How many of you CAD your rocket?

[Yukon@K-9 Rocket Tech]

I always CAD all my rockets before I start building in F360. Just wondering, how many of you do this?

 

[Nytrunner]

I rarely make solid models of my rockets since OpenRocket makes an image (albeit low fidelity) and has the added simulation features to boot. CAD for individual pieces and assemblies takes time, and my time is money. I spend enough money on the hobby already.

I primarily make boilerplate single piece models for running CFD cases on when I need a better CP estimate than OR can provide. (see snip from working on my L2 rocket)

If I'm actually designing a part to be 3D printed or fabricated, I'll model the relevant section of the rocket as necessary to make sure things fit.

A notable exception for me was the Estes Pro Series Patriot. For some reason I got the bug to measure, document, model, and produce a drawing packet for it. Probably because of the unique design elements present in an OoP kit.

You seem to 3D print everything except your tubes, so for your case you kinda have to model everything before fabrication. Sworn of the ol plywood and plastic cones eh? Your rockets could be a whole lot lighter!

 

[K'Tesh]

Not quite that level... but I do use OR for them...

 

[Yukon@K-9 Rocket Tech]

I rarely make solid models of my rockets since OpenRocket makes an image (albeit low fidelity) and has the added simulation features to boot. CAD for individual pieces and assemblies takes time, and my time is money. I spend enough money on the hobby already.

I primarily make boilerplate single piece models for running CFD cases on when I need a better CP estimate than OR can provide. (see snip from working on my L2 rocket)

If I'm actually designing a part to be 3D printed or fabricated, I'll model the relevant section of the rocket as necessary to make sure things fit.

A notable exception for me was the Estes Pro Series Patriot. For some reason I got the bug to measure, document, model, and produce a drawing packet for it. Probably because of the unique design elements present in an OoP kit.

You seem to 3D print everything except your tubes, so for your case you kinda have to model everything before fabrication. Sworn of the ol plywood and plastic cones eh? Your rockets could be a whole lot lighter!

View attachment 416201

Gotcha! Very practical! Lol yup I kind of over 3D print stuff so gotta CAD. I guess with your sort of hybrid approach that's very practical. I personally found the time in CAD to cost me less money in the end because I don't have to redo parts that I found out wouldn't work. But that's just in my case. What CFD do you use? That pic from the sim is pretty Awesome! I want to get more into CFD but only played around with free trials

 

[Nytrunner]

I personally found the time in CAD to cost me less money in the end because I don't have to redo parts that I found out wouldn't work.

When it comes to fabricating parts, this is absolutely correct.

What CFD do you use? That pic from the sim is pretty Awesome! I want to get more into CFD but only played around with free trials

I have an old copy of Solidworks 15 and use the Flow-Sim toolbox that comes along with it.
For CFD to actually be useful, you'll need to study up on fluid mechanics and dynamics. Otherwise you're just copying what people do in youtube videos and lose the fundamental understanding.

 

[Yukon@K-9 Rocket Tech]

When it comes to fabricating parts, this is absolutely correct.



I have an old copy of Solidworks 15 and use the Flow-Sim toolbox that comes along with it.
For CFD to actually be useful, you'll need to study up on fluid mechanics and dynamics. Otherwise you're just copying what people do in youtube videos and lose the fundamental understanding.

Gotcha, I should know what I'm doing in it and not blindly type in parameters and numbers that I have no Idea what they mean. Stuffs way over my head for now but can't wait to learn in the future. Guess I'll stick with the load cell and fogger since drag and suoer basic airflow is all I care about now

 

[swatkat]

I just use the good ol' open rocket to build all mine for sims' sake. if I need to 3D print a part, then I'll cad.

 

[Scrapmaster87]

I do my high level design in open rocket, but the details get done in cad.

Here's my current build in design now, I may be rolling the motor tubes this or next week. It's for a Big Bertha upscale, I'm planning on using the tool-less e-bay I prototyped on my last build. Body will be 4.6" dia with 1x 38mm and 4x 29mm mounts.

It'll be my first:
explicit level 2 build
composite cluster build
air-start capable build (can fire 2x sets)
dual altimeter build (eggtimer proton + quark)
over 10 lbs?

 

[David Schwantz]

How do I put a hole in my object in Fusion 360? Trying to make a hole to accept a LOC mmt tube.

 

[dr wogz]

Good for you!

start taking advantage of equations / relations in CAD. Make it so your tube is always X times the length, or that a hole is always centered: d2=d1/2.

Start also looking at skeletal assemblies, can be quite powerful, or parts / assemblies driven from a spreadsheet. You should be able to make your parts / assemblies truly parametric, and be driven by only 3 or 4 data inputs. (I worked in one place, where we made hydraulic cylinders. The whole model was driven by 3 or 4 inputs: Dia, Stroke length, and [can't remember]. Everything else feel into place, drawings were automatically generated (yeah, the odd one needed tweaking, but most of the work was done) Practice drafting & making drawings. Littering a drawing with dimensions doesn't make it manufacturer, but placing the right dimension in the right place makes it so.

I'm a Creo & Inventor guy, and have been since Autodesk Mechanical Desktop V1! I do some part in CAD just to get an STL file for the printer..

 

[dr wogz]

Oh, and get really good at using work planes, points & axis. this will help you create & assemble things easily in the future!

 

[lakeroadster]

Neat idea for a thread

I typically start the design using Open Rocket, then create models and a drawing package using Autodesk Inventor.

Then during the build process update OR and Inventor files as the build progresses.

 

[cwbullet]

Very nice products.

 

[Nytrunner]

Oh, and get really good at using work planes, points & axis. this will help you create & assemble things easily in the future!

+1 for reference geometry

 

[boatgeek]

I'm in the "when I have to" camp as well. Obviously yes for 3-D printed stuff and when I was getting things laser-cut by a friend. No for nose cones, tubes, and other standard parts other than what OpenRocket does (technically Computer Aided Design ). Gray areas are things like parachute panels and the like. If there are curves, I generally CAD them out to get exact dimensions. If they're smaller pieces or rectangular, I don't tend to.

Oh, and I CAD my quilts both for piece patterns and for layout of the pieces on the fabric stock. Saves material if you can pack it closer. I also use a quilting service with a NC-controlled sewing machine, so I can do custom stitch patterns. That lets you get a LEM on your Apollo 11 quilt.

 

[dr wogz]

K-9, another skill to practice / master is hand sketching; both isometric & orthographic. Time is money, and you boss / lead designer / project manager won't give you the time to 'concept' your ideas in CAD. If you can generate your idea / intent with pencil & paper, and show what you want, that saves time, moves the design process along quickly, and you can start to see things more clearly than when you are deep in 'CAD model mode'. You can also start working out a lot of the math (fits & clearances) as you sketch things out.. CAD then also becomes quicker, as you're just transposing your idea from paper to virtual space with a lot of the work already done.

 

[boatgeek]

K-9, another skill to practice / master is hand sketching; both isometric & orthographic. Time is money, and you boss / lead designer / project manager won't give you the time to 'concept' your ideas in CAD. If you can generate your idea / intent with pencil & paper, and show what you want, that saves time, moves the design process along quickly, and you can start to see things more clearly than when you are deep in 'CAD model mode'. You can also start working out a lot of the math (fits & clearances) as you sketch things out.. CAD then also becomes quicker, as you're just transposing your idea from paper to virtual space with a lot of the work already done.

+1 Also, a sketch is often enough for a dedicated CAD operator to turn out a drawing. That usually saves money because CAD monkeys tend to be cheaper than engineer monkeys. They're usually a lot faster at CAD work than engieners, so it's a double benefit to the company. Not all companies work that way, but many do. Finally, work on using blocks and other references so you can develop a library of parts that you can drop into the drawing you're working on. That almost always saves time.

 

[Yukon@K-9 Rocket Tech]

I do my high level design in open rocket, but the details get done in cad.

Here's my current build in design now, I may be rolling the motor tubes this or next week. It's for a Big Bertha upscale, I'm planning on using the tool-less e-bay I prototyped on my last build. Body will be 4.6" dia with 1x 38mm and 4x 29mm mounts.

It'll be my first:
explicit level 2 build
composite cluster build
air-start capable build (can fire 2x sets)
dual altimeter build (eggtimer proton + quark)
over 10 lbs?

I like your models

 

[Yukon@K-9 Rocket Tech]

K-9, another skill to practice / master is hand sketching; both isometric & orthographic. Time is money, and you boss / lead designer / project manager won't give you the time to 'concept' your ideas in CAD. If you can generate your idea / intent with pencil & paper, and show what you want, that saves time, moves the design process along quickly, and you can start to see things more clearly than when you are deep in 'CAD model mode'. You can also start working out a lot of the math (fits & clearances) as you sketch things out.. CAD then also becomes quicker, as you're just transposing your idea from paper to virtual space with a lot of the work already done.

Gotcha! Thank you so much for all your tips! Yes I'm used to just getting on my computer and "conceptualizing" straight on CAD. Guess I better start sketching and start learning more geometry

 

[Yukon@K-9 Rocket Tech]

I'm in the "when I have to" camp as well. Obviously yes for 3-D printed stuff and when I was getting things laser-cut by a friend. No for nose cones, tubes, and other standard parts other than what OpenRocket does (technically Computer Aided Design ). Gray areas are things like parachute panels and the like. If there are curves, I generally CAD them out to get exact dimensions. If they're smaller pieces or rectangular, I don't tend to.

Oh, and I CAD my quilts both for piece patterns and for layout of the pieces on the fabric stock. Saves material if you can pack it closer. I also use a quilting service with a NC-controlled sewing machine, so I can do custom stitch patterns. That lets you get a LEM on your Apollo 11 quilt.

View attachment 416341 View attachment 416342

Nice quilts! Also your right, Open Rocket is technically Computer Aided design lol

 

[JoePfeiffer]

Everything goes through OpenRocket; 3d printed parts are modeled using Python and the PythonOCC bindings for opencascade.

 

[jqavins]

I 3D CAD as little as possible. I use RockSim and occasionally MS Visio for 2D, and OpenSCAD for 3D when it can't be avoided. Because my 3D CAD chops are virtually nonexistent.

Visio is sufficient for laser cutting patterns and sketches. (My hand sketches look like they were done by a six year old.) Once I did a detailed internal layout with it. OpenSCAD is for 3D printed parts, and I've only had to do it once. That was for the nose cone on my elliptical rocket, and I did complete the body tube and fins under it just to make sure it all looked right together.

 

[new2hpr]

+1 Also, a sketch is often enough for a dedicated CAD operator to turn out a drawing. That usually saves money because CAD monkeys tend to be cheaper than engineer monkeys. They're usually a lot faster at CAD work than engieners, so it's a double benefit to the company. Not all companies work that way, but many do. Finally, work on using blocks and other references so you can develop a library of parts that you can drop into the drawing you're working on. That almost always saves time.

More and more, I'm seeing companies (at least the ones I've been in), moving towards having their engineers do all their own CAD work, leaving the 'Mechanical Designers' out on the street. Their (management) thought process is 'CAD has gotten so easy and fast that we don't need dedicated people for it. The Engineers can do that in their extra time.'

I definitely agree that the CAD designers are MUCH faster than engineers at that type of work. I'm good friends with several who have only been able to hang on to their (no Engineer degree) job because they are SO much more productive. One guy got pulled immediately into an in-person interview after 'scoring the highest they've ever seen' on a practical CAD screening test (Pro-E/Creo). Had the job the next day. Skills and speed =$ to companies.

 

[Zertyme]

I CAD a lot. Nearly all of my rocket went through Fusion360. Once I have the overall design in Openrocket, I switch to Fusion360 then RasAero.
I also render them, here's an example: "Running in the 90's"; N5800 to M2245, more detail on the Australian Rocketry Forum.

 

[Yukon@K-9 Rocket Tech]

I CAD a lot. Nearly all of my rocket went through Fusion360. Once I have the overall design in Openrocket, I switch to Fusion360 then RasAero.
I also render them, here's an example: "Running in the 90's"; N5800 to M2245, more detail on the Australian Rocketry Forum. View attachment 416864
View attachment 416861

Dang nice renders!

 

[bobby_hamill]

Been using CAD for 3d parts and decal wraps .
It is a long way off but even working on a functional cable elevated
Black Brant 2 launcher used at Wallops

 

[bobby_hamill]

Also I used CAD for my SparoAir 2 model
The 3d fin cans were printed by cwbullet