Ask HN: Resources for “Learning” Manufacturing?
I have been learning cad with fusion360, and have already designed, fabricated and built a number of small items for my own (personal) use around the farm. To date, this has meant prototyping with the 3d printer, outsourcing laser cutting of steel (up to 10mm thickness) and welding parts by hand. Its been mainly small tractor attachments/brackets/etc.
I am becoming a bit more adventurous with my designs, and have started designing some ideas that would need to be injection moulded to be of any real practical use. There are also some aspects of the design that I believe would need to be rotomoulded to reduce material usage and weight to acceptable levels.
How can I move to this "next level" of prototyping and small scale manufacture? Is this something I can achieve myself with (limited) investment in specific machinery (budget ~15k USD)? Im only looking at small runs - but a number of parts, which I would assume would make more commercial offerings expensive?
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[ 3.1 ms ] story [ 222 ms ] threadThat said, contract manufacturers are easy to work with. They'll do the mold design based on your CAD model of the object. Making the molds is the most expensive part.
Without knowing the specifics of your part. Usually you can trade a more expensive process and still get a workable prototype part if you want to avoid molding. Eg, commercial 3d printing, (assemble panels together for larger parts), cnc milling.
Do you have a validated market for your product? If you don’t want to do the equipment purchase upfront but can demonstrate that your are a competent client, a contract manufacturer would be able to help you with the smaller first runs.
https://lcamtuf.coredump.cx/gcnc/
Maybe opening a small lab for youngsters, schools and happy triggers in your neighborood? You would personally benefit from new, like-minded acquaintances while keeping your running costs covered and surveying business opportunities.
Terminology is important.
Manufacturing is usually outlined by Industrial Systems Engineering for setting-up assembly lines.
Design for Manufacturing (DfM) is an engineering approach to reducing costs and manufacturing complexity of products.
These comprise different areas of responsibilities.
There is no single, universal answer but there are important questions to consider. At what scale? What are you making? What is the current cost per unit? What is the cost per unit target? How much would it cost to build it using powder-sintered FDM?
"Real" MEs use Fusion 360 as well, and it can do all the buzzwords he mentioned.
There is something wrong with dissing "buzzwords" you don't understand.
When you have something useful to say and a better attitude, then dialogue maybe possible. But until then, have a better day.
You said Fusion is for amateurs, and that "real" MEs don't use it. That's wrong, plenty of real MEs use it. You then listed a bunch of features that Fusion 360 actually has in a way suggesting it doesn't.
You also used a bunch of terms and pointed towards the importance of knowing those terms - which is just another form of gatekeeping. You didn't mention them in a way that suggested them as useful search terms to research.
And now you are saying I don't understand your buzzwords. Well, I do. Now what?
My attitude is simple: provide op with something that helps and encourages him. Telling him his tool is amateurish and throwing around some ME terms doesn't achieve that.
I would argue CAD/CAM packages are the same. While there’s absolutely nothing wrong with fusion360 (I use it to for persona use too), it is true how the market penetration is extremely slim. Even the industrial sibling Inventor has only a small percentage of the market. While a lot of it is historical reasons, there are good reasons why most small to medium sized companies use Inventor/Solidworks and MasterCAM as their main driver.
I started with pen and paper and had to do the 3d part in my head, and working out the material resistance calculations with equations, no fancy finite elements...for context.
There is a russian one also, but I don't know the status. Or if it is only a kernel like opencascade.
The problem is the tool cost vs. small production runs. Plus, designing good tools can get really tricky.
Here is what I would do on the garage scale:
* A CNC router like shapeoko or x-carve (you can buy or diy)
* This allows you to build large, but rather flat moulds
* Pouring epoxy resin mixed with e.g. cotton flakes or other additives gives you nice solid objects
* Laminating glass or carbon fiber can net you large surfaces
* Vacuum forming also nets you large surfaces and can be done with a diy machine
Old, used machines are also always a good idea.
You're going to have to be specific as it is entirely up to what you are manufacturing. How tight are your tolerances? Is it plastics? Metals? By small scale do you mean a batch of 10, 100, 1k, 10k?
There are first class machinists on YouTube that will teach for free and to be frank, I've yet to run into anything that couldn't be machined with a bit of skill, a lathe, a drill press, and a milling machine, all of which you can pick up on the cheap. I'd start there. What about it makes you need to use injection molding? That's a process used in bulk production. If it's tractor brackets and such then casting might be a better idea. If you're looking into injection molding, you'll have to get in contact with professionals - the tooling is in the range of hundreds of thousands if not millions. The "next level" of prototyping for you I think would be machining, not IM. You might be able to pay a contractor to do IM for you but it'd be a stretch at your budget.
On a tangential note, I'm currently working my way through MIT's "Principles of Manufacturing" MicroMasters program on edx and would thoroughly recommend it. It's more large scale systems then anything, but it's been great for me in terms of learning the vernacular and has helped me better communicate with manufacturers when I'm looking to scale one of my designs. Might be worth checking out.
https://courses.edx.org/dashboard/programs/452d5bbb-00a4-4cc...
A lot of manufacturing knowledge seems to be "oral culture". Finding a local contract manufacture firm to partner with might be a good next step.
Edit: And also there's a textbook which covers pretty much every method of making things:
Kalpakjian, S. Manufacturing Engineering and Technology.
I agree with the other points, injection molding would be difficult to get into and is designed for moderately big runs. That being said, I know of a guy who was in a similar position as you with a couple inventions he wanted to bring to market. The quote for plastic injection molds was coming out to low 6 figures, and there wasn't a guarantee they would work the first try, so he bought a 3-axis CNC mill and a plastic injection molding machine for the same cost and could iterate faster and cheaper. He now runs a decent size contract manufacturer in Iowa.
Depending on your designs and interests, I'd suggest checking if your nearby community college has welding classes. They're typically very cheap and professional guidance with a skill like that is invaluable. They may have other classes for other manufacturing skills which you could learn on YouTube, but again professional guidance can be invaluable for learning fast and avoiding poor habits that will hold you back later.
Take a look at the hobby offerings for Inventor and Autodesk if you feel at all limited. I recently tried using Fusion 360 but found the interface confusing coming from using Autodesk in school.
If you have more specific examples of things you're looking to make, we could give more tailored advice. There are tons of manufacturing processes available, each with a range of units and product features they're optimal for.
Back in school the manufacturing professors would have us bring in products if we couldn't determine the manufacturing method and they would help us figure it out.
For small parts, it’s now possible to buy reasonably priced injection molding machines (under $10K) that take 3D-printed (resin, not FDM) molds.
This is the way to learn and iterate. Mold making is not as easy as it sounds, but it can be learned. Once the mold is working well you can CNC machine a soft or hard tool.
Although I have to admit that even in the large scale manufacturing space we have no desire to do injection molding in house. Working with a trusted Chinese injection molding company is extremely cheap these days.
They're also very new, so they're not as mature as old machines. Older machines are massive and poorly documented, though.
This is one of the more polished micro injection machines: https://www.micro-molder.com/
This one is more industrial but seems better for continuous runs: https://www.apsx.com/desktop-injection-molding-machine
There are also several Chinese vendors offering reasonably priced injection molding machines now, but unless you're well-versed in the art of dealing with these vendors and DIYing your own support, they're not a great place to start.
If you just want to experiment, you can build or buy a manual lever-operated machine for under $500: https://busterbeagle3d.square.site/product/buster-beagle-3d-... These won't be powering any production runs, but if you're only interested in prototyping then they can be surprisingly effective.
FWIW I found the same nonsense when doing schematic and PCB layout with e.g. Eagle. I'm running a data bus from one component to another. This is a standard thing since the 70s. Why is the tool making me drag lines and manually connect them and individually label them? In Eagle get the exact mouse end point wrong and it doesn't even connect the components and you don't find out until much later in the process when you move something or try to switch to PCB layout and nothing hooks up. Yes, there's some aggregate bus routing stuff but it's the exception rather than the rule.
I don't understand how hardware and manufacturing engineers can stand these tools. So manual and finicky.
I tried some of the programmatic CAD tooling, too but they also didn't really click with me. But I did notice a plugin for Fusion 360 that adds python scripting, so I might give that a try.
I find F360 to be quite efficient and precise at these things.
Make a sketch; make a rectangle. Constrain it until it all turns black (do this by reference to the origin). Drop a circle on the sketch. Click the circumference. Press d. Place the dimension tag. Enter the diameter. Press d again, click the center of the circle. Click the left edge of the rect, drag the mouse up to place the tag someplace nice. Type in the distance from the edge to the center of the circle. Do the same for the Y location.
It shouldn’t feel like you’re dragging and sizing anything manually unless it’s just a decorative part.
I will say that I learned a lot by watching James at clough42 do some designs, but I think I’d learned the very basics before that.
Briefly, for functional parts: “blue lines on the sketch are bad” Add constraints until they turn black (fully constrained). If you aren’t sure why a line is blue, drag it and see which degree(s) of freedom it still has and add constraints to those.
Once you have that down and made a drawing, I’d then look at “modify user parameters” to make sketches more easily tweakable (especially if you’re 3D printing or trying to match a bolt pattern that’s somewhat “random”). Almost every drawing I start now starts with defining the user parameters (and then using those as the dimension entries).
This might not be the best “first video” to watch, but it’s topically relevant to help you here: https://clough42.com/2020/07/04/tap-guide-block-ii-fusion-36...
I use Fusion 360 exactly how you say you want to. Just slap some shit on there and then use dimensions and constraints to actually precisely position everything to match my measurements.
Parametric modeling is a godsend for woodworking.
Even with aluminum molds at a low cost focused prototyping CM, which are MUCH cheaper than steel molds, I think the pricing for just one set of tooling is going to exceed your $15k budget.
Finding 3D printing contract manufacturers who can manufacture with the materials you're interested in would be my recommendation if you're moving into plastics. The unit cost is going to be extreme compared to injection molding, but there's almost 0 tooling cost, so for prototyping 1 or 2 units will be significantly cheaper. Advanced 3d printing these days can rival (or even exceed) the performance of an injection molded part.
It really depends on where you go. I've got vendors in China that could easily do 2 dual cavity production tools in that budget.
Depending on the size and complexity of your part might just make it for $15k to get the tooling done. The manufacturing itself most probably will never make sense to do inhouse.
It appears the company may be defunct, but the information is pretty good.
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Edit: It looks like they were acquired - https://ir.avnet.com/news-releases/news-release-details/avne...
Personally, the biggest hurdle for me is "finding" the cost of some of these processes so that I could adapt my idea and material early on. All places in my local area require you to submit a formal quote and plans without giving you an indication at all of how much it'll cost (which is inside info that people who use those services often know).
Oh and don't get sucked into the trap of ordering runs from Alibaba, even though you will find someone that does what you need at a cheap price there. It's a pit of time sifting through spam and incorrect info till you find a good reliable supplier, so rather deal with local providers in your area.
Not convinced it's the best, as I didn't really enjoy the class, but that was mostly due to a poor lecturer. I'm also not convinced that it's the most relevant for you, as you seem to be looking more into "small batch prototyping", rather than mass scale manufacturing.
Still, it's a good book for getting an overview of what is out there in terms of processes and figuring out what would be appropriate for your needs. It's not a good book for getting into the nitty of, say, injection mold design, which is highly specialized.
I do believe Protolabs offers small batch injection molding for "reasonable" cost, probably as reasonable as you'll get for small batch. From my memory they also have a design guide PDF that you can download or they send when you register. That's probably a good place to start. Also try searching reddit r/mechanicalengineering for "injection mold" and similar queries, I do remember a few people asking for resources and getting good replies.
For metals alone you have several "chapters": milling (in several axes) Sheet metal (cutting,bending) Welding (in so many ways) Forging Casting (different processes) Brazing Sintering (for special cases) Etc..
My prototypes are usually made by using off-the-shelf brackets, profiles, fasteners etc where the most complex tools you would need are just for cutting, drilling, and tightening bolts. You may find that you can't get around needing a weld sometimes... Usually you can find local workshops that can weld simple Al or steel profiles together according to your drawing. Note: their feedback and experience is usually worth a lot (and given to you essentially for free when you order work).
Best of luck.
posting really to highlight this recommendation of trying to get involved with a local small-volume fabrication shop. you should be prepared for a certain amount of rejection (you're unlikely to represent a good return on time for these people), but if you can establish a good realtionship they know _alot_. not only will you learn an immense amount about processes and materials and costs, you'll learn about how to deal with that whole world.
I think it would be unreasonable to expect much more than an intuition from an intro course. But you make a good point. :)
Your wording here is a bit odd. Injection moulding is mostly a question of scale. Do you need to mass-produce your parts or are you just looking for mechanical properties that a standard 3D printer can't provide?
If it's mechanical properties, there may be other options like resin printing, casting or machining parts.
> How can I move to this "next level" of prototyping and small scale manufacture? Is this something I can achieve myself with (limited) investment in specific machinery (budget ~15k USD)?
You can get a (very) low end injection moulding machine for a bit over $2000 [0] and you can get a small desktop CNC milling machine for just under $3000 [1]. I would think about going for something more like a Tormach or SYIL but those are more like $10000.
You might also find Physics Anonymous' videos interesting. They bought a small injection moulding machine for a small run [2].
But there's going to be a huge learning curve here. Moulds are much more complicated mechanisms than static welded parts.
Before you get too invested in injection moulding, I'd really spend some time to see if you can manufacture the part some other way. Maybe talk to a job shop and ask them if they think they can fabricate it.
[0]: https://www.techkits.com/products/model-150a/
[1]: https://shop.carbide3d.com/products/nomad-3/nomad-3?variant=...
[2]: https://youtu.be/n7JWPxk92fY
To paraphrase: How/where do I start, as software engineer, to learn hardware, but not necessarily "computer" hardware?
*Not only limited to woodworking, they also build contraptions of some sort.
As an example, Adam Savage's "One Day Build" videos on the Tested YouTube channel are a good place to pick up idea for various techniques using a wide range of materials. You're probably not going to go out and replicate any of the specific builds, but it's a good way to build a mental library of ways to accomplish stuff.
That is just one example out of literally hundreds of good options. Along those same lines, channels like Simone Giertz, Laura Kampf, Evan & Katelyn, etc, etc (this list really could go on forever).
Are there specific projects you have in mind? Really the best way to learn is to not be afraid to try. Accept that you're probably not going to nail it the first time, and will screw stuff up along the way, but that's how you learn.
To give analogy in software development, I don't want to know how to build an app, I want to know what are the tools to build the app and why.
E.g. use IntelliJ for text editor because it's an IDE (Why IDE is important? Why not Notepad?), use Ngrok for tunnel (why?), use Charles for proxy (why?), use PostgreSQL for DB storing relational data (why? what's relational?), use Redis for caching (why?), etc.. you get the idea.
In my experience, what you're asking about is such a broad space there isn't one "thing" or even category of "things" that apply universally at a fundamental level. Getting good at making stuff is all about building up a broad catalog of options for tackling problems and building up the experience to be able to pick the right technique (or know when the
As an example, I was doing some DIY plumbing over the weekend. We were replacing the flooring in a bathroom in our house and when we removed the toilet we found that not only was the flange that mounts it to the floor totally rusted away, but the plywood on top of the subfloor was in pretty rough shape for a few inches around in every direction. I've never done anything like that before, but by leaning on various techniques I've watched people use in various YouTube videos over the years, I was able to effectively repair it (after calling a friend of mine who does have experience as a plumber to make sure my idea was reasonable).
Probably the most useful technique I used in that project was some approaches to pattern making (since I had to make an oddly shaped "ring" or plywood to fit around the drain) I learned about while watching a YouTube channel about rebuilding a wooden sailboat (https://www.youtube.com/c/SampsonBoatCo). That had nothing to do with plumbing when I watched it, but it was a useful approach that I was able to call upon for a more generalized problem. I think that's what the vast majority of "making stuff" is.
If there are more specific things you have in mind, then there may indeed be specific resources about how to make those things, but it sounded like you were asking a much more general question about making stuff in general.
> I want to know what are the tools to build the app and why 2. Are you interested in the fabrication and assembly of something (someone gives you blueprints and you gather and assemble the widget) or are you interested in going from I have an idea to I have a finished product?
3. Do you actually want to build something or just have the knowledge?
Injection molding machines get big and expensive quickly. But there are some hobby / education molding machines that are relatively inexpensive. They'll be limited in the part size, of course, but it will be very educational. You can find used industrial machines, but ones in a just-right size are harder to find.
You can make molds using high-temperature epoxy (hundreds of shots), high-temp SLA resin (presumably at least tens to hundreds), aluminum (thousands), or steel (often refurbished for very long lives). Having a CNC mill will be very helpful--something like a Tormach 440 is $7K or so new, and is useful for all kinds of things besides mold making. Depending on the complexity of the part and the finish you need, this is probably intermediate machining skill.
Machines are often rated in clamping force (e.g, "15-ton"), but shot size/volume (usually expressed as the weight per shot in polystyrene) and injection pressure are also important. Horizontal machines can take up a lot of space, but can use gravity to clear the part after it's made.
For smaller parts, Morgan makes some nice benchtop machines, but they're pricey. If I was going to buy a new machine, I might look at this cute little horizontal: www.robotdigg.com/product/657/ It's about $9K I think.
For me, it made all the sense in the world to buy an old import vertical 15-ton machine ($2,800 on eBay) and design and make my own aluminum molds for a product I sell. I learned a lot, and now can make other parts. I spent less than the cost of having a mold company make me a single mold (I think the quotes I had were $3,500 or so for my relatively simple, small part). But I have access and experience on a CNC mill, lathe, etc. If you don't have that, or don't live near a makerspace, then you'd need to factor in the machining equipment and tools.
I currently produce an ABS case for my product, actually resembles a DB-25 shell. About 2.5 x 1.5 x .8". I did use Fusion 360 CAD and CAM, and a Tormach CNC mill. Used aluminum for the two mold halves and spacers, actual ejector pins (they're inexpensive) for the ejectors. About a 40-second cycle time. It took quite a while to get everything put together (the manual is in Chinese, and actually is for a similar but not identical machine), and I'll probably add on some microprocessor control soon to make it a bit easier to run. It is extremely pleasing to be able to sit down and fill up a box with custom plastic parts. Need to add a logo or product name to the part? Throw it on the CNC mill and you're set.
How much would I pay to take a course to learn how to create molds and set up and run an injection molding machine? Right now I've spent less than I would having an outside company make just the molds. Your outlook may be different, but learning and creating actual products (subject to some size limitations) is very possible. It all depends on what value you place on learning new skills, versus the raw economics of it.
The booklet from Morgan called "Cutting costs in short-run plastics injection molding" covers simple mold making, and the case for using high-temperature epoxy for short-run molds.
The NYC CNC folks machined their own mold from a pre-built mold blank on their CNC machine, then had a company do the injection molding.
(I'm omitting the weeks I spent stripping and rebuilding a small pneumatic machine--it was just too small for my part. Another learning.)
By the way, I had a toy injection molding machine as a kid. Small but completely functional--came with a mold for a toy soldier, I think. I'd cut up sprues from plastic models. Probably burned my fingers more than once, but an excellent experience for a kid. Wish that was more common.
If you want to learn more about manufacturing techniques , this is the book I used in college which had a great breakdown IMO https://www.amazon.com/Fundamentals-Modern-Manufacturing-Mat...
Has to be a really good balance when it comes to machine quality and capabilities.