1st layer print issues from cold
I raised this issues when I first got my printer a year ago and didn't really get a response that worked. So since then I've been working around the problem. Thought it might be useful to resurrect the question to see if anybody has found a solution or any new advice.
Basically the problem I have is a printing from cold (printer off for a while so fully cooled down) vs. printing from warm (cooled down enough to get print off then print again) is wildly different. The two prints below are using exactly the same settings (z adjust etc...) the one on the left is printed from cold with the printer left off overnight. The one on the right is printed immediately after once the bed has cooled enough to get the print off safely so 30 degrees or so. As you can see the one on the left is a mess and the one on the right is good and would pass the level test. I clean the bed between prints with Iso as normal.
RE: 1st layer print issues from cold
Seems normal to me depending on the generation of your hardware. Everything expands and contracts as it heats and cools. So your bed position will vary in reality depending on if its had a soak heat (longer heating period to let the heat fully expand things in all parts of it). The PINDA sensor is also temperature dependent on where it 'triggers' when it detects metal. Thats probably the biggest factor for your differences.
Later Pinda probes are supposed to be temperature compensated but I never relied on that anyway. In fact I prefer the later PINDA as opposed to the new Super Pinda as it had a thermistor in that could be read and used in start gcode. Afaik the Super Pinda doesn't have the built in thermistor anymore.
I use a similar start up to Bobstro's. In that I move my extruder and probe to about 10mm above the bed and heat it up to around 75. This along with the extruder at 160 for a no ooze warmup means both are heating the area of the pinda. My start gcode then monitors the thermistor in my older style Pinda. When that reaches a set temperature then the bed should be thoroughly warmed through and the probe is at a known set temp. It then goes on to do mesh levelling. This give me a very consistent first layer.
The cons to this process is that on a cold cold day it can take up to 10 minutes for the probe to reach its target temp (35). Most people don't want to wait any extra time but its a once a day thing generally for me on a printing session and only in the winter is it really noticeable. When my printing room is around 12 degrees 🙂
RE: 1st layer print issues from cold
Thanks for the reply. I'm using the latest Mk3S+ and the "Super" Pinda which is supposed to be temperature independent and "Making the first layer calibration and mesh bed levelling much easier and consistent". From my testing it simply doesn't work and I have to follow similar process to the older model and allow the bed to warm up fully.