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Messages - sghughes42

General discussion / Forum messages
I don't know if this is a known 'feature', but when I log in to the forum, the 'My Messages' icon at the top shows 1 message. I click on this and the messages drop-down shows 'Inbox [1]'. However when I click on this it says 'no messages'.

Any ideas?
DirtyPCBs support / Any disruption?
What sort of disruption are the current challenges in China causing with PCB production and shipping? Are orders being processed at all and what sort of delays might we experience? Also, is shipping impacted at all - I know many passenger flights are being cancelled, is freight getting through?

I hope all is well with the DPCB team!
DirtyPCBs support / Practical limits?
I'm hoping to start a discussion to find out what others have used in terms of design limits and what success they have had with the resulting boards.

For example, the minimum track / gap is quoted as 6 mil. I tend to be conservative here and use 10 mil unless I have a really tight layout where I have gone down to 8 mil. Does anyone regularly use 6 mil and if so, what sort of success rate have you had? FWIW, I've had no issues at all with 8 mil.

However, for vias I have had some issues. They quote 12 mil as the smallest finished size and 2 mil as the drill position tolerance. I've used vias which I defined as 28 outer, 14 mil hole where some boards are scrap due to issues with these vias. I even had one where I used 32/16 and a few vias were faulty. These were 0.8mm thick boards. I would say that only a small percentage of boards were faulty this way

Conversely, I've had 20/12 vias which worked fine so maybe it's a board house issue.

Anyone else care to share their experiences? It'd be good to get a feel for what the service can actually deliver reliably so we can either push closer to the limits or back off a bit to ensure we get working PCBs.
General discussion / Re: New $14 MPLAB Snap In-Circuit Debugger/Programmer
Sounds interesting, one question though, I may be looking in the wrong place, but where do you download this from?

Or do you have to make a donation to get the code? Reason I ask is that I'm having problems with my PICKit3 on my new machine, it isn't recognised by Windows or the old scripting app yet somehow MPLAB IPE works with it. If there is some incompatibility that would prevent this working then no point getting it, so I'd like to test before I buy.
General discussion / Re: New $14 MPLAB Snap In-Circuit Debugger/Programmer
Interesting how they tout the PicKit4 as a production programmer now - I thought the PicKit range were all dev only.

Main problem I can see with this is that being a bare PCB it will break much faster. How many of us ground ourselves every time we pick something up, or have a desk clear of metal objects?

All that said, to me the main reason I've not upgraded beyond the PICKit3 is the software. The MPLab IPE is shockingly bad to use. The old PICKit2 interface (upgraded for the PICKit3) is so much easier and faster to use, I really can't understand why they got rid of it in favour of an IPE that takes an age to load and can't automatically ID chips.
DirtyPCBs support / Silk now digitally printed?
Just got my latest batch of boards from DPCB and noticed the silk screens appear to be printed on a dot-matrix. Looks good in general, however very small text doesn't render too well. That's more something for designers to be aware of rather than a criticism of the service though - I know I push component IDs a bit small at times.
DirtyPCBs support / Re: Vias not connected through board
I've had a few boards like this recently on one batch of PCBs. The via in question was a 32 thou pad with a 16 thou hole so not exactly pushing the limits - I've used tighter without issue.

On the boards in question the drill hole looks rather over sized so I wonder if there is some issue there, either they are rounding up too much from thou to mm or maybe someone picked the wrong tool to put in the machine. Out of the batch of PCBs, only a handful so far have the issue, the rest are fine so it could be worth checking your other boards as it may only affect some from the batch.

Generally vias don't plate if there isn't enough copper left after drilling. I can't find a specific specification for the size of the annular ring but in general 5 or 6 thou seems widely used elsewhere. It's also worth checking how your CAD package outputs drill sizes. Most output finished hole size but there might be some setting to assume plating thickness and output an oversized drill.
DirtyPCBs support / Re: Board minimum dimensions
I've done boards exactly the same size with no problem at all. I don't know if you are intending to do just a single board or a larger panel, I do panels with plenty of nibs / mouse bites connecting the boards together and everything I've thrown at them has worked so far. This includes boards which are only a couple of mm wide. (Strips with 0603 LEDs on)
DirtyPCBs support / New Year closures
Guys, is there any information available from the factory and shipping agent to indicate when we need to place orders by to avoid being affected by the Lunar New Year holiday?

DirtyPCBs support / Re: Are you paying DHL on receipt of your PCBs?
I recently tried FedEx to see if they were any better than DHL. Wasn't a great experience...

Firstly, their service seems a lot slower than DHL - they say 2-5 days but it seemed to take forever for anything to happen once they'd picked the parcel up and it was actually 6 working days before delivering.

Worst problem was that they delivered the parcel, then demanded a payment for duty. DHL always tell you the duty due first so if there is anything wrong you can query it before accepting the parcel. Fedex don't give you this option - you've already accepted it (and sort of hoped you've not been charged) then they hit you with a massively inflated bill you've got no way to query.

DHL also have a much better payment system - Fedex don't have any online option, you have to ring up and pay over the phone.

Went back to DHL for my latest order (thanks to Bernadette for sorting this) and the billing was seamless and delivery much quicker. Won't be going Fedex again. Don't mind a slower delivery if the import costs are cheaper but slow delivery and higher charges don't appeal.
DirtyPCBs support / Drill sizes used
The latest batch of boards I had from Dirty PCBs (order 2032821) have come with some really weird drilling. All holes appear to have been drilled the largest they could possibly be while keeping the minimum viable annular ring. Two oval pads have even had slots milled rather than the single, small hole specified in the PCB.

To be honest, this may well make the boards unusable as some holes are a certain size to hold connectors etc in place and I'm not sure there is enough exposed copper left to get a good solder joint to on others.

Is there any reason why the specified drill sizes would be ignored and how can I stop this happening in future?
DirtyPCBs support / Couple of shipping queries
A recent order of ours was shipped on Monday via DHL China but we still haven't had a tracking number. Is this normal?

Also, how is shipping weight calculated on here? A recent order which showed as 2.4kg when ordering came in at under 1kg when shipped. I know someone was having problems ordering PCBs as the weight was coming up over 10kg but if the weight calculation is this far out that might be part of their problem.