<kristianpaul> wpwrak: nice caps!
<kristianpaul> you mean  extrusion  in software?
<kristianpaul> thats interesting, or you get a personal 3d printer? :-)
<roh> wants to play around with injection molding. .. JUST need to get my hands onto hw (or build own!)
<roh> _after_ completing the cases .. and the camp :=)
<wolfspraul> roh: how is the case work going? got the material back?
<roh> if it can be done in a vending machine, it can be done in a hackerspace :) http://www.replicationdevices.com/vintage.html
<roh> wolfspraul: yeah. fetched it today.. payed in cash *sigh*
<roh> used the day to sort and clean up parts
<kristianpaul> ha, now i cant complain openscad is slow in render after reading results for this cadmium..
<roh> looks good so far. will do fit-tests later
<kristianpaul> fit, *green*
<kristianpaul> or was grin :p
<roh> then i 'only' need to glue another 480 parts together to make up 240 buttons
<roh> and package the whole thing.. man .. thats a lot of acryllic
<wolfspraul> and the logo
<roh> didnt get so far yet
<wolfspraul> sure, the other stuff first. but it soudns good. congratulations you got it this far!
<wolfspraul> Adam is still in the critical testing phase, some things look suspicious but I have to be patient and wait another 2 days or so before we know more statistics :-)
<roh> thanks. how should i package it btw? as 'kits' or rather 'bulk' ?
<wolfspraul> bulk is probably easier for you
<wolfspraul> and to me there is no advantage of packaging it in kits
<roh> doesnt really matter.. need to do qc and counting etc anyhow
<wolfspraul> up to you, pick the easier one
<roh> ok. we'll see whats easier to package
<wolfspraul> but since I hope we do logos, do bulk packing then that's just one pack to go through to add the logo
<roh> true
<wolfspraul> roh: have you seen an injection moulding process/machine? if you want to go in that direction, I suggest to visit an existing shop first.
<wolfspraul> I did one or two visits, and I wouldn't know right away how to break this down for a smaller shop, it looks like a process that does need a rather high minimum capital investment, and minimum monthly production quota to make sense
<roh> wolfspraul: havent seen one in person yet. but simply the point that somebody successfully operated vending machines in the us means it can't be too dangerous ;)
<wolfspraul> the problem is the size of the machines and complexity of the overall process
<roh> true. but it seems to fit in a machine big as a vending machine, so i can put it in a hackerspace
<wolfspraul> steel tool design, steel tool making, steel tool storage, plastics storage, injection moulding machines
<roh> i dont expect perfect results. and i got a mill to make my own molds. so the most expensive parts i can make myself
<wolfspraul> ok I went to a big factory, but like I said I have a hard time imagining how to scale it down
<wolfspraul> the machines are big, really big, and they need a lot of pressure
<wolfspraul> well, you can try. I don't want to stop you :-)
<roh> it will get much more complicated for bigger parts for sure. i was thinking about starting with something about the size of a box of cigarettes similar to that of the vending thing
<wolfspraul> in order to make plastic pieces for a few cents, you need a lot of capital invested, and you better have customers ordering millions of plastic pieces from you each month
<wolfspraul> I think if you scale down, each piece will get more and more expensive
<wolfspraul> to the point that lasered acrylic doesn't look that expensive anymore
<wolfspraul> how about milling or lasering aluminum?
<roh> the thing is: even former 'complex' or expensive stuff got really cheap for some weird product in the last 20 years. lots of machines built 30 years and more ago couldnt use the cool manufacturing processes we have now. i can go over the street and do custom lasercutting in a company for an investment of < 100E
<wolfspraul> yes but that process is very well suited for customization
<wolfspraul> so there are shops that support themselves with a large number of small orders
<roh> milling aluminium i can do. maximum piece our mill can do is ~24x12x20cm (xyz)
<wolfspraul> the injection moulding process I have seen is not well suited for customization
<wolfspraul> it's all fine, but you need to make 50k or 100k pieces, and the factory you will make them at will be _big_, even physically.
<roh> injection moulding is only 'cheap' if you do lots of unchanged parts. sure. the 'setup' (milling the molds) is expensive. but atleast the 'using' the mold is much cheaper than what milling or cutting can do
<roh> my goal is to make something which can be built for <1000E investment and do parts with better resolution/quality of that a makerbot printer can do
<kristianpaul> i hope <500E ;-)
<roh> kristianpaul: well.. you will need a mill to make the molds, thats not included
<kristianpaul> of course
<kristianpaul> wich material had you tought to inject in the mold?
<wolfspraul> I think you will be in a long learning process there.
<wolfspraul> I have only seen a little, but my understanding is the process needs huge pressure. You cannot make good parts with aluminum moulds at all. You need steel moulds, and even then you need to harden the most exposed parts of the surface.
<wolfspraul> I suggest to go to an existing maker and have them show you the process and some pieces that were made in different ways, including aluminum moulds
<wolfspraul> btw, I think you can use silicone moulds as well, with a different plastics material. you just let the liquid run into the silicone mould, something like that.
<kristianpaul> hum, aluminum moulds indeed sounds challenging..
<wolfspraul> it's only good for 10-20 pieces though, maybe a bit cheaper than cnc if you need 20
<kristianpaul> i liked werner Counterweight mold process.. and wast so long.. but still limited for some kind of shapes and resolution.. and material
<roh> kristianpaul: not sure what polymers are useful. will need to research that.
<roh> hm. need to build another rig to glue the button caps. but i have an idea already
<roh> and i think its easier for you if i do kits. else you need to pair the buttons to the right panels yourself
<kristianpaul> may be do mold in wood, and inject PLA using a gun or something..
<kristianpaul> damn i dont have CNC machine at home.. and not that i will soon..
<roh> start a hackerspace and find other people who want similar toys to share
<roh> or find a hackerspace
<kristianpaul> we have a hacker*lab
<kristianpaul> but not spave
<kristianpaul> not needed
<wolfspraul> roh: pair buttons to right panels?
<wolfspraul> aren't they all the same?
<roh> well... tolerances for acryllic are this:
<roh> Toleranz = ± (0,4 + 0,1 x Dicke) mm.
<roh> means with 3mm it can be 2.3 to 3.7mm thick
<roh> i already what one can do to compensate, but some of that means pairing fitting parts
<roh> the material i got this time was inbetween 2.7 and 3.6mm
<wolfspraul> ok but anybody can do the matching
<roh> i measured every sheet on every corner, and noted the min and max on the sheets and sorted them, the thinner ones became sidepanels, the thicker ones top/bottom
<roh> if you have somebody to do that puzzling afterwards i can also put them all into one big bag
<wolfspraul> hmm
<wolfspraul> your sorting system may be lost in translation anyway
<wolfspraul> just 'may'
<wolfspraul> btw, if it makes you feel better, matching/pairing of mechanical parts is regularly done at any factory I've seen
<wolfspraul> everything has tolerances, even part produced by the most fearful 3m high injection moulding monster with hardened steel moulds
<wolfspraul> so since the injection moulding is normally done in a separate company/shop, matching/pairing is done as part of the iqc (incoming quality control) of the smt/assembly shop
<wolfspraul> which is probably the place in the process that makes the most sense, because those girls can have piles of parts, and quickly find matching ones. they also decide which ones to return to the plastics shop, which can be as high as 10% regularly.
<wolfspraul> because it's too hard to find a match/pair
<wolfspraul> so you are right, if you want to do this matching, it's probably best to ship in kits
<wolfspraul> then adam doesn't have to figure the whole tolerances thing out
<roh> i can add a A4 paper sheet ontop of each box 'danger! tolerances inside'
<kristianpaul> :-)
<roh> btw.. how big is your army to assemble that pile?
<wolfspraul> 1 man
<roh> uh.kay...
<wolfspraul> he's doing SMT reworks, testing, assembly, packaging, shipping
<wolfspraul> nice, eh? :-)
<roh> yep.
<kristianpaul> on the go? or the idea is to have all the packages ready at once?
<roh> .oO(this product may contain leftover crazyness of all involved parties)
<kristianpaul> haha
<roh> i have some pictures of the process.. will need to collect them all (different cameras) some time afterwards
<wolfspraul> kristianpaul: it's overlapped, I think we do quite well so far. Adam is doing testing right now for example.
<kristianpaul> (overlapped) true, i forgot that
<wolfspraul> there were some nasty discoveries testing the first few boards, let's see how that develops. But whatever we find, we can only move forward.
<kristianpaul> yeah, i read backlock. hope that can be fixed..
<wolfspraul> the 'normal' OEM would throw a lot more people at this process, say 50, with suppliers even more, hundreds
<roh> but its good we moved. i wouldnt have been possible to do so much kits in one batch in the old location. not enough free spare tables one can occupy for days
<roh> now i can use the '/tmp/swap' labeld cabin with a big 'danger chemicals' on the door
<kristianpaul> in rc2 adam was in the SMT personally, this time not needed? or my first asumption is not true?
<kristianpaul> well you, and adam i remenber..
<wolfspraul> I would know how to manage this, I think :-) but I don't have the capital to attack the problem like this. And also we would then be under huge pressure to produce a lot, start the next version right away, and so on. Because all these people need to do something.
<wolfspraul> we don't want that either, it would be overwhelming and we would just produced bad quality products
<wolfspraul> so we find a middle way through this
<wolfspraul> if we can manage to build traction with users (=sales), we will ramp up the whole thing
<wolfspraul> if not, at least we are not under a mountain of debt that forces us to do stupid things
<roh> i am sure we will even find interresting results on the way doing stuff on a much tigher budget compensating in time and reproduceability
<roh> for me atleast thats a very important goal when searching for a solution how to do stuff... not 'how do i get it done now' but 'how can i make that possible 10000times the same way.
<wpwrak> wolfspraul: (1 man factory) ACME = Adam Can Make Everything ;-)
<wpwrak> (injection molding) from what i hear, aluminium is used quite regularly for low volumes (100s). it probably has some other restrictions (geometry, types of plastics, etc.)
<wpwrak> the industrial process probably also aims to have a high open-loop yield, which wouldn't be a big issue for a DIY process
<wpwrak> also, the industrial process aims to be as fast as possible. again, DIY cares much less about this. this means that you can try completely different heating approaches. e.g., i would heat the mold and go easy on the pressure.
<wpwrak> then, high pressure is not so hard to produce. there are manual bench presses that give you quite a lot of pressure. the challenge is then to combine all this with heating, and make sure things don't slip and splatter hot plastic all around you
<wpwrak> (well, still better than molten lead. the gravity casting i used for the counterweight is pleasantly safe in that regard ;-)
<wpwrak> next, if you just want to test drive your mold, you could use a plastic with very friendly characteristics (e.g., a lot meltung point), such as a mix of polyethylene and wax
<wpwrak> btw, i don't know if one could also make molds of brass or bronze. according to some sources, these materials may be even easier to mill than aluminium. plus, they have a higher melting point, which means that you could probably heat them on a gas stove
<wpwrak> regarding molds, the industrial process may also show some co-evolution: since making a mold is expensive, you want to make the most of it, which justifies expensive machinery and complex processes. this in turn justifies expensive molds, and so on.
<wpwrak> nowadays, the machinery to make a low-performance mold can be had for a few kUSD. and maybe even 3D printing a mold would be possible now, which would need a larger initial investment but would simplify and accelerate the process even more.
<wpwrak> now, if the cost of a mold gets low, you can consider making a larger number of molds, instead of the one super-expensive one of selected exotic steels
<wpwrak> once you have this, you can lengthen your pipeline and relax the thermal profile
<roh> wpwrak: even if a mold is 'hundredts' of euros, its feasible if you want 3-4 digit parts
<roh> because its still loads cheaper than printing or milling
<roh> i was thinking of custom parts i couldnt yet find anywhere. like a diy case for handlebar mounting (for doing electronics and mount them to a bike)
<wolfspraul> wpwrak: yes, I think for the 'typical' process nowadays it's multiple factors that drive prices up. but the goal is to bring the per-unit price down, right? so the fact that it evolved towards 50k USD molds and giant injection machines means that that is where the sweet spot is, _IF_ you make hundreds of thousands of parts.
<wpwrak> yup. well, thanks to apple, there should now be "CNC farms" than do things like magnesium cases by the score in parallel :)
<wolfspraul> maybe you first define your economic end goals - how much do you want the case to cost?
<wolfspraul> that will narrow down the options a lot
<wolfspraul> and the path becomes more clear too then
<roh> true. i want machines where the sweetspot is low as 2-4 digits.
<wolfspraul> cases go from 50 cents to 2000 USD :-)
<wolfspraul> let's start somewhere. then you need to answer: where in that range do you want to be?
<wolfspraul> if it must be < 2 USD, there are only a few options/paths
<roh> 10-20E
<roh> of invest per product
<roh> eh sold product.
<wolfspraul> ok good. with that number in mind you can check which process works.
<wpwrak> wolfspraul: at a few runs of 100k+, the machine cost becomes largely irrelevant. we can't compete with this directly because we have no means to overcome this sort of barrier.
<wolfspraul> yes but we are discussing processes and materials
<wolfspraul> and I proposed to first define a goal of the per-unit costs
<wpwrak> we're also discussing rapid and low-cost prototyping :)
<roh> i dont fear some pressured air/valve/arduino foobar.
<wolfspraul> because that will exclude some processes and materials, and as we go and learn about the various processes, we can quickly eliminate some and continue exploring others
<wolfspraul> keep the end per-unit cost in mind
<wpwrak> if you take the DIY route, you need to improvise a low anyway. that's also an opportunity to swap parts of the process.
<roh> there is a full box of festo stuff around also. more difficult is the 'how to melt plastic safely' part i guess
<wolfspraul> because that's what all of these processes and materials were designed for (most of them anyway)
<wolfspraul> someone had a certain USD value he had to reach - then a particular process was created
<wpwrak> i wouldn't worry about the end unit cost for now. that's something you can only assess after optimization.
<wolfspraul> I suggest the thought path the other way round.
<roh> well.. time to find out where to get good diy compressors and stuff.
<wolfspraul> because we do not need to duplicate all industry.
<wolfspraul> so if we define a per-unit cost we want to achieve, we can go through the processes and machines that others have developed already and see which ones fit our needs
<wpwrak> roh: why not just use a manual press ?
<wolfspraul> if you start from scratch, I think it will be a long path and in the end you have something that is not economically feasible
<roh> wpwrak: i was thinking more of the one needed to move the liquid plastic than the one holding the form (that can be manual for now. or pneumatics)
<roh> i have a compressor downstairs with 80litre tank and up to 8 bar.
<wpwrak> wolfspraul: i see the current problem in the high up-front cost of injection molding. that's not only a problem for going to production (at which time, you'll already have to have acquired some financing), but it also affects the development
<roh> well.. first the acrylic madness
<wolfspraul> wpwrak: I agree. fully agree. I'm just saying let's define the targeted per-unit cost first, and keep that number in mind throughout our work. that's all.
<wpwrak> roh: (plastic) yes, there are some designs that have a heated cylinder with a plunger you push down
<wolfspraul> it will guide us, and help eliminate options
<wolfspraul> and roh did that, he said 10-20 EUR
<wolfspraul> so that's good
<roh> maybe even a step between casting and molding is useable. use some more plastic and mill it nice afterwards. _much_ less time than using 'full blocks of plastic/metal' and less wear -> cheaper
<wolfspraul> don't underestimate how much others have optimized already, the entire industry for decades. We cannot quickly come in with all our genius and find the one optimization that leads to a high-quality low-volume and still cheap case. no way :-)
<wpwrak> wolfspraul: (unit cost) assume an order size of ten. then we're talking :)
<wolfspraul> no fix the per-unit cash value first
<wolfspraul> then you may have certain MOQ, depending on process
<wolfspraul> but I propose to think in that order
<wolfspraul> not process first
<wolfspraul> but anyway, roh seems to be clear about that (10-20EUR), so that's good!
<wpwrak> you can reverse it - take your quantity, then look at what the industrial process costs. that gives you an upper bound.
<wpwrak> if you're cheaper, you win.
<wpwrak> if you can make more and are still cheaper, you win too.
<wolfspraul> work from per-unit cost backwards, my 2c
<roh> anyways.. its currently _not_ raining so i will use that opportunity to get home
<wpwrak> wolfspraul: i think we're approaching this from different ends. i want to extend the range of things we can cover during development. you want to optimize the mass production process.
<wpwrak> if the development process, it's a bonus if it can also cover part of the mass production domain. this is basically what you're doing with the acrylic cases now.
<wpwrak> although you're probably not very cost-effective. may have been cheaper to put roh on a plane to buga and let him visit that super-cheap laser cutting shop, and let them make the cases ;-)
<wolfspraul> I think a lot of the machines and processes you find today were created because someone targeted a lower per-unit cost for himself. (including whatever order quantity he had at the time)
<wolfspraul> ah no
<wolfspraul> I am very clear about material costs
<roh> on mechanics material isnt the expensive part. its machine cost and runtime (atleast in all my cases)
<wolfspraul> I work with roh because I also (try to) subsidize his design and openess work
<roh> the acryllic doesnt even cost half of what lasering it does
<wpwrak> (come in with our genius) it's not only that. it's also new tools. for example, low-cost CNC is something relatively new.
<roh> same goes for milling
<roh> even more dramatic when using wood (material worth cents)
<wpwrak> wolfspraul: (subsidize roh) that's good. but i wonder how much of this really stays in his pockets. seems that most of it goes to the laser shop now anyway
<wolfspraul> it goes to many places
<wolfspraul> his work is also very labor intensive
<wpwrak> wolfspraul: so perhaps it would have been easier to just take the work to buga and simply give roh some of savings as a token of gratitude :)
<wpwrak> s/some of/some of the/
<wolfspraul> maybe in the future we can do that yes, like a design royalty, and all manufacturing happening in China
<wolfspraul> we see
<wolfspraul> I like to work with raumfahrtagentur and roh :-) with all ups and downs :-)
<roh> yes.. we will hopefully figure something out ;)
<wolfspraul> good mechanical work is very important for me in the future, for copyleft hardware
<wolfspraul> wpwrak: not buga, China (sorry Buga :-))
<roh> whereever buga is?
<wolfspraul> it's a nice town in Colombia
<roh> heh.;)
<wolfspraul> and the laser shop was even in Bogota actually
<wolfspraul> anyway
<wolfspraul> nothing can beat China on any of those things, if you just want to do it there
<wolfspraul> many machines are coming from China now
<wolfspraul> electricity is dirt cheap
<wolfspraul> no environment standards whatsoever, dump anything you have in the toilet
<wolfspraul> no worker rights whatsoever
<wolfspraul> giant domestic market with nearly infinite amount of service providers and shops and companies
<wolfspraul> and so on
<roh> given the amount of tricky details i encounterd.. i can basically limit the reproduceablity of the product in quality be the grade of detail in the documentation
<wolfspraul> but I still need raumfahrtagentur :-)
<wpwrak> (bogota vs. buga) ah, make more sense. i was wondering how on earth kristianpaul could have such a shop basically right at his doorstep :)
<roh> well.. bbl. driving home now.
<wolfspraul> I work with raumfartagentur _because_ they are documenting well
<wolfspraul> if that goes away there is no difference to China :-)
<wpwrak> (china) yeah. depends on the cost of finding a place that'll do it vs. the savings compared to kristianpaul's lucky find
<wolfspraul> oh, no problem
<wolfspraul> come to Shanghai one day, or Shenzhen, or dozens of other multi-million people cities...
<wolfspraul> but my goals are different, I want deep documentation, and I want to work with places that can do innovative things, experiments
<wpwrak> sure. just seems to be a bit inefficient to tie up people like roh with chinese manfacturing
<wolfspraul> you mean the run of 80?
<wolfspraul> too much manual work for roh?
<wolfspraul> he needs to speak up himself, that's a problem of optimization that you can only optimize well if you have the problem right in front of you
<wpwrak> he seems to grumble a lot. but maybe that's just the noises he makes when he's happy :)
<larsc> i wouldn't count on that
<wolfspraul> it's also why I say we should not under-estimate the optimizations others have done already
<wolfspraul> let's get this run of 80 done now, then we try to sell them, then we think about the next steps
<wolfspraul> I am not particularly proud of a process that involves workers without rights either. But I need to be smart in which problem I attack in which order.
<wolfspraul> for example I could spend some money to get rid of that metal sheet
<wolfspraul> the metal sheet causes a lot of work
<wolfspraul> it's something we could get rid of if we would focus on it and spend some serious engineering time
<wolfspraul> too many problems all over...
<wolfspraul> also right now it seems the rc3 run will give us quite some headache on the electrical side, at least that's what I see in the early test results
<wolfspraul> bah
<wolfspraul> just when I thought the weekend starts! :-)
<wolfspraul> I don't want copyleft hardware to depend on a process that ruins the environment or exploits workers that have no rights.
<wpwrak> murphy never rests :)
<wpwrak> well, you always have to choose between mainstream processes and alternative/customized processes. like with injection molding :)
<wolfspraul> I think we have a chance with that because our stability and value comes from continuity in free software, not in how well we exploit nature or people.
<wolfspraul> I think you see this too black & white.
<wpwrak> no, it's all shades of grey
<wolfspraul> the 'mainstream' people are very aware of 'alternative' processes
<wolfspraul> at least the ones I've met
<wolfspraul> there is no mainstream or alternative, it's just a lot of processes to pick from, and it depends on the customer which one is best
<wolfspraul> wpwrak: have you ever met Nico in Taipei?
<wolfspraul> if we ever have money again, we'll meet up with him and he can take us through a tour of his mechanical supply chain. Very cool!
<wpwrak> i think so, yes. but only briefly and i think it was around the time openmoko went down.
<wolfspraul> he loves to take people to 'his' shops that supply him with stuff
<wpwrak> hehe :)
<wolfspraul> he constantly works with 20-30 suppliers, all sorts of different materials and processes, and optimizations
<wolfspraul> there's no 'mainstream' or 'alternative' there
<wolfspraul> it all depends on customer, requirements/priorities, target unit cost, materials, etc.
<wolfspraul> mechanical supply chain is a very diverse set of companies
<wpwrak> maybe. but i'd still expect them to cover only a small subset of all feasible choices. and some of the uncovered ones may be actually work but have no nice migration path from the ones they cover.
<wolfspraul> btw, one math works like this: 1/3rd electricty, 1/3rd material, 1/3rd people
<wpwrak> that much on electricity ?!?
<wolfspraul> so when comparing Taiwan and China, for example, material is the same, people cheaper in CHina, electricity cheaper in Taiwan
<wpwrak> you have E = m. what happened to E = mc^2 ?
<wolfspraul> yes, 'one math', probably depending on process (forgot which one exactly this was)
<wpwrak> maybe aluminium production :)
<wolfspraul> his supply chain of course also extends into China, it's all case by case where the companies are, who is better suited or optimized (invested) for a particular process
<wolfspraul> no no
<wolfspraul> ask roh about how much electricity costs for the lasering of just those 80 units
<wolfspraul> keep in mind: others optimize too
<wpwrak> (electricity cheap in taiwan) interesting. having seen suzhu at night, i would have thought it had negative cost over there :)
<wolfspraul> Taiwan gets most electricity from nuclear power plants
<wolfspraul> China is very different, electricity prices in CHina are political (different companies paying totally different amounts)
<wpwrak> yeah, from what else :)
<wpwrak> (china) nice way of taxation :)
<wolfspraul> but from Nico's numbers, he said the companies he looks at pay more in China than in Taiwan. Which sounds plausible to me.
<wolfspraul> those are mostly small private companies, they will pay a higher rate to subsidize inefficient state companies
<wolfspraul> let's ask roh later how many kWh he thinks are needed for the lasering of the 80 m1 cases. I'm curious :-)
<roh> re
<roh> kWh? no clue
<roh> but in money i would say neglible compared to material and manufacturing cost (machine runtime)
<roh> as soon as we do 80 cases/month i should buy my own bigger lasercutter
<roh> maybe we can also retrofit ours with better lenses (seems to be the main issue)
<roh> our lasercutter needs something like 100-230W of input power
<roh> i think the big one and cooling is also <500W.
<roh> if its running for 14hours it will eat 7kwh. but if you take the controlling pc into account and its monitor...
<wolfspraul> nah, it's all small
<wolfspraul> understood
<wolfspraul> no 1/3rd here :-)
<roh> you can save more electricity by using a notebook or disabling the monitor than anything else ;)
<wolfspraul> I would be seriously interested in design improvements that remove the need of the metal sheet, but workload is overwhelming for me right now, so I cannot do it.
<roh> even if it would be 1kW instead of 1/2 ... i mean.. one kWh is <23cent for '100% regenerative energy (green electricity).. means 2E ;)
<roh> wolfspraul: lets fix the latest reworks into a rc4 successfully first  ;)
<wolfspraul> yes understood, insignificant part of the cost in our run
<roh> the metal sheet is less headache than the buttons for sure.
<wolfspraul> true
<wolfspraul> buttons are worst, then metal sheet
<wolfspraul> agreed?
<roh> yes
<roh> third is tolerances on acryllic.
<wolfspraul> but getting rid of the metal sheet may be hard work, if it's done inside the pcb, i.e. without insulation patches on the pcb
<wolfspraul> on the tolerances I think one thing you don't really factor in right now is that in a larger run, you don't need to design in such a way that any set of parts fits
<wolfspraul> in other words, the tolerances may even themselves out
<wolfspraul> you just produce say 100, and then sit down trying to find set that fit, and you accept that you will have a small percentage of leftover parts at the end
<wolfspraul> that's a different way to deal with the tolerance problem
<wolfspraul> in a larger run, the stuff I've seen, you don't produce every part to be within perfect tolerances
<wolfspraul> that's just not economical, because even a hardened steel tool will wear out
<wpwrak> roh: (acrylic tolerances) are they in the raw material or the laser cutting ?
<wolfspraul> so you just produce, and then sit down to find matching parts :-)
<wolfspraul> of course that assumes a certain labor cost, often around 1 EUR / hr
<wpwrak> small detail ;-)
<wolfspraul> yes sure, all the optimizations connect to those things though, it's all connected
<wolfspraul> if you change some costs, suddenly the 'best' process may change too
<wpwrak> that much about not wanting a process that relies on exploitation :)
<wolfspraul> I've just learnt: electricity costs in acrylic lasering are insignificant. need to keep that in mind...
<roh> wpwrak: raw material
<wolfspraul> correct, that adds another requirement into the process
<wolfspraul> I'm not saying 1 EUR / hr is exploitation btw, I said what bugs me is lack of worker rights.
<wpwrak> of course, the alternative is automation, which simply eliminates all those exploiting jobs :)
<wolfspraul> no, wrong. please think about the tolerance problem more.
<wolfspraul> you cannot have it all ways
<wolfspraul> 'optimizations' means to optimize along certain angles. you always 'exploit' something as part of the optimization.
<wolfspraul> that's just unrealistic. I think we really want to produce something in our lifetime...
<wpwrak> roh: surprisingly large tolerances
<roh> its not only something to counter with time. tolerances produce nonuseable parts if too big
<roh> especially as long as we use slots anywhere
<roh> wpwrak: yeah
<wolfspraul> if you buy material with 'less' tolerances, you just push the problem out of your sight potentially
<roh> too bad i havent gotten plexiglas XT in colored as default yet. will see if i can get it next time
<wolfspraul> they throw away for you, and you pay for it :-)
<wpwrak> well, you could buy sheets that are thicker than you need and machine them to narrow tolerances ;-)
<wolfspraul> assuming your machine can do that, yet
<wolfspraul> yes
<roh> for lasering XT should behave nearly the same. only milling isnt as great
<wolfspraul> but if that would be easy, someone else would have done it already
<roh> we'll see.
<wpwrak> wolfspraul: (machining) i think you'd cloud the surface
<larsc> wpwrak: that is an interesting though. the alternative to exploitation would be no jobs at all.
<wolfspraul> optimization = exploitation
<wolfspraul> just what :-)
<wolfspraul> I have no problem with low hourly wages, but I want the people we work with to have the right to say 'no', and to have realistic alternative paths for themselves. If that's the case I happily work with someone making 1 EUR / hr, even if that's an exploitation from the perspective of someone making 20 EUR / hr.
<wolfspraul> the best is to exploit software of course
<wolfspraul> which is what we mostly try, I think, and why we are optimistic
<wolfspraul> who sheds a tear for letting a CPU iterate over a stupid process indefinitely
<wolfspraul> if I see how Werner exploits his mill, oh my... :-)
<larsc> well, there is a difference between people and tools
<wolfspraul> yes, so when we optimize processes, we shouldn't exploit our environment (dump waste), or rights of people. those 2 are off limits, everything else can be optimized, I think.
<wolfspraul> we can add animal rights, but I don't think we are planning to use trained monkeys in the mechanical supply chain :-)
<qi-bot> [commit] Werner Almesberger: cad/test1/Makefile (cadmium.stl): corrected typo in file name (master) http://qi-hw.com/p/wernermisc/7a39c5e
<qi-bot> [commit] Werner Almesberger: mm1rc3rst/fix2.sch: changed diode symbol to from regular to Schottky (master) http://qi-hw.com/p/wernermisc/fe20d74
<larsc> maybe we could use them to write code
<wpwrak> larsc: or solve captchas ;-)
<larsc> i fear that wouldn't get us anywhere
<tuxbrain_away> wpwrak: good job with the CAD comparative dude :) good material to make an interesting post :)
<wpwrak> tuxbrain_away: thanks ! :) not quite done yet, though. i found some more interesting details. will update soon.
<tuxbrain_away> better than update make a second chapter :)
<wpwrak> (chapter) yeah, and maybe convert to LaTeX ;-)
<tuxbrain_away> (I hate you)
<tuxbrain_away> I will try LyX then , as LaTeX IDE :)
<wpwrak> i have a little perl script that translates TeX (don't remember if it's plain TeX or LaTeX) into ascii ... :)
<wpwrak> it's LaTeX. quite advanced for its time. i wrote that beastie in 1994 :)
<tuxbrain_away> man, there is  anything that you haven't done? How many people compose Werner? I don't believe you are only one person
<qi-bot> [commit] Werner Almesberger: cad/test2/button.py: Cadmium version without artifact prevention (master) http://qi-hw.com/p/wernermisc/83ddf11
<qi-bot> [commit] Werner Almesberger: cad/: added description to 2nd series of tests and a pointer from the 1st series (master) http://qi-hw.com/p/wernermisc/8ad6df6
<kristianpaul> wpwrak: bogota, right, but afortunatly mail delivery is very fast :)
<kristianpaul> s/afortunatly/fortunatly
<wpwrak> grmbl. meshlab crashed by pc :-(
<qi-bot> [commit] Werner Almesberger: cad/test2/: copied original version of sources from cad/test1/ (master) http://qi-hw.com/p/wernermisc/70eef56
<qi-bot> [commit] Werner Almesberger: cad/test2/button.py: removed "epsilon" and "noise" (master) http://qi-hw.com/p/wernermisc/4296080
<qi-bot> [commit] Werner Almesberger: cad/test*/button.scad: remove definitions related to the pusher, not used here (master) http://qi-hw.com/p/wernermisc/8ca4b01
<qi-bot> [commit] Werner Almesberger: qpkg/: committed some old changes (non-functional) (master) http://qi-hw.com/p/wernermisc/326cd33
<kristianpaul> 11:31 < azonenberg> http://colossus.cs.rpi.edu/~azonenberg/images/homecmos/2011-07-22/S7301551.JPG is a 40x die overview after the final KOH wet etch and mask strip (so what  you're seeing is all Si except for a bit of some brownish precipitate in the lower parts of the etched areas)
<solrize> yow, shipping 1 nanonote to the US costs almost $40 and thats for the slow option :(
<kristianpaul> :(
<kristianpaul> yeah,
<wpwrak> solrize: get more than one, then the per unit shipping cost drops ;-)
<kristianpaul> solrize: to compesate you i think is 60usd to my country..
<kristianpaul> so 40 is not that bad..
<solrize> wpwrak, yeah i asked around a little if anyone else near me wanted one
<solrize> i suggested them to sparkfun.com
<solrize> unfortunately there's no apparent quantity discount
<wpwrak> a distributor in the US would certainly be useful
<wpwrak> you'd have to ask wolfgang at what quantities he would consider a discount
<kristianpaul> indeed
<kristianpaul> ask Yi
<kristianpaul> yi@sharism.cc
<solrize> hmm
<wpwrak> solrize: do you have taxes / customs feeds that get slapped on this kind of imports ?
<wpwrak> e.g., in argentina, taxes/fees usually amount to about 40-50%
<solrize> wpwrak, hmm, there is theoretically a duty charge of a few dollars but u.s. customs rarely bothers stopping packages
<wpwrak> some of them are based on the cost of the goods plus the shipping cost. so the real cost of the shipping is actually a bit higher than what gets paid to fedex or such
<solrize> i buy stuff from dealextreme.com all the time, they just send it in the normal post
<wpwrak> lucky you :)
<solrize> fedex may be collecting duty charges
<kristianpaul> yeah
<kristianpaul> same here (DX)
<solrize> might be 10% or so
<kristianpaul> and no TAX?
<kristianpaul> wow
<kristianpaul> nice
<wpwrak> sigh. the easy life :)
<wpwrak> kristianpaul: here in south america, we're wealthy, aren't we ? we can afford high taxes ;-)
<kristianpaul> even 10% is lower than fedex handling/tax/ here.. wich is kinda 40%
<kristianpaul> wpwrak: we're rich countries :_)
<solrize> customs might stop a DX package (you get a notice saying you must pay $N duty to get the package) but i've never had it happen
<kristianpaul> very rare indeed
<kristianpaul> DX is develiver by USPS isnt?
<solrize> kristianpaul, yeah, international post
<kristianpaul> btw a bit OT bit how long take to deliver to you?
<solrize> DX?  about a week
<kristianpaul> wow
<kristianpaul> yes
<solrize> hmm maybe thats optimistic
<solrize> 1-2 weeks say
<solrize> it varies
<kristianpaul> here is a month or so,
<kristianpaul> yeah
<wpwrak> fees/taxes collected by customs are usually collected by the deliverer, be it the fedex/dhl/ups/etc. guy or the postman
<kristianpaul> solrize: so you can be a distributor in the US
<wpwrak> you'd only have to go to customs if they find some issues or if the carrier doesn't want to prepay the charges
<solrize> kristianpaul, i'm not set up for that, it's better for a retail operation like sparkfun to do it
<kristianpaul> solrize: just sent a couple of small boxes by ground mail from time to time, dint hurt
<kristianpaul> had you seen how sparkfun started? :-)
<kristianpaul> so you asked sparkfun to sell nanonotes? :-D
<kristianpaul> nanonote*
<solrize> i dunno but they started by wanting to be retailers, i bet ;)
<solrize> yeah i suggested that to them
<kristianpaul> and replied?
<solrize> no reply yet, i suggested last night and its weekend here now
<kristianpaul> sure sure
<wpwrak> regarding discounts, some margin would already come from avoiding shipping individual units. e.g., if you order 20, you'd probably still pay about the same amount. but you'd then have much cheaper and faster domestic shipping. that alone may yield a margin of 20-30%.
<wpwrak> (weekend) that's when people work more efficiently, right ? ;-)
<solrize> web site doesn't allow ordering more than 9 ;)
<kristianpaul> solrize: ask yi for 10 and beyond :-)
<solrize> yeah i saw that.  i could imagine buying 2 but thats about it ;)
<wpwrak> solrize: they had a 10 pack. maybe that's where the limit comes from. but i'm sure they'll be more than happy to send you up to a few hundreds ;-)
<wpwrak> the limit may be around 600, which is when more units would have to be produced :)
<solrize> they don't sell replacement batteries either
<kristianpaul> no need
<kristianpaul> is generic
<solrize> there is a chart of almost-compatible batteries
<wpwrak> there's a list of commonly available batteries you can use instead. much more efficient than ordering from abroad.
<solrize> but i wish they'd tweak the plastics so a standard phone battery would fit properly
<solrize> yeah i saw
<kristianpaul> i buyed a Nokia BL-4C  clone and worked fine
<wpwrak> yes, the case isn't exactly right for them
<solrize> "The battery is just a little too short. A small object like a piece of paper is needed to make sure it doesn't disconnect. "
<solrize> they should use a bigger battery if there's space in the case for that counterweight thing
<wpwrak> that's not easy to solve, though. the case design isn't owned by sharism and in any case, changing the case shape would require a new mold, which is pricy
<solrize> hmm
<wpwrak> (counterweight) ;-))) that one's a little tricky, though
<solrize> we have a molded thing where i work, the mold costs around 7500 usd
<solrize> which i guess is a lot for a low-qty thing like that
<wpwrak> yeah. would be difficult to recover such a price
<wpwrak> how complex is your mold ? and what is it made of ? steel ?
<qi-bot> [commit] Werner Almesberger: cad/test2/button.scad: added overlaps to eliminate artefacts at coincident faces (master) http://qi-hw.com/p/wernermisc/521f031
<qi-bot> [commit] Werner Almesberger: cad/test2/README: added more results and cleaned up the text (master) http://qi-hw.com/p/wernermisc/3f820dc
<kristianpaul> one day lost because and input that should be output..
<solrize> pretty simple mold i guess.  it's probably steel, i don't know
<solrize> cnc machine
<solrize> we have a tabletop cnc mill at my hackerspace
<solrize> i wonder how hard it is to mill injection molds
<kristianpaul> wich its name is? :-)
<solrize> noisebridge.net
<solrize> you know him?
<kristianpaul> nope :p
<kristianpaul> btw you work with FPGA's as well, already aware of Milkymist project i guess
<kristianpaul> ?
<solrize> i've been interested in fpga's but no one at noisebridge is using them afaik
<solrize> lots of AVR stuff though
<solrize> yeah i've heard of milkymist
<solrize> but it uses a proprietary xilinx chip doing who knows what
<solrize> i'd like to make a completely free microprocessor
<kristianpaul> ASIC?
<solrize> http://cmp.imag.fr/  yeah less expensive than i'd have expected
<kristianpaul> ah, checkout #homecmos then :-)
<solrize> oh neat
<kristianpaul> well, you can implement milkymsit soc, in those ASICs, or atleast the lm32 core..
<solrize> i don't really have any interest in video devices so i didn't look at milkymist very much... i wish qi would make an audio player/recorder
<solrize> i want to run rockbox on the nano so i can use it as an audio player
<solrize> so i can listen to music while i code
<kristianpaul> neither me, but is a nice project and the SoC works
<solrize> cool
<kristianpaul> i think you can run gmu in a separate tty
<solrize> whats gmu?
<solrize> well anyway there's some music apps
<wejp> yes, you can, you can start gmu and then switch to another terminal to do other stuff
<solrize> rockbox is really nice and runs on android and maemo now
<solrize> porting shouldn't be too hard
<wejp> or you could simply use gmu
<solrize> yeah i guess so
<solrize> is there ever gonna be a YA nanonote?
<wejp> noone really knows ;)
<wpwrak> we hope but we don't know
<wejp> yeah
<solrize> any interest in making an audio player?  all existing ones suck ;)
<wpwrak> one problem with audio is that you can't support the more popular formats without getting into patent issues
<wpwrak> that is, unless you wait a bit longer, until the patents expire
<solrize> ogg is fine
<solrize> it can run rockbox or gmu or whatever
<solrize> so people can compile mp3 into it if their jurisdiction allows it ;)
<wpwrak> people compiling mp3 into it is tricky. if you as maker/distributor/etc. much as hint at the possibility, you can still get in trouble
<wpwrak> s/much/as much/
<solrize> well rockbox has mp3 and no one has had problems afaik
<roh> solrize: nobody makes money with it.
<solrize> i'm fine with a vorbis-only player
<solrize> vorbis and flac that is
<solrize> actually flac-only is fine
<solrize> any mp3 builds would be up to the user groups ;)
<wpwrak> the players for which rockbox is written probably already support mp3. so a license is already paid. presumably not one that allows that sort of firmware change, but it may be considered of insufficient interest to argue the fine points in court
<solrize> true... there is a guy making a custom hw rockbox player (that sucks for audio) but he's small enough that no one has hassled him
<wpwrak> that's a bit the problem. as long as you're too small and only lose money, nobody will trouble you. but as soon as success seems within reach, the parasites will come ...
<solrize> true
<solrize> how hard/expensive is it likely to be to make a player? main cost would be molds
<solrize> the guy making the custom player uses 3d printing
<wpwrak> yeha, i don't know yet how costly that part would be
<wpwrak> mechanical engineering is something we're still just beginning to touch in qi-hardware
<wpwrak> so far, the greatest achievements are my wooden molds for casting the counterweight and the laser-cut acrylic case for M1. the latter is actually already almost at a professional level. but it's also a solution with somewhat limited applicability.
<solrize> a simple box with some connector holes and a battery door would be fine... maybe there's one in a catalog
<solrize> reprap is ok for cheesy prototypes
<solrize> hackerdojo.com (another hackerspacei visit) has a professional level 3d printer
<solrize> but i've never used it
<wpwrak> yes, if you can find an already existing case, that would help
<solrize> altoids ;)O
<wpwrak> yeah :) also excellent shielding :)
<solrize> i guess it doesn't need any UI (no screen or buttons). just an on/off switch and bluetooth to control it from a phone ;)
<solrize> wpwrak, were you involved with openmoko?
<wpwrak> yup, i was. a bit of hacking and occasional forays into hardware
<kristianpaul> there is way to hold the samplin in a scope, after triger the signal right... well may be not in this one..
<wpwrak> kristianpaul: you mean setting the trigger mode to "single" (as opposed to "auto" or "normal") ?
<kristianpaul> yes, i'm using single right now
<wpwrak> so is that what you were looking for ?
<kristianpaul> yes, ;)
<wpwrak> problem solved. that was easy ;-)
<kristianpaul> not yet, well the main problem not, here we go again 15m of sinthesis..
<wpwrak> ;-)
<viric> wpwrak: have you seen fabfi?
<wpwrak> no, haven't seen that one yet ...
<viric> open source wireless with components made from trash
<wpwrak> nice distances - 6 km :)
<wpwrak> seems a bit bulky, though
<viric> :)
<kristianpaul> 6 km, well i can stand on the bulk :-)
<viric> they pick access points from the trash though
<viric> these afgans are getting too clever. US is not spending enough effort
<kristianpaul> ha, where you can find access points in the trash?..
<kristianpaul> i mean.. not bad for then
<kristianpaul> one of the missing things in mm soc, for sure a smarter wishbone bus.. ar least one that not freeze the cpu because a delayed or ausent ack signal after non proper termination of a bus cycle..
<kristianpaul> i hope i'm wrong but i'll see
<wpwrak> solrize: btw, when you make CAD models for printing/fabbing/casting, what programs do you use ?
<kristianpaul> hell 32° C
<kristianpaul> where is the wind..
<wpwrak> kristianpaul: can you please send 5 C down to argentina ? :)
<kristianpaul> hum scope ch2 got biased from a pulse signal in the ch1...