Opinions on 3D Printing, aka Additive Manufacturing

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lakeroadster

When in doubt... build hell-for-stout!
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3D printed rockets. They appear in the "Scratch Build" section and I wonder "Are 3d printed rockets really scratch built"? I would counter they are in reality closer to a manufactured kit.

I'm not an anti technology guy. I embraced CAD/CAM, Solid Modeling, CNC and other such technologies back when I was working as a desinger and these technologies appeared and became mainstream. Huge time and money savings were realized, made perfect sense.

I started my career back in the late 70's, making new designs on a drafting board and working hand in hand with craftsmen, skilled fabricators and machinists who used manual welding techniques and manual lathes. As my career evolved I learned to love these old school technologies and the folks that made manufacturing an art, quickly seeing how it was a world away from throwing a chunk of bar stock in a NC lathe and pushing the "Start" button.

It seems to me that 3d printing is like scanning a photo of the Mona Lisa, printing it on a high end printer, and then taking it to an art gallery and saying "I am an artist, I made this". Well, technically yes you did, but in reality, you didn't, technology did.

Thoughts?

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I have mixed feelings.

But first, an important point: in many of the builds you're referencing, there's quite a bit of design work going into these rockets. They are not simply taking a scan and pushing "print". The difference is, most of the design work is in CAD, and that design work is a much larger percentage of the build than the actual assembly of the rocket itself. But as far as I'm concerned, if the builder is doing the design, then yeah it's scratch built. It's not really different than creating a bunch of vector files and then laser cutting all your parts.

I have designed a few 3D-printed parts for assorted oddball use in my rockets and as jigs, I find it to be extremely fun and satisfying. But for me, the primary enjoyment of building rockets is crafting things things out of wood and paper (mostly). So I haven't been too interested in building stuff that is entirely (or nearly so) 3D-printed. But I also don't own my own printer; maybe if I did I'd be more inclined to use it more aggressively.

I definitely find it interesting to see what folks are doing with it. I particularly enjoyed @hermanjc 's Mandalorian rocket.
 
All of mine are scratch built and take just as much talent to build as “scratch built”. It is more computer skills than the old school hand fabrication but it does take significant talent and experience to get it right.
 
It depends on the process. If you designed/drew the rocket, selected the materials, printed, and assembled yourself, it's scratch built. If you downloaded an stl, then, yeah, not much different than kit building.
 
It seems to me that 3d printing is like scanning a photo of the Mona Lisa, printing it on a high end printer, and then taking it to an art gallery and saying "I am an artist, I made this". Well, technically yes you did, but in reality, you didn't, technology did.

This analogy only applies if you downloaded someone else's stl and printed it. If you digitally designed the part yourself and then printed it, then yes, YOU made it.
 
This analogy only applies if you downloaded someone else's stl and printed it. If you digitally designed the part yourself and then printed it, then yes, YOU made it.

If it's a scratch build design, yes. If you are copying another design... YOU copied it.
 
When I post my scratch built designs that incorporate 3D printed parts I always make sure to indicate if I designed the parts myself or (like in the case of my Mandalorian rocket) I find someone else's design. However, each downloaded file generally requires significant modification in CAD in order to incorporate into a rocket. I.e. the Mando was an action figure model that I had to "assemble" in CAD and then put a hole down through him. My F22 incorporated the nose off someone else's model that I had to modify to slip into twin body tubes, but the rest of the rocket was 100% my design, including 3D printed parts.

I'm most cases these things will be a mix, but unless you are downloading a 3D printable rocket, I think they qualify as scratch built.
 
In general, I would say that trying to pin down the exact line where someone earns the right to call something "scratch built" is unproductive, because it veers into the unpleasant area of judging the validity or worthiness of others' hobby activities.

True story: once I brought a pumpkin pie I had made somewhere (don't remember whether it was work, or a friend gathering, or whatever). Someone asked if it was made from scratch, and I said "yes". Then they asked if I used canned pumpkin, and I said "yes". Then they said "well then it really isn't made from scratch", either out loud or simply with their facial expression, I don't recall exactly. I didn't really respond, although in my imagination I punched them in the face. I also didn't grind my own flour, or churn my own butter from cream I hand-milked from my own cows.

Debating the grey area is pointless IMHO.
 
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It's only "made from scratch" if you carve it from a tree that you grew from a seed, right? :)

I have used various tools to make parts for many years. CNC isn't new and while 3D printing has only recently become common, I don't see a large discontinuity.

This reminds me of the "what is art" discussions, so I agree with Neil here.
 
It seems to me that 3d printing is like scanning a photo of the Mona Lisa, printing it on a high end printer, and then taking it to an art gallery and saying "I am an artist, I made this". Well, technically yes you did, but in reality, you didn't, technology did.

Thoughts?
What if you draw the Mona Lisa yourself, and then scan it?

Scratch builing according to me:
  1. Designing and drawing the finished product.
  2. Designing and drawing each part.
  3. Building each part (regardless of what tool is used, be it a chisel, a CNC machine, a robot, or a 3D printer), using the most unprocessed parts you care to deal with. (Should I plant the seed to grow the tree I'll take the wood from? And buy my own wood lot to do it on? Buy my own oil well and refinery to make the oil-based paint I'll use?)
  4. Assembling the built parts into the finished product.

Those are my thoughts!
 
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All of mine are scratch built and take just as much talent to build as “scratch built”. It is more computer skills than the old school hand fabrication but it does take significant talent and experience to get it right.

Interesting. Sure, you're doing the "scratch design" but the "built" portion is being done by your printer, not you.
 
If it's a scratch build design, yes. If you are copying another design... YOU copied it.

Speaking as someone who spent a considerable amount of time translating old paper drawings into CAD at one of my old jobs, you can argue that it's not really "their" creation, but you can't argue that they deserve no credit if they still made the stl file themselves.

The person using a 3D printer also did build the part, he just did it virtually instead of physically. All the 3D printer does is translate what he did virtually into the real world. Sometimes the physical object doesn't quite do what was needed and the person needs to go back and modify the part and repeat the process until he gets it right.

Making a 3D printed rocket definitely takes skill. It's just a different set of skills than those traditional hobbyists use.
 
In general, I would say that trying to pin down the exact line where someone earns the right to call something "scratch built" is unproductive, because it veers into the unpleasant area of judging the validity or worthiness of others' hobby activities.

True story: once I brought a pumpkin pie I had made somewhere (don't remember whether it was work, or a friend gathering, or whatever). Someone asked if it was made from scratch, and I said "yes". Then they asked if I used canned pumpkin, and I said "yes". Then they said "well then it really isn't made from scratch", either out loud or simply with their facial expression, I don't recall exactly. I didn't really respond, although in my imagination I punched them in the face. I also didn't grind my own flour, or churn my own butter from cream I hand-milked from my own cows.

Debating the grey area is pointless IMHO.
 
Speaking as someone who spent a considerable amount of time translating old paper drawings into CAD at one of my old jobs, you can argue that it's not really "their" creation, but you can't argue that they deserve no credit if they still made the stl file themselves.

The person using a 3D printer also did build the part, he just did it virtually instead of physically. All the 3D printer does is translate what he did virtually into the real world. Sometimes the physical object doesn't quite do what was needed and the person needs to go back and modify the part and repeat the process until he gets it right.

Making a 3D printed rocket definitely takes skill. It's just a different set of skills than those traditional hobbyists use.

I agree totally. I'm not debating skill sets, the original question is..

"Are 3d printed rockets really scratch built"?
 
Interesting. Sure, you're doing the "scratch design" but the "built" portion is being done by your printer, not you.

No true. I am not sure what designs you have looked at. Many of mine take skill to get the part designed and to adhere to the tubing.
 
It's only "made from scratch" if you carve it from a tree that you grew from a seed, right? :)

and you made the knife from steel you smelted using a furnace you built and ore you dug...

There's a great Nova episode from years ago showing the traditional Japanese methods of steel-smelting and sword-making, where one master sword-maker basically does the whole thing from ore to katana.
 
No true. I am not sure what designs you have looked at. Many of mine take skill to get the part designed and to adhere to the tubing.

This thread is not directed at anyone or any specific rocket. It is in ref. to 3d printed rockets.

Should a rocket that is mostly built from 3d printed components be considered scratch built?
 
This thread is not directed at anyone or any specific rocket. It is in ref. to 3d printed rockets.

Should a rocket that is mostly built from 3d printed components be considered scratch built?

In my opinion, yes, but I accept that some people would argue the opposite and that wouldn't offend me either. I tend to agree that downloading stl's or similar of a rocket would be less scratch built, I would also be OK with downloading greebles and attaching them to the rocket for sure.

I think certain members show amazing traditional craftsmanship skills (the late Micromeister is a perfect example, IMO, but there are lots of others too). I also think that a person who designed a rocket completely in RockSIM (or CAD/whatever) and then bought a bunch of custom parts from a vendor and assembled them is a scratch build, but one could say the craftsmanship is less in that case. I don't agree, as the assembly process exhibits certain craftsmanship skills, even if the nosecone wasn't turned on their own lathe or the fins came off someone else's laser. The build/finishing aspect still counts as craftsmanship.

The skillset for doing 3D printing (or CNC V-Carving, manual turning, hand carving) all exhibit craftsmanship, just different skillsets.

Personally, I would consider any one-off custom design a scratch build, but I would also consider a copy of an existing design done by the builder as a scratch build. I could understand if the Scale model/contest community would possibly make some tweaks to rules due to 3D printing, but until we reach 100 million active scale modelers in rocketry, I don't know that more rules would be worth the effort.

Interesting question (especially since I have generally shied away from 3D printing, even though I own a resin printer), but I enjoy seeing the creativity from people's heads getting made and if 3D printing is moving the ball forward for more exotic rockets for me to see, I'm all for it.

Sandy.
 
If I design the rocket from scratch, it's a scratch build regardless how the parts are made. I don't wind my own tubes or make my own plywood. When I create the program to CNC/LC fins that is no less technical than cutting them on a table saw. I feel the same is true for parts I 3d print on my mk3s, except I actually own and maintain it vs the CNC I pay someone to run or the laser cutter I borrow time on. Designing the rocket is the skilled portion related to the hobby. Part creation and to a lesser degree assembly are incidental. Just my two cents...
 
I don't really think it needs to be defined but I will add my thoughts...

FWIW - "Scratch building is the process of building a scale model "from scratch", i.e. from raw materials, rather than building it from a commercial kit, kitbashing or buying it pre-assembled." -- https://en.wikipedia.org/wiki/Scratch_building (figured it might be good to see a definition from somewhere)

Thread from 2012 in an RC plane forum suggests that this has been an argument for a long time...
https://www.rcgroups.com/forums/showthread.php?1669038-What-does-Scratchbuilt-really-mean
Someone posted much of this in that tread but I added kit-bashing to it as well as comments in parenthesis:
  • Scratch-building - building from your own plans, making your own parts (no rules about how you make parts or what level is considered "raw" materials -- I like the Sagan video, we are all using manufactured parts at some level)
  • Plan-building - building from somebody else's plan, making your own parts (I am not sure if this is / needs to be a level and I have never heard this term but it was in the original post. There is a gray area between adapting plans to work as a model rocket plan vs. just following someone's directions to build to their plan -- for example, anyone who tries to do scale/semi-scale is copying the prototype so could arguably be working from someone else's plans. However, even the Wikipedia article indicates that scratch building is often done from the plans for the original or from measuring pictures of the original)
  • Kit-bashing - building from your own plans, using parts from manufactured kits (again could overlap with much or most of the scratch-building definition since many people are using kit parts to scratch-build).
  • Kit-building - building somebody else's design from prepared parts
  • Assembling - putting together an ARF
Obviously, I am one of the ones posting a number of 3D designed / printed rockets in the "Scratch Build" area. I thought about posting these in the "Scale Builds" forum but figured my stuff is semi-scale at best. In all of my rockets posted there I am designing the parts and overall model myself from photographs or plans of the original, printing, and assembling the models (almost always cutting fins from 2mm basswood and using standard sized body tubes - and making designs fit these constraints).
 
This thread is not directed at anyone or any specific rocket. It is in ref. to 3d printed rockets.

Should a rocket that is mostly built from 3d printed components be considered scratch built?

I understand that but absolute statements are often wrong. Most 3D-printed rockets still that a significant amount of assembly and some take as much skill and effort as the most intricate designs placed on the forum. I am not talking about the Thingiverse downloads.
 
Should a rocket that is mostly built from 3d printed components be considered scratch built?

How is:
additive manufacturing with a 3D printer,
any different than:
subtractive manufacturing with a CNC machine
?

Would you consider a part built from a blank and a CNC machine as scratch-built?
 
How is:
additive manufacturing with a 3D printer,
any different than:
subtractive manufacturing with a CNC machine
?

Would you consider a part built from a blank and a CNC machine as scratch-built?

Scratch built by who?

The Laborer who put the chunk of steel into the machine?
The Programmer that turned the CAD file into the CNC program?
or
The designer that designed the part?

No, it's not any different.

IMO, none of what you are describing is scratch built.
 
I would indeed call the laborer, programmer and designer(s) "buliders" (and maybe even those who designed the CNC machine and its software), and I would see the CNC machine as a very elabrate "chisel" (or tool). I understand what you're saying and maybe there's a difference to be seen between "hand-built" and "machine-built". But either way, if the starting materials are basic geometrical shapes or "stuff found lying around", I would say it qualifies as "scratch".

My question would be where to draw the line between a hand-chisel, a powered lathe, and a CNC machine. One could have many levels of options between a powered lathe and a CNC machine. It's really just 1 motor vs many motors, 1 command vs a sequence of commands, 1 blade vs many different blades, etc.
 
I think this comes down to an old vs new way argument. I am an electronics tech and in no way any sort of Luddite, but I personally find time hand building something more satisfying.
In the past, I used an example of a stick built Mercury Redstone escape tower vs a 3d printed one. Are they the same? Yes and No. To misquote Spock: "Different skill sets, Captain. Totally, completely, and absolutely different skill-sets."

As far as high power, HPR = anything goes to me and is about making it work.

In the world of contests is where the split is. I think both methods should be honored but separated into categories. Best Scale / Best Sport Scale with a manual and 3d printed category. Makes sense based on the Spock misquote and only requires a couple different ribbons.

Cheers / Robert
 
I understand that but absolute statements are often wrong. Most 3D-printed rockets still that a significant amount of assembly and some take as much skill and effort as the most intricate designs placed on the forum. I am not talking about the Thingiverse downloads.

Once again, skill is not the topic. Defining what "Scratch Built" is, that is the topic.

I would indeed call the laborer, programmer and designer(s) "buliders" (and maybe even those who designed the CNC machine and its software), and I would see the CNC machine as a very elabrate "chisel" (or tool). I understand what you're saying and maybe there's a difference to be seen between "hand-built" and "machine-built". But either way, if the starting materials are basic geometrical shapes or "stuff found lying around", I would say it qualifies as "scratch".

Yep, that's great and makes a lot of sense. Hand Built vs Machine Built.

....... I think both methods should be honored but separated into categories. ... a manual and 3d printed category.

Cheers / Robert

I would counter, not just for contests, also as forums.

Logic.jpg
 
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In the world of contests is where the split is. I think both methods should be honored but separated into categories. Best Scale / Best Sport Scale with a manual and 3d printed category.
Presumably you will then need to define exactly what percentage of the rocket (by weight? Volume? Surface area?) is 3D printed in order to select the appropriate category.

Where do you imagine that cutoff would be?
Yep, that's great and makes a lot of sense. Hand Built vs Machine Built.

I would counter, not just for contests, also as forums.
Is *that* where you’re going with this? You don’t want 3d printed or CNC machined rockets in the scratch built forum? Where do laser cutters come in?
 
I'm not worried about the forum nor the contests. Just seemed an easy way to fix a split, let the NAR award 3 more ribbons for the above contests, have more entries and winners, and spread happiness and love throughout the world : )



Cheers / Robert
 
Is *that* where you’re going with this? You don’t want 3d printed or CNC machined rockets in the scratch built forum? Where do laser cutters come in?

Can you build a complete rocket, nose cone to fins, on a laser cutter? Then insert a motor, a parachute and launch it? Nope.

Take a deep breath... and ponder... if you 3d print a complete rocket (except for parachute and motor) again, I ask.

3D printed rockets. They appear in the "Scratch Build" section and I wonder "Are 3d printed rockets really scratch built"?
 
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