ToolsToday.com and Glass Impressions have partnered up to bring a fun holiday CNC project. Today we are going to make aluminum snowflakes with the CNC router.
I started with a 24″ x 24″ section of 3/16″ aluminum sheet material and used a random orbit sander with 150 grit sandpaper to clean up the surface and get it ready for paint. I used a vacuum and a brush attachment to remove as much aluminum dust as possible. To removed the remaining dust, I used tack cloth.
Once the dust was removed, I used special aluminum spray paint primer and then sprayed 3 different colors on top: green, red, and gold. It is important to use multiple light coats rather than 1 or 2 large coats. This spray had a tendency to blotch and run.
As the top coats dries, I loaded them into the CNC and used aluminum clamps on the edges to hold them down. I used Vectric Vcarve Pro to design the snowflakes and program the tool paths. I used a more aggressive feed rate as I can use the FRO (feed rate override) in the CNC Shark Control panel to slow it down. That way I could always have the option to fine tune the speed and feeds. If I set the feed rate to a conservative number, I wouldn’t have the option to speed it up unless I went back to the tool paths and redid the entire program.
I started with a 60 degree V-Bit from Toolstoday.com. It was Amana Tool # RCK-380 with insert RC-1075.
Speeds and Feeds:
- Feed Rate: 5 inches/minute
- Speed: 24,000 RPMs
- Chip Load Per Tooth: 0.0002″
- Step Down per Pass: 0.0313″
As the engraving tool mills the paint away, the shiny aluminum shows through. It provides a nice contrast to easily read the text on the snowflake.
After the engraving tool path was completed, I swapped out the bit to a 1/4″ Solid Carbide Spiral “O” Flute Aluminum CNC Bit. Amana Tool #51402.
Speeds and Feeds:
- Feed Rate: 20 inches/minute
- Speed: 10,000 RPMs
- Chip Load Per Tooth: 0.002″
- Step Down per Pass: 0.0625″
This speed and feed combination produced a beautiful chip and holy buckets they would fly all the way across the shop. I always find filming CNC projects very messy as my dust boot would provide a very boring video. I am working on a design to where the dust boot can be attached from the side rather than over the bit and up from the bottom.
During the first sheet (green), some minor vibration was occurring. Just to experience and gain more knowledge techniques for future projects I modified my holding methods. In the .75″ perimeter of the sheet (red) I drilled 8 holes to secure a pan head screw and a washer to obtain a very rigid holding setup. After I ran the engraving process, I used the V-Bit to mark in between the snowflakes where I can drill and apply additional screws to the middle of the sheet. This is where the vibration was occurring.
I then installed the 1/4″ aluminum bit again and went to town!
Once the milling was completed, I brought it over to the drill press and drilled a small hole for a ribbon. I made sure to countersink the hole so the ribbon would not rip.
Big thanks to ToolsToday.com for sponsoring this video!