Business models for having a PnP

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bootstrap
 
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Re: Business models for having a PnP

Post by bootstrap »

ktownsend wrote:
mikeselectricstuff wrote:The other big issue is that for short-run jobs is setup time gets significant, and unless everything is on reels it gets fiddly - even then if you don't have enough feeders you spend a lot of time reloading them for different jobs. Not to mention setting up and cleaning stencils...
Another aspect is that as soon as you start doing work for other people you take on risks of bad boards, wasted parts etc.
After a few weeks of having my own pick and place, that's pretty much my own thoughts reading this thread. It just isn't worth the hassle to me. Because I can't afford 50 reels, I find myself optimising my designs to a certain number of common components that I always leave on the machine. It takes me about 3-4 hours to program a board in and run through one or two test runs to make sure everything is setup properly, ASSUMING that I already have proper, tested part definitions for all the components (which means pouring over every datasheet for evey chip, connector, etc.). It's a lot more work than just pressing the 'assemble' button, not to mention dealing with the solder paste and cleaning stencils, etc. Large ICs are actually the least work ... it's all those discretes that take forever since you need to verify the package dimensions on all of them, etc. Unless someone was using the same parts as me, I just can't see it being worthwhile to offer any sort of assembly service. It's fabulously boring, manually-intensive work and it isn't that much fun to do it for yourself ... I can't imagine anyone happy doing it for someone else for a couple hundred dollars given the amount of time and effort involved.
Then I'm guessing you bought a pick-and-place so you can make PCBs with QFNs and BGAs, right? Otherwise, why bother? I mean, you said it yourself... it takes "forever" to program the PaP, verify all the parts footprints are correct, load the feeders, fiddle with special-case issues, and so forth.

This is exactly my reasoning... I need to be ABLE to design with 0201s, QFNs, BGAs, and the PCBs need to WORK once assembled (read: be placed correctly). I'd be totally happy to hand assemble my PCBs with hot-air-bath, PCB-cradle, hot-air-pencil and such. In fact, I'd be thrilled, because it would save me $40,000 or so (it appears).

Your comments make perfect sense to me. That's why I considered the "shared machine" idea, and shy away from anything else (other than rare, super-quick (overnight), high-paying "emergency" jobs for [probably only local] folks who "need it now... no matter what"). As you say, $200 just isn't worth it, and $2000 maybe is barely worth a day or two, as long as it doesn't have any lingering "issues".

One very limited opportunity (to perhaps make a few bucks on the side, but not a "real" business) would be to offer a service that ONLY assembles QFN, BGA, CSP and a limited selection of very standard 0201, 0402, 0603, 0805 components onto PCBs. The idea is, these are the ONLY components that prevent a huge number of people from building their own PCBs (or designing with these kinds of components). Especially if the customers only supplied their QFNs and BGAs, and were required to buy the standard 0201 ~ 0805 caps and resistors this service would always have in quantity (and always stay mounted on the pick-and-place machine).

But yeah, except for some very narrow, special situations, I wouldn't even consider being in the PCB assembly business. Well, I say that without having the equipment yet, but your point of view makes sense to me just from the reading I've done.

You have the MDC-7722 also? How much did it cost? And how much more did you pay for other accessories and feeders?

scsi
 
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Re: RE: Business models for having a PnP

Post by scsi »

bootstrap wrote:I guess the main question is... what kind of built-in precision do they have [over short distances]. The problem is, even if they exactly sync the pick-and-place-head against a fiducial mark or via on the PCB... they might instantly void that precision the moment they move the head, unless they have linear encoders on the X,Y tracks. Anything with gears, belts or other schemes between the pick-and-place head and the encoders (or stepper motors in my nightmares) can go out of sync even before it moves the head 0.001" due to drive-train backlash.
I believe that backlash can be worked around by always approaching the target position from the same direction, which is the case in PnP application. I think what is more important is the repeatability and not the accuracy of the movement. If repeatability is good, all you need is to program the proper offset between the cameras and nozzles and simply ignore the backlash.

-scsi

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ktownsend
 
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Re: Business models for having a PnP

Post by ktownsend »

bootstrap wrote:Then I'm guessing you bought a pick-and-place so you can make PCBs with QFNs and BGAs, right? Otherwise, why bother? I mean, you said it yourself... it takes "forever" to program the PaP, verify all the parts footprints are correct, load the feeders, fiddle with special-case issues, and so forth.
It takes me a couple hours, but I bought it because I generally need to make about 50 boards at a time. Outsourcing assembly usually only becomes cost effective for me at 250+ boards, but then there are still a lot of one-time expenses like stencils, etc., and needing to buy 250 of every part ... which can get pricey if you really are only confident you'll sell 50 this quarter. I can easily hand place 10 boards, but it's horrible dull and the amount of time involved destroys any real profitability. Even if you don't place BGA ... there's a strong case to be made for purchasing a PnP if you have regular requirements for boards in the 50-100 quantity range, and support a number of designs with thos quantiites. I'd say even with setup times, I can assemble boards about 8-10x faster than before overall. It's still not fun, but at least it starts to be financially sane if I attach any value to me time.
bootstrap wrote:This is exactly my reasoning... I need to be ABLE to design with 0201s, QFNs, BGAs, and the PCBs need to WORK once assembled (read: be placed correctly). I'd be totally happy to hand assemble my PCBs with hot-air-bath, PCB-cradle, hot-air-pencil and such. In fact, I'd be thrilled, because it would save me $40,000 or so (it appears).
I bought it having BGA placement in mind (you can still hand-place QFN), particularly because most ARM9 chips are BGA only. But this actually isn't the driving factor for me ... It's all about the small (but not small enough) volume, and finding a way to efficiently assemble those quantities of boards without very heavy investment in expense parts/stock. The 400€ a month the PnP costs me is quite small compared to the €1200 per boards in assembly costs + parts for 250 boards I would otherwise need to fork out. In that sense, a "shared" machine makes sense, but the idea would kind of scare me personally since for the amount of money involved I'd worry about how that investment would work out longer term. I'd really need to trust the other people or have a safe structure setup on the time sharing, and perhaps some sort of insurance, etc..
bootstrap wrote:You have the MDC-7722 also? How much did it cost? And how much more did you pay for other accessories and feeders?
Yes. With the Euro jumping off a cliff, it actually cost me a lot more than it would have a few months ago, but I got a good price on it since I usually go several times a year to Tokyo and know the director of the company that makes them (thanks to an introduction from a Japanese engineer friend). The reels are what adds up, and are what really determines the overall cost since the machine price itself is farily fixed. I currently only have 12x8mm reels, 2x12mm reels, and 15x8mm cut tape and 4x12mm cut tape. Anything 16mm and higher can be placed without feeders using double-sided tape and programming the parts in as trays. I could use at least 7-8 more 8mm feeders, but they add up and my budget was already strained. As I pick up some business, though, I'll try to work up to 20x8mm and 3x12mm which fills up one side of the machine (27 8mm reels on each side), and use cut tape for any oddball discretes/small parts. The cut tape is annoying since the parts jump out if you bump the tray, but it's still the cheapest solution in the short term. 20 8mm feeders should be ideal for my own needs.

Unfortunately, you'll probably have to go through a distributor to buy the machine which adds some margin, though I suppose it also assures you of a local warranty/repair facility as well. I'd try to negotiate a lot on the reels, though, since that's where most of the margins tend to be from most companies (with any PnP).

A big factor for me deciding on the 7722FV is that I know there are numerous other people here with the same (or similar) machines. For a small scale company like my own, that's a pretty big plus when you can bounce questions off other people, and share your experiences/parts/etc. The other big factor (aside from budget) was just physical size. The 7722FV it big, but not so big that it can't fit in a small office or apartment. It's very 'movable' with two people and fits on a table unlike some massive industrial beasts that require much larger office facilities.

bootstrap
 
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Re: RE: Business models for having a PnP

Post by bootstrap »

scsi wrote:
bootstrap wrote:I guess the main question is... what kind of built-in precision do they have [over short distances]. The problem is, even if they exactly sync the pick-and-place-head against a fiducial mark or via on the PCB... they might instantly void that precision the moment they move the head, unless they have linear encoders on the X,Y tracks. Anything with gears, belts or other schemes between the pick-and-place head and the encoders (or stepper motors in my nightmares) can go out of sync even before it moves the head 0.001" due to drive-train backlash.
I believe that backlash can be worked around by always approaching the target position from the same direction, which is the case in PnP application. I think what is more important is the repeatability and not the accuracy of the movement. If repeatability is good, all you need is to program the proper offset between the cameras and nozzles and simply ignore the backlash.

-scsi
I'd be surprised if someone could make such a scheme work reliably in practice, but certainly the only proof one way or another is actual performance of physical machines.

scsi
 
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Re: RE: Business models for having a PnP

Post by scsi »

bootstrap wrote:
scsi wrote:I believe that backlash can be worked around by always approaching the target position from the same direction, which is the case in PnP application. I think what is more important is the repeatability and not the accuracy of the movement. If repeatability is good, all you need is to program the proper offset between the cameras and nozzles and simply ignore the backlash.

-scsi
I'd be surprised if someone could make such a scheme work reliably in practice, but certainly the only proof one way or another is actual performance of physical machines.
Agree. Unfortunately I cannot verify Madell's claims about 0.001" positioning accuracy. Typically it takes a good precision ground ballscrew to get to this kind of backlash and they are quite expensive. On the other hand Madell is using THK linear rails, which are one of the most expensive out there.

My machine is built on top of a super precision gantry system from Anorad and runs on linear motors with 0.1um encoders. Cannot verify backlash workaround theory here either... :)

-scsi

bootstrap
 
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Re: Business models for having a PnP

Post by bootstrap »

ktownsend wrote:It takes me a couple hours, but I bought it because I generally need to make about 50 boards at a time. Outsourcing assembly usually only becomes cost effective for me at 250+ boards, but then there are still a lot of one-time expenses like stencils, etc., and needing to buy 250 of every part ... which can get pricey if you really are only confident you'll sell 50 this quarter. I can easily hand place 10 boards, but it's horrible dull and the amount of time involved destroys any real profitability. Even if you don't place BGA ... there's a strong case to be made for purchasing a PnP if you have regular requirements for boards in the 50-100 quantity range, and support a number of designs with thos quantiites. I'd say even with setup times, I can assemble boards about 8-10x faster than before overall. It's still not fun, but at least it starts to be financially sane if I attach any value to me time.
This raises another question I need to answer to rationally decide whether to buy a pick-and-place machine now (versus when production starts, or perhaps "never" if BANNED assembly is more practical "all things considered"). That is, *roughly* what kind of costs can I expect to have batches of 250 to 1000 large PCBs made (6" square with 300 total components) along with batches of 1000 to 4000 small PCBs (3" square with 50 total components)? What would you guess my costs per PCB would be for those two PCBs?

Also tell me anything you can about the relative advantages and disadvantages of trying to get production in asia versus a western country (of the modest quantities that we need). My back of the envelope calculation implies $3 to $6 each for my larger PCB if done with my own pick-and-place machine (not counting ?my? labor to keep an ear on the machine, assuming we can "hear" sounds or interruptions when human attention is required).

One more question. Even these modest speed machines that claim about 2000 parts per hour tend to have much faster rates to place solder-paste on pads (typically, 10,000 pads per second). This makes total sense, since the average motion required between pads is infintesimal compared to picking up new components. I went to see a small company near me that has two similar size pick-and-place machines, and they claimed they can trace a rather large percentage of problems with assembled PCBs to imperfect solderpaste application (which they do with a rather expensive solderpaste stencil printer). Thus, if it is more reliable to place paste on every pad of PCBs before placing components, that seems attractive to me --- in theory. What do you think about this issue "in practice"?
I bought it having BGA placement in mind (you can still hand-place QFN), particularly because most ARM9 chips are BGA only. But this actually isn't the driving factor for me ... It's all about the small (but not small enough) volume, and finding a way to efficiently assemble those quantities of boards without very heavy investment in expense parts/stock. The 400€ a month the PnP costs me is quite small compared to the €1200 per boards in assembly costs + parts for 250 boards I would otherwise need to fork out. In that sense, a "shared" machine makes sense, but the idea would kind of scare me personally since for the amount of money involved I'd worry about how that investment would work out longer term. I'd really need to trust the other people or have a safe structure setup on the time sharing, and perhaps some sort of insurance, etc...
You say the PaP costs you 400€ per month. Is that because you took a loan to buy it, and that's your monthly payment (or you leased it)? Or you bought the machine, and 400€ is how you calculate amortizing the machine across n years of predicted work?
bootstrap wrote:You have the MDC-7722 also? How much did it cost? And how much more did you pay for other accessories and feeders?
Yes. With the Euro jumping off a cliff, it actually cost me a lot more than it would have a few months ago, but I got a good price on it since I usually go several times a year to Tokyo and know the director of the company that makes them (thanks to an introduction from a Japanese engineer friend). The reels are what adds up, and are what really determines the overall cost since the machine price itself is farily fixed. I currently only have 12x8mm reels, 2x12mm reels, and 15x8mm cut tape and 4x12mm cut tape. Anything 16mm and higher can be placed without feeders using double-sided tape and programming the parts in as trays. I could use at least 7-8 more 8mm feeders, but they add up and my budget was already strained. As I pick up some business, though, I'll try to work up to 20x8mm and 3x12mm which fills up one side of the machine (27 8mm reels on each side), and use cut tape for any oddball discretes/small parts. The cut tape is annoying since the parts jump out if you bump the tray, but it's still the cheapest solution in the short term. 20 8mm feeders should be ideal for my own needs.

Unfortunately, you'll probably have to go through a distributor to buy the machine which adds some margin, though I suppose it also assures you of a local warranty/repair facility as well. I'd try to negotiate a lot on the reels, though, since that's where most of the margins tend to be from most companies (with any PnP).
Yeah, sorry to hear about the euro pain. Just a few months earlier and the dollar was poopoo and the euro was king. Chalk up another one to Murphy and his Law. Pretty soon no self-respecting company will accept anything but gold for their goods (if they're smart). I just noticed manncorp sells that machine for $30,000 US, which I guess is roughly €25,000... without feeders and options, presumably. But I guess that model inherently comes with top and bottom (2-camera) vision, at least. This is almost exactly what APS Novastar charges for the LE40V that catches my fancy so far (though the MD2277 is a close second in my book, not even counting this website and forum). I think the MD2277 can handle larger PCBs (the LE40V only handles 340mm x 560mm PCBs), but I also guess the footprint of the LE40V is probably quite a bit smaller (1016mm x 1067mm x 686mm high)... and can thus sit on a desk, countertop (or industrial strength table) instead of the floor. Otherwise, they're probably fairly similar, I'm guessing.

Woops! I just checked, and I have it backwards! And WOW, the videos on the internet make the 7722FV look HUGE, but the specifications at manncorp claim its footprint is only 710mm x 760mm x 660mm (high) - which is quite a big SMALLER than the LE40V unit I'm looking at. Wow is that a surprise! All the videos make it appear HUGE, and they all make it appear it sits on the floor. But obviously not.

Okay now that I have both specs in front of me, they are even more similar than I thought. I'm rather blown away that the 7722FV (at least on manncorp webpage) claims 0402 is the smallest supported component (versus 0201 for the LE40V). The claimed placement accuracy of 7722FV is 0.10mm with flying vision and 0.05mm with bottom camera (which I thought was standard equipment, but I guess not). This compares to 0.025mm for the LE40V. Gads, the LE40V is a BEAST - it weighs twice as much as the 7722FV (113kg versus 60kg). The LE40V web-page and product brief PDF don't even say how many feeders it takes (maximum).

Interestingly, even though the 7722FV says its placement accuracy is 0.05mm (at best), it claims its "X,Y resolution" is 0.015mm. I guess some precision is lost between the X,Y linear encoders and the pick-and-place head --- either flexure, incomplete compensation for thermal expansion, or limitations of the bottom-up (and/or top-down) vision system. Just guessing. Their placement rates are not stated the same way, but seem similar. I was also wrong about maximum PCB sizes, which are 390mm x 310mm for 7722FV versus 560mm x 343mm. At first that seemed totally irrelevant since my largest PCBs are less than 150mm square --- but then I realized panels of PCBs might be a wise move when production time arrives (that can easily cover a panel of 6 of my large PCBs and 28 of my small PCBs... hmmmm). But then I need some way to "de-panelize" them after assembly, which sounds rather unpleasant.

Overall, that makes them seem fairly close. As it turns out, the 7722FV is smaller and lighter, which comes in handy when locating it and moving it... but might be partly responsible for not being as rigid - which shows up as slightly lower placement accuracy... IN THEORY (who knows how honest either set of specifications is). The LE40V comes with a standard "automatic 4 position nozzle changer", but also says the following, which I totally don't understand the meaning of: "automatic tool changer - up to 8 positions". I don't see this topic mentioned in the 7722FV specifications, so I cannot compare this aspect of the two machines. Somehow, I'm guessing the 7722FV manages to handle 0201s, no matter what the manncorp specifications say. Do you know about this? I have a fair number of 0201 capacitors on the opposite side of the PCB from my BGA pads (I have "fill-and-cap" treatment on all BGA pads to support "via-in-pad).

Now all we need (both of us) is to find someone who bought a machine that exploded, and who wants to sell his huge but now-useless set of 256 feeders for $200... or €200. That would make us happy, no? Seems like pick-and-place machines are a little like ink-jet printers - the machines are kept [relatively] inexpensive, but they totally nuke your budget on supplies (feeders and ink cartridges).
A big factor for me deciding on the 7722FV is that I know there are numerous other people here with the same (or similar) machines. For a small scale company like my own, that's a pretty big plus when you can bounce questions off other people, and share your experiences/parts/etc. The other big factor (aside from budget) was just physical size. The 7722FV it big, but not so big that it can't fit in a small office or apartment. It's very 'movable' with two people and fits on a table unlike some massive industrial beasts that require much larger office facilities.
Yup, that's a big plus for the 7722FV. I haven't been able to find a single video of a LE40V... or even one of their other pick-and-place machines on the internet. That makes my analysis more difficult. The only partial compensation is... they're made in the USA and the company is in the USA, so I can call them up easier than a japanese or european company... and much easier than a chinese company (for which the documentation seems to be horrific for these kinds of machines). Probably either of these machines would be fine for me, though I'm still leaning towards the LE40V (mostly due to 0201s and [claimed] placement accuracy).

bootstrap
 
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Re: RE: Business models for having a PnP

Post by bootstrap »

scsi wrote:
bootstrap wrote:
scsi wrote:I believe that backlash can be worked around by always approaching the target position from the same direction, which is the case in PnP application. I think what is more important is the repeatability and not the accuracy of the movement. If repeatability is good, all you need is to program the proper offset between the cameras and nozzles and simply ignore the backlash.

-scsi
I'd be surprised if someone could make such a scheme work reliably in practice, but certainly the only proof one way or another is actual performance of physical machines.
Agree. Unfortunately I cannot verify Madell's claims about 0.001" positioning accuracy. Typically it takes a good precision ground ballscrew to get to this kind of backlash and they are quite expensive. On the other hand Madell is using THK linear rails, which are one of the most expensive out there.

My machine is built on top of a super precision gantry system from Anorad and runs on linear motors with 0.1um encoders. Cannot verify backlash workaround theory here either... :)

-scsi
Man, you have the absolute DREAM PLATFORM for your pick-and-place system! Freaking linear motors and... are you kidding?... 0.10um encoders? Wait a second, I think I misunderstand your terminology. Normally when I see the "u" character, that means microns, as in 1/1000mm. But "um"? What is that? 1/1,000,000 meter (which IS one micron)? So, are the encoders 0.10mm (0.004") resolution, or literally 0.10u (0.000004")? I mean sheesh! 0.10u AKA 0.000004" is 1/5 wave of visible light (the tolerance of diffraction limited optics)! Those are the most amazing linear encoders I've ever heard of, if that's for real.

scsi
 
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Re: RE: Business models for having a PnP

Post by scsi »

bootstrap wrote:
scsi wrote:My machine is built on top of a super precision gantry system from Anorad and runs on linear motors with 0.1um encoders. Cannot verify backlash workaround theory here either... :)

-scsi
Man, you have the absolute DREAM PLATFORM for your pick-and-place system! Freaking linear motors and... are you kidding?... 0.10um encoders? Wait a second, I think I misunderstand your terminology. Normally when I see the "u" character, that means microns, as in 1/1000mm. But "um"? What is that? 1/1,000,000 meter (which IS one micron)? So, are the encoders 0.10mm (0.004") resolution, or literally 0.10u (0.000004")? I mean sheesh! 0.10u AKA 0.000004" is 1/5 wave of visible light (the tolerance of diffraction limited optics)! Those are the most amazing linear encoders I've ever heard of, if that's for real.
Yes, that's 100nm digital resolution and there is no miracles. They perform interpolation from analog sine signal that has 20um period. With proper tuning you can get down to 5nm or even better: http://www.renishaw.com/en/rg2-optical- ... oder--6441

Madell's motion controller cannot handle this resolution as it is limited to 125K steps/sec. I use 200x multiplier in the servo drive to get to some meaninful speeds around 1 m/s.

bootstrap
 
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RE: Business models for having a PnP

Post by bootstrap »

scsi wrote:
bootstrap wrote:
scsi wrote:My machine is built on top of a super precision gantry system from Anorad and runs on linear motors with 0.1um encoders. Cannot verify backlash workaround theory here either... :)

-scsi
Man, you have the absolute DREAM PLATFORM for your pick-and-place system! Freaking linear motors and... are you kidding?... 0.10um encoders? Wait a second, I think I misunderstand your terminology. Normally when I see the "u" character, that means microns, as in 1/1000mm. But "um"? What is that? 1/1,000,000 meter (which IS one micron)? So, are the encoders 0.10mm (0.004") resolution, or literally 0.10u (0.000004")? I mean sheesh! 0.10u AKA 0.000004" is 1/5 wave of visible light (the tolerance of diffraction limited optics)! Those are the most amazing linear encoders I've ever heard of, if that's for real.
Yes, that's 100nm digital resolution and there is no miracles. They perform interpolation from analog sine signal that has 20um period. With proper tuning you can get down to 5nm or even better: http://www.renishaw.com/en/rg2-optical- ... oder--6441

Madell's motion controller cannot handle this resolution as it is limited to 125K steps/sec. I use 200x multiplier in the servo drive to get to some meaninful speeds around 1 m/s.
Wow, this is fabulous. Any idea how much they cost (for a 1-meter long scale)?

Many years ago I made dense rotate encoders --- at great effort, then copied them with ease on a kodak microfilm that had about 0.50u (0.0005mm) resolution. But you're five times finer than that (though perhaps a 2x gain is possible via quadrature decoding). These days, I'd guess they either selectively vapor deposit aluminum on some substrate (glass or some very stable film), or vapor deposit aluminum then etch off 50% with an electron beam... or maybe even chemical etching. Finally they probably vapor deposit [transparent] silicon monoxide or silicon dioxide over the entire mess to make the scale unscratchable. Or something like that.

Anyway, please leave your gantry, linear motors and encoders to me in your will... just in case something terrible happens! Hahahahaha. But really! :-)

scsi
 
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Re: RE: Business models for having a PnP

Post by scsi »

bootstrap wrote: Anyway, please leave your gantry, linear motors and encoders to me in your will... just in case something terrible happens! Hahahahaha. But really! :-)
Forgot to mention that it weights a ton with the base. Literally 2,800lbs. Still want it? :)

In fact you can find similar gantry on ebay for 1/50 of the original price. Here's a smaller one from the same guys I got mine from: http://cgi.ebay.com/140380780081 the drive electronics is mostly useless and needs to be retrofitted with something newer.

And another one that is less pristine and does not have the anocast base or stand with it: http://cgi.ebay.com/260613455523

The Renishaw linear encoder head is around $500-$1000 in single quantities and the scale is $3-5/cm - not cheap at all.

bootstrap
 
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Re: RE: Business models for having a PnP

Post by bootstrap »

scsi wrote:
bootstrap wrote: Anyway, please leave your gantry, linear motors and encoders to me in your will... just in case something terrible happens! Hahahahaha. But really! :-)
Forgot to mention that it weights a ton with the base. Literally 2,800lbs. Still want it? :)]/quote]
You bet I do!

In fact you can find similar gantry on ebay for 1/50 of the original price. Here's a smaller one from the same guys I got mine from: http://cgi.ebay.com/140380780081 the drive electronics is mostly useless and needs to be retrofitted with something newer.

And another one that is less pristine and does not have the anocast base or stand with it: http://cgi.ebay.com/260613455523

The Renishaw linear encoder head is around $500-$1000 in single quantities and the scale is $3-5/cm - not cheap at all.
I don't expect building something as radically cool as this to be free, or even "cheap". Years ago I built automated telescopes that cost tens of thousands just for parts and materials. OTOH, I still believe it is possible to make a very small and fairly slow pick-and-place machine for a fraction of what they cost now.

20 years ago I bought a $150 Houston Instruments ink-pen plotter that drew on 12" x 18" flat paper (on a flat platten), and it was accurate to better than 0.001" and even had a head that goes up and down (to raise and lower the ink-pen). While a pick-and-place needs to have more elements than that, and should be somewhat sturdier, the fact remains that a "designed from scratch" pick-and-place machine for smallish PCBs could be quite inexpensive. Another mental image is ink-jet printers, which also contain some cheap but precise technology that is similar to what a cheap PaP would need. As far as I can see, nobody is really trying to "revolutionize the market".

On the personal level, though, I ***much*** prefer a 3000 pound super-precise beast! Not kidding! So go ahead and make out that will... just in case! I promise to do wonderful things with it if something terrible happens. In fact, I have a few very special-purpose applications for your device already conceived. For example, for some high-speed, high-precision object-chasing telescopes I'm designing, I sure would love to have gigantic optical encoders directly on the rotation axes (which are large flat metal plates). What I'd love to do is laser-cut a huge number of slots in the periphery of thin discs of stainless-steel (? or nickel ?) to make part of the rotating axes. That's something your system would be fabulous for. I invented an alternate way to make these discs that's also very precise, but requires me to build a very non-trivial device/machine to do so - whereas your system is already perfecto. Anyway, it won't go to waste if you give it to me - you can be sure of that!

What X,Y,Z range does your system have? I imagined it to be somewhat larger than the first link took me to (I saw that first listing before, but didn't realize how precise was its gantry).

scsi
 
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Re: RE: Business models for having a PnP

Post by scsi »

bootstrap wrote:What X,Y,Z range does your system have? I imagined it to be somewhat larger than the first link took me to (I saw that first listing before, but didn't realize how precise was its gantry).
If I remember correctly, it's 500mmx650mm in XY and about 150mm in Z axis. I use it for precision milling most of the time. Here's a quick video with it machining some light plastic for PnP feeders (right after the nozzle changer testing): http://www.youtube.com/watch?v=bYfD0UUKyek

By the way, there is a PnP building thread on CNCZone: http://www.cnczone.com/forums/showthread.php?p=720240
Many folks are thinking about building a small PnP and some are trying, but I haven't seen anything compelling yet...

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ktownsend
 
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Re: Business models for having a PnP

Post by ktownsend »

bootstrap wrote:Also tell me anything you can about the relative advantages and disadvantages of trying to get production in asia versus a western country (of the modest quantities that we need). My back of the envelope calculation implies $3 to $6 each for my larger PCB if done with my own pick-and-place machine (not counting ?my? labor to keep an ear on the machine, assuming we can "hear" sounds or interruptions when human attention is required).
I think rather than spending the time writing a long response here, I'm going to put together an article on the decisions behind the PnP versous outsourcing. I'll post a link here in a couple days when it's done. BUT ... in my opinion, for small quantities it's better to pay a bit more and go local since it's easier to monitor, and at least with a European company I'm 99% certain that things are really ROHS compliant and I'm not getting repalcement parts. Just one plane ticket to Hong Kong plus the Chinese visa and BANNED adds up (1500€ or so). There are a number of central European assembly houses that offer fair prices that probably end up cheaper in the long run and are only a couple hours away by plane or even car if you're on the continent.

I think it's an interesting topic to write about, though, and I'll post a link once I have a blog post about it comparing some pros and cons for small scale manufacturing (in house vs. outsourcing).

Kevin.
Last edited by ktownsend on Tue Jun 15, 2010 5:49 pm, edited 1 time in total.

mikeselectricstuff
 
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Re: Business models for having a PnP

Post by mikeselectricstuff »

Also tell me anything you can about the relative advantages and disadvantages of trying to get production in asia versus a western country (of the modest quantities that we need).
For jobs with minimal manual work, I'm told that cost difference going Far-East isn't really all that much, once shipping, quality control etc. is taken into account.

charliex
 
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Re: Business models for having a PnP

Post by charliex »

steve ciciora built a slow, relatively cheap machine, one paste, one PnP
http://ciciora.com/index.html

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