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by gh02t 3064 days ago
Yeah but I think there is a fundamental difference here. A 3D printer enables you to do things you can't do otherwise (fabricate custom mechanical parts). A pick-and-place enables you to do stuff you can already do with tweezers except in the most extreme cases. And likely do it faster than with a pick-and-place, because they require quite a lot of work to configure.

Edit: a good analogy is a homebrewer putting caps on beer bottles. You can do it by hand with a simple tool pretty easily - even capping 100 bottles at once is no sweat, really. It just doesn't make sense to have an automated bottle capping machine even if it was cheap, because it takes up space and ends up taking more effort to set up for a small run than it saves you. Pardon the pun, but the bottleneck lies elsewhere.

3 comments

As far as bottle capping machines you end up having to make custom handling parts and those are not cheap. (The chucks alone run several hundred dollars each.) Then the parts to guide the bottles through the machine have to be made specific to the bottle diameter and height. this costs several grand. There is still a lot of adjustment even after this. And if you want to change bottles or caps then outlay a ton more cash.

Capping them by hand despite the time and effort makes sense until you can afford a significant outlay in cost.

(I work for a machine shop that makes handling parts and retrofits capping/filler machines for the bottling industry. I don't fully know our prices but most of them would be far outside the range of any hobbyist starting out.)

Well, you can actually do stuff a 3d printer does by other means. It just typically requires more skills, and often more equipment.

I think your analogy falls down because an automatic bottlecapper does the same thing as you'd normally do by hand.

The difference for me is that a pick-and-place machine is an enabler. It would enable hobbyists to take on large-scale, distributed electronics projects - for which, right now, assembly time is normally the bottleneck.

If all hobbyists were solely interested in producing consumer-style devices, like bad versions of phones, or home-automation systems, then a pick-and-place machine wouldn't be a good idea for anyone. But there are actually lots of hobbyists that do stuff like data logging, where assembly time is a major problem.

There are hobbyists who might want to, I don't dispute that, but what I'm saying is there aren't enough. You need a pretty big critical mass before the economics start to make sense and something like what happened with 3D printers becomes possible. Projects at the scale you're talking about take a massive investment of time and skill independent of how long it takes to assemble boards, putting them out of reach of the vast majority of people simply because they don't have the time. Not to mention the cost of such a project; if you can afford to invest a thousand or more dollars in a hobby project then you can probably afford the tools you need to do it, too. Maybe I'm underestimating and there are tens of thousands of people out there wanting to build complex data logging networks with hundreds of nodes just for fun or some other equally ambitious project, but I doubt it.

> I think your analogy falls down because an automatic bottlecapper does the same thing as you'd normally do by hand.

That was my point. A pick and place does the same thing you'd normally do by hand with a pair of tweezers in about 10 minutes for a board of moderate complexity. Doing surface mount work by hand with tweezers is pretty easy. The only thing a pick and place enables is for you to do things at a large scale, because they have a substantial overhead to use that you only start to recoup around 50-100 units or more. Now, if we had some revolutionary device that you could set up in 10 minutes to feed dozens of parts and cost $500 then hell yes, I'd want one too. But I don't think that's possible at present no matter any economies of scale or design optimization, because a pick and place is actually quite a complex machine by simple necessity.

Not to mention that placing parts is only part of it - you still have to fabricate and drill the boards, load the machine, clean up any mis-places, reflow them in an oven, manually place any through hole or awkwardly shaped components and solder them, cut the boards, test them, program them, mount them, etc. A pick and place would definitely save you some time if you really want to do such a large project, but by itself I don't think it's gonna be enough to really make it accessible to an individual in their free time. I'm not disputing that they would be beneficial, just that they make sense for an individual working in their free time. Especially when you consider that contract manufacturing isn't that expensive, though it does come with its own set of hassles.

I don't think you're wrong.

I do think that a pick-and-place machine is probably more compatible with the hobbyist world than home CNC - given that CNC inherrently requires robust construction, and robust, accurate components are inherrently expensive. I mean - this machine looks more or less like a 3d printer with some reels, and a scanner. Once 3D printing becomes a cheap technology, things that require accurate repetitive movement become cheaper too.

I wouldn't be entirely surprised if stuff like small robotic arms become available to the hobbyist in the next 50 years or so, simply because being able to do arbitrary tasks with a high degree of accuracy is incredibly useful.

At the point where CNC, not as in cutting, but as in general computer-controlled movement, is an ordinary part of the workshop, I wouldn't be surprised if things like this ended up in hobbbyist spaces.

You can already get 'em and the price isn't completely out of reach for a hobbyist:

https://www.sparkfun.com/products/14342

I had actually just discovered those recently and with 0.2mm repeatability my first thought was a pick and place. But the complexity ends up being with the part feed and with configuration. It's really hard to build a machine that can reliably feed arbitrary parts automatically, and then programming it for each job is a pain so you'd also have to revolutionize the tooling so that a person could program one in a few minutes (and don't forget loading it ugh). The kinematics do share a lot with 3D printers, but it's the open-endedness in the feed system that makes them difficult. It's probably not impossible, just really hard, so there needs to be a considerable market to recoup the cost of designing such a machine that is accessible to a hobbyist.

I mostly agree with CNC, though it depends on how ambitious you are. I have a very cheap generic CNC engraver ($100 + shipping) that I use to engrave PCBs and it actually works quite well for that as well as it can do wood and soft materials remarkably nicely. Ditto for nicer machines like the Sienci, especially if you're doing woodworking. But a 5 axis machine capable of milling metal for <$500? It's not gonna happen. And even if it did, would you really want one? Milling metal is always gonna be complex and full of hassles.

I feel the same way about laser cutters. They're actually affordable now and I definitely want one, but I don't wanna deal with the considerable inherent hassle. Fires, toxic fumes, permanent blindness, focusing etc, just not worth it to me even for free.

Also this has been an interesting discussion, thanks.

Wow - that is beautiful.

You're almost certainly right about good metal-milling CNC machines never being cheap. I think the only possibility to make such a thing economical would be by re-purposing car parts (I think if you could work out a way to use common car parts and clever software, you could step around the fact that things manufactured to high tolerances out of steel are expensive - since car parts are both cheap, and well-made).

That said, the thing that really excites me about CNC is just how much it opens up a whole load of projects that I haven't had the tooling or the mechanical skill to take on. I'm a bad carpenter, so when I make things out of wood, I tend to have to allow massive tolerances in everything I do. Even a CNC that could only cut softwood would be really useful for me.

I've actually been ummming and ahhing about buying one of ali-express - where did you get your engraver from?

> And likely do it faster than with a pick-and-place, because they require quite a lot of work to configure.

So lets figure out ways to bring down the amount of work required to configure it! ;)

A "reel" library (tape library) is going to be very expensive.