Project Guidance, Giant Periodic Table of Elements from floor tiles

OK, I have had the machine (X-Carve 1000mm, 24v spindle) for just two days, and want to take on a pretty ambitious project. I am sorting out the work flow and tool chain and there is a lot I will have to learn, so I want to run my outline past you guys to see what you think. I am making a bunch of assumptions about things that I have NEVER done before.

Not only do I have no experience with CNC, I have none with graphic design. But I was a science and math teacher for the last ten years. In April I agreed to become a STEM/shop teacher and to re-commission a middle school shop program that has been basically dark for much of the last decade.

I agreed to take the job because they agreed to buy the X-Carve machine for the shop, and I am committed to teaching the kids to use it too. Formerly I was a carpenter and I can also read, interpret and follow most technical writing after having practiced law for a while, and I have done lots of model airplane and model railroading. I am NOT an engineer, but I think I have the chops to figure this out. If you all are willing to help.

Concept:
I thought it would be cool to create a periodic table of the elements from floor tiles and install them on the floor of a school chemistry lab. My rough plan is to use the X-Carve to create a floor tile for each element from asphalt tile by covering each tile with some sort of masking film, carving the tile and filling the engraving with epoxy or some other material dyed dark with aniline dye or some other pigment, then sanding the epoxy flush before removing the masking film.

Design and currently my biggest worry: I plan to design and draft the tiles in Inkscape. I just started learning Inkscape today. I have NO experience with graphic design software, but Inkscape seems like the only program within my budget that can create a base template that I can then quickly edit with different information for each element/tile. I know Inkscape can generate .svg files that I can import into EASEL, or can use in some other program. I also think Inkscape would be a useful program to teach to my students because it seems to have many elements found in CAD programs such as DraftSight and AutoCad, and that are useful in things like game and web design, plus the same files could be used with a laser cutter and I am imagining that down the line there might be projects that could use both fabrication techniques on the same work piece…things cut with the X-Carve and engraved with a laser.

If anyone thinks I am making a horrendous mistake with Inkscape for this purpose, please speak up. It is proving to be a lot of work to learn, and if I am wasting my time, I’d appreciate knowing that before I get too much further in, but I can’t justify the cost of Corel Draw unless there is fatal reason to avoid Inkscape.

Design Elements: The tiles will contain atomic number and mass as well as symbol and name. I am thinking about whether they should contain other information…a Bohr model might be useful for the first three periods. Lewis dot diagrams for the rest, or maybe just electron configurations in the usual form (Ar+4s2,3d10,4p1 etc.) or? Should they be in various colors to identify them by group (metals, semi-metals, noble gases, etc?) Descriptive text might be good, but hard to read if the tiles are on the floor and too much detail might make the tiles fragile in a school setting. I’m not asking the community for answers here, just sharing my thoughts, but certainly I’d listen to opinions.

Anyway, my first step is to learn Inkscape, but that’s going to take a few days. Meanwhile I am still commissioning the machine and learning my way around Easel and I will need to decide if I should use, and therefore teach 11-14 year olds to use some other program to send G-code (something else I barely comprehend) to the machine.

Still ahead: how can I engrave asphalt tiles? Tool type, speed, depth, rate etc. Building some sort of a gauge template to assure that the tiles all match and the machine always homes to the same spot on each new tile. Dust extraction…I bet ground up asphalt tile makes nasty dust. What sort of masking film? Will Epoxy be good for filling the engraving or should I use something else? What should I dye the fill with? Will the maintenance team be cooperative in helping me install it? Will my science colleagues get cold feet about having a periodic table on the floor of their classroom? Will the new principal whom I have not met yet be supportive of the project. Can I figure this out and get it done before school starts in just 26 days!..so much to learn about the machine, software, people, and chemical elements too!

The ultimate goal, of course, is not to create a periodic table from floor tiles. It is to teach kids the complete product development tool chain, from the conception stage through sketching the idea on a napkin, making drawings, determining appropriate prototyping and production techniques, manufacturing and marketing a product. The X-Carve is just one tool in the chain, but I think this is a project that will illustrate all of the tools and help me learn the ones I don’t already know.

Anyway, if anyone has thoughts, I’d sure admire to hear them.

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sounds like fun project to do :smile:I like that you taking all to kids and let them work on it.
I’m noob in all this on exact same lvl :smile:

I do concrete work (art stone, marble from concrete) I got CNC to cut design(periodic table in your case) on aluminium and make plastic mold of it for concrete.

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and here is out of form in concrete

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First off when you say “asphalt tiles” I assume you mean the Modern VCT tiles which are produced from a mixture of colored polyvinyl chloride (PVC) chips, and not the old style asphalt tiles which contained asbestos and were used predominately between the 1920s-1960s. Please tell me that is correct and you are not planning to mill asbestos tiles.

So if these are the modern tiles they should be 12x12 which is a fine size to work with on the X-Carve.

Milling the tiles will present some challenges.

  1. Securing the tile will be a bit of trouble, since just holding down the edges will not work very well since the tiles are flexible and will tend to pull up into the bit. So you will need a two sided tape under the tile to resist the upward forces and keep the tile flat against the wasteboard.

  2. The PVC will melt from the heat of the bit as it mills the material, so you will need a forced air system to clear the cut material from the tile and to cool the material.

  3. The PVC tends to tear as it is being milled, so you will need very sharp bits and very precise feed rates to minimize the tearing. Cutting nice clean lines is going to be tricky and will require a lot of experimentation.

Using Epoxy to fill the cuts should work, but the epoxy is messy to work with and moderately expensive. You will also need to be able to sand the surface of the material after the epoxy has cured. Not really sure how that will work on PVC tiles. This may be the most difficult part of the project.

Coloring the epoxy is fairly simple, I have had good results grinding up pastel chalks into a very fine powder and mixing the powder into the epoxy.

You may also have a problem with the tile flexing and the epoxy being rigid after it cures. This may cause the epoxy to become detached from the tiles.

Inkscape should work fine for the design. Then you will need another program to create the tool path and generate gcode. There are many options, but I would suggest just importing the SVG files from Inkscape into Easel to begin with.

You should also check to be sure you have room for the periodic table, if the tiles are 12x12 then you will need a space 18 feet across and 10 feet deep. More if you want a border around the table.

So it sounds like a fun and challenging project! I hope you post a lot of pictures as the project progresses. I will be very curious to see how it turns out.

I don’t even have am XCarve yet, so I’m not even a noob… but I wonder if instead of only cutting the surface of the tile and trying to fill in with epoxy, et al. Would it be better to use 2 different tile colors and inlay one into the other. I would think you could cut the tiles with a 1/16" end mill by using the cooling suggestions Allen suggests above. If you need to reduce the size, you could cut 4 elements into a single tile and end up with a 9x5 foot design. I suspect this would work better in many classrooms.

A second suggestion if you don’t have open floor space could be to mill a wall hanging instead of floor tiles.

Good luck with your efforts!
–Rick

Inkscape is definitely the right choice for this project. You’re doing a lot of text layout and placement so a CAD program like sketchup or fusion360 would be cumbersome for getting the kerning and leading right.

Allen mentioned a few problems with the tiles, sourcing the vinyl tiles instead of asphalt, cutting bits/speeds/feeds etc…

I would set up a jig on the machine to mark a 0,0 point on the machine. For instance, on my X-Carve, I have a left guide screwed into the wasteboard holes, which I’ve already squared up, so that any workpieces I put into the machine are square and aligned to the zero point every time. I also have limit/homing switches installed which (though I don’t use them electronically) gives the machine bumpers which define a repeatable 0,0 point.

There are something like 118 elements in the periodic table. Are you going to do 4-up groupings or each element on its own tile? Each tile may take about an hour to cut if you use fills, that’s a very large investment of time.

I think inkscape is a good program to be using and teaching.
It is free :wink: and many of the features and principles your students will learn can by applied to other professional software products.

Carving the tile.
You will have to play with your settings but I think maybe using the linoleum material setting in Easel would be a good place to start?
Clamping flexible materials can always be problematic. @AllenMassey is right, double sided tape is a good idea.
There is more side-to side forces than up down when carving so even if you use tape it is a good idea to have a hold down clamp on each side. Just in case.
Or, because you are going to do a lot of them, maybe making some kind of frame that goes around the whole tile instead?

Filling the tile.
That too will involve some experimentation. You could try not carving too deep and just use a bit of paint. But I am not sure how that would stand up to the floor polishers.
For questions about epoxy check out smooth-on. Even of you don’t uses their stuff they have a tone of tutorials that will be helpful. If your local smooth-on distributor is good they can also give you advise on what material will bond best to the vinyl floor tile and stand up to foot traffic.
Inlay would probably hold up the best. Cutting out the letters in a contrasting tile color. But inlay can be tricky as you have to get the inlay to be just a bit smaller than the hole to fit properly. Simply scaling the font size won’t work. You need to convert the text to curves than do a offset path of the appropriate size for each curve. Not hard once you figure it out, but it takes a bit to get a feel for it.

Color:
It looks like CVT (Commercial Vinyl Tile) comes in a tone of color options. So you should be able to source something that matches the standard table colors :wink:

Thank you all for your input. I am experiencing a very steep learning curve and apologize for not replying sooner. Still moving forward on this project, but realizing that it is a lot more work than I had initially thought. For those who suggest that woodworking with a CNC machine is cheating, I definitely disagree. More importantly though I am fully convinced that learning to use this machine is an appropriate lesson for middle school kids.

I did think that the machine would be much faster than it is, although it is much faster than 3d printing, which is what my bosses were pushing for instead of a CNC machine. I do think I made the right choice.

Based on the input I have here, I am modifying the project. The floor tiles in my school are 9" and I had planned to use modern VCT, not asbestos. However, the EXISTING tiles most likely are asbestos, making the idea of pulling up old tiles and replacing them with new ones to make the periodic table a non starter. But, I think I may be able to interest a local charity, or a local laboratory in hosting the installation instead, and that might be a better experience both for my students and for the benefit of the future of my program. One bridge at a time however.

For the moment I am flailing around with Inkscape, experiencing a much more painful learning curve than I had expected. Usually I pick up software pretty fast, but my lack of familiarity with CAD and computer graphics is kicking me in the tail, and I have not yet succeeded in creating anything in Inkscape that I can recognizably open in Easel. Still, it is good for teachers to run into things that are hard to learn. Makes us much better at helping kids through the things they are struggling with. Besides, I bet they will figure out the whole tool chain much faster than I do.

Thank you, that looks really nice. Am I understanding correctly that you used CNC to make an aluminum pattern which you then used to make a plastic mold to form the concrete?

yep thats what we do.
but you can make simple form box out of wood and place mirrored engraved plastic on bottom and pour in cement(or tile mix or sculpture mix,…) it will work more like stamping the concrete and plastic gives glossy face

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I found this tutorial to be a good introduction to cad/cnc etc. with Inkscape: https://www.youtube.com/watch?v=GuvvO6TELt0

I don’t know for sure, but reflooring over the existing floor, without tear out, might be an option.

Another good flooring or tile material might also be cork.

Jerimiah, Thank you for the referral to Christopher Robinson’s tutorial on Inkscape.

Allen Massey, Thank you for the comments on clamping down the material and all of your comments in general. Extremely helpful. The table will fit in the room I had planned, but asbestos concerns do present a problem. I’ve got a box of VCT though for experimentation.

RickSchmalsried, the wall hanging may be a good alternative, and I could do that with different species of wood, or possibly in layered acrylic instead of tile.

Mike, thank you for your additional thoughts on clamping. Having played with the machine a bit for the past few days, the idea of setting up fences along the x and y axes makes lots of sense especially as kids will be using the machine.

AaronMatthews, I like your suggestion of a frame to completely surround the material so that home settings are easily repeatable. Taking it one step further, I could make an auxialliary waste board of Masonite that had fences built in to hold various different “standard sizes” of material. These would bolt into the holes on the standard wasteboard and protect it from the inevitable altercations with the mill.

I’m pretty rapidly reaching understanding on the mechanical aspects of this project. Things like feed rates, depth of cut, tool choice and so on seem to make sense very quickly. Where I am really struggling is on the software side, and understanding how to send the design in the drawing program to the machine. I’m doing reasonably well at making simple designs IN the Easel application, but I am not so successful at figuring out how to tell Easel to identify tool paths.

For example, If I create the letter “K” (Potassium) and want it to be raised in relief, I can’t figure out how to cut out (I think the term is “pocket”) the material between the outline of the letter, and a raised “border” around the perimeter of the tile. So far, I have managed to get the machine to carve an outline around the letter “K”, but then when it finishes the outline, it begins to “fill” the area inside the border, and in the process, carve away the letter as well.

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this will help you

In Easel create a square that is the inner dimensions of the “border” and center it. Then send it back (in the edit menu). Then make the K and the border and whatever else you want to be raised all set to 0 depth (white). Set the square you created to the depth you wnant to cut. See the tool paths then.

This is similar to what I did here: https://www.inventables.com/projects/mustache-inlay-coasters

Archil and Sketch, thank you both for the links. I continue to work my way through this and am working on building curriculum so that students will be able to work through it too.

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