3D Print Custom Arch Supports

Most of the world uses footwear to protect their feet from the elements, provide some comfort when on the move, and as fashion for many. But what happens over time when someone wears a shoe that isn't healthy for their foot? They start to change the amount of pressure in different areas of the foot and their feet and joints try to compensate for the redistribution of pressures on the feet which can cause problems later on.

All my life, I've hated wearing shoes. The cookie cutter styles either would either squish my feet, not provide the right support leading them to be uncomfortable (causes foot or back pain) or just wear out too quick. As a result, I've preferred to wear flip flops or just go barefoot when I could.

But now that I own 3d printers, I am able to correct what makes most shoes uncomfortable to wear for extended periods of time without breaking the bank.

***Disclaimer: No material contained within this tutorial is intended to be a substitute for professional medical advice, diagnosis, or treatment.***

• A soft clay or play dough.
• A cutting tool for the clay/dough such as a butter knife
• 3d printer with a build volume with large enough dimensions to print your foot size.
• TPU filament
• A 3d modeling program
• Paper and a pencil
• Calipers
• Paper scanner
• Scissors

Before I began, I did some research into foot alignment and potential causes of my lower back pain. By using a washable paint and stepping on paper, I came to understand that I have low arches/almost flat feet. As I have always had wide feet, this explains my tendency to go for shoe brands built with sturdy materials and made to be roomy such as Doc Martens.

This also showcases a "why" to my cushion based shoes wearing out a little quicker in the arch and heel areas and my dislike to wearing running shoes.

In the past, I've tried numerous insoles and retail arch supports. But due to those being "cookie cutter" styles, they were always uncomfortable in some way. I could pay a $100+ to have custom supports made, but with some TPU filament and ingenuity, I knew I could make my own for far less.

1: For making arch impressions, I used some sculpey clay from Walmart left over from a previous project. Taking enough to make about an 3inch ball, place the ball on a hard surface. Align the ball under the arch of the foot and step down. Stand straight for a few seconds and allow our body weight to distribute the clay/dough outwards and further under your foot.

2: Using a cutting tool, remove extra clay/dough. Mold outer clay to the inside foot as needed.

3: Repeat steps 1 & 2 until you have an arch impression comfortable to stand on.

Once you have comfortable clay/dough impressions, take measurements with a calipers. If you are fortunate to have a 3d scanner, you can try to scan the results. For knowing alignment placement, trace your feet and where the impressions are under your foot and scan the tracings for reference use in a 3d program.

In your 3d program of choice, create a 1mm thick tracing of your feet. I recommend adding extra length to the toe areas to compensate for different shoe lengths that can be trimmed later if needed. With the measurements of the impressions, create the arch supports and apply to the 1mm thick models. If you can in your program of choice, add a fillet/chamber to where the arch meets insole.

Unless you are looking to cast your design in another material, I recommend printing with a TPU filament as it is a flexible material that should be comfortable to wear. For arch supports, this will have enough support for the wearer, but enough elasticity to not cause any accidental damage to the foot with long term wearing. For this project I used a Sainsmart brand.

For those unfamiliar with printing in TPU, for best success it is recommended to print slow. Infill settings may differ based on wearer's preference in how rigid they want the arch support to be. Lower infills will result in a more flexible but less supportive arch.

My Print Settings:

Print Temp: 220C

Layer Height: 0.3mm

Infill: 50%

Internal Pattern: Honeycomb

Default Print speed: 20 mm/s

Supports: No

Rafts: No

When you have your 3d printed arch supports, trim as needed to fit within your shoes with a scissors.

After two weeks of wearing the custom 3d print insoles, the insoles I made are still comfortable to wear and I have had no back or foot pain while wearing my shoes for 8+ hours. Out of curiosity I took another paint on paper impression. The most recent showed my feet have more visible arches.