Hi Folks,

This is for a voltage controller I am working on.

It is a basic variable voltage power supply based on the LM317 voltage regulater.
What it does is allow me to set a minimum and maximum output voltage to drive
a string of LED's at varying brightnesses.

I inked in the cut grooves with a sharpie so the CB would photograph better.
I sanded the the surface of the CB to get rid of burs and fuzz.
I am going to order a finer line engraving bit than the one I have.
With that I should be able to read the lettering clearly.
The CB dimensions are 1.2" x 1.4". the lettering is 1/16" high.



The entire circuit design, render, and cutting was done in Rhino 3D & RhinoCam.
This is a render of what the finished CB with parts will look like.


This is a screen capture showing all the parts laid out in Rhino 3D top view.


My Phlatprinter 3 does an excellent job, and is dead nuts accurate when cutting
with the combination of RhinoCam and the USB-CNC controller.

This design is still a work in progress. I still need to find a thin material to fix the
copper clad board to. On some of the prototype engravings the cutting tool tends to
move the part around on the 1mm backing foam. The foam tend to stretch a little
during machining. The copper clad is held to the foam with #77 spraymount.
I am still looking for a better cutting tool for engraving copper clad board.

I will post a copy of the CNC file as soon as I have the final version tested.
If anyone has any suggestions or thoughts, please post them here.

Hope everyone finds this interesting.
Cheers.
GHB Attached files

 

thunder hawk, I saw a post on the CNCZone where a guy made his own cutting tool, for cutting PCB boards, out of a concrete nail. I think it was in this thread, but I'm not sure. http://www.cnczone.com/forums/open_sour ... c_3_a.html

 

Thanks for the tip.

I have a set of Armana InGroove Engraving Tools.

I was thinking about taking a dull router insert blade and reshaping the point to make a
circuit board engraver.

I've been thinking about 8 to 10 deg. per side cut angle.
The inserts are fairly easy to reshape on a grinder.

Any thoughts or ideas from anyone here in the Phlatland is appreciated.

Cheers.
GHB

 

thunder hawk, search a bit in CNCZone in the PCB section. I read there, somewhere, that the cutting bit should be 60°, which makes it 30° per side. If I'll find the picture of how the bit should look like I'll post it here.

 

I don't know if it's any help but I use the 30 degree engraving points for PCB isolation routing on my CNC.

Tweakie. Attached files

 

The advantage of using a 60° but is that you can go less deep to achieve the same width of cut, which may play a roll in a PCB board.

 

The problem I've been having is not with cutters.
I have been trying to find a good backer for the circuit board (CB).
I have been using 1mm Depron foam held on with #77 Spray Mount as a backer.
The bit tends to compress the CB before the bit begins to bite.
Also the bit tends to drag the CB slightly around on the foam.

Oh well, back to the mad scientist lab for me.

Cheers.
GHB . :questions: :think: :jester: :burp: Happy 4th.

 

I had good success using 1/8 plywood sheet as a backer and using locktite 25 (lighter adhesion than 3M 77) as a spray adhesive for 2mm carbon plate. The plywood did not skew on the rollers at all and made a smooth, solid carrier. No bit height variation during the cutting process to deal with either. I did find that it was extremely important to load the material in the center of the pressure rollers. Since I was only using 4" wide x 12" long carbon plate on a 12" wide backer any offset from the center of the pressure rollers resulted in a lot of feed drag and missed steps. At $20.00 a plate it only took one bad cut to really focus in on a viable carrier setup.

:02cents: