LESSON 3.4 · 2:08 · CHAPTER 3 · THE BEAD
Starts thin, stops fat, the seam walks
Lag at every start and stop leaves a thin start, a fat stop and a defect stacked up the part where the layers begin and end: the seam.
Predict · at 0:32 in the video
The flow lags by 0.08 seconds, and the head moves at 200 millimetres a second. How far does it travel before the flow reaches 95 percent?
About 48 millimetres. A lag gets to 95 percent after three time constants. Three times 0.08 is 0.24 seconds.
Further reading
This course is our own. These books go deeper.
- The economics of Big Area Additive Manufacturing, Post et al., Solid Freeform Fabrication Symposium, 2016
- Additively manufactured carbon fibre-reinforced composites: state of the art and perspective, van de Werken et al., Composites Part A, 2020
About the numbers
Simulations in this lesson are our own. Where a number rests on an assumption or a single source, the video marks it with an asterisk and says where it comes from.
Up next · 4.1 · 2:04Every layer has a deadline