[atferrari]

No experience in CNC at all.

I am a electronics hobbyist from long time and I want to mill make my PCBs with a machine that I have the chance to buy very cheap: a Proxxon modified by Usovo (Germany). I think it is a MF70 Euro 2008.

My questions:

Once I get the machine, what are all the other things I need to obtain to start milling (well, trying to) PCBs? Hardware and software?

Could you mention them in a logical sequence if at all possible?

I understand, from all what I have been reading that going from the CAD to the software driving the engraving machine is the hardest part.

Could you mention (reliable?) free software if at all possible.

Gracias for any help.

PD: BTW, engraving or milling?

[kn6za]

atferrari,

Welcome to the zone!

I will give you my take on getting started cutting your own circuit boards.

Hardware; cutting tools. I use and sell 60deg v-shaped tools for circuit board engraving, check out www.drewtronics.net There are many others selling tools for circuit board work as well, but I think mine are the best Other common angles people use are 30deg, 45deg, and 90deg. The shallower the angle the shallower the point on the tool, witch helps keep the cutting width of the tool uniform over the surface of a board that is not held down perfectly flat, or a machine that does not repeat z-depth accurately. 30deg tools have a delicate tip compared to the 90deg.

You will also need a method of holding the circuit board down flat. This is very important, and can make all the difference when it comes to surface mount boards especially. I use a vacuum chuck, but I have seen people use 2 sided tape, super glue, toe clamps. This will require some experimentation to find out what works best for you and the boards you produce.


Software; to design circuits = eagle : cost is free

Eagle can be tough to get started with, but just devote some time to it and you will find it gets better with time.

Software to convert eagle pcb design into g-code to run your mill = pcb-gcode : cost is free check out the yahoo group for it

http://groups.yahoo.com/group/pcb-gcode/

pcb-gcode works really well, its easy to use and has lots of people using it and supporting questions.


Hope this helps, have fun milling boards, its the best way to produce circuit boards at home in my opinion.

[pminmo]

Take a look at my video: [ame="http://www.youtube.com/watch?v=lhdqBrciQZU"]YouTube - Milling a fine trace double sided pcb[/ame] and website millpcbs.com on a simple holding and alignment method. Which BTW uses a Drewtronics bit...:-) At the end of the video you get some still pictures that give you a true perspective of the work.

[kn6za]

One of my FAVORITE online videos

Phil is always working on something cool.

Being able to make circuit boards like that at home is just amazing. Makes prototyping with surface mount components much easier.

[atferrari]

I am not native in English so I do not know what is the actual difference between milling and engraving. Which one is used to produce the PCBs? (BTW, in jewelry?)

What is the main difference in the bits used for each process? Any easy way to recognize them?

I expect to have my MF70 in about two months. A lot to be learnt as far as I can see!


In line with my original post: what should be the minimal set of bits to buy to cater for test, learning (and mistakes).

How would you express how long they last? Minutes of use, length engraved or...?

Yes, I know they are many questions but I am at level zero here.

Gracias.

[kn6za]

atferrari,


Milling and engraving can mean the same thing. If there is a diff, engraving is milling by removing relatively little material.

For engraving look for small cutters, say 1/8" or less dia.

As far as circuit board work goes, order up some v-point engraving cutters of your choice, say 60deg point angle, and get some drills in the .025 - .04 range. Dont just get one v-point tool, because you will have an accident (drop it?) and then you will wait for a new tool to come before you can finish your project and that is frustrating.

[pminmo]

Dont just get one v-point tool, because you will have an accident (drop it?) and then you will wait for a new tool to come before you can finish your project and that is frustrating.

The very first bit I purchased, a $29 coated precision V bit. Never touched a spindle because I dropped it on concrete while admiring it......tip shattered............:violin: That's before I found Andrews bits, I've been using DrewTronics bits ever sense and never looked back...........

[pminmo]

I just finished a pcb with a Drewtronics bit about an hour ago.

[kn6za]

Phil,

Another super nice board! Did you use super glue to hold it down? Looks like you had it dead flat while cutting it.

[pminmo]

Thanks, yes, super glue and Drewtronics bits is the only way as far as I'm concerned.........

[kn6za]

Phil,


Thanks for the good words, I am glad to hear they are working well for you.

atferrari,

Let us know how your board cutting works out for you.

I hope our suggestions help you out.

[atferrari]

I told it already, yet at level zero, I need to ask some more questions to people who actually do things. THere is a big difference with forums about electronics: here it seems there is much less blah blah blah. GOOD!

a) "Super glue" is a specific type or just a commercial name? What could be the equivalent in the local (Argentina) market?

b) You bond the board to what?

c) How do you separate it after completing the PCB?

d) Have read of people doing the drilling before milling. Any comments?


My MF70 is closer (maybe in 8 weeks I will have it!

I feel like trying to learn basic rocket science with all this. I hope one day my PCBs would look like the one shown some posts below. Wow!

[pminmo]

I told it already, yet at level zero, I need to ask some more questions to people who actually do things. THere is a big difference with forums about electronics: here it seems there is much less blah blah blah. GOOD!

a) "Super glue" is a specific type or just a commercial name? What could be the equivalent in the local (Argentina) market?

b) You bond the board to what?

c) How do you separate it it after completing the PCB?

d) Have read of people doing the drilling before milling. Any comments?


My MF70 is closer (maybe in 8 weeks I will have it!

I feel like trying to learn basic rocket science with all this. I hope one day my PCBs would look like the one shown some posts below. Wow!

Super Glue is a trade name for cyanoacrylate glues (CA): (http://en.wikipedia.org/wiki/Cyanoacrylate) There are many, many, many trade names and viscosities. I just buy the cheapest I see, usually in small tubes in a quantity at a discount store. Using a thin CA, (which is like water) and placing a few dots on the revese side of the pcb to be milled it is then glued to a piece of flat aluminum plate, tooling plate. Tooling plate is aluminum that is ground to a mirror flatness. I bought mine from ebay. CA debonds with acetone. I drill before I mill as I also use alignment pins for exact registration. By making the drills for the alignment pins part of the design process, you have perfect registration from side to side and operation to operation. See Fixtures and Tooling on my website: http://millpcbs.com/ If you want to look at something to give you how capable you can be with more technique than expensive equipment see my video: [ame="http://www.youtube.com/watch?v=lhdqBrciQZU"]YouTube - Milling a fine trace double sided pcb[/ame] Make sure to see the pictures at the end to get a size perspective.