The last few months, I’ve been designing, 3D printing and giving away door signs to friends and family. I’d like to share some of them.
It started when I made one for myself and my wife:
This was made using a plastic filament containing 35% real powdered wood. There are some really cool things you can do with this; sanding, drilling and staining will work with about the same properties as real wood. Since wood will change color when getting closer to burning temperature, I was able to develop a method for simulating natural wood grain – by randomly changing the temperature between the individual print layers, spanning a total range of about 30 degrees (C). This had to be done in waves, so that there would not be more than a 3 degree difference between two intermediate layers; If the printer is not able to get close to the target temperature within a certain time, a security feature in the printer firmware can abort the print and shut down the printer. This is because a large temperature difference between the measured and target temperatures could indicate that either the heater element or the thermistor have come loose; the automatic shutdown kicks in to prevent potential fire hazards.
The printout took about 40 hours, but in hindsight I wish that I would printed it even slower. Printing too fast often causes ghost effects around details, called “ringing”. This happens when the print head makes a sudden direction change and the inertia of the head causes vibrations that show up in the print. Unfortunately, I was not able to get rid of these effects even with sanding from 120 up to 800 grit sand paper. Aside from sanding, I enhanced the letter details with scalpel, dentist’s tools and small diamond files. But I wanted to accentuate the letters even more, and went with a few layers of dark mahogany wood stain. After drying, I sanded the entire sign again to remove the staining on everything but the debossed letters. Lastly, I finished the sign off with two layers of polyurethane to give it some surface protection and a glossy finish. I was worried that this would take away from the wood look, but it turned out pretty good. Perhaps a bit to much yellow, but good enough for an apartment door.
Next was a door sign for our friends who just got engaged. This was still being printed while they were visiting, so I didn’t have time to do a photo shoot before they brought it home – hence the CAD rendering. The outermost frame was based on a free vector graphic that I found here, but I had to remake it quite a bit to make it work.
After that, I designed a couple of things for my brother. He collects and restores vintage drums, so I made a sign for his workshop along with a personalized, fully functioning drum tuning key. I tried to make the font as close as possible to the one in his favorite drum brand, DW Drums.
Finally, a door sign for the his family. The metal corners were fastened them by pushing the nails in using a wood burning iron. The iron heated up the nails, the nails melted the surrounding plastic, and when cooled the plastic solidified around the nails. I opted on only using nails on the short side of the metal brackets to avoid having to cut them down from the back side.
I used the same type of corners on a door sign to my sister-in-law, who also got engaged recently. This time I went larger, and played around with putting part of the text outside of the rectangular base shape. I also made the sign thicker and integrated four magnets directly into the backside of the sign, so that it can be easily fastened on their (steel) apartment door. Or the fridge, if they prefer. I used the same method to fasten the corners as before, but this time cut the nails in half and inserted them from the front of the sign.
I’ve done a number of other signs as well, but those have mostly been variants of the ones shown in this post. These are the essentials from the last