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Coop

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I have. It is a fun kit. I drilled holes along the line where the TC fins were to go and then X-acto'd the excess (I must be remembering another plastic tailcone I'd hacked; according to the build diary I used a Dremel). I also cut back the TC a smidge and drum-sanded away enough to flush-mount an Aeropack. Gimme a few and I will find you a build diary (from my FB, but is public).

Here's the link.https://www.facebook.com/media/set/?set=a.10203658457127876.1073741829.1410264909&type=1&l=1766d21832

Later!

--Coop
 
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AfterBurners

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I have. It is a fun kit. I drilled holes along the line where the TC fins were to go and then X-acto'd the excess (I must be remembering another plastic tailcone I'd hacked; according to the build diary I used a Dremel). I also cut back the TC a smidge and drum-sanded away enough to flush-mount an Aeropack. Gimme a few and I will find you a build diary (from my FB, but is public).

Here's the link.https://www.facebook.com/media/set/?set=a.10203658457127876.1073741829.1410264909&type=1&l=1766d21832

Later!

--Coop
What about a Slimline retainer. I think reason I never went with a Slimline is there aren't many fit options. They only fit GL tubes I think all others its hit and miss on the fit you might get?
 

Coop

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I'd considered that, but having never handled one, I went with the Aeropack. When it was done and blended in and painted, I was rather pleased with how it turned out. Going to have to build another one of these, as mine had a CATO and screwed up the MMT pretty good.
 

AfterBurners

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I'd considered that, but having never handled one, I went with the Aeropack. When it was done and blended in and painted, I was rather pleased with how it turned out. Going to have to build another one of these, as mine had a CATO and screwed up the MMT pretty good.
What did you fly it on? I would like to get one too. I like the nostalgic design. Also it seems challenging. In the destructions how do they recommend cutting fin slots in the TC?
 

Coop

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I flew it mostly on G's, because I was at the small field whenever I launched it. I liked it on the dual-thrust, and various white motors.

I do not recall how the destructions say to cut the slots in the tail cone. It may be a melon baller, but I am pretty sure I didn't use that. Yes, seriously, melon baller may be in there.

What I would do is something like this: mark the airframe, Extend the line down onto the tailcone with tape. Mark the ends of the slots. Drill holes the width of the fin at each end. Connect the holes by using a Dremel with a cutting wheel, or X-Acto knife. It's not a difficult process, I assure you.

One thing I definitely remember doing was weighing both nose cones that came with the kit. I used the heavier cone up front, and the lighter one became the tailcone.

I think you will enjoy the build. It is a sharp looking bird when it is done and together. And it is not one of those kits that everybody has.

Later!

--Coop
 

AfterBurners

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I flew it mostly on G's, because I was at the small field whenever I launched it. I liked it on the dual-thrust, and various white motors.

I do not recall how the destructions say to cut the slots in the tail cone. It may be a melon baller, but I am pretty sure I didn't use that. Yes, seriously, melon baller may be in there.

What I would do is something like this: mark the airframe, Extend the line down onto the tailcone with tape. Mark the ends of the slots. Drill holes the width of the fin at each end. Connect the holes by using a Dremel with a cutting wheel, or X-Acto knife. It's not a difficult process, I assure you.

One thing I definitely remember doing was weighing both nose cones that came with the kit. I used the heavier cone up front, and the lighter one became the tailcone.

I think you will enjoy the build. It is a sharp looking bird when it is done and together. And it is not one of those kits that everybody has.

Later!

--Coop
Yeah I might get it after I get rid of some of the stuff I don't need... I keep telling myself its a want not a need.
 

emckee

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Someone in our club had/flew one of these a couple years ago. From my (bystander's) perspective, the most challenging part was likely the horizontal, off-axis fin, shown on the aft-rear section of the picture. Because this is like a slat, it acts as an airfoil and will rapidly pull the rocket off of a vertical trajectory if it is canted off the rocket's axis. I'd be interested in hearing techniques to ensure that fin/airfoil is on-axis!

I watched two separate flights of this fellow's kit. Each time, it arc'd over after leaving the rail and landed somewhat down-range, under thrust.
 

AfterBurners

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Someone in our club had/flew one of these a couple years ago. From my (bystander's) perspective, the most challenging part was likely the horizontal, off-axis fin, shown on the aft-rear section of the picture. Because this is like a slat, it acts as an airfoil and will rapidly pull the rocket off of a vertical trajectory if it is canted off the rocket's axis. I'd be interested in hearing techniques to ensure that fin/airfoil is on-axis!

I watched two separate flights of this fellow's kit. Each time, it arc'd over after leaving the rail and landed somewhat down-range, under thrust.
Coop did you have any issues with yours as mentioned?
 

Coop

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Nope--mine flew fantastically. If the trajectory was such, I'd suspect a thrust:weight ratio issue rather than that single 1/2" wide slat. I'd notice a bit of an arc if I went with something like a G-58, but never with the G-107 or G-126--yes, I would run adapters in this to fly it off of 24mm G reloads--and never had it come in ballistic thrusting into the ground.

If the fins were stack-sanded and tips squared, there's no reason why this should be at a canted angle. If you're concerned that it may be an issue, and don't trust your eyeball, I suppose one could secure the airframe in something and make that level, then level out the slat to the confirmed level airframe... but to be honest, I never thought of doing this at the time. I eyeballed it and called it good.

If I were to build another (and believe me, I will; I miss flying this thing), I'd spend more time trying to mount rail buttons on this without violating its beautiful lines. Serious consideration would be given to the Mayhem fly-away variety (which were not available in this airframe size when I built mine).



Later!

--Coop
 
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AfterBurners

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Nope--mine flew fantastically. If the trajectory was such, I'd suspect a thrust:weight ratio issue rather than that single 1/2" wide slat. I'd notice a bit of an arc if I went with something like a G-58, but never with the G-107 or G-126--yes, I would run adapters in this to fly it off of 24mm G reloads--and never had it come in ballistic thrusting into the ground.

If the fins were stack-sanded and tips squared, there's no reason why this should be at a canted angle. If you're concerned that it may be an issue, and don't trust your eyeball, I suppose one could secure the airframe in something and make that level, then level out the slat to the confirmed level airframe... but to be honest, I never thought of doing this at the time. I eyeballed it and called it good.


Later!

--Coop
Just curious...I eyeball everything too
 

Pem Tech

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This looks like a fun and challenging kit. Reading the parts description it looks like nothing but quality parts are included.

https://www.pembertontechnologies.com/the-space-ark/

Has anyone here built the kit. I think the challenge would be cutting the slots in the boat tail? Although I think a Dremel would do the trick.
I have. It is a fun kit. I drilled holes along the line where the TC fins were to go and then X-acto'd the excess (I must be remembering another plastic tailcone I'd hacked; according to the build diary I used a Dremel). I also cut back the TC a smidge and drum-sanded away enough to flush-mount an Aeropack. Gimme a few and I will find you a build diary (from my FB, but is public).

Here's the link.https://www.facebook.com/media/set/?set=a.10203658457127876.1073741829.1410264909&type=1&l=1766d21832

Later!

--Coop
Oh yeah Afterburners, Coop is right on the nose, she is a great bird to build and fly. Labor intensive, but well worth the blood, sweat and Llama bites.The Destructions suggest the drill thing Coop mentioned but a dremel with cutting wheels make cleaner straighter fin slots. That will be changed in the Destructions soon.

Love the idea of a of a Slimline retainer, will have to put one on my next Space Ark build.


I flew it mostly on G's, because I was at the small field whenever I launched it. I liked it on the dual-thrust, and various white motors.

I do not recall how the destructions say to cut the slots in the tail cone. It may be a melon baller, but I am pretty sure I didn't use that. Yes, seriously, melon baller may be in there.


I think you will enjoy the build. It is a sharp looking bird when it is done and together. And it is not one of those kits that everybody has.

Later!

--Coop
Coop, it isn't a mellon baller, it is an ice cream scoop. I'm very disappointed with you.

Afterburners, the Space Ark (SA) will fly great on a wide array of motors. Minimum G64 all the way to an I240. Did my L1 on an H153.
L1prep_DSC_4770CR.jpgPostL1_DSC_4796CR.jpgSpaceArkL1flight_DSC_4786CR.jpg

Yeah I might get it after I get rid of some of the stuff I don't need... I keep telling myself its a want not a need.
*you neeeeeed oooooone*
*you neeeeeed oooooone*
*you neeeeeed oooooone*

Someone in our club had/flew one of these a couple years ago. From my (bystander's) perspective, the most challenging part was likely the horizontal, off-axis fin, shown on the aft-rear section of the picture. Because this is like a slat, it acts as an airfoil and will rapidly pull the rocket off of a vertical trajectory if it is canted off the rocket's axis. I'd be interested in hearing techniques to ensure that fin/airfoil is on-axis!

I watched two separate flights of this fellow's kit. Each time, it arc'd over after leaving the rail and landed somewhat down-range, under thrust.
Nope--mine flew fantastically. If the trajectory was such, I'd suspect a thrust:weight ratio issue rather than that single 1/2" wide slat. I'd notice a bit of an arc if I went with something like a G-58, but never with the G-107 or G-126--yes, I would run adapters in this to fly it off of 24mm G reloads--and never had it come in ballistic thrusting into the ground.

If the fins were stack-sanded and tips squared, there's no reason why this should be at a canted angle. If you're concerned that it may be an issue, and don't trust your eyeball, I suppose one could secure the airframe in something and make that level, then level out the slat to the confirmed level airframe... but to be honest, I never thought of doing this at the time. I eyeballed it and called it good.

If I were to build another (and believe me, I will; I miss flying this thing), I'd spend more time trying to mount rail buttons on this without violating its beautiful lines. Serious consideration would be given to the Mayhem fly-away variety (which were not available in this airframe size when I built mine).



Later!

--Coop
emckee, of the four SA's I've built over the years I've never experienced this problem, nor been made aware of any aerodynamic problems caused by the crossbar. I did have troubles, when the SA was first introduced, with the crossbar interfering with the launch rod. But that was far away and many Llamas ago. If you have any images or the contact info of the person who was having the difficulty I'd be very interested to hear more.

Coop, the next SA version will come with rail buttons.
:D
 

Coop

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Another possible reason for such a trajectory as described above is the rod length. How long were the rods at the club where you witnessed this, emckee? I had to use shorter rods a couple of times, which is why I went with the dual-thrust or heavy-hitting whites to get it up to stable speed quickly. I could see a low-thrust motor coupled with a short rod sending a rocket on such an arc... horizontal stabilizers or no. I remember doing that with a scratch-built BT-70 thing I tried putting up on a C6 instead of a C-11. Since then, I've payed a lot more attention to the velocity at the end of the rod (or rail).

Layne: Ice cream scoop--damn. My apologies--don't make me suffer in the inquisition!


Later!

--Coop
 

AfterBurners

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Don't worry I plan on getting one and considering ordering an extra nose/TC in case I Goober it with the Dremel. Something about the kit brings you back in time and it has a very "nostalgic feel" to it. Very cool kit indeed. Will a Slimline fit the motor tube or you think it will be sloppy. I don't know the OD specs. If it's tight I don't mind sanding it to fit, in fact that's how you get the best builds.

What kind of tube is used for the air frame? Is it phenolic?

BTW - I like your pencil holder. Very cool.
 

MaxQ

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I love the silver/chrome finish on the built up in the pictures,...what paint did you use?

I'm very interested in getting one.
 

AfterBurners

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Oh yeah Afterburners, Coop is right on the nose, she is a great bird to build and fly. Labor intensive, but well worth the blood, sweat and Llama bites.The Destructions suggest the drill thing Coop mentioned but a dremel with cutting wheels make cleaner straighter fin slots. That will be changed in the Destructions soon.

Love the idea of a of a Slimline retainer, will have to put one on my next Space Ark build.




Coop, it isn't a mellon baller, it is an ice cream scoop. I'm very disappointed with you.

Afterburners, the Space Ark (SA) will fly great on a wide array of motors. Minimum G64 all the way to an I240. Did my L1 on an H153.
View attachment 317276View attachment 317277View attachment 317278



*you neeeeeed oooooone*
*you neeeeeed oooooone*
*you neeeeeed oooooone*





emckee, of the four SA's I've built over the years I've never experienced this problem, nor been made aware of any aerodynamic problems caused by the crossbar. I did have troubles, when the SA was first introduced, with the crossbar interfering with the launch rod. But that was far away and many Llamas ago. If you have any images or the contact info of the person who was having the difficulty I'd be very interested to hear more.

Coop, the next SA version will come with rail buttons.
:D
What kind of tube is used for the air frame? Is it phenolic?
 

Pem Tech

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I love the silver/chrome finish on the built up in the pictures,...what paint did you use?

I'm very interested in getting one.
The paint was an accursed chrome by Krylon, I believe. Tried several different brands but they all had the same issues. The finish was beautiful, until you touched it, any contact with skin and the spot would turn milky. The paints never dried hard, they all remained so soft that anything laid on, or pressed against the finish would leave an impression.
I've heard Duplico (sp) does not have these issues.
 

Pem Tech

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Don't worry I plan on getting one and considering ordering an extra nose/TC in case I Goober it with the Dremel. Something about the kit brings you back in time and it has a very "nostalgic feel" to it. Very cool kit indeed. Will a Slimline fit the motor tube or you think it will be sloppy. I don't know the OD specs. If it's tight I don't mind sanding it to fit, in fact that's how you get the best builds.

What kind of tube is used for the air frame? Is it phenolic?

BTW - I like your pencil holder. Very cool.
The tube is heavy walled paper, like LOC.
Nostalgia, yes, nostalgia and retro, that is our speciality.
The OD on the MM is 1.6400".

Pencil holder?
 

AfterBurners

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I got an email from GL apparently the OD on their 38 Slimline is 1.654 in. I would imagine maybe one wrap of tape on the LOC mmt would make it fit. Unlike AT which makes sizes for different types of manufactures tubes, GL just makes them for their mmt's unless I'm wrong ?
 

emckee

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I'll see what I can dig up. As I mentioned, my note was my observations on a couple of unfortunate events.

I love the design and expect I'll end up with one eventually, or perhaps the Bucky Jones or ... well, there are a lot of awesome kits.

-e
 

AfterBurners

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If I was to purchase a Slimline retainer for this kit and arranged it to where it will fit flush with the tail cone, would the heat from the flames cause any damage to the tail cone or vertical stabilizer? The nozzle is right there on the end. That would be my concern, but I think it would be visually appealing for sure. It would be very clean and aerodynamic.
 

Coop

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I made mine with an Aeropack, not a Slimline, but other than fingerprints and soot, I saw no problems.

Later!

--Coop
 
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