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Minimum Diameter CF 2 stage build thread "Kobayashi Maru"

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ColumbiaNX01

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View attachment 304042View attachment 304043View attachment 304044View attachment 304045View attachment 304046View attachment 304047

This rocket is scratch. All Carbon Fiber except for the interstage coupler which is FW fiberglass, nose cone coupler is FW black fiberglass, and Nose cone is a black fiberglass VK cone. The fins are 1/8 carbon fiber plate.

Minimum Diameter booster and 54mm sustainer. Plans are for an Aerotech M1850 in Booster and Aerotech L1090 in Sustainer.

Electronics Booster: 2 Perfect flight StrataloggerCF with a BRB900 GPS.

Electronics Sustainer: RRC3 "Extreme" (Deployment charges and ignition of sustainer) and RRC2+(redudant deployment charges), Missile Works RTX GPS for sustainer

Plan is it have Co2 ejection charges for apogee of booster and Black Powder charges for Main.

Plan is to have Co2 ejection charges for apogee of Sustainer and Black Powder charges for Main

I have also thought to use Co2 charges for everything. The benefit of that is not to deal with all the left over residue of the black powder. Leaning towards the Peregrine Co2 system. I also plan on using the Tinder Descender in the booster to wrap around the parachute so that I can have the main come out at altitude.
 
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amarillo_rocket

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Sounds like a fun project. I like the Peregrine Raptor C02 system. We ground tested it and it worked extremely well. Plenty of force to separate the drogue section. Odd sounding compared to the BP pop. Looking forward to seeing your progress.
 

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View attachment 304042View attachment 304043View attachment 304044View attachment 304045View attachment 304046View attachment 304047

This rocket is scratch. All Carbon Fiber except for the interstage coupler which is FW fiberglass, nose cone coupler is FW black fiberglass, and Nose cone is a black fiberglass VK cone. The fins are 1/8 carbon fiber plate.

Minimum Diameter booster and 54mm sustainer. Plans are for an Aerotech M1850 in Booster and Aerotech L1090 in Sustainer.

Electronics Booster: 2 Perfect flight StrataloggerCF with a BRB900 GPS.

Electronics Sustainer: RRC3 "Extreme" (Deployment charges and ignition of sustainer) and RRC2+(redudant deployment charges), Missile Works RTX GPS for sustainer

Plan is it have Co2 ejection charges for apogee of booster and Black Powder charges for Main.

Plan is to have Co2 ejection charges for apogee of Sustainer and Black Powder charges for Main

I have also thought to use Co2 charges for everything. The benefit of that is not to deal with all the left over residue of the black powder. Leaning towards the Peregrine Co2 system. I also plan on using the Tinder Descender in the booster to wrap around the parachute so that I can have the main come out at altitude.
Let me know if you want to borrow my peregrine set for testing. I have 8g, 12g, and the new fancy double barrel. Great product, great service.

Made nosecone or bought?
 

ColumbiaNX01

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Let me know if you want to borrow my peregrine set for testing. I have 8g, 12g, and the new fancy double barrel. Great product, great service.

Made nosecone or bought?
Its a FW commercial VK nose cone.
 

ColumbiaNX01

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Sounds like a fun project. I like the Peregrine Raptor C02 system. We ground tested it and it worked extremely well. Plenty of force to separate the drogue section. Odd sounding compared to the BP pop. Looking forward to seeing your progress.
How user friendly are they? Can they work in a tight spot? Is the entire assembly in avbay or mounted outside on the bulkplate?
 

ColumbiaNX01

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I took the payload section of the sustainer and compared it to my payload bay of my mongoose 75. The mongoose is black fiberglass. The difference is astonishing. The Carbon fiber is lighter but I did not know that much lighter. I am very happy!! I think I have saved anywhere between 3-5 pounds overall by going with carbon fiber over fiberglass.
 

BDB

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Did you start with a CF Mongoose 54? The trapezoidal fins look familiar. If so, I'd like to subscribe again. My Mongoose is next in line after my L2, and I'd love to eventually 2-stage it.
 

bill2654

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I'm subscribed. This threads going to take a while I think. My man Andrew here is going to be a proud papa in just 4 more days! Congrats buddy!:cheers:
 

ColumbiaNX01

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Did you start with a CF Mongoose 54? The trapezoidal fins look familiar. If so, I'd like to subscribe again. My Mongoose is next in line after my L2, and I'd love to eventually 2-stage it.
No, its a 3 inch anyway. No I just like the traditional design. Tried and True.

I thought about using my mongoose 75 as the booster but those fins are smaller. I wanted bigger fins on the booster and slightly smaller on the sustainer. This was there is more drag for when it separates after booster burn out. I believe it is better stability with a bigger fin span and root.
 

ColumbiaNX01

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I'm subscribed. This threads going to take a while I think. My man Andrew here is going to be a proud papa in just 4 more days! Congrats buddy!:cheers:
Thanks buddy. I will do my best to influence my little guy to be a Aggie and another Rocket Man!
 

ColumbiaNX01

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I weighed everything out and all parts weighed only 8.25 pounds. Of course that is not including motors, recovery, electronics, and epoxy. But still incredible light.

I figured the weight of the motors and have added it up. With the rocket itself plus the M1850 and L1090 the weight is 26.9 pounds. That does not include epoxy, recovery, or electronics. The electronics are only a matter of grams and really wont make a whole lot of difference. Then there comes the epoxy. If I use the special loctite Hysol epoxy then I probably wont have to do Tip-to-tip. So epoxy weight will be alot lower then if I did tip to tip, but that is still up in the air.

I am mostly likely looking at under 30 pounds fully loaded on the pad.
 
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dhbarr

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How user friendly are they? Can they work in a tight spot? Is the entire assembly in avbay or mounted outside on the bulkplate?
They're very user friendly, a lot like building a reloadable motor in fact. They are roughly the size of an 8g or 12g co2 cart, the specs for which I don't have handy.

You could mount them however you choose, but in one direction excessive G's could conceivably cause a premature event via spring compression. Mitigation techniques are one of the things I'd want to test. My side-by-side dual assembly fits in a 54mm tube.
 

ColumbiaNX01

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They're very user friendly, a lot like building a reloadable motor in fact. They are roughly the size of an 8g or 12g co2 cart, the specs for which I don't have handy.

You could mount them however you choose, but in one direction excessive G's could conceivably cause a premature event via spring compression. Mitigation techniques are one of the things I'd want to test. My side-by-side dual assembly fits in a 54mm tube.
How does it compare to the rouse tech one sold by apogee?
 

blackjack2564

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Nice project ya got there. Good luck Andrew!

FYI: My fins on my 75mm minimum were just Hysol'd on.
 

ColumbiaNX01

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Nice project ya got there. Good luck Andrew!

FYI: My fins on my 75mm minimum were just Hysol'd on.
That's what I am contemplating. I like tip to tip but it adds weight but by using the correct epoxy tip to tip is not required. How many tubes of hysol did you go through after tacking on fins and fillets?
 

dhbarr

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How does it compare to the rouse tech one sold by apogee?
The rigid mounting bracket was a desirable feature for me. I anticipate the CD3 would be a lot lighter, but it appears like it might break earlier. You can view also mount the CD3 a bunch of different ways.

I will probably buy one of them some time in the next year or two to compare directly.
 

blackjack2564

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How many tubes of hysol did you go through after tacking on fins and fillets?
My fins are 3/16th's carbon uni-plate. I have 4 fins also.....used approximately 3 sets of Hysol. Didn't use the needle twist mixing tips, just pumped into cups and mixed by hand. [those darn tip sets are expensive & single use]
I used a 1.5 in PVC pipe section to pull fillets, probably overkill size wise. Charlie used 1 in. section PVC on his.

DSCN5951.jpg

So depending on your fillet size you may use much less. [you have 3 fins vs my 4]
There was some blush on mine, which came off easily with windex and dried with denatured alcohol. High humidity in North Carolina.
 

ColumbiaNX01

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My fins are 3/16th's carbon uni-plate. I have 4 fins also.....used approximately 3 sets of Hysol. Didn't use the needle twist mixing tips, just pumped into cups and mixed by hand. [those darn tip sets are expensive & single use]
I used a 1.5 in PVC pipe section to pull fillets, probably overkill size wise. Charlie used 1 in. section PVC on his.

View attachment 304139

So depending on your fillet size you may use much less. [you have 3 fins vs my 4]
There was some blush on mine, which came off easily with windex and dried with denatured alcohol. High humidity in North Carolina.
Thanks Jim. Did you us the small 50ml/1.69oz tube of hysol?
 

ksaves2

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Have you tested or know if your trackers behave well from within your confines? If the GPS receiver is deaf to the incoming signals could be a problem there. If the 900Mhz signal can't get out of the airframe that's a different issue and can
be remedied by having an antenna for the 900 Mhz signal on a bulkhead that is exposed at apogee separation. At least the downside can be tracked for recovery and what is recorded from the upside (if any since you'll be going very fast) can be downloaded from your trackers onboard memories when you get them back.

I see you have listed fiberglass couplers and nosecone. A fellow did post a 1db attenuation of a 70cm tracker which could be a problem for a project that is going to be flying at the extremes in a black non-CF nosecone. I believe something like carbon based lampblack is used as a colorant which can attenuate RF. Yes, attenuation can be frequency and power dependent. I had that when I checked the memory of a 70cm Beeline after nothing was heard during a simple 10k flight. The .kml file had 6 to 11 satellite lock most of the time except on boost. GPS signals received fine but Rf couldn't get out. (It was an FG project with metallic paint. The paint was the issue.)

If the Missileworks product is being used in the sustainer, am I correct to assume it will be riding in the ebay? If so, it will be encased by CF until apogee. I would make sure your GPS can receive the satellites from within your bays first before applying epoxy. If you find you have a problem, get as wide as you can get away with fiberglass switchband to act as a window for the incoming satellite signals.

It would be easy to mock this up with couplers, bulkheads and masking tape. Put the trackers in the proposed bays, just tape the bulkheads on and take them outside and see if you get a fix on them in a short period of time. You might consider a
range test out in the open and see how far the signal will carry. I've been burned by an inadequate range test and lucked out when the maiden flight returned within sight. You won't have that luxury with your project if the first flight is
going to be with your intended motors. One could argue for a shakedown flight at lower impulse depending on your comfort with your tracking arrangement. Best of luck. Kurt Savegnago
 

ColumbiaNX01

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Have you tested or know if your trackers behave well from within your confines? If the GPS receiver is deaf to the incoming signals could be a problem there. If the 900Mhz signal can't get out of the airframe that's a different issue and can
be remedied by having an antenna for the 900 Mhz signal on a bulkhead that is exposed at apogee separation. At least the downside can be tracked for recovery and what is recorded from the upside (if any since you'll be going very fast) can be downloaded from your trackers onboard memories when you get them back.

I see you have listed fiberglass couplers and nosecone. A fellow did post a 1db attenuation of a 70cm tracker which could be a problem for a project that is going to be flying at the extremes in a black non-CF nosecone. I believe something like carbon based lampblack is used as a colorant which can attenuate RF. Yes, attenuation can be frequency and power dependent. I had that when I checked the memory of a 70cm Beeline after nothing was heard during a simple 10k flight. The .kml file had 6 to 11 satellite lock most of the time except on boost. GPS signals received fine but Rf couldn't get out. (It was an FG project with metallic paint. The paint was the issue.)

If the Missileworks product is being used in the sustainer, am I correct to assume it will be riding in the ebay? If so, it will be encased by CF until apogee. I would make sure your GPS can receive the satellites from within your bays first before applying epoxy. If you find you have a problem, get as wide as you can get away with fiberglass switchband to act as a window for the incoming satellite signals.

It would be easy to mock this up with couplers, bulkheads and masking tape. Put the trackers in the proposed bays, just tape the bulkheads on and take them outside and see if you get a fix on them in a short period of time. You might consider a
range test out in the open and see how far the signal will carry. I've been burned by an inadequate range test and lucked out when the maiden flight returned within sight. You won't have that luxury with your project if the first flight is
going to be with your intended motors. One could argue for a shakedown flight at lower impulse depending on your comfort with your tracking arrangement. Best of luck. Kurt Savegnago
Everyone knows the gps signals cannot go through carbon fiber. The gps is going in nose cone. The nose cone coupler is fiberglass and the nose cone itself is fiberglass as well. While the gps rests in the confines of the coupler there will be a hole that is in the bulk plate that the RTX 8 inch antenna will slide through. The nose cone is 15 inches long. The antenna will be in the middle of the nose cone while the gps transmitter is in the coupler. This way the signal can reach the transmitters antenna.

The BRB900 will be going into the booster's interstage couple which is fiberglass. Yes the CF airframe and CF switch band will be over that. While the rocket is on the pad and under boost the GPS signal will not be going through the carbon fiber. Once it has staged and the interstage coupler visible the BRB900 should regain a lock with the receiver. Since the booster will go over 15,000 feet I need a tracker in it. I do not see any other way around that.

If you have any ideas much would be appreciated.

thanks
 
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Zebedee

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What's your plan for preventing ignition of the 2nd stage if it's not pointing up at the right time?
 

ColumbiaNX01

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What's your plan for preventing ignition of the 2nd stage if it's not pointing up at the right time?
The Missile Works RRC3 has a minimum altitude check in its Aux port where e-match is at. If it does get to at least a certain altitude it will not fire motor. I have not decided what altitude. I thinking between 3,000 and 4,000. That gets it up there a ways. My estimation if it does not get that high it is because it is way off course and if so the sustainer will not light.
 

ksaves2

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Everyone knows the gps signals cannot go through carbon fiber. The gps is going in nose cone. The nose cone coupler is fiberglass and the nose cone itself is fiberglass as well. While the gps rests in the confines of the coupler there will be a hole that is in the bulk plate that the RTX 8 inch antenna will slide through. The nose cone is 15 inches long. The antenna will be in the middle of the nose cone while the gps transmitter is in the coupler. This way the signal can reach the transmitters antenna.

The BRB900 will be going into the booster's interstage couple which is fiberglass. Yes the CF airframe and CF switch band will be over that. While the rocket is on the pad and under boost the GPS signal will not be going through the carbon fiber. Once it has staged and the interstage coupler visible the BRB900 should regain a lock with the receiver. Since the booster will go over 15,000 feet I need a tracker in it. I do not see any other way around that.

If you have any ideas much would be appreciated.

thanks
Ok, The BRB is 250mW output so you shouldn't have issues with Rf getting out of the booster. I have the other Ham Beeline GPS procducts and there is a
"keep-alive" button cell on the board that supplies power to the GPS memory. What this does is, if reception is lost of the satellites it keeps the ephemeris table
alive for a time. When reception returns, the time to achieve lock is greatly shortened. Since the BRB900 is one of Greg's products, I bet there is a button cell on the board. When the time comes, make sure you put a fresh one in.

How can you tell aside from the battery if you can get a quick lock? Take your unit out after it has been off for a week or so and see how long it takes to get a lock.
Shut it off and turn it on, see how long it reacquires the signal. It follows before you launch, make sure the BRB900 has a good satellite lock before you button up the bay and I heard folks who do this stuff regularly to launch as soon as you can so it doesn't take too long to get another lock on the booster after separation.

Again, you can ground test this very easily so you can be certain it will work in flight.

As far as the black FG nosecone, as mentioned there might be some attenuation even though it is not CF. I've seen posted 1db for 70cm. The Missileworks product
is also 250mW so you should be ok there. Again, ground test the heck out of everything.

As far as "everyone knows this or that". When I started out 9 years ago with a ham license I didn't find any of this information "out there". Now it is if one
cares to search. Makes it a lot easier to avoid what are now simple mistakes. Take shortcuts and the risk of being burned is greatly enhanced.

One other test you might consider is set your completed project up on a pad at home sans motors, wire up contained ematches and your second stage igniter circuit.
Turn everything on including the trackers and let is sit for an hour. Yup, I've been burned with Rf dorking deployment electronics. Deployment on the pad is most embarrassing and in your case, ignition of the sustainer with people around the pad could be very messy. Also had an apogee deployment on ascent that could only have been from an RDF tracker ripping the deployment altimeter. The flight was subsonic "and" the Mach lockout was set for a few seconds as a safety precaution. You have an interesting endeavor planned and I hope
you have a very rewarding flight. Kurt Savegnago
 

ColumbiaNX01

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Ok, The BRB is 250mW output so you shouldn't have issues with Rf getting out of the booster. I have the other Ham Beeline GPS procducts and there is a
"keep-alive" button cell on the board that supplies power to the GPS memory. What this does is, if reception is lost of the satellites it keeps the ephemeris table
alive for a time. When reception returns, the time to achieve lock is greatly shortened. Since the BRB900 is one of Greg's products, I bet there is a button cell on the board. When the time comes, make sure you put a fresh one in.

How can you tell aside from the battery if you can get a quick lock? Take your unit out after it has been off for a week or so and see how long it takes to get a lock.
Shut it off and turn it on, see how long it reacquires the signal. It follows before you launch, make sure the BRB900 has a good satellite lock before you button up the bay and I heard folks who do this stuff regularly to launch as soon as you can so it doesn't take too long to get another lock on the booster after separation.

Again, you can ground test this very easily so you can be certain it will work in flight.

As far as the black FG nosecone, as mentioned there might be some attenuation even though it is not CF. I've seen posted 1db for 70cm. The Missileworks product
is also 250mW so you should be ok there. Again, ground test the heck out of everything.

As far as "everyone knows this or that". When I started out 9 years ago with a ham license I didn't find any of this information "out there". Now it is if one
cares to search. Makes it a lot easier to avoid what are now simple mistakes. Take shortcuts and the risk of being burned is greatly enhanced.

One other test you might consider is set your completed project up on a pad at home sans motors, wire up contained ematches and your second stage igniter circuit.
Turn everything on including the trackers and let is sit for an hour. Yup, I've been burned with Rf dorking deployment electronics. Deployment on the pad is most embarrassing and in your case, ignition of the sustainer with people around the pad could be very messy. Also had an apogee deployment on ascent that could only have been from an RDF tracker ripping the deployment altimeter. The flight was subsonic "and" the Mach lockout was set for a few seconds as a safety precaution. You have an interesting endeavor planned and I hope
you have a very rewarding flight. Kurt Savegnago
What do you mean RF dorking deployment electronics? The altimeters are barometric pressure altimeters. How can a "signal" interfere with that? I have heard that sometime before but never had a issue? Can it work in the reverse? Can a barometric pressure altimeter interfere with the signal of the GPS?
 

dhbarr

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What do you mean RF dorking deployment electronics? The altimeters are barometric pressure altimeters. How can a "signal" interfere with that? I have heard that sometime before but never had a issue? Can it work in the reverse? Can a barometric pressure altimeter interfere with the signal of the GPS?
It's the transmitter on some electronics that doesn't play well with others. Newer electronics are less susceptible to this outside interference, but it's worth ground testing anyway.
 
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