Cert 1 and 2: Jolly Logic Challenge

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FlyBy01

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https://www.rocketryforum.com/threads/4-loc-goblin.148895/

some more.. you can compare your build with this one..


or this one:
https://www.rocketryforum.com/threads/loc-goblin-thread.145083/

Enjoy the build! enjoy the flights! (I miss mine!)
I have read all of these and all are cool in that there is no right or wrong as long as it is safe. The video of the goblin coming in ballistic make me cringe at the loss and it’s very cool at the same time because it was documented.
 

o1d_dude

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View attachment 408927
I used these instead so I didn’t have to worry about the prongs.
These are what I use. They properly called “brad hole” t-nuts. Madcow uses these in their paper rocket kits.

The t-nuts with prongs can be made to work by hammering the prongs flat. Only downside is the flange is a bit thicker than the brad hole type.

Both types may require bending a curve into the flange to fit the body tube properly. Depends on the tube size.

Lowe’s usually keeps these items in the flat drawers in the fastener aisle. Very reasonably priced and useful.
 

Speaknoevil

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The prong versions are cheaper. Again, I just turn them over. Don't like metal sticking out of the airframe.
 

FlyBy01

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Had this paint hanging around so might as well use it on the motor adapters just to see if it makes any difference. Also tapped for fillets and started the nose cone work.
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Wallace

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For those of you who are tired of Loc Goblins runaway now (dad joke of the day).
Since I'm not a millionaire and neither are my parents I am building what I think is the most cost effective rocket for both certifications.

Now John Beans the creator of the Jolly Logic Chute Release asked for the community to post all attempts for certification using his creation. So this thread is has started.

Goal 1: Build Loc Goblin
Goal 2: Fly Cert 1 on 29mm H182R
Goal 3: Study for Cert 2 test
Goal 4: Fly the Cert 2 using my 54mm gear
Goal 5: The journey to Certification 3
Is this "challenge" subsidized and or rewarded in any way? If so I congratulate. If not, it makes little sense. You'd be much better served with rockets optimized for each flight. Unless of course it is a personal challenge.
 

FlyBy01

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Is this "challenge" subsidized and or rewarded in any way? If so I congratulate. If not, it makes little sense. You'd be much better served with rockets optimized for each flight. Unless of course it is a personal challenge.
No one has provided any financial support and this is of my own accord. Post 1 says it all; it is a cost effective method to work toward cert 1 and 2. Also I have the 54mm hardware already and primarily plan to fly on that.
 

grouch

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Honestly it’s a solid plan. L2 means a lot of different things to different people. I wanted my L2 at the time because I was primarily interested in clusters. Some want to do it with a rocket that will see mostly H’s, some want a big heavy and complex thing on L’s. The Goblin will eat J’s all day long but still fly on H’s.
 

Wallace

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No one has provided any financial support and this is of my own accord. Post 1 says it all; it is a cost effective method to work toward cert 1 and 2. Also I have the 54mm hardware already and primarily plan to fly on that.
Outstanding! You've taken it upon yourself then, without reward. Although I suspect some may well be coming your way.
 

Wallace

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I admit to having rockets that I thought would be well enough suited for differing levels so I am not here to judge. Chute release is a fantastic/easy way to avoid wiring/programming/packaging issues and I do actually own one. But....There's always a but..You could have built two optimized rockets utilizing "true" dual deployment for roughly the same coin and learned much more along the way.
Twenty bucks for a Quark and an hours worth of your assembly time would have easily saved you enough dough to build a truly capable second rocket. Just throwing ideas at Ya, again, not criticizing your choice.
 

FlyBy01

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I have a new love, hate with fin fillets. Love how they look; hate how much work they take. All I can say is follow the Rocket Poxy directions on waiting 30 minutes to allow for the epoxy to thicken. All I really have left is filling spirals and everyones favorite past time.... sanding.

Don't be to harsh, first time I have done fin fillets on a High Power Rocket. As well as made fin fillets with rocket poxy.
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FlyBy01

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I have a confession: I was going to fly naked for cert 1 this weekend. The launch was canceled due to the Coronavirus (aka. Zombie Apocalypse) precautions. Next attempt to fly is April 4th and 5th depending on my work schedule.

The sanding with continue until morale increases.
 

Speaknoevil

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I have a confession: I was going to fly naked for cert 1 this weekend. The launch was canceled due to the Coronavirus (aka. Zombie Apocalypse) precautions. Next attempt to fly is April 4th and 5th depending on my work schedule.

The sanding with continue until morale increases.
WTF?¿??¿??
 

K'Tesh

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The prong versions are cheaper. Again, I just turn them over. Don't like metal sticking out of the airframe.
My solution is to take a short scrap of 1/8" ply, drill an appropriately sized hole for the barrel of the T-nut, as well as smaller holes for the prongs, then glue a scrap of balsa to the ply. I then shape the balsa to match the curve of the inside of the body tube. I lube the bolt with some Vaseline, and screw it in from the backside so that it's proud of the top of the barrel. I drill (and harden) my body tube at the correct location, then glue the balsa/ply/T-nut assembly into the airframe, using the bolt to align it. After the glue has set, I remove the bolt from the inside, and screw it in place from the outside. If the parachute or shock cord is likely to get caught on it, I will use some epoxy putty to smooth the assembly's shape to allow proper deployment.
 

FlyBy01

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In this case the rail buttons are concealed by the fin-can. However I could have changed their location of the top rail button and used this method. I think this method is superior in added strength. I was looking to meet my own deadline to launch this weekend.
My solution is to take a short scrap of 1/8" ply, drill an appropriately sized hole for the barrel of the T-nut, as well as smaller holes for the prongs, then glue a scrap of balsa to the ply. I then shape the balsa to match the curve of the inside of the body tube. I lube the bolt with some Vaseline, and screw it in from the backside so that it's proud of the top of the barrel. I drill (and harden) my body tube at the correct location, then glue the balsa/ply/T-nut assembly into the airframe, using the bolt to align it. After the glue has set, I remove the bolt from the inside, and screw it in place from the outside. If the parachute or shock cord is likely to get caught on it, I will use some epoxy putty to smooth the assembly's shape to allow proper deployment.
 

Wallace

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What you described (I think?) should work just fine. For future reference, just get weld nuts and bend slightly to fit the i.d. Your life will be much simpler.You can also flatten or bend/break off the prongs on T nuts if that's all you have.
 

FlyBy01

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Nose cone in primer and body tube mostly sanded, alot more sanding to come.
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jd2cylman

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Honestly it’s a solid plan. L2 means a lot of different things to different people. I wanted my L2 at the time because I was primarily interested in clusters. Some want to do it with a rocket that will see mostly H’s, some want a big heavy and complex thing on L’s. The Goblin will eat K’s all day long but still fly on H’s.
FIFY... :););)
 

DMehalko

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Nice!! Love how versatile this thing is, on the first day out with mine I flew a g76, h115dm, I180, and a j270. Next flight will be a k535
 

Mach_Seven

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Good luck with the recovery. I'm going for my L1 Saturday with a JLCR as well. I have no problem packing a 42" chute and a 5' leader with the JLCR into my 3" rocket. It seems like every other flight is using one at our launches these days.

Here's a clip of the shake and deployment tests. (timestamped to 5:15)

 

Spitfire222

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Congratulations, great flight! Looks like you managed to get out to Battle Park's last launch of the season, if I'm not mistaken. I really wanted to attend a launch there, but I had other plans the weekends they were flying.

Out of curiosity, where in MD are you? I'm in VA, but have family in Frederick (where I grew up) and Rockville. I hope to make it out to MDRA sometime.
 

FlyBy01

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First a big Thank You to my new friends and Club Tripoli of Central Virginia. These flights would have not been possible without:
  • a borrowed JL Chute Release (mine is hanging in a tree and the 2nd for this launch was late delivery from the Post Office)
  • A borrowed motor case (It's all our vendor had in a J)
  • A lot of great advise!
  • Level 2 Certification Flight!
  • I cannot wait until next season!
 
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