Another PCB Fab Thread

On 4/18/2016 3:15 AM, John Devereux wrote:
> rickman <gnuarm@gmail.com> writes:
>
>> On 4/17/2016 8:28 PM, Paul Rubin wrote:
>>> rickman <gnuarm@gmail.com> writes:
>>>> I know there are a couple of Chinese fabs with good prices and decent
>>>> quality, but I don't recall who they are.
>>>
>>> I bookmarked this a while back:  http://dirtypcbs.com/index.php
>>>
>>> I just came across it while looking for something else.
>>
>> Wow!  10 each, 10x10 cm, 4 layer boards for $50 in 8 days plus
>> shipping if you aren't happy with the sometimes very slow Hong Kong
>> post.  That is amazingly cheap.
>
> There are a few others with similar pricing, e.g. Elecrow. I have used
> both with good results. DirtyPCB will also do larger boards if
> asked. Not for quite such ridiculously low prices but still very good.
>
> Also see <http://pcbshopper.com/> if you have not already.

I looked at the Elecrow web site and it basically didn't work.  The page 
for 4 layer boards only had 1 and 2 layers as options and other problems.

PCBshopper is interesting.

-- 

Rick

rickman <gnuarm@gmail.com> wrote:
> On 4/17/2016 8:28 PM, Paul Rubin wrote:
> > rickman <gnuarm@gmail.com> writes:
> >> I know there are a couple of Chinese fabs with good prices and decent
> >> quality, but I don't recall who they are.
> >
> > I bookmarked this a while back:  http://dirtypcbs.com/index.php
> >
> > I just came across it while looking for something else.
> 
> Wow!  10 each, 10x10 cm, 4 layer boards for $50 in 8 days plus shipping 
> if you aren't happy with the sometimes very slow Hong Kong post.  That 
> is amazingly cheap.

We've just had some back from there - simple 2 layer, HASL, for 10 pounds
including shipping.  Quality looked nice.  (HASL gives a slight
non-planarity in the solder dip, but that's fine for many applications)

Theo

Seeed Studio also has some cheap pcb fab:

http://www.seeedstudio.com/depot/Services-c-70_71/

On 4/20/2016 11:48 PM, Paul Rubin wrote:
> Seeed Studio also has some cheap pcb fab:
>
> http://www.seeedstudio.com/depot/Services-c-70_71/

Yes, their prices are not bad, didn't check the specs.  I was looking at 
pricing options and they said it was +$30 to panelize 4 boards, but they 
added $60 to the order.  I guess they double the charge for 4 layer 
boards.  What's with that anyway?  How do they have a higher cost for 
panelized boards?

-- 

Rick

On 4/21/2016 1:16 AM, rickman wrote:
> On 4/20/2016 11:48 PM, Paul Rubin wrote:
>> Seeed Studio also has some cheap pcb fab:
>>
>> http://www.seeedstudio.com/depot/Services-c-70_71/
>
> Yes, their prices are not bad, didn't check the specs.  I was looking at
> pricing options and they said it was +$30 to panelize 4 boards, but they
> added $60 to the order.  I guess they double the charge for 4 layer
> boards.  What's with that anyway?  How do they have a higher cost for
> panelized boards?

I checked the specs and they get pretty sloppy for 4 layer boards.  Not 
sure why the inner layers have worse trace/space than outer, but it's 
8/10 mils.  That's pretty poor.

-- 

Rick

rickman wrote:

> On 4/21/2016 1:16 AM, rickman wrote:
>> On 4/20/2016 11:48 PM, Paul Rubin wrote:
>>> Seeed Studio also has some cheap pcb fab:
>>>
>>> http://www.seeedstudio.com/depot/Services-c-70_71/
>>
>> Yes, their prices are not bad, didn't check the specs.  I was looking at
>> pricing options and they said it was +$30 to panelize 4 boards, but they
>> added $60 to the order.  I guess they double the charge for 4 layer
>> boards.  What's with that anyway?  How do they have a higher cost for
>> panelized boards?
> 
> I checked the specs and they get pretty sloppy for 4 layer boards.  Not
> sure why the inner layers have worse trace/space than outer, but it's
> 8/10 mils.  That's pretty poor.

That is for 2oz copper. For the usual 1oz Cu it's 6 mil outer and 8 mil 
inner layer.
<http://support.seeedstudio.com/knowledgebase/articles/447362-fusion-pcb-
specification> 
Surcharge for panelized boards applies only if the boards are different. The 
higher price is probably for the additional processing step for V-cuts.

-- 
Reinhardt (not affiliated with Seeed, just a satisfied customer)

On 4/21/2016 2:06 AM, Reinhardt Behm wrote:
> rickman wrote:
>
>> On 4/21/2016 1:16 AM, rickman wrote:
>>> On 4/20/2016 11:48 PM, Paul Rubin wrote:
>>>> Seeed Studio also has some cheap pcb fab:
>>>>
>>>> http://www.seeedstudio.com/depot/Services-c-70_71/
>>>
>>> Yes, their prices are not bad, didn't check the specs.  I was looking at
>>> pricing options and they said it was +$30 to panelize 4 boards, but they
>>> added $60 to the order.  I guess they double the charge for 4 layer
>>> boards.  What's with that anyway?  How do they have a higher cost for
>>> panelized boards?
>>
>> I checked the specs and they get pretty sloppy for 4 layer boards.  Not
>> sure why the inner layers have worse trace/space than outer, but it's
>> 8/10 mils.  That's pretty poor.
>
> That is for 2oz copper. For the usual 1oz Cu it's 6 mil outer and 8 mil
> inner layer.
> <http://support.seeedstudio.com/knowledgebase/articles/447362-fusion-pcb-
> specification>
> Surcharge for panelized boards applies only if the boards are different. The
> higher price is probably for the additional processing step for V-cuts.

You misunderstand what I wrote.  Inner layer is 8 mil trace, 10 mil 
space regardless of copper thickness.  They list copper thickness of the 
outer layer as 1 or 2 oz and don't distinguish between these for the 
trace resolution.  The inner layers are always 0.5 oz., so the inner 
layer trace width would not vary based on outer layer thickness.

They also mix units between mm and mils as the selected unit for the 
spec.  Example, Minimum inner trace width (for 4 layer) 0.204 mm, 8 mil. 
  Drilling Hole Diameter (Mechanical) 0.3 mm, 11.81 mil.  It would be 
nice if they used the same unit type as the primary units for all the 
specs.

-- 

Rick

joi, 21 aprilie 2016, 09:47:08 UTC+3, rickman a scris:
> On 4/21/2016 2:06 AM, Reinhardt Behm wrote:
> > rickman wrote:
> >
> >> On 4/21/2016 1:16 AM, rickman wrote:
> >>> On 4/20/2016 11:48 PM, Paul Rubin wrote:
> >>>> Seeed Studio also has some cheap pcb fab:
> >>>>
> >>>> http://www.seeedstudio.com/depot/Services-c-70_71/
> >>>
> >>> Yes, their prices are not bad, didn't check the specs.  I was looking at
> >>> pricing options and they said it was +$30 to panelize 4 boards, but they
> >>> added $60 to the order.  I guess they double the charge for 4 layer
> >>> boards.  What's with that anyway?  How do they have a higher cost for
> >>> panelized boards?
> >>
> >> I checked the specs and they get pretty sloppy for 4 layer boards.  Not
> >> sure why the inner layers have worse trace/space than outer, but it's
> >> 8/10 mils.  That's pretty poor.
> >
> > That is for 2oz copper. For the usual 1oz Cu it's 6 mil outer and 8 mil
> > inner layer.
> > <http://support.seeedstudio.com/knowledgebase/articles/447362-fusion-pcb-
> > specification>
> > Surcharge for panelized boards applies only if the boards are different. The
> > higher price is probably for the additional processing step for V-cuts.
> 
> You misunderstand what I wrote.  Inner layer is 8 mil trace, 10 mil 
> space regardless of copper thickness.  They list copper thickness of the 
> outer layer as 1 or 2 oz and don't distinguish between these for the 
> trace resolution.  The inner layers are always 0.5 oz., so the inner 
> layer trace width would not vary based on outer layer thickness.
> 
> They also mix units between mm and mils as the selected unit for the 
> spec.  Example, Minimum inner trace width (for 4 layer) 0.204 mm, 8 mil. 
>   Drilling Hole Diameter (Mechanical) 0.3 mm, 11.81 mil.  It would be 
> nice if they used the same unit type as the primary units for all the 
> specs.
> 
> -- 
> 
> Rick

Specs in mm are annoying. Does anybody work in mm for pcb designing?

On 21/04/16 11:01, raimond.dragomir@gmail.com wrote:

> 
> Specs in mm are annoying. Does anybody work in mm for pcb designing?
> 

Yes, most of the world does.

Apart from Americans, I think it is just older Brits that use metric
units for any sort of specifications.  It is not uncommon to use mils
for approximate numbers for track width and spacing, simply because you
get nice numbers like 8 mil rather than 0.2 mm.  But when you need
accurate numbers, metric is how almost everyone outside the USA does it.

joi, 21 aprilie 2016, 12:08:14 UTC+3, David Brown a scris:
> On 21/04/16 11:01, raimond.dragomir@gmail.com wrote:
> 
> > 
> > Specs in mm are annoying. Does anybody work in mm for pcb designing?
> > 
> 
> Yes, most of the world does.
> 
> Apart from Americans, I think it is just older Brits that use metric
> units for any sort of specifications.  It is not uncommon to use mils
> for approximate numbers for track width and spacing, simply because you
> get nice numbers like 8 mil rather than 0.2 mm.  But when you need
> accurate numbers, metric is how almost everyone outside the USA does it.

Wow, I thought everybody works in mils for pcb designing...
I'm not american, but I work in mils for pcb layout
since I started my career in embedded systems, 20 years ago...