I have built an MPCNC and it’s ease of use and accuracy amazes me. I was wondering if anyone if anyone has tried to engrave glass with a carbide bit. I only want to graze the surface with my wife’s signature to mark her glass designs. I was about to give it a try, but I thought maybe someone else has already done so.
What about cutting a vinyl stencil and using glass etching?
I’m familiar with engraving by hand on glass with a dremel. I’d assume that you would need to either mount the engraver side or the workpiece on something with that would give in. For example on some sponges or soft foam?
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The EvilMadScientist EggBot supports a vibrating diamond engraving tool option. Doesn’t look too complicated to replicate, depending on what’s in your parts drawer.
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Thank you for the suggestion. I knew there must be a way.
Thank you for the ideas. I had not thought of the acid etch method.
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Acid etch and vinyl cutter tutorial here:
https://docs.v1engineering.com/tools/drag-knife/
There is also a page on etching the back of a mirror with a laser (doesn’t work on regular glass):
https://docs.v1engineering.com/tools/laser-engraving-mirrors/
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Thank you very much. I knew with all the knowledge of others, I should not just jump in and ram a carbide drill bit into glass without asking for some help. The acid etch and vinyl cutter is just what I need. I am truly appreciative of your advice, and have downloaded the holder files. Onward and upward.
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I did some research into engraving glass. Most of the pages lead me to this company’s tools. From what I could tell, results were excellent. At $180, the tool was more than I was willing to spend just to satisfy my curiosity, but someday, when I have a firm project in mind, I’ll splurge.
Not about glass specifically but fits what you’re doing: Is there a stylus available that would plug in like a mouse and allow you to digitize things like signatures by writing them in something like Paint? And to go a little further, software that would smooth out the curves of hand-drawn sketches?
There are wacom tablets that artists use to do digital drawings with a pen. Wacom is the only brand I know of, but I am sure there are others. It is also possible to scan in a drawing and end up with a high contrast image. Then you can use inkscape to trace the shape and make an svg. But most likely, you will want to learn a little bit of editing in inkscape to clean it up, or maybe even just trace a single line inside the scanned image to make a single line path.
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Thanks! I was just curious, I’ve tried doing a signature with a mouse and thought it’d be neat if I had something that functioned like a mouse but fit your hand like a pen.
I did some CNC wood cards (anniversary and Mother’s day) last year and wanted to sign the card. I singed a piece of paper, scanned the result into my computer, and used that paper as a “canvas” in Fusion 360. I then used spline tool in Fusion to trace over the signature. The resulting path was then carved using the Trace toolpath. I was very happy with the result. The signature was smooth, consistent, and really looked like my signature.
A similar process could be done in other vector-based programs. I’m sure it can be done in Inkscape.
While the results won’t be as smooth, the trace bitmap can be used in Inkscape to create curves that can be engraved.
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I may be missing something here, probably because I have yet to make friends with Fusion or Inkscape, but wouldn’t I arrive at the same place by signing a piece of paper, taking a digital pic, saving it as a .jpeg and loading that into Estlcam and cutting it?
I don’t use Estlcam, so I cannot say anything about the results. The process I described produces a spline that can be traced by the CNC. I expect that anything Estlcam produces will more like the Trace Bitmap in Inscape where you get shapes that can be engraved but those shapes might no have smooth edges.
Sounds like my handwriting. 
So when you use the spline tool I’m guessing it produces a line of consistent width that can be engraved as a single line? I guess I’m getting into one of those areas that seems so natural to the human mind but isn’t so natural at all to a computer?
I know the latest version of Inkscape makes that easy. It also has a feature that I just learned about today. Under Extensions select “Render” then select “Hershey Text”. You will get a pop up window that asks for your “TEXT”, “WHAT ACTION TO TAKE”, which will be “Typeset that text” and lastly, choose a font. I click “Live Preview” and then “APPLY”. What Hershey text outputs is text composed of one single line characters that can be engraved without the overlap of other text that is composed of two lines. This makes it very easy for engraving text into your work. Just select “Center” if you are using Estlcam and it does renders it perfectly. I do not know about other programs, I cannot afford them.
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Loading it as jpeg will make estlcam make a mark for each dot. It isn’t useful for a signature. The jpeg is just a big bucket of pixels, you really want a shape, which you would get from an svg or from a dxf or a spline in fusion.
Thanks for that! I have to work at it but know I still hit those snags of not understanding why I can’t make the computer understand what seems such a simple idea to me. I’m getting better at it but still have to remind myself it does what I tell it to do and not what I think I told it to do.
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So when you use the spline tool I’m guessing it produces a line of consistent width that can be engraved as a single line?
In any vector-based program, a spline tool produces a curvy line like a line tool produces a straight line. Many/most programs treat splines as have zero width. If one or more splines enclose an area, you get a shape/object/profile. Generally, if you import a DFX or SVG into a program, you are importing shapes defined by splines.
So a spline is a general tool that differs based on what toolpath you select for your milling. If the spline encloses a shape, then you can pocket out that shape using your CNC. But you can also create a toolpath that walks the spline. In Fusion 360 that toolpath is called “Trace.” If you are using a chamfer bit, then you can select the width of the line by selecting how deep the chamfer bit cuts. If you are using a straight endmill, then the width of the line will be the width of the bit.
Sidebar: There are multiple kinds of splines using different math/algorithms. And there are multiple ways to control the shape of a spline. Mostly I see what Fusion 360 calls “Fit Point Splines,” where the spline passes through points the user specifies, and the curve is controlled by handles at each point. Programs used to create drawings (rather than CAD programs) might combine the concept of spline, line width, and line color into a single concept.
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Thank you Donald for this pointer. I spend a bit of time with Hershey Text this morning, and this is what I found:
- In the latest version of Inkscape, it is installed at Extensions/Text.
- It provides a limited number of stick fonts rendered using line drawing like would be required for a plotter, or as related to this topic, engraving tool.
- There is a least one place that sells additional fonts for this extension.
- The fonts use noticeable line segments for curves. These segments are not optimal for engraving or pen plotting, but they can be simplified and turned into curves using Inkscape’s Path/Simplify tool. And the paths/splines used for the letters can be directly edited to further improve the writing.
- The SVG output by Inkscape come in cleanly into Fusion 360.
- Creating the Trace toolpath from the splines and lines requires selecting all the individual segments of each letter in order. The number of segments is reduced if the path is simplified in Inkscape. This is cumbersome, but very doable for shorter lengths of text. I wouldn’t want to do paragraphs, but individual lines are fine.
So thanks for another addition to my toolchest.
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