CNC PCB Engraving Machine

Hi,

As of last night I am the owner of a Denford PCB Engraving machine : http://website.denford.ltd.uk/news-menu/117-denford-s-pcb-engraver

Unfortunately, it didn't come with the (£600...) dust / swarf extractor (page 22 here: http://www.denfordata.com/pdfs/product-literature/pcb-engraver.pdf)

I'm hoping that, with a little help from the right adaptor, I should be able to rig up one of these in place of a DP-50: http://www.ebay.co.uk/itm/SIP-01929-Workshop-Dust-and-Chip-Collector-Extractor-Hose-Adaptor-Set/381144608665?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122125356%26meid%3D9b344a747a7c416682d9150656a4f826%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D201047854976&rt=nc

If the speed needs adjusting then I can use a variac - I doubt the extractor will have a switching / regulated PSU.

Has anyone here got experience with such an engraving machine? I notice in another thread that Jakob has picked up an LPKF machine. Is its function similar to mine? What else does it do, aside from routing + drilling?

Have you managed 2-layer PCBs? How did you plate the vias?

Aside from being extremely patient (the previous owner of this machine wasn't - and was quite honest, hence his sale), what advice would you give me?

thermionic said:

Have you managed 2-layer PCBs? How did you plate the vias?

Click to expand...

At my day job, we use a BEL Favorit to plate vias. First it takes a lot of time to punch every via by hand, then you have to use huge via sizes (0.9 mm), but the best thing about it is, that these loose connectivity after a while. So to save yourself from searching for the bad via, you have to solder each one from both sides.

Overall, I wouldn't recommend this option. I think using resistor legs or wires for vias is a lot cheaper and more reliable.

Best,
Carsten

I have been toying with the idea of getting something like this for a long time. It looks like prices are starting to come done a bit. One thing I could not find was a figure for the largest size PCB this would handle. A lot of the cheap machines can only handle small PCBs but this one looks quite substantial. Do you know how big a PCB it can handle?

I notice it can also engrave acrylics. Can it also engrave aluminium - this would be ideal for prototype front panels. and of course the other good thing is that is is British.

At present I use Iteadstudio for prototype PCBs. They are very cheap but it takes at least 3 weeks to turn around. You get 5 or 10 boards but if your layout has any errors that's a lot of scrap boards. Even so, it takes a lot of Iteadstudio PCBs to get anywhere near the cost of this type of machine. Still undecided.

Cheers

Ian

Taken from Denford PDF:

Travel X Axis 330mm
Travel Y Axis 210mm

Click to expand...

Assuming that their definition of 'travel' is measured by the maximum excursion of the drill head itself, then I'm going to assume that's the maximum PCB size it'll cater for.

Seeing as I haven't even had a chance to plug it in yet, I'm hardly an authority!

It sounds like PTH boards are hardly  worth it - as you say, a lead will do the job, Thanks

thermionic said:

Taken from Denford PDF:

Travel X Axis 330mm
Travel Y Axis 210mm

Click to expand...

Assuming that their definition of 'travel' is measured by the maximum excursion of the drill head itself, then I'm going to assume that's the maximum PCB size it'll cater for.

Click to expand...

That's the thing. The head usually has to move out of the way so you can get the PCB in and out so in many of the others I have looked at the biggest PCB is rather smaller than the maximum travel. My double eurocard sized PCBs are 234mmm by 160mm. Also, the 6U panels I would like to engrave are 267mm tall. I guess my best bet is to ask them.

Cheers

Ian

I'm not sure which ones will cater for that size of PCB, Ian, but I take it that you're aware of how many machines there potentially are on Ebay?

The issue I have with the Denford is that I can't find any threads / usergroups for it on the web. Although being made in the UK is a plus point, and the company seem perfectly pleasant, you may well find an imported machine for a fraction of the price that's popular with Arduino hackers. That would give you access to lots of usergroups / tips etc.

thermionic said:

I'm not sure which ones will cater for that size of PCB, Ian, but I take it that you're aware of how many machines there potentially are on Ebay?

Click to expand...

I have not looked for them on Ebay for a long time. They certainly seem to have come down in price and some even ship from the uk:

http://www.ebay.co.uk/itm/New-CNC-3040-Professional-4-AXIS-Router-H80mm-Engraver-PCBS-Routing-Machine-/290940824902?pt=LH_DefaultDomain_3&hash=item43bd6cad46

Only odd thing is they all seem to need a parallel port. Do any PCs have one of those any more?

Cheers

ian

I spotted the requirement for a parallel port. It's probably based on some really old code that takes a parallel printer driver and rasterises it to drive the CNC

I'd be looking for something with USB or Wifi - then at least it might have some code in it that's not more than ten years old

Parallel port printing pretty much rules out using it on a Mac

Nick Froome

parallel port is still the simplest way of guaranteeing real-time performance.

Jakob E.

Get this: the Denford is sufficiently modern enough to operate via USB. However, the key for its software is supplied on a...

...wait for it...

...floppy!

I now have to buy a floppy drive in order to install it. At this point I suspect the Denford is unlikely to be a simple plug-and-play device.  I hope I am proven wrong.

I got my CNC wired via parallel, too. But if I would buy a new machine today, i'd choose something with USB.

...markus

I was wondering why Parallel, so did a bit of research.  I used to come across parallel port printing in a Macintosh environment when people used external RIPs or plotters.  It was a nasty, awkward kludge and I was pleased when it went away. The reason for it was to take a file generated by Quark, which was full of Postscript Fonts, which are basically vector descriptions of a font shape, and rasterize it to create a file that can be thrown straight at an imagesetter, or drive an XY plotter from VectorWorks, etc

I don't know if the parallel-based plotter packages work the same way or not but I imagine the CAD files used to drive them must be vector-based and the signal sent to the CNC must be rasterized so a similar conversion is going on somewhere

There is a huge CNC forum here:
http://www.cnczone.com/forums/

There is a specific section for interfaces here
http://www.cnczone.com/forums/usb-rs232-parallel-etc/

Nick Froome