PCB board and Bits /recommendations and suppliers

[Fivetide]

Has anyone found a good pcb board for milling and supplier? Also the same goes for bits and drills, and what others have used and found they would recommend, I ‘m only going to do CMOYS’s the are tiny headphone amps mainly for my own production. I’ve been loads of tutorials but none actually say what board they use , they do recommend software and some say what tools.

I 've seen this type of board from CPC (http://cpc.farnell.com/kelan/149055/pcb-plain-s-s-100x220mm/dp/PC01273) wonder if anyone has used it ?

[irving2008]

Has anyone found a good pcb board for milling and supplier? Also the same goes for bits and drills, and what others have used and found they would recommend, I ‘m only going to do CMOYS’s the are tiny headphone amps mainly for my own production. I’ve been loads of tutorials but none actually say what board they use , they do recommend software and some say what tools.

I 've seen this type of board from CPC (http://cpc.farnell.com/kelan/149055/pcb-plain-s-s-100x220mm/dp/PC01273) wonder if anyone has used it ?

I've successfully used 1.6mm double sided FR4 board with 300 - 400gm/sq cm copper (thats around 0.04mm thick) per side. In small sizes (Eurocard, e.g. 100x 220) it stays reasonably flat. I wouldn't use single sided as I think it tends to curl slightly and that makes it hard to get good resolution on fine lines. Also a lot of the stuff I do needs a ground plane anyway so single sided is pointless. The bit I've used is a 90deg v-bit from here (http://www.thinktink.com/stack/volumes/voli/store/mechmill.htm) though i got it locally off ebay and not used it enough yet to need to consider a replacement...

[HankMcSpank]

I 've seen this type of board from CPC (http://cpc.farnell.com/kelan/149055/pcb-plain-s-s-100x220mm/dp/PC01273) wonder if anyone has used it ?

I'm unfeasibly tight (e.g. rather than move to a large house with a gravel drive, I simply glue rice krispies to my car tires) ....I would therefore never use my modest CNC machine to mill PCBs if I had to pay that for my copper board!

I use the paper based stuff (far nicer to work with...and whole lot cheaper)...

Low cost copper clad board (http://www.rapidonline.com/Tools-Equipment/Low-cost-copper-clad-board-32634/?sid=69a12fbd-6b88-4521-8bb7-e4802f16f6ba) ....100mm x 160mm is only 35p per board delivered (if buying 100pcs)

.....however, often it isn't perfectly flat, so I use double sided tape to attach the copper board onto sacrificial waste material (for this, I use nice flat acrylic sourced from a local industrial estate's skip!) to take out the worst of any bowing ...I then use CNC-USB CNC software to do the cutting. This software has a cool built in utility which probes the surface first and then takes account of probed peaks & troughs to adjust the Z height as it goes about it's isolation milling. I use 30 deg 0.2mm tip carbide V cutters from China...they're fine for my needs. (about a tenner for 10)...I can go as low as SOT23-6 (which is about 0.6mm between consecutive pads) ....I'd be able to go lower if my machine had ballscrews, but it just uses standard 1.5mm pitch threaded rod.....one day

[Fivetide]

I'm unfeasibly tight (e.g. rather than move to a large house with a gravel drive, I simply glue rice krispies to my car tires) ....I would therefore never use my modest CNC machine to mill PCBs if I had to pay that for my copper board!

I use the paper based stuff (far nicer to work with...and whole lot cheaper)...

Low cost copper clad board (http://www.rapidonline.com/Tools-Equipment/Low-cost-copper-clad-board-32634/?sid=69a12fbd-6b88-4521-8bb7-e4802f16f6ba) ....100mm x 160mm is only 35p per board delivered (if buying 100pcs)

.....however, often it isn't perfectly flat, so I use double sided tape to attach the copper board onto sacrificial waste material (for this, I use nice flat acrylic sourced from a local industrial estate's skip!) to take out the worst of any bowing ...I then use CNC-USB CNC software to do the cutting. This software has a cool built in utility which probes the surface first and then takes account of probed peaks & troughs to adjust the Z height as it goes about it's isolation milling. I use 30 deg 0.2mm tip carbide V cutters from China...they're fine for my needs. (about a tenner for 10)...I can go as low as SOT23-6 (which is about 0.6mm between consecutive pads) ....I'd be able to go lower if my machine had ballscrews, but it just uses standard 1.5mm pitch threaded rod.....one day

Thanks for the replys and wow that is cheap I will be looking into that for sure and the cutters on ebay.

[richie00boy]

Yes that board is really cheap. Is it 1.6mm thick or more like 1.0mm?

Can you link me to where you get the 30 deg bits from please? As I'm currently paying a tenner each. I'm assuming they are not the flat blade type of thing that seem to be listed on ebay? Mine are the pointy type, i.e. proper V shaped.

[HankMcSpank]

Yes that board is really cheap. Is it 1.6mm thick or more like 1.0mm?

Can you link me to where you get the 30 deg bits from please? As I'm currently paying a tenner each. I'm assuming they are not the flat blade type of thing that seem to be listed on ebay? Mine are the pointy type, i.e. proper V shaped.

I've just measured the board thickness - it measures just over 1.6mm thick. Being paper based (btw, don't let the sound of that put you off, it's extremely strong - but is is very brittle so don't be going bending it too much), I find inhaling the inevitable dust thrown up a far more enjoyable experience vs. fibre glass particles (I had an unexplained lung abscess a couple of years ago, which developed into pneumonia....I can't but help thinking it was fibre glass dust becuase just a couple of weeks prior, I'd had an FR4 milling frenzy!)

Here's an example of the bits I'm sourcing from ebay (not sure if it's the exact seller, but they're all much of a muchness)...

10 Carbide PCB Engraving Bits CNC Tool 30 Degree 0.2mm | eBay (http://www.ebay.co.uk/itm/10-Carbide-PCB-Engraving-Bits-CNC-Tool-30-Degree-0-2mm-/130408480428?pt=UK_Home_Power_Air_Tools&hash=item1e5cf37eac#ht_2240wt_906)


These normally come with either 0.1mm end or 0.2mm tips - obviously 0.1mm gets your tip into finer places....but for my money the 0.1mm tip shreds away too easily...if you're not after SMD type isolation milling, I'd say go with a 45 degree or even 60 degree bit.

[richie00boy]

Thanks. Those are the kind I was meaning, I was concerned they would not give as good a finish as the fluted type I currently use.

Also while searching around the forum, I think you said that those ebay spade ones lasted longer than the fluted one you tried? I've not worn mine out yet, but not done that many boards.

[HankMcSpank]

Thanks. Those are the kind I was meaning, I was concerned they would not give as good a finish as the fluted type I currently use.

Also while searching around the forum, I think you said that those ebay spade ones lasted longer than the fluted one you tried? I've not worn mine out yet, but not done that many boards.

certainly a fresh new spade cutter gives superb results (not sure which of my former posts you refer to about the longevity of the spade type - but I don't recall comparing like for like against fluted bits) ...alas, since I'm forever making schoolboy errors (spade descending way too deep into the board & too fast into the board ...the 30 degree spade cutters don't take too kindly to that), it's hard to be precise how long one would last without my mistakes!.

The other benefit of milling paper based board (aside from the more lung friendly dust) is that the board is more easy going on the cutter...afte all, it's just a skimming of copper on top of paper.