Scoliometer for the scoliosis

thingiverse

This is a 3D printed Scoliometer designed specifically for recreational use only. The model should not be relied upon for any medical conditions due to its inaccuracy. The scoliometer's design concept is straightforward and cost-effective, allowing it to be easily produced and printed. My son's scoliosis does not require precise monitoring with this device. Given the scoliometer's price, I created a proof of concept to potentially use later if needed. To compare different materials, I tested a cheap plastic 6mm BB pellet and a free 1/4"(6.3mm) bearing ball obtained from a local bike shop. Two tracks were added to the scoliometer: an upper track with a 30° angle and a lower track with a 15° angle, marked every 5°. The print time was approximately 10 hours when using a 0.2mm layer height. The cheap BB pellet proved unsuitable due to its irregular shape and insufficient weight. However, the 1/4" ball bearing might be sufficient for the upper 30° track but not ideal for the lower 15° track. To achieve better results, larger balls should be used; a suitable example can be found at https://youtu.be/caBzi1Imd7U. There are two methods to insert the balls into the scoliometer: either during printing or after completion by cutting a slit and pushing them in. The narrow side wall, printed with a single layer, is easily accessible for cutting a line to facilitate ball insertion. If the balls become stuck on the track, a gentle tap with the finger will dislodge them. A larger ball provides more surface area to overcome layer differences and rolls more smoothly due to its increased weight. Several improvements can be made to enhance the scoliometer's performance: 1. Utilize larger balls, up to 7.5mm in diameter with the current design. 2. Print with a smaller layer height, such as 0.10mm for a smoother track (approximately 20 hours of print time). 3. Apply acetone vapor to smooth out the ABS track. 4. Use spray paint or epoxy to smooth out the layers within the track. 5. Insert a vinyl tube as the track. 6. Scale up the scoliometer in slicer software and use even larger balls, such as an 8mm ball scaled ~7% bigger; this may exceed some printers' Z height limits.