Full Version: Copper Engraving
From: kkilaser [#1]
15 Feb 2007
To: ALL
I have a Roland EGX-400 engraver and was wondering if someone could give me some tips on engraving copper plate, such as spindle speed, engraving speed, depth, and any other tips you can think of.
Thanks in advance.
Don Ancona
KKI Laser Services
602-438-6500
EDITED: 15 Feb 2007 by DGL
From: Stunt Engraver (DGL) [#2]
15 Feb 2007
To: kkilaser [#1] 16 Feb 2007
From: kkilaser [#3]
16 Feb 2007
To: Stunt Engraver (DGL) [#2] 16 Feb 2007
David,
The copper pieces are about 1/8" thick. No color filling, just engraving text using a single line font only as deep as necessary to read the text.
Thanks,
Don Ancona
KKI Laser Services
602-438-6500
From: Stunt Engraver (DGL) [#4]
16 Feb 2007
To: kkilaser [#3] 16 Feb 2007
From that description, it sounds like a non-rotating, diamond drag method will suffice.
Of course, with that method, the line width won't be very heavy. Depending on how much downward pressure you can exert, approx. between .005-.010 wide.
How tall are the characters going to be?
If you need a heavier line width -- which you'd want, for bigger letters -- a rotating burnisher would be a better way to go.
Burnishers come in various widths and are designed to ride on the surface of the material. If you go that route, I'd recommend diamond burnishers, as opposed to carbide. They last much longer and allow you to engrave softer materials, i.e. aluminum.
I would go as far to say (although I have no experience with burnishing copper) that copper, because of its softness, will require a diamond burnisher.
I'm speaking in general engraving terms, because I know very little about the Roland engraving systems, in particular.
We do have a few people who use them, and they may be able to address the finer points, re: how to adjust pressure, and other operating procedures.
EDITED: 16 Feb 2007 by DGL
From: Stunt Engraver (DGL) [#5]
16 Feb 2007
To: kkilaser [#4] 16 Feb 2007
Looks like you read my post, while I was editing it, to elaborate on burnishers.
From: kkilaser [#6]
16 Feb 2007
To: Stunt Engraver (DGL) [#4] 16 Feb 2007
David,
I am planning to use a CleanCut cutter which is like a half-round from Antaries, rotating, with a .015 tip. The letters are about 1/8" tall. I have never used a burnisher before and I have never tried to engrave into metal. I'm just not sure what speeds to use.
Thanks,
Don Ancona
KKI Laser Services
602-438-6500
From: Stunt Engraver (DGL) [#7]
16 Feb 2007
To: kkilaser [#6] 16 Feb 2007
Don,
Does your machine have a nosecone depth regulator?
What they do, is ride on the surface of the material and allow the tip of the cutter to protrude, to a predetermined depth.
Without a depth regulator, you'll have a tough time achieving a consistent-looking character.
The speed (RPM) of your motor won't be as crucial a factor as the speed at which you have the cutter work through the material, which, for metal, should be fairly slow. You'll know you're moving too fast, if the tip of your cutter snaps off. >.<
Also, keep in mind, that since the nosecone comes in direct contact with the metal, it will scuff the surface of the metal.
No problem if the metal is unfinished. You can lightly sand the plate to render a brushed finish.
If the surface is finished, (polished, lacquered) you can apply a thin piece (.025) of plastic engraving stock, over the engraving area, with an adhesive spray, which will allow you to engrave through that top layer, while protecting the copper plate.
EDITED: 16 Feb 2007 by DGL
From: kkilaser [#8]
16 Feb 2007
To: Stunt Engraver (DGL) [#7] 16 Feb 2007
David,
Yes I have a nose cone depth regulator. Thanks for all the information. We'll see what happens.
Don
KKI Laser Services
602-438-6500
From: Stunt Engraver (DGL) [#9]
16 Feb 2007
To: kkilaser [#8] 16 Feb 2007
Don,
Good luck. Engraving into metal, as well as color-filling engraved metal is a niche area.
Not a lot of competition there and for good reason to those who aren't up to the nuances of the learning curve.
Once you have it figured out, I say, "Pedal to the metal!"
EDITED: 16 Feb 2007 by DGL
From: Andrew [#10]
16 Feb 2007
To: Stunt Engraver (DGL) [#9] 16 Feb 2007
Hi Don
Not much to add to the good advice already given. Little experience of copper - my day to day work is brass, and I haven' used a Roland, but as you are going to be rotary engraving it:
I would use a fairly high rpm with the smallish cutter tip. I use 16000 - 18,000 rpm with small cutters
To start with set the feed rate at the low end of what you machine is capable of (you can try increasing this a little later when you are getting good results)
I buy Vinyl to place over the engraved area of polished metals - this completely eliminated the potential for ghosting from the nose cone and I find it fairly easy to take off. (I buy in 50M rolls just for this as I use a lot of it.)
Use a vacuum on the nose cone if possible too.
If you are going to deep engrave it, take two passes.
If you find you are getting a burred edge to the engraving, you may find your cutter angle is wrong for metal. I use a 30 degree cutting angle on brass and this seemed to work well on the few occassion I came across coppers & bronze
Some say to use a lubricant on copper.
If you are getting a good result, and you are going to be doing a lot of this, you can then start to increase the feed rate of your machine to improve your output.
Regards
Andrew
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