First time with diamond drag bit

This is my first effort with a diamond drag bit on some granite tile from the home depot.

I posted it over in the Shapeoko facebook group and forgot to post it here. I am pretty pleased with it, but the SVG could really use some cleanup before I run it again. It would also be great to find a solid black tile, but as I have recently learned, a diamond drag bit does exactly squat to glazed ceramic tile. Live and learn.

Going to play with some slate next.

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That looks great! I’ve done a few things with my DDE bit, but nothing I’m willing to post yet. . .

What did you use to generate the gcode?

The original design is from a Doctor Who coloring book. I took a picture and imported it into Inkscape. I then used the trace feature and turned it into a set of paths. Export to SVG and presto. From there it was just Carbide Create for some final cleanup and into Carbide Motion.

I love using mine. I found as well that ceramic doesn’t work. I have done glass, aluminum, and granite. Looks good. I did these for a friend that wanted some jumbo coasters for an outdoor patio table.



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Have you been doing multiple passes on yours? I am curious how many. or is it just thicker lines with a stepover?

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I have had DDE bits for over a year now, but finally got around to using them.

And on that note, I just finished cutting a test piece to find out what settings are needed to get 3-4 different levels of shading like a “grayscale” image instead of having to engrave just “Black and White” images.

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I could explain it, but I think MadHatter did a bang up job with his post.

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did you coat your tiles with something?

No. That is just a $3.00 “Absolute Black” granite floor tile. They were on sale because they have two polished edges and they aren’t selling well, so I got a deal on them.

It is a 90deg bit from http://benchtopprecision.com/ in my router (turned off). and a 0.10in plunge depth.

I just engrave it and wash it off and let it dry.

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I just bought the Makita wet tile polisher to do the edges, and with two already done, I am half way there. I plan on putting white marble 2" hexagons under it for feet, with a 1.5" neoprene foam pad under that for a nice trivet for the kitchen. We have had a similar one right next to the stove made of blue granite for ~8 years, so I am sure these will hold up fine.

Do you have to use Vcarve or Aspire for this or could it be done in CC?

Also, which particular bits work? I am interested in trying it, but would like to keep startup costs low (below $50?)

I am using Vectric V-Carve desktop, but I am sure there are other programs to generate the different paths for diamond drag engraving (DDE).

I do not use CC, so I cannot comment on it. I started using Inkscape and Makercam since everything I am doing is 2D, and now I am so comfortable with that process, I am hesitant to find something new.

With V-Carve, I still do all my 2D design in Inkscape, and then import the SVG file into V-Carve to generate the tool paths.

I figure one day I will learn how to use V-Carve properly and fully, but that day is not today.

Regarding the DDE bit, I believe the one from benchtopprecison.com is the least expensive one I have seen online. The WidgetWorks one is 3x as much. I have the one from benchtopprecision and I really like it.

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I have done it in CC. Certainly a little easier in VCarve, but CC will do it too. Here’s a flag I did:

You basically treat it as a very small end mill. Settings are posted in that post. My drag bit was $50 off eBay.

Dan

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Good Evening @madhatter what program do you use to generate your toolpath? if it is Fusion360 would you mind sharing the file?

Love your work !

speak soon i am sure

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I use Inkscape to turn the logos into vector files, then I use Vectric V-Carve (Desktop) for creating the G-code.

EDIT: Also, www.benchtopprecision.com is kaput! Homann Designs has the same diamond drag engraver though.

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Well, I ordered a diamond drag bit, and I picked up some black granite floor tiles yesterday. All I have left is figuring out what on earth I’m doing, eh? :laughing:

I’ve got my artwork into a nice SVG, as I’m doing a laser engrave on some bamboo cutting boards. I did all the toolpath work on that in LightBurn, which makes it really easy to define fills (line or crosshatch). Now, I just have to do the analogous thing for a diamond drag bit. Carbide Create doesn’t let you define fills like that, so it’s out. Vectric V-Carve would send the project way over budget. It’s possible to bodge virtually anything with enough work in Fusion 360, but that doesn’t seem the most effective approach (and I don’t have enough time left before Sunday).

So, looks like my options are either settle for whatever fill I can get out of Carbide Create (although it will not please my artistic sensibilities) or splurge on V-Carve (although it will not please my budget)… or…

If I use LightBurn to generate “laser” G-code (no overscan, 2D), then convert the “dark” (S0) moves to “raise the spindle, move, lower the spindle”, that seems like it should get me just what I’m looking for. I’ll just have to run one little regex (match: “^G1(.*)S0$”, replace with: “G0Z5\r\nG0\1\r\nG1Z-5F750”) and do a quick hand edit of the beginning and end of the file to get things ready.

Well, tonight’s laserin’ time, but I think I’ve got a plan that may be up to scratch for diamond drag bit engraving. (Looking through threads, it looks like starting numbers that should work are around ~2.5mm spring compression, 750mm/min plunge, 2500mm/min feed, and a spritz of water.)

On further review, two regex replacements (and then fix just the header):

  • Search: ^G0(.*)$
    Replace: G0Z5\r\nG0\1\r\nG1Z-5F750
  • Search: ^G1(.*)S0$
    Replace: G0Z5\r\nG0\1\r\nG1Z-5F750
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@ClayJar Have you played at all with Carbide Create’s texture tool paths? I think they will do what you are looking for.

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The Carbide Create texture toolpaths are as close as Carbide Create can get to what I want, but they don’t quite get there. They do let you set an angle, and you can get the right depth. They don’t let you do a uniform fill that covers 100% of the shape. I imagine you can probably get acceptable results from them, but you can’t quite get all the way.

I imagine many people would be quite happy with the results, but since I’m completely at home throwing regular expressions around to munge exactly what I want into G-code… (Programmers have the strangest concepts on “fun”, eh?)

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I think you are on it with just replacing the laser on / laser off with Z-Down and Z-Up. You’ll lose the ability to change the line thickness (from the variable laser power) but with as many hatching and cross-hatching combinations, you’ll still be able to get a lot of different fill densities and patterns.

Can’t wait to see how things turn out.

I did it in CC by creating a tool with a small tip, then cutting filled areas as pockets. It’s not super artsy, but it works. VCarve will definitely do it with a “quick engrave” tool path, and what you’re doing with Lightburn sounds like it’ll work too (just a little more handiwork and a lot less cost). Pretty cool stuff!!!

Dan

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