## Characterize the specifications of your PCB production process # Author : seunghwan-ji ![1](img/group/week5-group/1.jpg) This is pcb milling machine we use. It’s name is BANTAM now, which is other mill before.<br> Extensions supported by BANTAM are EAGLE (.brd), Gerbers, SVG (.svg), G-code (.nc, .tap, .gcode).<br> different to other milling machine like Roland, it has electronic tool length measuring function.<br> ![2](img/group/week5-group/2.jpg) This is the material we use it called FR1.<br> It has thin copper on the top to flow electricity.<br> And phenolic paper under copper foil.<br> We used double sided tape to secure copper board to sacrificial bed.<br> ![3](img/group/week5-group/3.jpg) FR4 is double-sided copper board and it has glass fiber fabric between copper foils.<br> It’s stronger to heat than FR1 but you should be careful to not inhale glass fiber dust.<br> ![4](img/group/week5-group/4.jpg) These are tools we use for milling PCB board.<br> We use 1/64inch end mill to cut trace and 1/32 inch to cut outline.<br> And these endmill have different shank diameter.<br> we should use proper collet to each shank diameter to hold the tool tight.<br> And cut length is related to cut depth. We should use longer tool than cut depth.<br> ![5](img/group/week5-group/5.jpg) ![6](img/group/week5-group/6.jpg) ![7](img/group/week5-group/7.jpg) When we set tool on the machine we should measure the tool length.<br> And this process is essential every time you change the tool.<br> When we change the tool and set tool on program, it automatically start tool measuring.<br> It moves to right part of sacrificial board and slowly goes down.<br> When the tool touches the board and electricity goes though and stop.<br> ![8](img/group/week5-group/8.jpg) ![9](img/group/week5-group/9.jpg) ![10](img/group/week5-group/10.jpg) ![11](img/group/week5-group/11.jpg) Each material has slightly different thickness.<br> So we should measure material thickness using Bitbreaker tool.<br> When we push Bitbreaker, we can set the location.<br> Measuring the part you will cut is better because FR1 board has slightly different thickness on each part.<br> There is black metal clip. When measuring material thickness clip should be on the material to flow electricity though the copper surface.<br> ![12](img/group/week5-group/12.jpg) ![13](img/group/week5-group/13.jpg) When we open .nc extension file created by fabmodule program show simulate image.<br> And we can set placement avoiding used part. So we left this paper beside to machine.<br> So that everyone using machine can set the unused placement.<br>