Can you develop variable intra-layer speeds that depend on the degree of overhang? What follows are three pictures that show how slowing down the print speed on overhangs up to 57 degrees can create nice smooth surface finishes without the need for support. In fact adding support to the slowest speed print of these examples appears to make the surface finish worse, not better. I have not experimented w/ overhangs > 57 degrees yet so I don't know if there is an overhang degree limit where support will give a better finish vs no support at slow speeds:
At perimeter print speed 30 and overhang 57 degress the surface finish over a large area is rough and wavy (area circled in red):
- Perimeter Print Speed 30 - No Support
- KISS Perimeter Print Speed 30 - No Support - Markup.jpg (44.43 KiB) Viewed 7895 times
- Perimeter Print Speed 15 - No Support
- Perimeter Print Speed 15 - No Support - Markup.jpg (41.58 KiB) Viewed 7895 times
- Perimeter Print Speed 5 - No Suport
- Perimeter Print Speed 5 - No Support.jpg (39.01 KiB) Viewed 7895 times
Printing w/ support and all print moves at speed 30 mm / sec the whole print takes 6 hours 29 minutes; however printing w/ support still gave a rough surface finish.
Printing w/out support and printing the perimeter at 5 mm / sec and loops at 15 mm / sec gave me a nice surface finish w/ only minor blemish, but the print took 9 hours 1 minute. If you could create a variable layer speed that for example would print at 30 mm on the non-overhang section of the layer and slow down a % based on the degree of overhang it encounters, that would greatly reduce print time and at the same time help give an awesome surface finish on prints w/ overhangs.
Something like variable intra-layer speeds might also come in handy for the Coast feature you are looking at creating.
Edit: Perhaps in the first step towards implementation you could have two sets of print speeds. One set of print speeds for layers where the overhang is < than the support threshold (in the Support tab) and a second set of print speeds for when the layer contains an overhang(s) >= the support threshold. That way at least layers that have minimum overhangs can be set to print faster and layers with larger overhangs (for example > 45 degrees) can be set to print appropriately slow to improve the overhang area print quality.
