Full Version: Copper Engraving
From: Stunt Engraver (DGL) [#11]
16 Feb 2007
To: Andrew [#10] 16 Feb 2007
The vinyl is a good tip. I've even used wide pieces of masking tape and gotten away with it
but something more durable, such as vinyl, would inspire more confidence.
From: Rodney Gold (RODNEY_GOLD) [#12]
16 Feb 2007
To: ALL
The key to succesful copper engraving lies more with the cutter and with a lube fluid.
Speeds and feeds are difficult to predict for the machine, however you can set a good compromise by ear.
Copper must be engraved fairly fast in terms of feed rate and I would set a midrange feed , then to get it right you can vary your spindle speed till you hear a "sweet" spot. Thats it!
I would start with a feed rate about 1/3rd less than you would use for plastics. The EGX is not a high torque high power spindled machine ,so generally the depth of cut you can take is about 1/3rd the tip width of the cutter. In tems of width to height for single line letters , 7 or 8:1 is the rule. IE a 1" letter nheeds an 1/8th wide cutter.
The LAST thing you want is to put any significant heat into the material , so a coolant lube is required. The best is a water soluable machining oil like Dromus or Diatsol (BP and Shell) , the coolant will do many things , it will stop clogging of the bit , allow you a faster and deeper cut. Use it undiluted and painted/dribbled on the piece. It washes off after with no sticky residue.
Now for the MOST important thing , the bit you need to use needs to be ground with a LOT of back clearance to allow for chip removal , if not the swarf rubs and generates heat and clogs the cutter and give a bad edge , burrs or worse.
So either use a 1/4 ground bit or take away a lot of the back and the non cutting edge of the cutter. A standard cutter will not work well in this case , you HAVE to grind correctly. (A cutter that works on soft aluminium will do).
Apart from this a bottom loading cutter that protrudes as little as possible will be superior to a top loading cutter , AFAIK you can get a bottom loading collet for your machine (less cutter flex and chatter)
You should have leveled the table of your EGX (there are instructions on how on rolands site) and thus shouldnt have to use a nose cone to get consistent depth if the copper is flat.
EDITED: 16 Feb 2007 by RODNEY_GOLD
From: John (JOHNRMONTG) [#13]
16 Feb 2007
To: kkilaser [#1] 16 Feb 2007
Hi Don ... I will probably not be of a lot of help here but I have a Roland EGX 300 and I have probably engraved just about every other kind of material. When I first got it and had already learned of this forum I asked for help and probably the best advice I got was to get a piece of scrap material and 'give it a try'. I, like Stunt Engraver, I would probably recommend a diamond engraver or possibly a diamond burnisher, depending upon how deep you are going to need to go to get the look you are trying to achieve.
I assume you have already used the machine quite a bit so won't need any of my help in regards to your settings but if so, let me know.
From: kkilaser [#14]
16 Feb 2007
To: John (JOHNRMONTG) [#13] 19 Feb 2007
To All,
Thanks for all the good information. I did some preliminary tests allready and am having good luck so far. So far a spindle speed of 20,000 and feed rate of 15mm seems to be working well and I am going shallow with just one pass. Thanks again for all the good advice it's been very helpfull. In fact this forum is the best I've belonged to. Hope everyone has a good time in Vegas at the ARA show, my wife and I will be there on thursday and friday.
Thanks,
Don Ancona
KKI Laser Services
602-438-6500
From: Andrew [#15]
16 Feb 2007
To: Stunt Engraver (DGL) [#11] 16 Feb 2007
but something more durable, such as vinyl, would inspire more confidence. .
Hi David
the vinyl also serve a dual purpose for me . If I am say engraving a 100 tags, I will lay a tacky mat on my bed, then a matrix made from a sheet of flexible plastic that I have routed out the shapes of the brass tags. Lay out the tags and then place the Vinyl on top. Sounds a bit of an ordeal but it works really well when deep engraving the brass.
My wife isn't impressed with the gold vinyl that I seem to trail everywhere - perhaps its time to use a new colour!
From: Stunt Engraver (DGL) [#16]
16 Feb 2007
To: Andrew [#15] 16 Feb 2007
Still using those Autumn colors. I don't blame your wife. :-)
EDITED: 16 Feb 2007 by DGL