jim:
? You can import Gerbers files into the pcb editor.

Dave - WB6DHW

On 12/17/2022 2:28 AM, Jim Pruitt via groups.io wrote:

Can anyone tell me how to correctly merge 2 GBR files into one file?? I have a project from a web site.? The designer sent me the gerbers but the project lacks a top solder mask.? Also when the designer made the original boards 15 years ago he split the top layer into 2 separate files.? Since the top layer is MOSTLY ground plane (but not completely) I could not figure out why he has a ground.gbr which is the top layer ground plane but also has a compside.gbr for the 3 or 4 runs that do not tie to that top ground plane.? He used a pcb program from that time but I had never heard of it.? As you might guess,? no board house I found would even touch that.? JLCPCB finally told me to go back and put that top layer into one file and then resubmit it.? I have Kicad 6.? The designer did not share his project file or any schematic file.? The gerbers consisted of the bottom layer (solder.gbr) and a solder mask for that bottom layer (mask.gbr) and then the 2 top layer files (compside.gbr and ground.gbr).? I was hoping I could take a text editor (Notepad++) and merge/combine those 2 top layer gerber files but not sure what I am doing or how to do it.? I did some comparison and both files started out with the same 20 or so first items but then some items were different after that.? The board is a 2 layer board for through hole components so no smt parts involved.

Also how can I make the top layer solder mask be created since none was included?? Or is it even possible without having the schematic file and a complete project?

Any help would be greatly appreciated.

Thank you.

Jim Pruitt

Can anyone tell me how to correctly merge 2 GBR files into one file?? I have a project from a web site.? The designer sent me the gerbers but the project lacks a top solder mask.? Also when the designer made the original boards 15 years ago he split the top layer into 2 separate files.? Since the top layer is MOSTLY ground plane (but not completely) I could not figure out why he has a ground.gbr which is the top layer ground plane but also has a compside.gbr for the 3 or 4 runs that do not tie to that top ground plane.? He used a pcb program from that time but I had never heard of it.? As you might guess,? no board house I found would even touch that.? JLCPCB finally told me to go back and put that top layer into one file and then resubmit it.? I have Kicad 6.? The designer did not share his project file or any schematic file.? The gerbers consisted of the bottom layer (solder.gbr) and a solder mask for that bottom layer (mask.gbr) and then the 2 top layer files (compside.gbr and ground.gbr).? I was hoping I could take a text editor (Notepad++) and merge/combine those 2 top layer gerber files but not sure what I am doing or how to do it.? I did some comparison and both files started out with the same 20 or so first items but then some items were different after that.? The board is a 2 layer board for through hole components so no smt parts involved.
Also how can I make the top layer solder mask be created since none was included?? Or is it even possible without having the schematic file and a complete project?
Any help would be greatly appreciated.
Thank you.
Jim Pruitt

On Sat, Dec 17, 2022 at 04:28 AM, Jim Pruitt wrote:

Can anyone tell me how to correctly merge 2 GBR files into one file?? I have a project from a web site.? The designer sent me the gerbers but the project lacks a top solder mask.? Also when the designer made the original boards 15 years ago he split the top layer into 2 separate files.? Since the top layer is MOSTLY ground plane (but not completely) I could not figure out why he has a ground.gbr which is the top layer ground plane but also has a compside.gbr for the 3 or 4 runs that do not tie to that top ground plane.? He used a pcb program from that time but I had never heard of it.? As you might guess,? no board house I found would even touch that.? JLCPCB finally told me to go back and put that top layer into one file and then resubmit it.? I have Kicad 6.? The designer did not share his project file or any schematic file.? The gerbers consisted of the bottom layer (solder.gbr) and a solder mask for that bottom layer (mask.gbr) and then the 2 top layer files (compside.gbr and ground.gbr).? I was hoping I could take a text editor (Notepad++) and merge/combine those 2 top layer gerber files but not sure what I am doing or how to do it.? I did some comparison and both files started out with the same 20 or so first items but then some items were different after that.? The board is a 2 layer board for through hole components so no smt parts involved.

Also how can I make the top layer solder mask be created since none was included?? Or is it even possible without having the schematic file and a complete project?

Any help would be greatly appreciated.

Thank you.
Jim Pruitt

Jim,
If the board isn't too large and complicated, I'd consider just using Kicad to redraw the board and create new Gerbers from that.? I've done that on a couple of old magazine projects in which the project files weren't availabe.? You don't need a schematic to just draw a board from scratch.??
I don't know if Kicad allows you to place an image on the board space, but if it does, I'd suggest that you use a Gerber viewer (I use Gerbv) to create an image file (Gerbv can export files to .PNG, .PDF, .SVG, etc.), then draw the traces and pads over the image.? Then, you'd have everything you need for the fab house to build a good board.
Of course, a complicated board makes the task quite tedious, but this might be the best solution in the end.

My $0.02 worth,
DaveM

?

I have several questions about smt solder mask templates.? A while back I ordered some bare pc boards from/for the Adafruit Si5351 pll modules. The board is small as about an inch by 3/4" or so. When I ordered the boards from JLCPCB I also ordered a stencil (unframed). When they arrived the stencil was on a piece of stainless steel about 11x17 inches.? Did I mention that the board it was for is only an inch by 3/4 inch?? I wondered if I had ordered the framed stencil if it would have been board size.? A few nights ago I was doing some internet searching and ran across an Adafruit series on stencils:





One of those articles recommended this stencil frame which is a glorified screen printing style frame:


Unfortunately that frame is $1000 so that is way out of my hobby budget!? Does anyone know of a much cheaper stencil frame than the Madell tech one?

The next questions deal with how to cut the stencil.? I want to be able to lay the stencil on the board so that the stencil is exactly the size of the pc board and registers correctly.? I do not know how to do that.? If I lay the stencil on the pc board then I can not cut the stainless steel without moving it which looses registration.? So the question is how do I trim the stencil to board size and keep it so it registers correctly?? I asked JLCPCB that question but they did not understand the question and told me to put registration guides in the gerbers (that would not help).

I had also bought a stencil from ProtoAdvantage for the TSSOP10 Si5351 chip but that was a big mistake.? The TSSOP10 footprint is a very thin 2x5 footprint and it was almost impossible to get it registered over the pc lans to apply solder paste because there was nothing else to reference against (in/on the frame) and with the very tiny slits I never was able to get it aligned on the board and apply paste.? I ended up just hand soldering the IC but there has to be a better way to do it.

Do you have any suggestions?

Thank you.

Jim Pruitt

On Jul 31, 2022, at 8:59 AM, Kevin Byrne via groups.io <kbyrne10@...> wrote:

?

Try a search of USA companies like Office Depot. They are who I use.

On Sunday, July 31, 2022 at 08:27:29 AM EDT, russell shaw <rjshaw@...> wrote:

On 31/7/22 21:44, Mike wrote:
> I used to buy JetStar transparent sheets for inkjet printers from Mega UK.
> However Mega is now out of business. Those transparent sheets did have a
> "sticky" layer on one side. Has anyone found a source of equivalent sheets? I
> recall trying some sheets earlier, but I didnt gett the needed black saturation
> that I got with the Mega UK sheets.

Maybe CG3420

3M CG3420 TRANSPARENCY FILM

<multimedia.3m.com/mws/media/360213O/cg3420.pdf>

Other searches turn up 'coated' film, which should be gelatine iirc.

<>

Avoid ones that work with laser printers because they're likely the 'sandpaper'
ones.

?

Please excuse my ignorance. Can someone tell me what a framed solder mask stencil is?? My suspicion is that it is a stencil that fits into some kind of contact frame like screen printing but I have not found an explanation that makes sense to me.? If I am correct then where does one find these contact frames and what are they called?

I asked because I was looking to order some smt boards from one of the Chinese board houses and for $7 I can get a frameless stencil but for $9.20 or so I can get one for a frame.? To me it would be ideal to have a frame since registration would be easier.

Also I have not figured out why all the board houses send a 380mm x 280mm even if the board it is for is small like 32mm x 22mm and that confuses me. Why isn't the stencil a few mm larger than the pc board but not gargantuan like it is?

Again what are the solder mask stencil frames called and where can I get one?? What is a stencil for frames compared to frameless?? Why are the board house stencils so huge compared to the actual size of the pc board the stencil is for?

Thank you.

Jim Pruitt