shady_gawad http://www.robotdigg.com/product/530/Rostock-steel-ball-head-screw
actually sorry they came from the link above.
shady_gawad@Mshievitz You are probably right, the ball to ball distance is 60mm ( I called it "arm distance". The balls I used are from aliexpress I'll find the ref for you.
The IR board I used is from David Crooker aka DC42: all the details are here: https://github.com/dc42/OrmerodSensorBoard
shady_gawad@Mshievitz If you are intersted I'll take the time to draw the modifications for the BL-touch over x-mas
shady_gawad@Mshievitz I just checked and it wouldn't be too difficult to add the BL-touch. You might not have noticed but the fans I use are actually radial fans. (the smallest ones available) I found and they provide more than enough airflow for PLA where it's the most important. I have 2 of them mounted at 120° angle
https://www.activa.com.tw/en_product_page.php?id=708&type=40