Spindle power for PCB milling

[rbasniak]

Hi,

I don't know if I'm posting on the right forum. There are too many, so I'm sorry if it's an off-topic here.

I'm building a pcb milling machine but I'm confused on what motor show I use. Can someone help telling me where do I get this kind of information?

It's a pcb only machine, so for what I've seen cutting forces are low, and rotation used lies aroud 20.000rpm. But what torque do I need?

Thanks in advance,
Rodrigo Basniak

[kn6za]

In my experience the drilling has required more torque than the trace issolation milling. Also if you plan on routing out the edges of your board, that can take even more torque, but even at that 200watts should be a good starting point I think.

My spindle is 2000watts, but its total overkill for pcb routing.

[rbasniak]

Thank you Andrew...

I've found some home made projects over the internet which lies around the 200W value, but all of them are meant to mill other materials as well. I'm not planning on milling the edges, only the traces, so I think 200W will be totally overkill.

I think the torque required will depend only of the cutting forces involved, so I'm trying to find some resources on how to estimate it for a PCB milling.

If anyone has some ideas, I would be grateful

Best regards,
Rodrigo Basniak

[Kipper]

Maybe an 80W sewing machine motor and a diy spindle would be fine for isolation routing....I'd give it a go!

[eSilviu]

Hi,

I don't know if I'm posting on the right forum. There are too many, so I'm sorry if it's an off-topic here.

I'm building a pcb milling machine but I'm confused on what motor show I use. Can someone help telling me where do I get this kind of information?

It's a pcb only machine, so for what I've seen cutting forces are low, and rotation used lies aroud 20.000rpm. But what torque do I need?

Thanks in advance,
Rodrigo Basniak

I've done-it with 20W or power, pushed on a RC outrunner motor.
Milling and drilling.
Cutout will eat probably 40-50W.
See here: Home build CNC mill/router

[rbasniak]

Thanks a lot for your reply eSilviu, I have bought some 30W DC motors that I'll be running some tests now... I hope to be posting some pictures of my machine in a few weeks...

Best regards....

[lrm72]

Hi, even 30W are enough for insulation, cutout, etc. I know this, because some of the LPKF machines have such spindle. According to me, the base problem of the spindle is not the power, but the rpm (at least 30000).

[eSilviu]

Hi, even 30W are enough for insulation, cutout, etc. I know this, because some of the LPKF machines have such spindle. According to me, the base problem of the spindle is not the power, but the rpm (at least 30000).

high RPM are desired, but a compromise will be made.
I have never used my (echivallent of) Dremmel faster than 20.000RPM.
for milling PCB I use-it at about 170V; for drill - 120V; for cutout - 190-200V
(electronic circuit from tool has given away it's magic smoke after only a few hours of usage, and now I use an auto-transf. to modify speed)
Tool it's rated 230V, 120W, 30.000RPM.

[rbasniak]

I found 30W @ 25.000rpm.

I'll be posting results as well as some pictures of the machine soon.