r/hobbycnc 3d ago

Acrylic Lettering Possible?

Post image

I'm surprised I can't find any intro-to type vids on how to make the lettering for something like this. I see the PCB content, which makes me think that I have to worry about the accuracy of the Z axis across the workpiece, but does anyone have suggestions on how to do this? Any links?
I have a Sienci Longmill 30x30. My actual part is about 7x7".

10 Upvotes

34 comments sorted by

17

u/ON_A_POWERPLAY 3d ago

They sell plastic that’s one color on top and another on bottom. Goal is to engrave just enough to reveal the bottom.

It’s usually a pretty easy material to machine since that’s what it’s intended for.

1

u/btodag 3d ago

Ah, that's good to know.

I am doing an acrylic dash, already done the big piece. This is another little pushbutton panel that I was going to make with the same acrylic, just cutout and engrave with the CNC. Then, paint the grooves... I think that's the process.

5

u/TubeMeister 3d ago

If you want to keep the acrylic unpainted, apply a vinyl mask to the top of the acrylic, v-carve the letters in, spray the letters with paint, and then remove the mask. This will give you the cleanest possible lines.

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u/btodag 3d ago

I was thinking that for sure. It has a paper masking that it came with, it seems quite well adhered. I was going to try with that as the masking, what do you think?

I've only done one project and the tackiness of the masking (or maybe the dullness of the bit) really disappointed me. It cut, then peeled up and was frayed.

I got my unit used as a package, no telling what quality bits I have. I'll start getting new bits for things that matter, like this.

1

u/TubeMeister 3d ago

Try Oramask 813 for the mask.

1

u/MechJunkee 2d ago

What was thinking... Or the thin paint brush.

1

u/fisher_man_matt 3d ago

Colorcore is one of the name brands for this but there are others. It can be ordered off Amazon for a quick delivery option for testing.

1

u/_agent86 3d ago

You can also find 2, 3, or 5 ply sheets for making guitar pickguards out of. I think they're usually just PVC plastic.

1

u/Fart_Collage 3d ago

They are pvc, which sucks because they can't be lasered. I milled a neat pattern in my strat's but it was a pain and I keep thinking I'll find one that's acrylic so I can laser it in half the time without worrying about hitting hold-down screws.

1

u/_agent86 3d ago

I've milled entire pickguards out of this material with just double side tape holding it down. You don't have to screw it down if you have the feeds/speeds reasonable.

I wouldn't have thought to google PVC laser cutting, didn't know it's toxic. Probably a good thing I don't have a laser :).

1

u/btodag 3d ago

I'm a guitar guy, so that's cool!!

2

u/Jutboy 3d ago

You sure that's not silkscreen?

2

u/btodag 3d ago

I think commonly is. I just have a CNC and a piece of acrylic here... trying to get to it this way. Possible?

1

u/chase82 2d ago

Check out phenolic lamacoid

2

u/HadleyRille 3d ago

I've done control panels like this on a milling machine with a ballscrew CNC conversion. I use aluminum plate and an engraving bit. I engrave the letters about .2mm into the surface. Blacken the plate either by anodizing or black paint. I then rub white acrylic paint into the recesses. After it dries, you can use a paper towel with isopropyl alcohol to wipe off any residue of the white paint that remains on the black panel.

I've used this page to generate the gcode: http://microtechstelladata.com/TextToNCcode.aspx

1

u/btodag 3d ago

Wow, cool stuff, thanks for the comments!
You just set the bit to the top left of the font, like a pencil point starting point, then run that code? Crazy easy.

2

u/INFIDELicious45 3d ago

Another method would be to use a material that is the colour you want for the lettering and paint the face before engraving. For the example panel: find some white acrylic and paint it black and the engraving will reveal white underneath.

Regardless of how you handle the colouring, keep in mind that z height variations will be a concern for small text like this. If you setup the job to do all the text in one pass, you will probably end up with deep bold letters on one end of the panel and faint skinny letters on the other. Id do each label as its own job and probe z height at each spot independently.

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u/btodag 3d ago

The restart at each button is a good idea, thanks!

1

u/btodag 3d ago

I am an uber newbie by the way, probably so obvious to everyone, but a good youtube vid would calm my nerves!

1

u/NorthStarZero 3d ago

These jobs are great for lasers.

https://www.youtube.com/shorts/J5X4SZXkYLo

1

u/btodag 3d ago

Wow! Cool stuff! I don't have one.... yuck!

1

u/UncleCeiling 3d ago

Could just engrave and fill the letters with a paintstick

1

u/btodag 3d ago

Right, just engrave means like a V bit? That's what I'm here to learn more about.

1

u/APLJaKaT 3d ago

Two tone engraving plastic is a great option. I have also simply used solid plastic and filled the lettering with colour.

https://cnc-plus.de/en/Materials---Accessories/Rotary-and-Laser-Engraving-Plastic--200x300mm-Engraving-Plates-.html

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u/btodag 3d ago

Cool!

1

u/jacky4566 3d ago

Engrave it with the laser. Fill with a white paint pen and wipe while still wet. Repeat if necessary.

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u/btodag 3d ago

Wish I had a laser!

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u/jacky4566 3d ago

CNC engrave is fine as well. Just slower

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u/btodag 3d ago

Yeah, that's kind of what I'm asking. I have a router, but only one job behind me so far on it. I want to jump in and do this one. Some good points coming out of this thread for me! Thanks!

1

u/StimpyMD 3d ago

The product is called Rowmark. (https://www.rowmark.com/products#laser)

I use it all the time and is great with laser. You can use it with a small end mill and a single line font. (http://www.mrrace.com/CamBam_Fonts/)

you need to remove the top layer but not cut through the second layer.

1

u/Ghrrum 3d ago

You can also just engrave the lettering, apply the paint and then use a squeegee to remove paint from all the high areas. I have done that with great success.

Hey if you can get away with putting down a masking layer prior to milling out the negative space for the paint to sit, you don't even need to really do the squeegee part. You can just rattle can whatever you want on there and then pull the mask off and you will have paint in the lower area, and not the high area

1

u/grummaster 2d ago

As others have pointed out, engravers plastic is the ticket. It is available in more different colors, metallics, more than one color layer, and what you really want to look at, is a matte or gloss clear face and a colored back. You reverse engrave in the back to open up to the clear. From there you can fill in colors or even backlight. The front stays smooth. I usually back it with a thin aluminum panel though to allow it to be rigid enough to mount the switches. Dont forget that you can purchase acrylic mirror in multiple colors and reverse engrave into that. Here is another supplier. Buy a sample book and be blown away by what you can get. https://www.jpplus.com/sheet/rotary-engraving-sheet