Making solar tracker. First time milling PCB, requesting help.

[Burnit0017]

Greetings to all. I am new to the forum. The cold weather is preventing working outside on other projects. I am currently working on a solar tracker. I have completed the motor control circuit and would like to try fabricate the pcb’s using my Zenbot. I am using ExpressPCB to layout the board. It will allow a dxf file to be created but it does not include the trace pattern. I use TurboCad to redraw the trace pattern. Then I use LazyCam to create the g-code. I run the Zenbot using Kcam and I have cut many usable parts with it but this is my first attempt at making my own pcb. I am able to draw the traces for a 2 sided pcb . If anyone can share there experiences making a two sided pcb , how to keep both sides lined up, is there a Dremel bit that can be used, or free download software that would make the process easier? Please let me know.

[kn6za]

Burnit,

Sounds like a great project.

For circuit milling bits check out www.drewtronics.net I use the 60 deg bits mostly.

When milling your first side of a board it helps to drill 2 holes through your board and into a spoiler board below, then when you flip the board over you can place pins in the holes to align the board for the next side, this works really well, but there are lots of other ways, I am sure others will share their ways with you.

Also google pcb-gcode for eagle if your interested. I know your not using eagle to design your board, so this may not be any help to you, but alot of folks are making their boards with that combination.

hope this helps!

[H500]

I am curious about your circuit. What prevents both transistors on the same side from turning on simultaneously and destroying the fets?

As for PCB milling, have you tried toner transfer instead? I find it to be less effort and can do fine pitch (8 mil) double sided boards with ease. If you use copper chloride for etching, then there's also no costly consumables.

[gmfoster]

Greetings to all. I am new to the forum. The cold weather is preventing working outside on other projects. I am currently working on a solar tracker. I have completed the motor control circuit and would like to try fabricate the pcb’s using my Zenbot. I am using ExpressPCB to layout the board. It will allow a dxf file to be created but it does not include the trace pattern. I use TurboCad to redraw the trace pattern. Then I use LazyCam to create the g-code. I run the Zenbot using Kcam and I have cut many usable parts with it but this is my first attempt at making my own pcb. I am able to draw the traces for a 2 sided pcb . If anyone can share there experiences making a two sided pcb , how to keep both sides lined up, is there a Dremel bit that can be used, or free download software that would make the process easier? Please let me know.

You might want to look into PCBGCODE as it works to create the milling paths directly with eagle..

http://www.pcbgcode.org/

Garry

[Burnit0017]

Greetings, the back to back and then vertical placement of the sensors sets is what should allow the circuit to work. A project in Berkeley is using the technique. The video shows how to mount the sensors far better than can possibly explain it.

"http://www.youtube.com/watch?v=iH49Xd_NV3A"]YouTube- Solar Tracker (Berkeley ME102 Project)

[Burnit0017]

I am curious about your circuit. What prevents both transistors on the same side from turning on simultaneously and destroying the fets?

.

Greetings, the back to back and then vertical placement of the sensors sets is what should allow the circuit to work. A project in Berkeley is using the technique. The video shows how to mount the sensors far better than could possibly explain it.

"http://www.youtube.com/watch?v=iH49Xd_NV3A"]YouTube- Solar Tracker (Berkeley ME102 Project)

[Drools]

Very cool demo, looks like an interesting project. I would look at eagle as well, I'm not sure how big your circuit board is but the free version might do what you need.

[Burnit0017]

I tried some test cuts on a blank board and the results where dismal, aka not good. Some parts of the traces cut to deep and other parts not at all. I definitely have to fabricate a better fixture. It did show that the software and procedure I used does work, but there is a lot of room for improvement. All in all a good learning experience. I am checking out the Eagle software.

[Burnit0017]

When making modifications to a pcb layout I noticed a way to make less cuts. The patterns are the same circuit. The one on the left requires less cuts.

Can anyone suggest a simple Font that can be used on a pcb layout?

[Jay C]

You should look into the pcb-gcode and Eagle. What size bit are you coding for? make sure you give yourself enough isolation to avoid solder bridges. I personally like 20mils isolation on my circuits.

Jay

[Burnit0017]

You should look into the pcb-gcode and Eagle. What size bit are you coding for? make sure you give yourself enough isolation to avoid solder bridges. I personally like 20mils isolation on my circuits.

Jay

Greetings, I have some small Dremel bits that I am trying to use until I purchase something better. I am currently fabricating a fixture to hold the pcb. I read in another post to mill the fixture flat first after it is installed to insure it is parallel with the cutting bit. After that we be ready to try another test cut. Thanks and best regards.

[Jay C]

Perpendicular Yes, surfacing is the best way to get a flat surface relative to the spindle. Also, when you mill, make sure the copper is fully supported. I use carpet tape under my boards to hold them. Are you also trying to use a Dremel? They are notorious for runout that makes using them for smaller traces an iffy proposition, and a danger to more expensive micro bits. The least expensive bits are also my favorites are from www.drewtronics.net.