Date   
Re: PCB Milling Techniques

John J <john6060842@...>
 

Hi Sam,

Thanks for sharing your techniques and utilities with the group!

Regards,
JJ


On Fri, Jan 30, 2015 at 7:17 PM, sdmonaco@... [pcb-gcode] <pcb-gcode@...> wrote:
 


Hi Guys!

I have been having very good results with a new PCB milling approach I have been using so I thought I would share it with the group.  The technique is very simple and is very tolerant of dull and/or inexpensive milling tools and does not require auto leveling.

I use Andrew Abken's low cost 30 degree bits from www.drewtronics.net  The 30 degree bits provide the least amount of trace width variation due to PCB thickness variations.

I setup PCB Gcode for single pass isolation and instead of zeroing the z-axis I initially set it to 1 mil above the center of the PCB.  I then etch the traces using this initial setting.  Once complete, I continue to run the trace isolation file lowering the z-axis 1 mill each time.  The technique will usually produce a good clean board after about 2 to 3 etch runs.

Once fully etched, I then proceed to drill and mill the PCB.  Drilling is done normally however I have written a couple of utilities to help with the PCB milling process.  The first routine is called MPASS which takes the PCB Gcode mill output and generates a multi-pass milling file.  I usually generate a 5 pass file which removes 12.4 mils of 62 mil PCB during each pass.  This helps tremendously with tool ware and I never have to use break away tabs.  Yes I do use double sided carpet tape to hold my PCB in place.

The second utility I wrote is called CSCALE.  This program takes the PCB Gcode mill output file and scales it up (or down).  This allows me to use PCB Gcode to design my PCB enclosures and front panels whthout worrying about the 4x6 PCB dimension limits.

I hope this helps with your PCB milling operations and I have added my two utility routines to the files section of the Group.  They are written to run on a standard Windows PC so please let me know if you have any trouble finding or using them.

Thanks, Happy Milling!

Sam




--
Sent from a MacBook Pro

New file uploaded to pcb-gcode

pcb-gcode@...
 

Hello,


This email message is a notification to let you know that
a file has been uploaded to the Files area of the pcb-gcode
group.


File : /MPASS.EXE
Uploaded by : sdmonaco <sdmonaco@...>
Description : PCB Gcode Multi Pass Milling Routine


You can access this file at the URL:
https://groups.yahoo.com/neo/groups/pcb-gcode/files/MPASS.EXE


To learn more about file sharing for your group, please visit:
https://help.yahoo.com/kb/index?page=content&y=PROD_GRPS&locale=en_US&id=SLN15398


Regards,


sdmonaco <sdmonaco@...>

New file uploaded to pcb-gcode

pcb-gcode@...
 

Hello,


This email message is a notification to let you know that
a file has been uploaded to the Files area of the pcb-gcode
group.


File : /CSCALE.EXE
Uploaded by : sdmonaco <sdmonaco@...>
Description : PCB Gcode Mill File Scaling Routine


You can access this file at the URL:
https://groups.yahoo.com/neo/groups/pcb-gcode/files/CSCALE.EXE


To learn more about file sharing for your group, please visit:
https://help.yahoo.com/kb/index?page=content&y=PROD_GRPS&locale=en_US&id=SLN15398


Regards,


sdmonaco <sdmonaco@...>

PCB Milling Techniques

sdmonaco
 


Hi Guys!

I have been having very good results with a new PCB milling approach I have been using so I thought I would share it with the group.  The technique is very simple and is very tolerant of dull and/or inexpensive milling tools and does not require auto leveling.

I use Andrew Abken's low cost 30 degree bits from www.drewtronics.net  The 30 degree bits provide the least amount of trace width variation due to PCB thickness variations.

I setup PCB Gcode for single pass isolation and instead of zeroing the z-axis I initially set it to 1 mil above the center of the PCB.  I then etch the traces using this initial setting.  Once complete, I continue to run the trace isolation file lowering the z-axis 1 mill each time.  The technique will usually produce a good clean board after about 2 to 3 etch runs.

Once fully etched, I then proceed to drill and mill the PCB.  Drilling is done normally however I have written a couple of utilities to help with the PCB milling process.  The first routine is called MPASS which takes the PCB Gcode mill output and generates a multi-pass milling file.  I usually generate a 5 pass file which removes 12.4 mils of 62 mil PCB during each pass.  This helps tremendously with tool ware and I never have to use break away tabs.  Yes I do use double sided carpet tape to hold my PCB in place.

The second utility I wrote is called CSCALE.  This program takes the PCB Gcode mill output file and scales it up (or down).  This allows me to use PCB Gcode to design my PCB enclosures and front panels whthout worrying about the 4x6 PCB dimension limits.

I hope this helps with your PCB milling operations and I have added my two utility routines to the files section of the Group.  They are written to run on a standard Windows PC so please let me know if you have any trouble finding or using them.

Thanks, Happy Milling!

Sam


Re: Cutting out the border?

sang kang
 

I use ample double sided tape and will give the excel a try. I think it will work out. Thanks for the file and suggestions.

Re: Cutting out the border?

mlmcnc
 

Danny makes a valid point.
In order to simplify the creation of the border I use the simple Excel spreadsheet I have attached.
Just copy and paste the generated command line to the Eagle command prompt.
As you will see, I use metric. Feel free to modify to suit your needs.

Martin Marriott
mlmSolutions

Re: Cutting out the border?

Danny Miller <dannym@...>
 

Unless you use a vac table or double-sided tape, you usually want to make the Milling line stop/start at a few points to leave tabs.  This keeps the board from being cut free at the end, which makes it bounce around in the pocket in the stock and that can damage the board and the tool.

Danny

On 1/26/2015 1:10 AM, martin312@... [pcb-gcode] wrote:
 

The manual is your friend here. See page 22/23.
Basically, draw lines on layer 46 (milling) for your boards border. The gcode will be on the mill output file.
Bear in mind that the cutter path will exactly follow the lines on layer 46 so make sure you offset them from the board by the cutter radius. It is a good idea to draw the lines in Eagle at the width of the milling cutter that you intend to use. This will show clearly the cutters kerf.


Re: Cutting out the border?

mlmcnc
 

The manual is your friend here. See page 22/23.
Basically, draw lines on layer 46 (milling) for your boards border. The gcode will be on the mill output file.
Bear in mind that the cutter path will exactly follow the lines on layer 46 so make sure you offset them from the board by the cutter radius. It is a good idea to draw the lines in Eagle at the width of the milling cutter that you intend to use. This will show clearly the cutters kerf.

Cutting out the border?

sang kang
 

Hello,


I'm printing multiple copies on a single board, how do I cut out? I don't see any border file on the pcb gcode.

Re: Drilling issues.

sang kang
 

Hello,

I figured it out.
The drill.tap has a tool change and before it issues the tool change, by default(?) it does one inch travel up. My 3020t is 2 inch travel on z axis and I'm already using 1 inch thick wood for a base and .1 inch for stop switch so I am working less than an inch for z axis.

I manually edited the drill.tap and edited the all Z1 to Z0.4

Re: Drilling issues.

Art Eckstein
 

In your setup of the ulp, do you show the drill depth as a negative or positive value???  Another possibility is you have ZHigh set to high??? Shown below is how mine is setup


Ignore my tool change positions as I have a mine setup in a custom post processor, but that may be another area where your having a problem.

Art
Country bubba









Hello,


I noticed when I drill, the mach3 refuse to run because of soft limit is enabled.

However, I don't see this issue when I run the etch.tap.


Both files are generate at the same time. Why does etch works fine but drill stop by the soft limit?

I've disabled soft limit and the z-axis slams against the home switch for drill.tap.


Is there different z travel setting for drill vs etch in pcb gcode setting?

Drilling issues.

sang kang
 

Hello,


I noticed when I drill, the mach3 refuse to run because of soft limit is enabled.

However, I don't see this issue when I run the etch.tap.


Both files are generate at the same time. Why does etch works fine but drill stop by the soft limit?

I've disabled soft limit and the z-axis slams against the home switch for drill.tap.


Is there different z travel setting for drill vs etch in pcb gcode setting?

Re: New to pcb-gcode, just joined yesterday.

sang kang
 

Hello,

I made some mistake in generating the tap file, the drill file has the holes now.
Thanks for everyone's input.

Re: New to pcb-gcode, just joined yesterday.

mlmcnc
 

Hello sangraikang

I have been trying to think why are you are seeing the problems you are with the limited information at our disposal.
You state that all your traces are on one side.
You don't say whether the board is for surface mount components but as you are talking about drilling holes I will assume that it is not surface mount and is for through hole components.
The clue to your problem is in your statement "the traces are there for top.etch.tap". If it is a single sided board for through hole components, there should be no tracks on top.etch, all the tracks should be on bottom.etch. It sounds to me that you have drawn the tracks in Eagle on the top layer (layer 1). They should be drawn on the bottom layer (layer 16). All your tracks should be blue, not red.

The files that you need are bottom.etch and bottom.drill so that you will cut and drill your board without moving it.

Art has explained why you probably didn't get the top.drill file.

Forgive me if I have misunderstood. If I guessed correctly, I hope it helps.

Yours
Martin Marriott
mlm Solutions.


Re: top.drill.tap has no drill holes.

sang kang
 

that doesn't make sense, if the drill hole is in the bottom file in mirror flip, that means I have to flip the board and realign and run the drill tap file just to drill?

Re: top.drill.tap has no drill holes.

Art Eckstein
 

Have you requested in the setup ulp to do top drill as noted below?



also, to no generate botom drill, uncheck the "Generate bottom drills as noted above.



Art
Country Bubba



At 02:33 PM 1/23/2015, you wrote:


Single sided pcb in Eagle V7.2, I ran pcb gcode and there are no drill hole data on the top.drill.tap. Instead, I'm seeing it on bottom.etch.tap file that is mirror flipped.


What am I doing wrong? Also, is there a tool to unflip the bottom.etch.tap so I can get the hole drilled the correctly on the top side?

Re: top.drill.tap has no drill holes.

Dan Whittemore
 

Hi, 
I believe this is correct  I do mostly single sided boards and the Etch and Drill are always the bottom files.  Check your setup and make sure things are correct there.

On Fri, Jan 23, 2015 at 12:33 PM, sangraikang@... [pcb-gcode] <pcb-gcode@...> wrote:
 

Single sided pcb in Eagle V7.2, I ran pcb gcode and there are no drill hole data on the top.drill.tap. Instead, I'm seeing it on bottom.etch.tap file that is mirror flipped.


What am I doing wrong? Also, is there a tool to unflip the bottom.etch.tap so I can get the hole drilled the correctly on the top side?


top.drill.tap has no drill holes.

sang kang
 

Single sided pcb in Eagle V7.2, I ran pcb gcode and there are no drill hole data on the top.drill.tap. Instead, I'm seeing it on bottom.etch.tap file that is mirror flipped.


What am I doing wrong? Also, is there a tool to unflip the bottom.etch.tap so I can get the hole drilled the correctly on the top side?

New to pcb-gcode, just joined yesterday.

sang kang
 

Hello,


I've just joined this group.

Just learning how to use pcb-gcode.


One question, I am working on a project and managed to put all my trace on one side.

When I generated the tap files, the traces are there for top.etch.tap but the top.drill.tap is missing all the holes. When I looked at the bottom.etch.tap it has all the holes in mirror flipped.


So I'm stumped as to why it's giving me the hole in the bottom.etch.tap and not top.drill.tap. If there's no way to fix this, is there a tool to mirror flip the bottom.etch.tap so I can drill it the right way?

Re: Get symbol to output to top text file

scott.goldthwaite@...
 

That makes sense, I'll give it a try.