Pressure advance question
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Can pressure advance (M572) be set on the fly during printing?
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Yes. Just be careful not to set it too high without also reducing retraction.
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Thanks, going to make a calibration test object then insert M572 lines with incremental increasing value. Thinking of a single wall inverted cone with a 2 layer sawtooth pattern increasing in width cut out of it starting about 5 layers up and increasing pressure advance slightly at each new sawtooth ledge. Is there a direct inverse correlation for retract I should also use, or will that be another variable permutation to be set, or would it be best to not do retraction across the gaps?
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The reason I warn about retraction is that when you use a large amount of pressure advance, the firmware will start retracting before the end of a printing move that slows to a low speed at the end. When this is followed by a slicer-commanded retraction prior to a travel move, this can result in too much totaL retraction for all-metal hot ends, causing a jam. But if you don't reach this point, then I don't think you need to treat retraction as another variable in your tests.