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Anycubic Kobra 2 Max sale for $429
1/26th Scale Space Shuttle (full stack)
- Thread starter sambatterman
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Why are you thinking it needs to be so heavy at this scale, especially unpowered? Comparing to Dave Shaefers ME-163 that is fiberglass and also has the tail weight of an I-161 it has to balast for which is about 5# rtf with motor, 60" span. Also, I think making the body flap movable is not really a benefit, I think it was mostly effective during re-entry for pitch control, not as much at normal flight speeds, could save some tail weight there..
Frank
Frank
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Hey Frank - thanks for watching this thread. 10# is my goal for a first build like this - I know it will get lighter as I figure stuff out. Think of this build as the "Enterprise" test shuttle before anything else. I have to figure out the autopilot, the RC features - like gear doors, elevons, rudder and the overall structure. This version may not fly, but it's necessary for me to figure out the overall structure, how it connects to the External Tank. How it would separate from the ET and the support points on the ET itself. The body flap won't be functional, and I agree that it won't impact performance at this scale. One of the reasons I'm going all out on the mold process is to figure out how to make this lighter as I go.
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A Quick Finish of the Orbiter Cabin Mockup
Thought I would take advantage of learning what it's like to finish a carbon fiber model, including cutting out the nose gear doors with a Dremel. Carbon fiber (especially painted) is less forgiving to knife knicks than fiberglass.
This will never be used - it's 60% of the full size I'm going for, but just wanted to see what it would look like...
Thought I would take advantage of learning what it's like to finish a carbon fiber model, including cutting out the nose gear doors with a Dremel. Carbon fiber (especially painted) is less forgiving to knife knicks than fiberglass.
This will never be used - it's 60% of the full size I'm going for, but just wanted to see what it would look like...
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Shiny new 3d printer and molds
Okay, so it's been a minute, but finally got my new 3D printer - an AnyCubic Kobra 2 Max with a huge build volume (450mmx450mmx500mm). It's super-fast and has a ton of great features. So, I started printing the molds for the 1/26th scale orbiter. Here's a week's worth of printing - burned through 8 reels of PLA (normal spool). The bottom molds, rear fuselage and rudder are done. Currenty working on the wings and the top of the fuselage.
Here's the Fusion 360 model with the mold blocks (see my thread above about how to subtract the tool from the mold).
Okay, so it's been a minute, but finally got my new 3D printer - an AnyCubic Kobra 2 Max with a huge build volume (450mmx450mmx500mm). It's super-fast and has a ton of great features. So, I started printing the molds for the 1/26th scale orbiter. Here's a week's worth of printing - burned through 8 reels of PLA (normal spool). The bottom molds, rear fuselage and rudder are done. Currenty working on the wings and the top of the fuselage.
Here's the Fusion 360 model with the mold blocks (see my thread above about how to subtract the tool from the mold).
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NTP2
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You got a picture of the printer itself?
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NTP2
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I am very very jealous…
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Working on the orbiter’s aft fuselage
Working on this thing is disorienting - where to start? Now that the 3D printing molds are done, it's actually time to start fabricating the orbiter. Here's a reference photo of the aft part, because, after all, almost all rocket builds start with the motor mount.
The aft fuselage is a wacky shape - way different than the rest of the vehicle - very faceted and angular.
So, here's the rear of the fuselage. Three holes for 6" x 38mm motors. The drill points on the bottom are for the body flap, which is largely facbricated from 3D printed parts.
Gluing up the ribs for the body flap. Notice the holes for the dowels that will strength the part laterally.
Getting all the parts glued and aligned was a little tricky.
38mm motor mount phenolic tubes cut to 7". They have Aerotech retainers that screw on the "firey" end to keep the motor in the tube during flight.
3D printed engine bells add to the realism.
The motors are JB Welded to the MMT bulkhead. This allows for optional propulsive assist at launch, or not. Doesn't weigh very much.
Working on this thing is disorienting - where to start? Now that the 3D printing molds are done, it's actually time to start fabricating the orbiter. Here's a reference photo of the aft part, because, after all, almost all rocket builds start with the motor mount.
The aft fuselage is a wacky shape - way different than the rest of the vehicle - very faceted and angular.
So, here's the rear of the fuselage. Three holes for 6" x 38mm motors. The drill points on the bottom are for the body flap, which is largely facbricated from 3D printed parts.
Gluing up the ribs for the body flap. Notice the holes for the dowels that will strength the part laterally.
Getting all the parts glued and aligned was a little tricky.
38mm motor mount phenolic tubes cut to 7". They have Aerotech retainers that screw on the "firey" end to keep the motor in the tube during flight.
3D printed engine bells add to the realism.
The motors are JB Welded to the MMT bulkhead. This allows for optional propulsive assist at launch, or not. Doesn't weigh very much.
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Aligning the aft fuselage parts
So, yeah, the rear fuselage has a lot going on. Here's a Fusion 360 visualization of the rear fuselage and neighboring systems (wings, retracts, etc.). I decided to use the rear fuselage mold to help with aligning all the parts, because of the angularness of the aft fuselage.
So, here's the nearly finished rear bulkhead with the 3 7" x 38mm MMTs and engine bells. The body flap internals are seen directly below.
This mold will be super useful in allowing me to glue the rear bulkhead into the carbon fiber mold (already cast) and ensure I get the right angle on the rear bulkhead. This is critical for the rudder placement and the inner elevons, not to mention aligning with the belly component (shown in the distance in white).
Here's a peek behind the curtain. If you look closely, you can see the carbon fiber mold inside the 3D printed mold master.
The top rudder covers align exactly with the top of the rear bulkhead.
Here's the bulkhead that the aft fuselage will interface with - you can clearly see the open voids that are curved and that's where the OMS pods sit.
There is no way I could build this model without visualizing it in Fusion360 - I can't recommend this tool enough to our hobby.
So, yeah, the rear fuselage has a lot going on. Here's a Fusion 360 visualization of the rear fuselage and neighboring systems (wings, retracts, etc.). I decided to use the rear fuselage mold to help with aligning all the parts, because of the angularness of the aft fuselage.
So, here's the nearly finished rear bulkhead with the 3 7" x 38mm MMTs and engine bells. The body flap internals are seen directly below.
This mold will be super useful in allowing me to glue the rear bulkhead into the carbon fiber mold (already cast) and ensure I get the right angle on the rear bulkhead. This is critical for the rudder placement and the inner elevons, not to mention aligning with the belly component (shown in the distance in white).
Here's a peek behind the curtain. If you look closely, you can see the carbon fiber mold inside the 3D printed mold master.
The top rudder covers align exactly with the top of the rear bulkhead.
Here's the bulkhead that the aft fuselage will interface with - you can clearly see the open voids that are curved and that's where the OMS pods sit.
There is no way I could build this model without visualizing it in Fusion360 - I can't recommend this tool enough to our hobby.
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Shuttle: bottom fuselage shell
Well, after nearly two months of printing, gluing up and aligning, I have a result for the bottom of the orbiter fuselage.
Steps I took are below...
First, about 2 weeks of 3d printing molds of the bottom half of the shuttle fuselage. You can see I did it in pieces - even with a Anycubic Max Pro with a 450mm vertical build volume. I used long steel angle brackets to help align the parts as they glued up and cured.
After all the glue up, I sanded and puttied and sanded again to smooth the mold.
Before I laid down the carbon fiber, I rubbed Fiberglast mold release in two coats and let it dry in between coats.
Here's two layers of carbon fiber and some carbon fiber tape along edges. I used a lot of clamps and thin balsa strips on top of the blotter to keep the walls nice and tight during cure. You can see the nose cone is another part and that was the hard part of releasing the hold finally from this plastic prison. It took me two hours to get the shell out. They must edit that portion out of most videos. It doesn't just "pop" out.
Here's the lower fuselage free of the mold. I also used Aramid honeycomb to make the structure super strong, but also super light. I will have the actual weight here later today (I don't have a scale that sensitive (in grams), but it's less than an empty pizza box.
UPDATE: Weight of the lower fuselage is 714g (or 1.5 pounds). Considering any other method would be 5-10x that number, I'm pretty happy.
Notice that I needed to do some patching on the fuselage and also that I glued on the cast nose cone. Once I get some primer on this thing you won't notice these blemishes.
Here's another couple of views...I'm especially happy with how the wing gloves came out - and honestly, that's the area I was most concerned about.
Again, huge thanks to Fusion 360 and 3D Printing. I know this has been done before (maybe not at this scale) without those tools and I am astonished at those and their craftsmanship.
Next up - the top fuselage and getting some bulkheads in place.
Well, after nearly two months of printing, gluing up and aligning, I have a result for the bottom of the orbiter fuselage.
Steps I took are below...
First, about 2 weeks of 3d printing molds of the bottom half of the shuttle fuselage. You can see I did it in pieces - even with a Anycubic Max Pro with a 450mm vertical build volume. I used long steel angle brackets to help align the parts as they glued up and cured.
After all the glue up, I sanded and puttied and sanded again to smooth the mold.
Before I laid down the carbon fiber, I rubbed Fiberglast mold release in two coats and let it dry in between coats.
Here's two layers of carbon fiber and some carbon fiber tape along edges. I used a lot of clamps and thin balsa strips on top of the blotter to keep the walls nice and tight during cure. You can see the nose cone is another part and that was the hard part of releasing the hold finally from this plastic prison. It took me two hours to get the shell out. They must edit that portion out of most videos. It doesn't just "pop" out.
Here's the lower fuselage free of the mold. I also used Aramid honeycomb to make the structure super strong, but also super light. I will have the actual weight here later today (I don't have a scale that sensitive (in grams), but it's less than an empty pizza box.
UPDATE: Weight of the lower fuselage is 714g (or 1.5 pounds). Considering any other method would be 5-10x that number, I'm pretty happy.
Notice that I needed to do some patching on the fuselage and also that I glued on the cast nose cone. Once I get some primer on this thing you won't notice these blemishes.
Here's another couple of views...I'm especially happy with how the wing gloves came out - and honestly, that's the area I was most concerned about.
Again, huge thanks to Fusion 360 and 3D Printing. I know this has been done before (maybe not at this scale) without those tools and I am astonished at those and their craftsmanship.
Next up - the top fuselage and getting some bulkheads in place.
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NTP2
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Is the yellow stuff, the honey comb stuff you use to make composts stronger?
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Yep
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Question for the RC guys - outer and inner elevons
A message to the Radio Control gang out there. The orbiter wings are essentially 12" wide and the real orbiter has outboard and inboard elevons. What are the advantages and disadvantages of doing the scale thing, or should I just go with one single elevon?
Below you can see the top left-wing skin with the ribs I will be using for interior structure.
Interested in your opinions or any empirical evidence you might have... Thanks.
A message to the Radio Control gang out there. The orbiter wings are essentially 12" wide and the real orbiter has outboard and inboard elevons. What are the advantages and disadvantages of doing the scale thing, or should I just go with one single elevon?
Below you can see the top left-wing skin with the ribs I will be using for interior structure.
Interested in your opinions or any empirical evidence you might have... Thanks.
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Helpful tools for mold making.
When I started with this project, I watched a lot of videos and have learned a number of things that I want to share with the community.
Besides a long, sharp blade for cutting the shells loose of their molds and gloves to protect from carbon fiber splinters, I highly recommend the following tools:
When I started with this project, I watched a lot of videos and have learned a number of things that I want to share with the community.
Besides a long, sharp blade for cutting the shells loose of their molds and gloves to protect from carbon fiber splinters, I highly recommend the following tools:
- Roller with foam pads: Besides a disposable brush for applying epoxy, I recommend a roller for pushing and pulling the epoxy into the fiber (glass or carbon) in a uniform way. Much better results than just a brush.
- Thin, miniature crowbar/chisel: Useful for breaking a cured shell from the mold without damaging the result. Highly recommended.
- Mold Release Agent: Apply a few coats to the mold and allow to dry before applying epoxy and fabric. It doesn't make it "pop" out like a non-stick pad, but I assume not using this agent would be horrendous.
- Scotch Super 77: Fast spray adhesive for holding fabric on vertical surfaces like walls and curves as epoxy cures.
- Scotch Spray Mount: Use like Super 77, but for re-positioning fabric or templates.
- Carbon Fiber Tape: I don't use the impregnated tape, but this is useful for adding additional strength to edges.
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Shuttle - An Elevator Study
Originally, I had planned on printing the elevon ribs and laying flat carbon fiber across the surface in a more traditional way to create control surfaces on any RC airplane. As I looked at it, printing the elevons as "solids" turned out to be just as lightweight and each elevon is perfect in shape.
I created a simple test jig to test how all the parts would fit together and work. I'm using two 1/8" heavy duty hinges and control horns. The servos will be embedded in the wing straightforward from the control horn.
I decided to go with outer and inner elevons just like the real thing. We'll see if it's overkill.
Originally, I had planned on printing the elevon ribs and laying flat carbon fiber across the surface in a more traditional way to create control surfaces on any RC airplane. As I looked at it, printing the elevons as "solids" turned out to be just as lightweight and each elevon is perfect in shape.
I created a simple test jig to test how all the parts would fit together and work. I'm using two 1/8" heavy duty hinges and control horns. The servos will be embedded in the wing straightforward from the control horn.
I decided to go with outer and inner elevons just like the real thing. We'll see if it's overkill.
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Casting the Upper Fuselage in Carbon Fiber
It took a week to print the upper fuselage molds. I glued them together with Gorilla Glue - way cheaper than JB Weld and sanded it smooth. Used wax and mold release and then layered 3 layers of carbon fiber with West Systems epoxy. Because the payload bay is so long and needs to be perfectly straight on the walls, I decided to use two long 1/4 boards as forms and clamped them down tight.
A tip I would recommend. After the carbon goes to leather - about 5 hours in, cut the edges with a sharp blade. When it's totally cured, I used a disk sander and sanded the carbon while it's still inside the mold. This gives you perfectly sharp edges, and no finishing is needed after you pop it out of the mold. Make sure you use eye protection and wear a mask or respirator because carbon dust is toxic.
And here's the final shape. Pretty happy with it. It's strong and light - weighs in around 30 grams. Still have some filling and sanding to do with SuperFill and will share those photos soon.
It took a week to print the upper fuselage molds. I glued them together with Gorilla Glue - way cheaper than JB Weld and sanded it smooth. Used wax and mold release and then layered 3 layers of carbon fiber with West Systems epoxy. Because the payload bay is so long and needs to be perfectly straight on the walls, I decided to use two long 1/4 boards as forms and clamped them down tight.
A tip I would recommend. After the carbon goes to leather - about 5 hours in, cut the edges with a sharp blade. When it's totally cured, I used a disk sander and sanded the carbon while it's still inside the mold. This gives you perfectly sharp edges, and no finishing is needed after you pop it out of the mold. Make sure you use eye protection and wear a mask or respirator because carbon dust is toxic.
And here's the final shape. Pretty happy with it. It's strong and light - weighs in around 30 grams. Still have some filling and sanding to do with SuperFill and will share those photos soon.
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Starting on the Bulkheads
Using Fusion360, I modeled the bulkheads that will support the fuselage and wings. For orientation purposes you can see the nose at the right and the aft section on the left. There are 5 3D printed bulkheads and 4 carbon fiber 1/2" tubes that run laterally. The bulkheads rest on the floor of the lower fuselage (with JB Weld) and also on lateral supports that stretch from the aft MMT bulkhead panel - you can see this marked in blue. The blue supports will also help me align the wings perfectly.
This is a dry fit - nothing is glued down. Just making sure it all fits nicely and is level. If you look toward the aft, you can see the first look at the Right OMS pod (taped).
Here's a view of the MMT assembly and the internal wing supports that run from the rear of the vehicle to the nose. Lots of clean up needed, but you can see some progress.
Using Fusion360, I modeled the bulkheads that will support the fuselage and wings. For orientation purposes you can see the nose at the right and the aft section on the left. There are 5 3D printed bulkheads and 4 carbon fiber 1/2" tubes that run laterally. The bulkheads rest on the floor of the lower fuselage (with JB Weld) and also on lateral supports that stretch from the aft MMT bulkhead panel - you can see this marked in blue. The blue supports will also help me align the wings perfectly.
This is a dry fit - nothing is glued down. Just making sure it all fits nicely and is level. If you look toward the aft, you can see the first look at the Right OMS pod (taped).
Here's a view of the MMT assembly and the internal wing supports that run from the rear of the vehicle to the nose. Lots of clean up needed, but you can see some progress.
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This is true master-level work, I am in awe. And to think that now almost 4 years ago, you pointed out to newbie me that the V2 had a pointed nose cone, not rounded as in the Estes kit. I couldn't "unsee" that - and my brother-in-law thinks, "Boy, people would be really impressed if they saw you fixed that!" 
The V2 did turn out very nice, though, and I am watching and hoping you have an even greater level of success with this project. Go, man, go!
The V2 did turn out very nice, though, and I am watching and hoping you have an even greater level of success with this project. Go, man, go!- Joined
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Tom - would love to see a picture of the finished V2 is you have one. I used a nose cone on my Jayhawk project that has a rounded off nose - it's getting more and more difficult to buy nosecones that are scale for body tubes > 5". Thanks for your encouragement. This is a crazy project.This is true master-level work, I am in awe. And to think that now almost 4 years ago, you pointed out to newbie me that the V2 had a pointed nose cone, not rounded as in the Estes kit. I couldn't "unsee" that - and my brother-in-law thinks, "Boy, people would be really impressed if they saw you fixed that!"
Sam, I fouled up. It was another user "samb" that that pointed out the pointed nose cone to me and showed me his. But anyway, the finished rocket is here.
I just stumbled on this project. I LOVE seeing flying shuttle models. I search then out every few years. Coincidentally this is the 30th anniversary year of the 1/40 one I designed and flew while in Grad school. Readers here may have seen the videos on YouTube. Its my channel. Here is a link to the Sport Rocketry article we wrote and links to the videos. We always talked about building a 1/20 orbiter to fly. I even have a set of my plans scaled up somewhere BTW, the stack weighed a little over 6 pounds at liftoff. Two RC receivers, two batteries, two servos, 2 timers, 4 electronic Flash bulb charges. No fins. H70W.
http://www.spacecraftreplicas.com/shuttle
http://www.spacecraftreplicas.com/shuttle/history
Like Frank (burkefj) I also have hundreds of flights on all sizes of shuttles. I stay active in RC modeling and have recently flown shuttle models. I'll try to check back here soon but let me know if you have any questions or need any help. You can email me also. The website is pretty old but the second email listed is good and I check it daily.
Scott
BTW, the stack weighed a little over 6 pounds at liftoff. Two RC receivers, two batteries, two servos, 2 timers, 4 electronic Flash bulb charges. No fins. H70W.http://www.spacecraftreplicas.com/shuttle
http://www.spacecraftreplicas.com/shuttle/history
Like Frank (burkefj) I also have hundreds of flights on all sizes of shuttles. I stay active in RC modeling and have recently flown shuttle models. I'll try to check back here soon but let me know if you have any questions or need any help. You can email me also. The website is pretty old but the second email listed is good and I check it daily.
Scott
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Scott would be my go to guy for Shuttle stack questions, thrust lines in a full stack etc since he is one of the few(alive) who have actually flown one successfully.
I had found those videos a few years back as a fairly new BAR and was quite in awe! Glad to meet the brains behind it all. Now I'd love a really big, detailed, 5-5-1 Saturn V (who wouldn't) but the special challenges of the Shuttle, the weight and drag asymmetries, plus adding in RC aircraft capability - successfully - AND inspiring a bunch of high schoolers along the way - I could hope for 1/10th the legacy. Good on you! (I never could get that left-hand, right hand swap down when the thing was coming at me...).I just stumbled on this project. I LOVE seeing flying shuttle models. I search then out every few years. Coincidentally this is the 30th anniversary year of the 1/40 one I designed and flew while in Grad school. Readers here may have seen the videos on YouTube. Its my channel. Here is a link to the Sport Rocketry article we wrote and links to the videos. We always talked about building a 1/20 orbiter to fly. I even have a set of my plans scaled up somewhere
http://www.spacecraftreplicas.com/shuttle
http://www.spacecraftreplicas.com/shuttle/history
Like Frank (burkefj) I also have hundreds of flights on all sizes of shuttles. I stay active in RC modeling and have recently flown shuttle models. I'll try to check back here soon but let me know if you have any questions or need any help. You can email me also. The website is pretty old but the second email listed is good and I check it daily.
Scott
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Ribs & Wings
A lot going on this weekend, but I finished the assembly of the ribs and spars for the shuttle wings. I decided to print the ribs and use 1/4" dowels to strengthen the wing. I also used 3 1/2" carbon fiber tubes to connect to the fuselage. You can see the test rig I used for the elevators as a stand in. I also trimmed two the ribs to allow for the servos for controlling the inner and outer elevons. Each wing is super light - about 280 grams each. Each wing will be JB Welded to the carbon fiber skin from the wing molds.
Here's a dry test for connecting the wings to the fuselage with the carbon fiber spars sliding into the mating holes on the longeron that runs 2/3 of the way up the lower section of the fuselage.
A lot going on this weekend, but I finished the assembly of the ribs and spars for the shuttle wings. I decided to print the ribs and use 1/4" dowels to strengthen the wing. I also used 3 1/2" carbon fiber tubes to connect to the fuselage. You can see the test rig I used for the elevators as a stand in. I also trimmed two the ribs to allow for the servos for controlling the inner and outer elevons. Each wing is super light - about 280 grams each. Each wing will be JB Welded to the carbon fiber skin from the wing molds.
Here's a dry test for connecting the wings to the fuselage with the carbon fiber spars sliding into the mating holes on the longeron that runs 2/3 of the way up the lower section of the fuselage.
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Hi Scott - great to make your acquittance. Your flights and work on the shuttle stack are amazing (and legendary) - and, boy, do I have a lot of questions for you...I just stumbled on this project. I LOVE seeing flying shuttle models. I search then out every few years. Coincidentally this is the 30th anniversary year of the 1/40 one I designed and flew while in Grad school. Readers here may have seen the videos on YouTube. Its my channel. Here is a link to the Sport Rocketry article we wrote and links to the videos. We always talked about building a 1/20 orbiter to fly. I even have a set of my plans scaled up somewhere
http://www.spacecraftreplicas.com/shuttle
http://www.spacecraftreplicas.com/shuttle/history
Like Frank (burkefj) I also have hundreds of flights on all sizes of shuttles. I stay active in RC modeling and have recently flown shuttle models. I'll try to check back here soon but let me know if you have any questions or need any help. You can email me also. The website is pretty old but the second email listed is good and I check it daily.
Scott
First, how much in the orbiter weigh for your grad school flight?
Secondly, how did you separate the orbiter from the External Tank (and the SRBs since we are on the topic).
Thirdly, I need to work out the thrust line of my stack (1/26th scale) - I have all the parts now but have put this off and focused on the orbiter build, but it won't be long before I make it back to the ET. What are your recommendations for this thrust line - I am planning on using L2200Gs in the SRB and probably a low M in the External Tank. The orbiter can provide thrust also (3x36mm).
I think there is a weight breakdown in the Sport Rocketry article. Its on my website. Memory says the orbiter was around 2 pounds. One servo pulled pins from the three attach points. The attach points on the ET were aluminum. The pins were basic music wire. The orbiter pilot controlled its own release. The SRB's were basically the same. The ET pilot jettisoned them around engine burnout.
I was in Florida last week. I spent some time with one of the guys that helped on the project. We reminisced and couldn't believe it was 30 years ago. It Seems like just a few months have passed.
We only had one thrust line so it was a little easier. You need to sum the moments of the engines (Force x Distance) and make sure they react through the stack CG. This can be a bit iterative. We guessed at this on our first stack that we flew based on some rough calculations and measurements. There is video on my YouTube channel. We tweaked it with ballast and tweaked the thrust line of the motor in the ET. When we thought it flew pretty straight, we modified the final two flight articles to match. We sold several kits to benefit the School. Some of the builders wanted motors in the SRB's and Orbiter. We always recommended using small motors for the effects and rely mostly on the main one in the ET. This way any failures or start delays would not affect the flight. i thihnk Steve Eves was the only person to ever attempt to fly one. He added a ton of weight to it and was only partially successful as far as I remember.
We guarded the original plans for many years. Without getting in the politics, Ill post them. They have been posted before but its been a minute. Maybe you'll learn something. They are not complete enough to build one as prefab parts were included in the kit the plans came with. I'm glad we established communications. I look forward to following your project. Let me know if I can do anything else.
Please don't quote my posts so I can edit them, and its just rude
Scott Todd
I was in Florida last week. I spent some time with one of the guys that helped on the project. We reminisced and couldn't believe it was 30 years ago. It Seems like just a few months have passed.
We only had one thrust line so it was a little easier. You need to sum the moments of the engines (Force x Distance) and make sure they react through the stack CG. This can be a bit iterative. We guessed at this on our first stack that we flew based on some rough calculations and measurements. There is video on my YouTube channel. We tweaked it with ballast and tweaked the thrust line of the motor in the ET. When we thought it flew pretty straight, we modified the final two flight articles to match. We sold several kits to benefit the School. Some of the builders wanted motors in the SRB's and Orbiter. We always recommended using small motors for the effects and rely mostly on the main one in the ET. This way any failures or start delays would not affect the flight. i thihnk Steve Eves was the only person to ever attempt to fly one. He added a ton of weight to it and was only partially successful as far as I remember.
We guarded the original plans for many years. Without getting in the politics, Ill post them. They have been posted before but its been a minute. Maybe you'll learn something. They are not complete enough to build one as prefab parts were included in the kit the plans came with. I'm glad we established communications. I look forward to following your project. Let me know if I can do anything else.
Please don't quote my posts so I can edit them, and its just rude
Scott Todd
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Wings and Blue Cheese
With the ribs in place, I installed the servos for the inner and outer elevons and put a protective, thin carbon fiber cover over the devices to keep them clean for the rest of the assembly. I used a disc sander to profile the spray foam. The wings weigh 1.3 pounds each. Pretty happy with how they are turning out.
I smeared JB Weld all over the ribs and the leading edge and placed the carbon fiber cover of the airfoil on top, making sure to align the edges carefully. I then used most of my small clamps to make sure this was going to be a good adhesion.
Here's the completed cover. There was still a lot of sanding and filling to be done on the leading edge. I covered the servo arms with tape to protect them during sanding.
Here's a dry assembly of the right wing. You can see the unsanded, but Super-filled leading edge in this photo. The two carbon fiber tubes in the aft of the wing are used to align the wing to the body. The tip of the wing will "tuck" into the wing glove (sometimes called a strake) on the orbiter body.
The final, thick carbon skin of the maintenance hatch allowing access to the servos in the case of replacement is shown sitting on top of the taped up servo arms.
With the ribs in place, I installed the servos for the inner and outer elevons and put a protective, thin carbon fiber cover over the devices to keep them clean for the rest of the assembly. I used a disc sander to profile the spray foam. The wings weigh 1.3 pounds each. Pretty happy with how they are turning out.
I smeared JB Weld all over the ribs and the leading edge and placed the carbon fiber cover of the airfoil on top, making sure to align the edges carefully. I then used most of my small clamps to make sure this was going to be a good adhesion.
Here's the completed cover. There was still a lot of sanding and filling to be done on the leading edge. I covered the servo arms with tape to protect them during sanding.
Here's a dry assembly of the right wing. You can see the unsanded, but Super-filled leading edge in this photo. The two carbon fiber tubes in the aft of the wing are used to align the wing to the body. The tip of the wing will "tuck" into the wing glove (sometimes called a strake) on the orbiter body.
The final, thick carbon skin of the maintenance hatch allowing access to the servos in the case of replacement is shown sitting on top of the taped up servo arms.
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- Joined
- Feb 9, 2022
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- 294
- Reaction score
- 502
A Quick Weigh In
I threw the wings on as dry assembly and put the payload bay and nose shells on the model. I wanted to get an initial weigh in.
Here's a rear view, with the motor mounts and body flap and the trailing edge of the wings before the elevons are installed.
Side view of the shuttle. It's a 56" long and has a 36" wingspan. Right now, it's 12 pounds. I was aiming for 10 pounds for the whole thing, but I think it will end up around 15 pounds. I expect comments about the weight, so let me get this out ahead of that: I'm building a shuttle that must survive a ride on a level 3 impulse motor - 1 in the External Tank and 2 in SRBs. The Orbiter can contribute if needed with 3 x 36mm motors. It's not just about a gliding recovery. This orbiter will have a landing gear and flight computer. The basic premise is there's way too much going for even a few people to control using traditional RC technology. Still to come: Elevon assembly, vertical stabilizer and rudder, landing gear, working gear doors and avionics. I really am excited to finish this beast. Painting it will be so much fun.
It's my opinion that our hobby will be revolutionized by two things in the next 5 years: propulsive landing (see Joe Barnard at bps.space) and smart software and cheap hardware/sensors for "smart flight" - roll programs and gliding recovery. This project is designed to poke the bear on the second objective.
I threw the wings on as dry assembly and put the payload bay and nose shells on the model. I wanted to get an initial weigh in.
Here's a rear view, with the motor mounts and body flap and the trailing edge of the wings before the elevons are installed.
Side view of the shuttle. It's a 56" long and has a 36" wingspan. Right now, it's 12 pounds. I was aiming for 10 pounds for the whole thing, but I think it will end up around 15 pounds. I expect comments about the weight, so let me get this out ahead of that: I'm building a shuttle that must survive a ride on a level 3 impulse motor - 1 in the External Tank and 2 in SRBs. The Orbiter can contribute if needed with 3 x 36mm motors. It's not just about a gliding recovery. This orbiter will have a landing gear and flight computer. The basic premise is there's way too much going for even a few people to control using traditional RC technology. Still to come: Elevon assembly, vertical stabilizer and rudder, landing gear, working gear doors and avionics. I really am excited to finish this beast. Painting it will be so much fun.
It's my opinion that our hobby will be revolutionized by two things in the next 5 years: propulsive landing (see Joe Barnard at bps.space) and smart software and cheap hardware/sensors for "smart flight" - roll programs and gliding recovery. This project is designed to poke the bear on the second objective.
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