Tuesday, November 12, 2013

Industry on mars

CJ made such a great comment that it deserves a detailed reply...

I agree that building tractor from parts is easy (And with or without 3d printing, they'll have to be able to do that). But, shipping all those parts from Earth would be a lot of upmass. For the first few, not a problem, but I don't think that's viable long term. So, they'd need to go ISRU for parts (for both new tractors and repair parts on older ones.)

My scenario is a dozen colonists on the first mission and 26 months later three dozen more. Mission planners need to understand that a viable colony needs lots of skilled people. A single person might have all the skills four dozen have, but they don't have the production capability of four dozen lesser skilled people. I propose just one lander with parts for two tractors to support the first dozen colonists. After that, yes, it's all ISRU although the earth may be more generous than I am. I think those first dozen are capable of taking it from there, but absolutely they should be (if we send people with the correct skills) after the second mission which I will explain more in the following replies...

But... you mention skilled machinists making parts in seconds. Sorry, but I think you're way off on the timescale. Okay, try this (It caused me a rude awakening once); go to a machinist and ask if he can make you a new cylinder head, or for a Mars tractor, I'm thinking the electric motors, suspension, steering, etc Sure, he can make leaf springs for the suspension, but he can't make the shock absorbers. So, do without those, but what about the motors? 

I've worked with machinists and it is amazing watching them do their thing. When I said seconds, I meant seconds. But that does not include the time to get to that point. I gave the example of washers which is a very simple part that makes up about 30% of the bill of materials for making the example tractor which would have to be adapted to a martian design but makes a good reference. They might start by pouring some iron into a dirt mold to make a rod. They would turn that rod to make a cylinder. Then they would slice that cylinder into shorter rods they could drill (not a hand drill but in a pinch they could use that.) Then they slice that short drilled rod into washers. That's the part that takes seconds. That's for a very simple part, so yes I was a bit misleading, but more complicated parts are done the same way... a series of simpler steps (not perhaps the ones I would come up with, machinists are smarter than me in this area) except more of them of course.

There's always setup and preparation, but once that's done (and perhaps takes a bit longer if they lack coffee) they can crank out a lot of identical parts in a day. (Clarification: a single part often requires several steps all of which require setup before production.) As a matter of fact, those jobs (prep and cranking out parts) are usually assigned to different machinists because they are two different personalities but they could be done by the same person. Sure, if you ask a machinist to do just one complicated part they will take time (and more coffee) but it will get done. I had friends with a company in a very small town (by small I mean a few thousand people hundreds of miles from anyplace bigger) that made electric motors and it is simply amazing watching them work. But ultimately you are right, making parts takes time. Almost anything can be made in a day or two however (in most cases you're talking about hundreds if not thousands of identical parts in a single day.) Keep in mind the parts you referenced are themselves actually made from multiple parts. So let's say on average it takes a day per part (and from seeing it being done I know that's generous.) In that case it would take them 1000 days to make the parts for a single tractor which is not bad since 8 hrs later it's assembled and added to the colonies assets (which is to say one colonist ordered and payed for it from those that had the skills to make it.) But they wouldn't do that.

They would never spend that time to only make parts for one tractor. Making multiple parts takes less time per part than making single parts. So in that thirty-four months they would make parts for perhaps a dozen tractors instead. Partly by having that one prep machinist work with a number of line machinists. More hands make lighter work. That electric motor company I mentioned only had about five employees and cranked out several motors of different models per day. Only the owner was the really skilled person and spent some of his time on administrative duties. However, they didn't make their own castings, rotors, coated wires and magnets. That would come from a different group but they also could work faster than you might imagine. Making wire is a simple extrusion process, dipped in a liquid insulator before being wound on a spool all in a continuous process. That process itself requires setup but production is much faster. As a matter of fact, setup may be all that requires a skilled person since production could be highly automated with a non machinist doing loading and unloading. That setup would be something repetitive itself, not requiring as much skill as coming up with the process in the first place. Everything complicated is made up of simple steps.

Designing the tractor to be easy to build would obviate most of the issues, but far from all. Forging isn't easy (ever watched it being done?) and even making steel requires a smelter and factory (plus a lot of O2). Also, ask a machinist if he can make a plain old nut and bolt that's interchangeable with others; yes, he can, if he has the right equipment, but it's going to take a huge amount of time and work, every time, and the machinery to do it en mass would fill several landers. 

Industrial forging I haven't personally seen (other than those TV channels that will occasionally touch upon it) but I have done it myself in shop class as a kid almost four decades ago. The martians will build their capabilities over time and will specialize like any industrial society. They certainly will not start at a high level at first and none of the machinery will come from earth. Keep in mind a single blacksmith is a forger. From there you scale up. You are absolutely right about the importance of design and that will be the thing martians will be skilled at because of necessity. They will also be supported by millions of designers on earth that will do it for free (including transmission of their designs to the martians) just to be a part of such an adventure.

Bolts you might just stamp with some post production. Nuts, you would probably stamp and then tap (many at a time with a rig set up to do that.) BTW, coming up with the machines and rigs to make parts is a major part of what a top machinist does.

For another example, try asking a machinist to make a car transmission. He won't be able to. Same with a new engine, or even a master brake cylinder (as many a classic car buss has learned to their dismay). You can do a lot in a machine shop, but that's cutting, not casting, and some shapes just can't be made via cutting alone. 

A machine shop is not just cutting. It's slicing, pounding, bending, turning, milling, grinding, pouring, compressing (which includes stamping and other variations) etc. I agree that casting often precedes machining if required at all after casting.

No a machinist does not make a transmission, but he will be able to make all the parts which a skilled transmission mechanic will then assemble (other than parts that don't require his/her skills such as casting.) (S)He doesn't even have to know what the parts being made are for. Again, this is where design becomes important. That tractor doesn't have a typical transmission, it's completely hydraulic. Yes, they can make all the hydraulic parts (the fittings anyway, hoses are made by somebody else.)

For small, simple parts like nuts, bolts, joints, sockets, etc, 3d printing would IMHO be far easier. (for washers, stamping is easier, but only if you need a lot) 

3D printing has the advantage of flexibility but almost always loses the time of production race compared to other industrial processes some of which go back to the stone age.

Or what about small plastic parts, such as the cooling fan (just the blades) for a computer, or a space suit? Think about the infrastructure needed to make a new one; it's a lot. Or, you have to take along huge parts inventories. Far easier to print what you need.

You could but actually, I think that's where 3D printing really finds it's niche. Not in making the parts themselves but making the molds for an injection molding process which makes the parts magnitudes faster than 3D printing. 3D printing is more likely to be used when you just need that one missing part rather than a production line of them. As an example I read about a lady using 3D printing to make cookie cutters of her own design. She was a small operation but still needed five printers to keep up with orders. If her company gets any bigger, I guarantee she would have been smarter to buy just one printer and do production with injection molding. That's where she'll end up in any case (actually, probably using another injection molding company to provide fulfillment services.)

I don't see 3d printing as a show stopper (You can do it without it) but I think viable 3d printing could make the bootstrapping process far, far easier, as well as being far easier on the upmass side. 

Agreed.

There are other showstoppers for Mars colonization, but even I don't think lack of 3d is one of them. I just think it would make it a lot easier, especially in a colony's early days, and especially if its on a tight upmass budget. 

Absolutely right.

Now, what very well be a true showstopper regarding Mars colonization is an issue I've yet to see addressed; proper food preparation. Specifically, how do you design a smoking grill for Mars? You need hardwood or mesquite wood for it, and growing it would take years, and there's the smoke to consider, etc. After all, without real BBq ribs, human life cannot exist. :-)

Ya got me there. But even that will be accomplished in a shorter space of time than most imagine. Same goes for livestock.

Secondly, coffee; good coffee hasn't been successfully grown in greenhouses here on earth, so have we even researched how this can be done on Mars? This should be a primary research goal, placed well ahead of other, less critical colony necessities such as air and water. 
:-)

I see your point. You've been absolutely great CJ. Thank you and keep it up please.

Finally I should say, very early they would not dedicate themselves to making parts for one product. They would simply make parts in volume related to orders not even knowing what those parts are going to be used for. You don't need a central plan.

Also, it's not just metal or plastic parts. I worked for a company that worked with beryllium oxide ceramics. Part of their manufacturing was hydraulically stamped from powder and those parts (thousands of them) took less than a second per part (granted martians would have a less capable press to start, but there's nothing preventing them from scaling up if they have the need.)

When I say "none of the machinery will come from earth" I do not mean it as an absolute statement. Where it makes sense they will import things from earth but even then probably only as part of the new incoming colonists mass allowment. Material for all the massive things they need are already on mars. They would not import those things. Yes, earth could make fancier things than they could make for themselves until they develop more. They will never need those things until they are capable of making those themselves. About the only thing I can think of is advanced microprocessors. Most other electronics will be completely within their own capabilities to produce. They will not even have to go through the brick cell phone stage. The entire core cell phone electronics are a single chip or two they can import. A single satellite sent from earth will take care of all their phone and internet needs for quite some time (allowing them to roam half the planet.) I can see all colonists having something like an Ubuntu phone which only requires a keyboard and monitor to be a desktop computer. The monitors would be an import but the keyboards they could certainly make themselves. Yes, I know the Ubuntu Edge Kickstarter project failed, but I'm talking capabilities here.

5 comments:

Anonymous said...

Wow, thanks for the post.

I don't think we fundamentally disagree. My main concerns come down to man hours and upmass, and how to best utilize both.

A big part of the reason custom-made things with fine tolerances (we see this with spacecraft)is the sheer number of man hours required to build something complex by hand.

The colonists will have a finite supply of man-hours, with many different things requiring their attention. *if* 3d can minimize some of that, I think it's worth utilizing (or as you said, adding it to the toolbox).

I think 3d could be the best choice for some things, such as some complex plastic parts. As for metal... *if* it progresses to a point where it's viable, great, it might be good for some things (faster and easier than other methods).

You listed some good examples of what 3d would not be good for, such as wire. I agree, and upon thinking about it, printing a chassis as I suggested would be impractical at best.

Okay, for an example, let's use the first thing the colonists will use, and will have to either produce themselves or import from earth: Espresso makers.

Some parts are simple metal castings, such as the boiler (assuming they go that route... some use thermoblocks instead). There's some metal piping, which would be best made by simply extruding a tube and bending it. There are plastic parts of complex and varying shapes, such as the milk frother head, the case, the water reservoir, etc, that might be best made by 3d printing until true mass production is feasible (and it won't be until the colony grows large enough to warrant mass production)You'll still need glass for the little pot, heating elements, and pumps (again depending on which type, pump or boiler, you're making) and those might be too specialized and demanding to make in Mars in the early days, so those could be imported from Earth (better and easier than having to dedicate multiple landers to delivering entire espresso machines to Mars). #d would play a role, but only where it was the best option from a manpower and upmass POV.

I worded my nuts and bolts claim regarding 3d very poorly. you're right, for making more than a few, 3d wouldn't be good (and the tech to do this easily with metal isn't quite there yet). But if you suddenly need a spare part, it might be the best option, especially in the very early days.

I'm going to cut this in half here, because I'm getting a message saying my HTML cannot be accepted, and must be at most 4096 characters. (I'm using no HTML tags)

Anonymous said...

Part 2



3d for making molds... I think that's ideal, and already being done.

I absolutely agree that they don't need to have a central plan. In fact, I think they need to not have one, because having one increases the chance of failure.

They will need to have priorities though, such as (in order of importance) coffee, water (required for coffee), air, food, and livable (as opposed to tuna can tiny) shelter. But, those kind of priorities don't require a plan, because aside from air, they've been true of colonists and pioneers for centuries, and they didn't have central planning.

Oh, wait... I can think of one exception, the Plymouth colony. They had central planning and mandatory communal sharing (essentially communism). And many of them died of starvation because of it, until they got rid of it.

And as an aside, I think a Mars colony might be economically viable in a way I've yet to see mentioned; we'll learn a great deal (including useful new discoveries, such as in chemical synthesis)and that sort of new knowledge could make for a very valuable Martian export. Going further, once there's return traffic from Mars, I can see Martian gemstones being a very hot commodity, especially if Mars' geochemistry has created types that don't exist on earth (quite possible given the vast variety on Earth, some of which are limited to single sources). Transporting items from Mars to Earth would be very low cost if we're talking cargo vehicles that would otherwise be returning empty.

But I think knowledge will be the most valuable "export", including monetarily. We won't ever know what we can learn, unless we try.

Arizona CJ

ken_anthony said...

I think 3d could be the best choice for some things

Absolutely right. We agree.

Import/Export

This is where an Aldrin cycler may make a great deal of sense perhaps. It may allow your gems to travel at a marginal cost. Otherwise you have the problem Elon described in that crack cocaine would not be a profitable import from LEO.

I like your comments so much... how would you like me to make you a guest editor? I have no readership but so what? That way you will not have to mess with this comment section if you don't want.

Anonymous said...

"Absolutely right, we agree."

But... this is the internet, where I don't think that's allowed?

Great point on the cost per pound issue Elon brought up; yep, whatever is shipped needs to be either using otherwise-wasted capacity or be massively valuable per ounce. That'd be the beauty of "exporting" patentable new discoveries; information has zero mass.

I like your comments so much... how would you like me to make you a guest editor? I have no readership but so what? That way you will not have to mess with this comment section if you don't want.

Ken, I would be deeply honored, as well as delighted. However, please bear in mind that I have no clue how to use blogger in that way. Also, if at any time you decide I'm not suitable, feel free to give me the boot with no hard feelings; this is your blog, your rules.

I'm trying to figure out how to get my e-mail addy to you without posting it.

Arizona CJ

ken_anthony said...

Just email me...

kenneth_john@yahoo.com