RIDICULOUSLY CHEAP PCB's!!

[6666]

[Mdtoday]

Ok, one not to give up, I did the board again, this time using circular segments for the tracks....really, it should not be the problem but I'm going to find out what it is they don't like about the shape.
Contacted them 3 times and each time it was a different issue..last time they said it was lack of silkscreen!? It was not selected because I didn't want one lol.

Over at PCBway, they happily take your order..charge you twice as much as JLpcb...but you get what you ask for.

Mind you, JLPCB have done a great job with my last 8 orders, this one is strange...

[kt315]

anyone has to do a gerber. just then aperturas would to be sure understandable.
how about JLCPCB are a huge company we know it. every chinese seller is always huge company.
especcially in Shēnzh?n.

[Mdtoday]

Further to the JLPCB PCB coil order.
I removed circular vslots around circumference and added a silkscreen and increased board thickness from 1.2mm to 1.6mm ... they were happy to manufacture this, in fact they are completed and on the way.
Original design with complete circular cut-outs was accepted over at PCBway with roughly a 30% cost increase.

[6666]

Further to the JLPCB PCB coil order.
I removed circular vslots around circumference and added a silkscreen and increased board thickness from 1.2mm to 1.6mm ... [ATTACH]47243[/ATTACH] they were happy to manufacture this, in fact they are completed and on the way.
Original design with complete circular cut-outs was accepted over at PCBway with roughly a 30% cost increase.

Interesting, what inductance value are the pcb's ? do you have any spare ?

[Mdtoday]

Interesting, what inductance value are the pcb's ? do you have any spare ?

Hi 6666, Inductance is 155uH per side from past experience this will yield approx 298 - 305uH.
I only ordered 5 units this time as I wanted to check JLPCB out for these designs, I will be ordering again in a week or so if they are good quality.
Will let you know later this week after I check the values, R, I, SFR and Q, I might be able to send you one.
The next batch will be larger >290mm and slightly different design.

Cheers

Mdtoday

[Carl-NC]

I removed circular vslots around circumference...

So it's not the circular traces, but the circular routing that's the problem? Even with a language barrier they could have explained that to me.

Here is what I submitted:



I suppose I could put a small hole in the center and then use my Dremel with a circle-cutting jig to route out all the coils.

[green]

Hi 6666, Inductance is 155uH per side from past experience this will yield approx 298 - 305uH.
I only ordered 5 units this time as I wanted to check JLPCB out for these designs, I will be ordering again in a week or so if they are good quality.
Will let you know later this week after I check the values, R, I, SFR and Q, I might be able to send you one.
The next batch will be larger >290mm and slightly different design.

Cheers

Mdtoday

Do you expect the inductances to add? https://www.geotech1.com/forums/show...000#post260000 F117 got 3 times the inductance, maybe not the same?

[6666]

Hi 6666, Inductance is 155uH per side from past experience this will yield approx 298 - 305uH.
I only ordered 5 units this time as I wanted to check JLPCB out for these designs, I will be ordering again in a week or so if they are good quality.
Will let you know later this week after I check the values, R, I, SFR and Q, I might be able to send you one.
The next batch will be larger >290mm and slightly different design.

Cheers

Mdtoday

Thanks

[Mdtoday]

Do you expect the inductances to add? https://www.geotech1.com/forums/show...000#post260000 F117 got 3 times the inductance, maybe not the same?

Hi Green, that is correct, generally about 3 times larger, on these test units I have tap points on one layer and pick off from 4 points 290 - 450uH.
I have found quite a difference in inductance on these boards, to date, at least a 10% variation between manufacturers for the same design and over the last year or so, I have tried 5 different board houses both local and in China.
JLPCB will be the 6th. Variation between batches from each manufacturer <3% (2 batches from each)

[Mdtoday]

So it's not the circular traces, but the circular routing that's the problem? Even with a language barrier they could have explained that to me.

Here is what I submitted:

[ATTACH]47276[/ATTACH]


I suppose I could put a small hole in the center and then use my Dremel with a circle-cutting jig to route out all the coils.

Nice design.

To be honest, I am not sure what their problem is, I have tried different variations and submitted.
It seems to be related to physical production handling of a larger round board (panel) which is weird as I have had 50mm round sensor boards produced by them with circular v slots...
I am only persisting with them on a cost basis, meanwhile, over at PCBway I have a 460 mm CC design being produced on .8 mm board not a problem.

[dbanner]

edited

[waltr]

It is possible that it is the 'square' inside ends of the curved slots that flagged Carl's coil board as not doable.

Wonder if it will be accepted if those slot ends have a radius.

[Carl-NC]

It is possible that it is the 'square' inside ends of the curved slots that flagged Carl's coil board as not doable.

Wonder if it will be accepted if those slot ends have a radius.

I've generally found that square inside corners are not a problem, it's understood they will get rounded.

I removed the slots, made the overall PCB square, and added 1/8" drill holes for setting up my Dremel circle cutter. JLC accepted it and, in fact, made the boards in 1 day and they shipped today. Unfortunately, when I placed the order I forgot to specify 2oz copper so my series R will be high. Oh well, I can still do some comparison tests.

[Mdtoday]

Received the test pcb coils this morning, they look ok.
I can put them on the CNC and cut the outer, not a problem but I'd prefer to have them done.




I'll take some measurements later but they are as ordered.
If they are Ok, I will keep the design on a square panel, add the circular Vslots and submit at various widths, add another board layout into the centre and let them do the panel etc.
Basically try different things. I have talked with them but they prefer the email trail which suits me too.