Puma board for FreeEMS

Marcos' unmaintained, but still in-use, Puma for FreeEMS circuit board/hardware design!
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Fred
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Re: FreeEMS for Argentina

Post by Fred »

nitrousnrg wrote:I'm this close to stalking you to the death until you setup your servers. jharvey is most valuable doc-wise, and I don't like to bug you for little changes in the documentation.
/me is scared!
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nitrousnrg
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Re: Puma board for FreeEMS

Post by nitrousnrg »

ok *ing, *ing!

btw, the BOM only lacks power transistors/mosfets, and connectors. If the guys from ourpcb do a good job, I'm sending them the BOM to ask for an assembly quote. They use digikey and mouser, so we're fine. I've been wondering for a while how much it cost.
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Re: Puma board for FreeEMS

Post by Fred »

Exactamente, mente, mente! :-) eye for an eye, tooth for a tooth.

Beware of Chinese assembly! When I was there we had some boards made and they came back populated, but resistors were wrong and diodes were backwards and one square chip with the pins underneath was rotated 90 degrees and so on and so forth. Maybe these guys are better, but if it's hand done by some 1usd / year worker, don't count on it. Ask what sort of guarantees they will provide with assembled units re what is their fault and what is yours.
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nitrousnrg
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Re: Puma board for FreeEMS

Post by nitrousnrg »

bah, argentinians sometimes do the same, and we've good and expensive hand labor :p

Usually, the problems come from the unstandardized components position file. That file is used by the pick&place machine (no hands!). The other source of problems is the guy who fills the P&P with the components. A reel put backwards can be catastrophic.

These guys provide "Military standard assembling", and they assemble 1 (one) board so you can check it. If it is ok, they start the production.

Step by step, first we need to see how good the PCBs are.
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Re: FreeEMS for Argentina

Post by jharvey »

nitrousnrg wrote:jharvey is most valuable doc-wise,
I disagree, seems that punk only documents the things I already know ;)

I know my humor is bad, but I had to do it. While I'm at it, how's next year? You folks are currently in next year while that hasn't quite come around to me. Did we get flying cars yet?
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Re: FreeEMS for Argentina

Post by Fred »

jharvey wrote:
nitrousnrg wrote:jharvey is most valuable doc-wise,
I disagree, seems that punk only documents the things I already know ;)

I know my humor is bad, but I had to do it.
Fcuk off! I laughed, loudly, and eveyrone stared at me.
While I'm at it, how's next year? You folks are currently in next year while that hasn't quite come around to me. Did we get flying cars yet?
OK, that wasm't funy.

Fred/
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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Re: Puma board for FreeEMS

Post by EssEss »

nitrousnrg wrote: ... Step by step, first we need to see how good the PCBs are.
fred's chinese experience is the same as mine. when they get new customers (which typically end up as one-off customers) it's cheaper to have someone do them by hand and thats where all the assembly errors are made. once they have you hooked, they'll move to pick-n-place and errors drop dramatically. you now have to worry about counterfeit parts at that point :) if the machine is loaded wrong, they typically eat the rework costs, but to ship back still costs time and money and so rework usually gets done locally (in country or in house) on the company's dollar anyways.

another issue I run into is 'stalling' - they'll tell you that they can turn the assembled board around in 1wk, but about mid-week they'll start stalling you about part numbers (and anything else which has already been spec'd in the original quote) to buy more time and it ends up taking as long as all your other quotes. this tactic works good for US customers since we're on the other side of the world and 1 question == 1 day.

in my experience, china is good for quantities in the thousands+ ... but for proto's local manufacturers have always turned out to be cheaper long term and honest in their quotes.
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nitrousnrg
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Re: Puma board for FreeEMS

Post by nitrousnrg »

EssEss wrote:
nitrousnrg wrote: ... Step by step, first we need to see how good the PCBs are.
fred's chinese experience is the same as mine. when they get new customers (which typically end up as one-off customers) it's cheaper to have someone do them by hand and thats where all the assembly errors are made. once they have you hooked, they'll move to pick-n-place and errors drop dramatically. you now have to worry about counterfeit parts at that point :) if the machine is loaded wrong, they typically eat the rework costs, but to ship back still costs time and money and so rework usually gets done locally (in country or in house) on the company's dollar anyways.

another issue I run into is 'stalling' - they'll tell you that they can turn the assembled board around in 1wk, but about mid-week they'll start stalling you about part numbers (and anything else which has already been spec'd in the original quote) to buy more time and it ends up taking as long as all your other quotes. this tactic works good for US customers since we're on the other side of the world and 1 question == 1 day.

in my experience, china is good for quantities in the thousands+ ... but for proto's local manufacturers have always turned out to be cheaper long term and honest in their quotes.
So constructive input! Most appreciated essess, I don't have experience with chinese MFGs, so this kind of stuff weights a lot in my head.

About stalling... qué hijos de put*! (this one is for Fred;-)
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Re: Puma board for FreeEMS

Post by jharvey »

nitrousnrg wrote:I don't have experience with chinese MFGs, so this kind of stuff weights a lot in my head.
Also note that Hong Kong has a different legal structure which correlates to a slightly different experiences. However the end result is about the same, if you have less than 100 boards, it's not worth the export problems. If you have the 1000+ boards there's potential for cost reduction, however quality issues can easily eat up the cost benefits. Typically you'll need to build a china test jig, which can be as complicated or more complicated than the board being mfg'ed. The test jig allows china to verify if it comes close to functional or not. Then when it gets to you, you have to run it on the same jig, and then do a separate more through inspection / stress test. It's a lot of work and has a lot of room for error.

I understand the legal structure differences have something to do with Hong Kong following or once having some kind British influence. So that area followed rules set by the British. Something like that.
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Re: Puma board for FreeEMS

Post by Fred »

Hong Kong was British, and when they gave it back to China they said "But you have to keep our rules!" and it is completely different, despite the proximity and ownership. Still, one of the differences is in price, HK is an expensive place, unlike just over the border.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
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FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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