cnc engraving recomendations

[werowance]

so I recently purchased a 3018 cnc engraver and just now getting to play around with it a little. I was wondering if anyone had some recommendations for engraving brass or aluminum name tags or say a zippo lighter for example. it came with pointed d bits for engraving. I guess main question is about how deep would you program it to cut if you wanted to put your initals on brass zippo lighter for example ? I know feed rates would vary by machine so my next question is does anyone own a 3018 that could recommend speed for engraving the same test piece? I have some scrap brass sheet I can play with but really didn't want to break any of the dbits right off the bat if I could help it. really just looking for tips or recommendations for this little machine. I see all sorts of videos and such of it running but no real recommendations for what I want to do with it.

 

[kvom]

I assume the engraving bits actually have a flat on the tip rather than a point. I have a set from Bits & Bits with varying size flats. Start with DOC of around .003" and see how you like the result with the various tip sizes. A lot will depend on how flat the brass is. Run max RPM and slow feed to start.

 

[leerkracht]

a carbide radius cutter of diameter 2mm gives very good results , by varying the depth you can adjust the engraving width , start with a depth of 0.001 inch >rpm maximum the higher the better. the feet supply is of course dependent on your rpm, feet per revolution 0.002 inch (cutter with two teeth).

 

[werowance]

dbits to a needle sharp point is what came with it.

 

[myrickman]

I use those 1/8” , 60 degree carbide engraving bits off fleabay. Depth of cut is about 5 thou. The bits are simply a point with half ground away. I run at max 24000 rpm speed, exact stop and about 30 IPM. Here is the result for an engine model I built... I might add that having a work surface which is absolutely flat relative to the cutting plane is imperative.

 

[NickP]

Hi Werowance, I use a spring loaded diamond drag tool. It produces lovely crisp lines and is ideal where the surface is less than perfectly flat and you want to make crisp shallow marks. You use these with the spindle off.
For deeper engraving you’ll need to make several passes or use a pointed tool such as the one you describe. I first thought you meant D bits - used to bore a flat bottom hole to close sizes, but believe you mean the D is a cross section and the tool comes to a point (effectively a single cutting edge tool).
Hope this helps, Nick

 

[--colin--]

https://www.precisebits.com/They have a nice selection of high quality cutters for engraving and sign cutting.

 

[leerkracht]

Not a D-bit but a real milling cutter

https://www.hoffmann-group.com/BE/n...frezen/VHM-graveerfrees-60°-ongecoat/p/208040
https://www.verspaningonline.eu/assortiment/vhm-frezen/micro-frezen/micro-radiusfrees-vhm-dynastar

 

[werowance]

that's a good looking engraving. what machine did you use to do that?
I got around to doing some testing and I think something is wrong with it. on wood it goes just fine but as soon as the bit touches the copper test plate I would loose my usb connection to the laptop driving it, thus having to unplug and replug for it to find it. I'm wondering if I have some ground issue or something going on. did just fine on a test piece of oak wood that I had sanded smoothe.

here is a stock photo of the style of bits that came with mine. I hope in the next few days to get some time to check all the electrical connections and bring home a more shielded usb cable as I have heard that is an issue a lot of times

 

[joneb]

Hi Werowance My advice is practice using the machine on your scraps you are going to break cutters the ones supplied are probably not very good quality but will get you going. If you are going to engrave metal then the surface must be flat and perpendicular to your Z axis any slight deviation you will soon see in the finished product. for metal use a very light cut and high spindle speed and sufficient feed that the cutter is producing chips too fast a feed the machine will labor and chatter to slow the cutter will heat up, assuming your cutters are sharp.
If your zippo lighter has a light curve the engraving will be uneven and holding it down rigid will be a problem but the only way you will learn is to try it, don't try on anything that is valuable.
Machine rigidity is key on all the videos I've seen on your machine they use wood.
Have Fun

 

[werowance]

started playing around with the laser that came with it and some aerosol "brilliance" laser marking spray. this stuff works really good on stainless. the picture is not of the best one i did. later tries this weekend produced a much better one than the one i first took a picture of. it leaves a nice almost black mark on stainless.

 

[ddmckee54]

You said that was a spray used with a laser? Did the laser actually etch the metal because of the spray, or did the spray get vaporized and bonded on the surface of the metal?

Either way it looks pretty good in the picture.

Don

 

[werowance]

bonded. have you ever seen a yetti tumbler cup with the grey business logos and such. it sprays on like a white powder and the laser melts it. i think its a ceramic.

 

[ddmckee54]

Thanks for making that clear.

 

[Mike Henry]

There are a number of products on the market that can be used to laser mark on various metals with CO2 lasers, like the ubiquitous k40 lasers sold on Ebay and elsewhere. Some product names include Cermark, LaserBond 100, Brilliance, Enduramark and probably others. So far as I can tell these products all use some form of molybdenum in their compositions and some folks have tried moly lube or similar products, though results usually aren't as good as with other products mentioned.

I've used both LaserBond 100 and Enduramark with good results and the marking is surprisingly resistant to abrasion so it should last a long time.

mh

 

[werowance]

mine was Brilliance. I'm using a 15w I think diode laser. I had to turn the power way down seems 2-5w works well. I also did a test with yellow hot dog mustard as I saw that on the internet and it also worked "ok" on stainless but not nearly as dark as the brilliance was. but did smell like a hot dog stand after it was done lol.

I also saw regular spray paint on brass which you burn off the paint and then chemical etch or electro etch as the left over paint acts as a barrier to the etch. then when done use paint stripper to remove the rest of the paint. I did a single test run on it and it works but that was before I learned how to properly focus my laser and also control the power on it so the burn was a little over the desired mark and I did not get around to testing again.

 

[awake]

Weworance, do you happen to have a link to the 15w laser you are using? I've been considering pulling the trigger on something like that ...

 

[werowance]

it was a package deal on ebay. here is the unit I purchased. ill look at it tonight and try to get a model number from the laser itself

https://www.ebay.com/itm/174081912251

 

[awake]

Thanks!