed that the tower was actually upright, between the shroud lines... interesting. She came down smoothly and landed in boot deep clover maybe 100 yards from the pad...
I retrieved her and everything appeared to be in good order... until I noticed THIS...
This has to be THE worst case of "Estes dent" I've ever seen... the slit is actually where the transition snapped back into the top lip of the tube (which was TOTALLY unharmed, I might add-- not even a paint scratch!) and the tube cut into the transition nearly the depth of the shoulder!Then a large chunk of wood popped out never to be seen again... SO, she'll be in the shop awhile til I figure out exactly how to fix this... I'm presently trying Carpenter's Wood Filler, but I'm unsure how durable or desirable that's going to be... or how well it will "stick" in the hole, and how well it'll hold up being 1/4 inch thick or so... may have to do something different... and I'm open to suggestions...
Upon a little further investigation, I noticed a strange "half moon" cut in the very peak of the Zooch trash bag chute. Upon inspecting the top lip of the body tube, sure enough, there is a hair-thin line of yellow plastic embedded in the very top edge of the tube where, evidently, the parachute was pinched between the snapped-back nosecone and the top edge of the body tube... the tube evidently cut straight through the plastic chute like a razor blade and into the cone before everything popped apart and the chute deployed... interesting! I'm just glad she came down intact.
I think the thing is the shock cord is too short... especially with half it's length being kevlar leader coming out of the "teabag" shock cord mount, with the other half being elastic. I think I'm going to quit using the kevlar/elastic combo and just switch to straight elastic... or at least double or maybe triple the length of the elastic... What I think happened is, the ejection charge went "BOOM!" and the nosecone and chute blew off... the kevlar leader and shock cord played out to full length, which put the cone about a foot from the rocket or thereabouts, then it started to stretch. Since the kevlar does NOT stretch, it forces the elastic to stretch MUCH FARTHER than it would were it one long piece of elastic... IOW the elastic stretches twice as much along it's half length as it would if it were stretching along it's full length... in both cases it would stretch equal amounts, just the half length elastic stretches twice as far over that half length than the all-elastic cord would stretching over it's FULL length (since it'd be twice as long). The more you stretch elastic (the higher the 'percentage' of stretch for a given length) the more energy it stores, and the harder it snaps back... (at least that's been my experience... do a test-- stretch a piece of elastic that's a foot long 6 inches-- it'll nearly be as far as it can stretch-- say near 100% of it's stretch capability. Now let it go... POW! it snaps back HARD! Now stretch a 2 foot long piece of elastic 6 inches... it can actually stretch MUCH farther because it's longer, so each inch of the elastic is actually stretching less since the same distance/energy is spread out over more inches of elastic... so for argument we'll say it stretches 50% of it's total "maxed out" stretch limit... now let it go... it snaps back, but with MUCH less force... 3 feet is even better... a 6 inch stretch on 36 inches of elastic is hardly stretching it at all, and when let go it rather lazily flops back with MUCH less force. That's what I think is happening here. Since I already have the kevlar leader glued in, I'm gonna add about 2 feet or so of elastic to the existing elastic shock cord before I fly her again... that should give more room to dissipate ejection energy (both on the way out and on the way back from any 'snapback' and give the chute more time to open and get things tumbling or slowing down to dissipate any snapback energy, which should itself be less severe due to the longer cord spreading it out more...
Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
Cardstocker
Bad news, thanks for sharing the issue, i'll do a double check in my nosecone before launch.Cont'd...
"The clock has started"... We have LIFTOFF!!!
"GOD SPEED JOHN GLENN!!!!"
The boost was high and pretty straight, just a gentle arc toward the south, as winds were light from the south, a very smooth, high flight... Ejection looked about perfect, and on the way down, I noticed that the tower was actually upright, between the shroud lines... interesting. She came down smoothly and landed in boot deep clover maybe 100 yards from the pad...
I retrieved her and everything appeared to be in good order... until I noticed THIS...
This has to be THE worst case of "Estes dent" I've ever seen... the slit is actually where the transition snapped back into the top lip of the tube (which was TOTALLY unharmed, I might add-- not even a paint scratch!) and the tube cut into the transition nearly the depth of the shoulder!
Upon a little further investigation, I noticed a strange "half moon" cut in the very peak of the Zooch trash bag chute. Upon inspecting the top lip of the body tube, sure enough, there is a hair-thin line of yellow plastic embedded in the very top edge of the tube where, evidently, the parachute was pinched between the snapped-back nosecone and the top edge of the body tube... the tube evidently cut straight through the plastic chute like a razor blade and into the cone before everything popped apart and the chute deployed... interesting! I'm just glad she came down intact.
I think the thing is the shock cord is too short... especially with half it's length being kevlar leader coming out of the "teabag" shock cord mount, with the other half being elastic. I think I'm going to quit using the kevlar/elastic combo and just switch to straight elastic... or at least double or maybe triple the length of the elastic... What I think happened is, the ejection charge went "BOOM!" and the nosecone and chute blew off... the kevlar leader and shock cord played out to full length, which put the cone about a foot from the rocket or thereabouts, then it started to stretch. Since the kevlar does NOT stretch, it forces the elastic to stretch MUCH FARTHER than it would were it one long piece of elastic... IOW the elastic stretches twice as much along it's half length as it would if it were stretching along it's full length... in both cases it would stretch equal amounts, just the half length elastic stretches twice as far over that half length than the all-elastic cord would stretching over it's FULL length (since it'd be twice as long). The more you stretch elastic (the higher the 'percentage' of stretch for a given length) the more energy it stores, and the harder it snaps back... (at least that's been my experience... do a test-- stretch a piece of elastic that's a foot long 6 inches-- it'll nearly be as far as it can stretch-- say near 100% of it's stretch capability. Now let it go... POW! it snaps back HARD! Now stretch a 2 foot long piece of elastic 6 inches... it can actually stretch MUCH farther because it's longer, so each inch of the elastic is actually stretching less since the same distance/energy is spread out over more inches of elastic... so for argument we'll say it stretches 50% of it's total "maxed out" stretch limit... now let it go... it snaps back, but with MUCH less force... 3 feet is even better... a 6 inch stretch on 36 inches of elastic is hardly stretching it at all, and when let go it rather lazily flops back with MUCH less force. That's what I think is happening here. Since I already have the kevlar leader glued in, I'm gonna add about 2 feet or so of elastic to the existing elastic shock cord before I fly her again... that should give more room to dissipate ejection energy (both on the way out and on the way back from any 'snapback' and give the chute more time to open and get things tumbling or slowing down to dissipate any snapback energy, which should itself be less severe due to the longer cord spreading it out more...
Later! OL JR
Sorry about that, you build was great!
Ant Member
Actually, I had a very similar damage on my own during testing- but mine was blown off at ejection.
I cannot send you a replacement part for a while- I'm totally out of that component until my BMS order comes in, but as soon as it does I'll get a new adapter off to you.
Member
Without repl the whole cone....I'm presently trying Carpenter's Wood Filler, but I'm unsure how durable or desirable that's going to be... or how well it will "stick" in the hole, and how well it'll hold up being 1/4 inch thick or so... may have to do something different... and I'm open to suggestions...
...
Later! OL JR
I'd take an exacto knife/file, trim the chip area into an easier to dupe shape, then shape a repl chunk to glue in there.
Little sanding painting and never see it again; and not enuff weight to throw out of balance..
Is that supposed to smoke like that?
BAR jack of all trades
Thanks Wes... In the meantime I'm going to try to repair the one I have... After all the spacecraft adapter is glued to the top of it... if I can't salvage it I'll have to cut the spacecraft off and remove all the wood from inside the BT-50 tube to use it on the new transition...
This one is a pretty clear cut case that it's snapback... thing is I hardened this transition with CA... considerably... I soaked CA into the outer layer of wood and then ALSO into the end grain. While it reduces dinging of the surface, it's also perfectly clear it doesn't do much to harden the core wood itself. The thing I'm most concerned with is to ensure that it doesn't happen AGAIN... that's where I think the longer shock cord comes in... that's what I'm going to try anyway.
Of course a certain amount of it is probably just stupendous bad luck... bad luck that they hit in just that way to bust the cone. OF course the counterpoint is also true... it's actually some pretty good luck that the damage was no worse-- no damage to the rocket body tube AT ALL, even the paint! The other thing is that the tower, capsule, even the spacecraft adapter are perfectly intact, AND even though the transition was damaged pretty badly, the damage was on the 'back side' out of view, and it didn't wipe out the details on the surface of the transition, so it's actually probably about as good as the situation could be under the circumstances...
Later! OL JR
The X-87B Cruise Basselope- THE ultimate weapon in the arsenal of homeland defense and only $52 million per round!
Lifetime Member
Luke!! that is terrible!!! I finished up my Mercury Atlas and it is really a cool rocket.
Maybe Wes can clarify...but I thought I read somewhere in a prior post that the balsa adapter for the Mercury Atlas is the same part as his adaptor for his Saturn 1b? I think you said previously you have all of his Saturns...maybe you can raid one of your 1b's for the adaptor until a new one arrives? If that is incorrect I apologize...but I thought I read that on an old post. I just took down my Atlas and my Zooch Saturn 1b...Luke...they sure look the same to me....
Cont'd...
"The clock has started"... We have LIFTOFF!!!
"GOD SPEED JOHN GLENN!!!!"
The boost was high and pretty straight, just a gentle arc toward the south, as winds were light from the south, a very smooth, high flight... Ejection looked about perfect, and on the way down, I noticed that the tower was actually upright, between the shroud lines... interesting. She came down smoothly and landed in boot deep clover maybe 100 yards from the pad...
I retrieved her and everything appeared to be in good order... until I noticed THIS...
This has to be THE worst case of "Estes dent" I've ever seen... the slit is actually where the transition snapped back into the top lip of the tube (which was TOTALLY unharmed, I might add-- not even a paint scratch!) and the tube cut into the transition nearly the depth of the shoulder!
Upon a little further investigation, I noticed a strange "half moon" cut in the very peak of the Zooch trash bag chute. Upon inspecting the top lip of the body tube, sure enough, there is a hair-thin line of yellow plastic embedded in the very top edge of the tube where, evidently, the parachute was pinched between the snapped-back nosecone and the top edge of the body tube... the tube evidently cut straight through the plastic chute like a razor blade and into the cone before everything popped apart and the chute deployed... interesting! I'm just glad she came down intact.
I think the thing is the shock cord is too short... especially with half it's length being kevlar leader coming out of the "teabag" shock cord mount, with the other half being elastic. I think I'm going to quit using the kevlar/elastic combo and just switch to straight elastic... or at least double or maybe triple the length of the elastic... What I think happened is, the ejection charge went "BOOM!" and the nosecone and chute blew off... the kevlar leader and shock cord played out to full length, which put the cone about a foot from the rocket or thereabouts, then it started to stretch. Since the kevlar does NOT stretch, it forces the elastic to stretch MUCH FARTHER than it would were it one long piece of elastic... IOW the elastic stretches twice as much along it's half length as it would if it were stretching along it's full length... in both cases it would stretch equal amounts, just the half length elastic stretches twice as far over that half length than the all-elastic cord would stretching over it's FULL length (since it'd be twice as long). The more you stretch elastic (the higher the 'percentage' of stretch for a given length) the more energy it stores, and the harder it snaps back... (at least that's been my experience... do a test-- stretch a piece of elastic that's a foot long 6 inches-- it'll nearly be as far as it can stretch-- say near 100% of it's stretch capability. Now let it go... POW! it snaps back HARD! Now stretch a 2 foot long piece of elastic 6 inches... it can actually stretch MUCH farther because it's longer, so each inch of the elastic is actually stretching less since the same distance/energy is spread out over more inches of elastic... so for argument we'll say it stretches 50% of it's total "maxed out" stretch limit... now let it go... it snaps back, but with MUCH less force... 3 feet is even better... a 6 inch stretch on 36 inches of elastic is hardly stretching it at all, and when let go it rather lazily flops back with MUCH less force. That's what I think is happening here. Since I already have the kevlar leader glued in, I'm gonna add about 2 feet or so of elastic to the existing elastic shock cord before I fly her again... that should give more room to dissipate ejection energy (both on the way out and on the way back from any 'snapback' and give the chute more time to open and get things tumbling or slowing down to dissipate any snapback energy, which should itself be less severe due to the longer cord spreading it out more...
Later! OL JR
Lifetime Member
Luke...speaking of Dr. Zooch Saturns....I am building his Saturn 1 Block II now.....this is going to be another cool kit. To me, the Block II was one of those rockets that I was aware of...but I really always focused on the 1b, which is my all time favorite...now that I am building it...this is a neat rocket. I am going to go with the SA5 next...which is sitting here looking at me.
Posting Permissions
Reply With Quote
