LB SMT service

Community PCB Design
1

EDIT: I changed the name of the thread. Since this is an absolute now…and not a possibility.
If your interested, watch for threads with LB SMT in the title. /EDIT

I’m a new business owner (actually started it myself last year).

I’m looking to possibly offer surface part placement.

I’m wondering who would be interested.

I’m not sure of the rates…but the way I’m looking at doing it is as follows:

There will be a setup fee for a new board design. (thinking about 10-15 bucks)

Placement fees will be according to pads. (certain price for each pad)

If the design changes (minor change…moved part, added part, removed part) there will be a small design change fee (this is based on previous orders)

I’m looking at people that will have small volume runs. 5-100 boards per run.

The problem…it would be impossible to totally test the assembled board. Also…the parts would have to be supplied.

Let me know your ideas and opinions,

James L

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I can imagine using this service, depending on what the “certain price for each pad” turns out to be…

Will customers be required to provide a solder paste stencil?

What’s the finest pitch/smallest package size you’ll deal with? I suspect you may eventually want to have this be a factor in the price - placing a 1206 is not the same thing as placing a 01005…

What sort of guarantee will you offer (for example, if you accidentally place an expensive BGA upside-down, and the customer doesn’t have the equipment to rework it themselves)?

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Jason,

No stencil needed.

I’m looking at 0402 as the smallest. I may go as low as 0201. I know it will not be smaller than 0201.

No…I probably won’t calculate the size in the price. I’m not sure at this point how to do the calculation, but I know the more boards you have done…the cheaper per pad the price will be.

Just because something is smaller is not necessarily the case…they get to only have two pads when they are small. A 44 pin QFP would be more expensive than a 0201 capacitor. The reason…if the capacitor is placed wrong…the rework is not that hard ( less likely to toast an expensive part). If a 44 pin QFP is wrong…possibility of toasting a $10 to $150 part.

I guess I should state this will be done with a automatic pick and place machine…not by hand…so the difference between a 1206 and a 0201 is negligible with respect to the machine. The post inspection is a little more difficult, but the machine will be able to accurately place the smallest size when determined.

That is why the pad calculation is better than the size.

I will rework the board for free. I’ll pay shipping.

But at this point…this the view point I have.

James L

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I could see using your service though cost is clearly going to be a significant factor.

The number of pads is a reasonable way to make pricing easy though I don’t see it as totally fair. placing 3 soic20s is going to be a lot less work for you than placing 30 1206s. I would think you would want to price more by the number of components. I get the rework argument but how much rework from place errors is common? I was under the impression that, with a solder mask, ICs are pretty well self aligning once you get them in the ballpark.

I would guess your set up fee is way low.

What ever you do, make it easy for someone to calculate the cost up front. When I’m shopping for a service, I make my first pass with out talking/emailing to the candidate companies. last thing I want is a bunch of sales types calling me up.

How do other shops price jobs?

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Philba,

I placed the setup low…because I think people will appreciate having more than one design built.

The problem with component number pricing is the solder. The more pins the more solder that is used.

I agree placement rework is low…if the user doesn’t put the part backwards.

I’ll try to make the setup pretty easy.

I’m just asking to see if I’ll even offer the service.

James L

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I’m thinking about the pricing… let me know what you think about this:

for 5 boards (probably be the minimum I will do)

$25 setup (this is one time as long as nothing moves or changes)

$0.15 per pad

Plus shipping.

The price will go down if you have more than 5 boards mounted.

Tell me what you think,

James L

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I’d consider it if you support QFN, but .15$ for pad gets expensive pretty quickly… Adding a 100 pin FPGA in LQFP → 1 place, 15$…

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I always wondered what the logic was behind charging per pad as opposed to charging per component. I never thought of solder paste as that big of a price issue. Is paste really that expensive? And even so, number of pads isn’t a very accurate way to estimate the amount of soldering required. A D2pak with 3 pins probably requires as much as a 48 pin tqfp. Ideally, I suppose you could make some program that could determine the exact total area of the pads from gerber files, but I’m not sure how feasible this is.

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I was curious what other companies charged and hunted around a bit. A Canadian company didn’t have their setup/stencil fees listed but charged:

"$0.0125 per pin for SMD

$0.025 per pin for DIP, PTH components."

But 25$ setup is certainly lower than what they charge.

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chrisjp:
I’d consider it if you support QFN, but .15$ for pad gets expensive pretty quickly… Adding a 100 pin FPGA in LQFP → 1 place, 15$…

Chris for a 5 board run…I think $15 for a 100 pin FPGA is pretty cheap.

Considering what is required to place one accurately. I will be able to place components down to 20 mil pitch. I’m not sure your part will fit into the limits, but you could check.

James L

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mtwieg:
I always wondered what the logic was behind charging per pad as opposed to charging per component. I never thought of solder paste as that big of a price issue. Is paste really that expensive? And even so, number of pads isn’t a very accurate way to estimate the amount of soldering required. A D2pak with 3 pins probably requires as much as a 48 pin tqfp. Ideally, I suppose you could make some program that could determine the exact total area of the pads from gerber files, but I’m not sure how feasible this is.

I think you are confusing the issue. The D2pak is much easier to place accurately than a 48 pin tqfp. Which is more likely to require rework. Also since there is no stencil (the machine will have to dispense paste) which will take longer to dispense? Time is money with any service like this. Machine time is very expensive.

But remember…I’m only talking about a 5 board run as an example.

James L

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chrisjp:
I was curious what other companies charged and hunted around a bit. A Canadian company didn’t have their setup/stencil fees listed but charged:

"$0.0125 per pin for SMD

$0.025 per pin for DIP, PTH components."

But 25$ setup is certainly lower than what they charge.

I think that is a pretty cheap price…but you didn’t list their minimum run. I’m sure they will not do less than about 500 boards per run. Most assembly services have large minimums.

I should also state, I’m not going to do wave soldering. I’m not interested in DIP or through hole component placement. I don’t think anyone really needs this service…and would be hard to price for anyone to use.

I’m only doing SMT…and only smt pads will be counted.

(Not directed at Chris)

The following would be the maximums:

40mm maximum component size

0402 minimum component size

20 mil lead pitch

17" x 13.75" max PCB size (this can be panelized boards)

Not sure of the minimum PCB…

Fudicials are required

I’m enjoying the discussion…maybe worth my time to offer this service if we can come to some type of compromise.

James L

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Yep, the site didn’t list their minimums either so I certainly agree with you.

I’m just not sure doing it per pad is going to work out in the long run… Places like screaming circuits (you can quote 10 boards here) charge per smt, per fine pitch placement, regardless of pin count.

Just as an example, I have a board with roughly 350 pads from 5 devices, and would want between say 10 and 40 boards assembled.

Screaming price: 10 day turn.

10 - 445

15 - 505

20 - 566

40 - 807

Your price:

Per board - 52$ + 25 Setup

10 = 520

15 - 805

… etc.

I assume this is as they are using a stencil and most of the cost is up front. However, I think you’ll be hard pressed to hit the prototyping market with quantity > 5 and roughly 50$ boards per setup and you won’t hit the production market with high per pad pricing. Just my opinion though.

I’d love it if i could send off 10-20 boards with bga/qfn’s and have you slap them on however, I assume x-raying will not be an option.

Just some thoughts, and I hope if you decide to start it that it is a huge success :slight_smile:

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I should add that I did see you mentioned a price cut for > 5 boards, but it would have to be a ~50% price cut at q15 to be competitive. I just don’t see how that would be possible if your fixed costs don’t go down, no stencil. But anyways, enough babble :slight_smile:

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chrisjp:
Yep, the site didn’t list their minimums either so I certainly agree with you.

I’m just not sure doing it per pad is going to work out in the long run… Places like screaming circuits (you can quote 10 boards here) charge per smt, per fine pitch placement, regardless of pin count.

Just as an example, I have a board with roughly 350 pads from 5 devices, and would want between say 10 and 40 boards assembled.

Screaming price: 10 day turn.

10 - 445

15 - 505

20 - 566

40 - 807

Your price:

Per board - 52$ + 25 Setup

10 = 520

15 - 805

… etc.

I assume this is as they are using a stencil and most of the cost is up front. However, I think you’ll be hard pressed to hit the prototyping market with quantity > 5 and roughly 50$ boards per setup and you won’t hit the production market with high per pad pricing. Just my opinion though.

I’d love it if i could send off 10-20 boards with bga/qfn’s and have you slap them on however, I assume x-raying will not be an option.

Just some thoughts, and I hope if you decide to start it that it is a huge success :slight_smile:

I see your point… That wouldn’t be good in your situation.

Hmmm…I agree…the pricing is going to be more complicated.

Let me think about it some…surely I can come up with something that will fit the bill.

I very seriously doubt I will offer x-ray as an option… :slight_smile:

James L

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chrisjp:
I should add that I did see you mentioned a price cut for > 5 boards, but it would have to be a ~50% price cut at q15 to be competitive. I just don’t see how that would be possible if your fixed costs don’t go down, no stencil. But anyways, enough babble :slight_smile:

The fixed cost is not the problem in this situation. The more boards you run at once…the more “productive” time the machine is running.

The more time spent changing placement programs and reels of parts (or cut tapes) the less time the machine is actually being productive.

That is why prices go down with larger number of boards. The fixed cost are not the only consideration.

OK…

Try this:

10 boards

$0.05 per pad or $10 per board which ever is more

$35.00 setup.

50 boards

$0.025 per pad or $5 per board which ever is more

$25.00 setup

I would have to do some figuring to do the scaling between the different values , but the scale would be somewhat linear.

Let me know what you think.

James L

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Hmmmm…no more discussion…I think I would need more takers to provide a service like this. I know there are many lurkers out there, so if you are a lurker at least let it be known the service would be used.

I’m thinking about posting at a few other of my favorite sites…but for the people that surf around…pass it around and let me know.

I’m not looking at a huge amount of people to provide the service for…but it would help fill the slow time for the machine.

I’ll keep the current pricing scheme till someone else expresses a view that it is too expensive.

I think I have most others beat with the (current)price.

James L

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I might not be using your service on short term, but maybe some time in the future.

Please keep us updated here!

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At least from my perspective (I’ve never had a board assembled by someone else before), that seems like a pretty good pricing scheme! A 100-pin device would be $5, which seems pretty good!

I suppose my question is, at these prices, is it profitable for you to do a job that may only be ($10*10 + $35) = $135? Does it take quite a bit of time to setup, or is it all pretty quick and requiring little human attention?

thanks

silic0re

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silic0re:
At least from my perspective (I’ve never had a board assembled by someone else before), that seems like a pretty good pricing scheme! A 100-pin device would be $5, which seems pretty good!

I suppose my question is, at these prices, is it profitable for you to do a job that may only be ($10*10 + $35) = $135? Does it take quite a bit of time to setup, or is it all pretty quick and requiring little human attention?

The human interaction really takes place on the setup. The machine has to be monitored, but for the most part the setup is the cost killer.

The parts must be placed on the machine (on a tray if not on reels). The components will have to be taught (software placement), but if the person is using eagle the placement can come from the software. Then the machine is started…and monitored. The board is visually inspected before going to reflow( don’t want to reflow a board that is wrong).

I’ve done the number crunching…and this is the lowest price I can safely go for board assembly. The first run will really be an even break…but will be profitable if the person has a second run.

I am however going to offer 5 boards as a minimum, but the price per board will go up some.

But it should be noted:

I can not X-ray a board (don’t have the capabilities)

I can not electrically test assembled boards (this would require a large amount of human interaction)

At this point I can not test bare pcb’s. (although I’m working on a system that would)

I have not researched the separation of panelized boards, so what ever format I get them in, the customer will receive the same.

I should also state a panelized board is considered one(1). It doesn’t matter how many the panel will make. This will save a large amount of money for people with low part count.(If they are doing a large run)

But the 5 board/panel minimum still applies.

I may even do specials…like a frequent user program…you get a discount on setup or price per board. But I need to get the service working first.

James L