MX-774 3D Scale Build

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Leo

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The MX-774 has always interested me because it uses 4 rocket motors for propulsion.
The version I'm designing is going to be the last flight it had, lengthened version.
Scale data is very scarce. I'll be using many picture stills from captured videos.

I've decided to design a version that can be 3D printed on an Ender-3 size printer.
It will use BT-80 size tubes for the main air frame. The rest will consist of 3D printed parts.
I want to fly the rocket with 4 x 18mm (in my case D9-P) motors and use dual deploy recovery.


Here the first mockup of the parts:
MX-774_Complete_1_Leo.jpg


First step will be to design the fin can. It will be one complete piece for printing.
MX-774_FinCan_1_Leo.jpg

Missing are more rivets, antenna's and hatches.......

I'm documenting the progress here as an overview. We'll see how long this will take....
 

Funkworks

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I like the MX-774 because it looks a lot like a V-2. It's like they wanted to designed a new rocket from scratch but played it safe and kept much of a tested design.
 

rharshberger

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Looks nice Leo! By the way thanks for posting your Nike Smoke .stl's to Thingiverse and here, I have them download but not yet printed.
 

Leo

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Rich,

I strongly recommend not to download the files from Thingiverse but rather save the links of the page. Only download the files when you are actually intending to print the parts. Many times modifications are made to the files.

I'm surprised that so few people have printed my Nike variants. I'm starting to get the feeling the designs are too much of a challenge for most. I hope you post your results. Let me know if you have any problems.

I'm looking into maybe designing the MX-774 fin can in to separate parts, similar to a Nike Smoke version I did.
 

rharshberger

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Thanks Leo, I am currently waiting on a new BL Touch pin for my printer (touch pin broke, and new one is coming from Texas) as well as a new roll of petg which wont arrive until the 24th thanks to Amazon's prioritizing.
 

Leo

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I'm going to call the fin can done. One can always add more details when needed.
FinCan_4.png
 

Leo

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Today I decided to see what would happen if I downscaled the fin can to fit an Estes BT-60. Quick scale calculation and off it went to the printer. While the printer was running I went ahead and designed the nose cone in CAD. After the fin can was done I sent the nose cone to the 3D printer.

I must admit the parts turned out great. Looked and found a spare body tube, cut it to length and put the parts together.

MX-774_Complete_1.jpg
MX-774_Nose_Cone_1.jpg
MX-774_Fin_Can_1.jpg


It was here when I realized that the original rocket only had 2 of the 4 small fins move for flight corrections so I will have to correct that.
Both cable shrouds also need to be made. I will be 3D printing these as well.
 

Ez2cDave

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Today I decided to see what would happen if I downscaled the fin can to fit an Estes BT-60. Quick scale calculation and off it went to the printer. While the printer was running I went ahead and designed the nose cone in CAD. After the fin can was done I sent the nose cone to the 3D printer.

I must admit the parts turned out great. Looked and found a spare body tube, cut it to length and put the parts together.
Leo,

It may just be the angle, but the BT-60 version looks "over-length" to me.

The MX-773 was 31',7" ( 379" ) in length and 30" in diameter.

Using a BT-60 ( 1.637" diameter ) makes it a 1:18.326206 scale model, which should have an overall length of 20.68" . . .

How long is the model in the photo's ?

Dave F.
 

Leo

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I'm building round 3 as stated in my first post. It had an elongated instrument compartment.
My finished model as shown is 541mm (21.3") in length. I think that should be correct.
 
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Ez2cDave

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I'm building round 3 as stated in my first post. It had an elongated instrument compartment.
My finished model as shown is 541mm (21.3") in length. I think that should be correct.
I missed that . . . Looks like we were both right - LOL !
 

beeblebrox

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Today I decided to see what would happen if I downscaled the fin can to fit an Estes BT-60. Quick scale calculation and off it went to the printer. While the printer was running I went ahead and designed the nose cone in CAD. After the fin can was done I sent the nose cone to the 3D printer.

I must admit the parts turned out great. Looked and found a spare body tube, cut it to length and put the parts together.

View attachment 412762View attachment 412763View attachment 412764

It was here when I realized that the original rocket only had 2 of the 4 small fins move for flight corrections so I will have to correct that.
Both cable shrouds also need to be made. I will be 3D printing these as well.
Loved your Nike Smoke...Now I have to inject this project into my long list of projects I can't do because I need to manufacture a Time machine to fit it all in...lol

Any chance of an inter-stage and Tomahawk to go with the Nike??? ...Please... and thank you in advance... Or if you (Or anyone else reading this) has scale plans for the Nike-Tomahawk, please post.
 

Ez2cDave

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Loved your Nike Smoke...Now I have to inject this project into my long list of projects I can't do because I need to manufacture a Time machine to fit it all in...lol

Any chance of an inter-stage and Tomahawk to go with the Nike??? ...Please... and thank you in advance... Or if you (Or anyone else reading this) has scale plans for the Nike-Tomahawk, please post.
Oh, yeah . . . I speak "Nike-Tomahawk" - LOL !

Here is the Interstage * Fin Support Unit . . .

Shoot me an email, if you need other data : Ez2cDave@aol.com

Dave F.

ART-ROSE-TOMAHAWK-INTERSTAGE.jpg



FIN SUPPORT UNIT - 1.JPG



NIKE-TOMAHAWK DATA001.jpg



NIKE-TOMAHAWK DATA002.jpg
 
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