Hey Jensa, I came in and found this MJ-SF had settled quite a bit on a previous print. I decided that I would pay for uptime to help stir the vat a tiny bit in the print area with the print being pulled all the way up out of the resin and add faster down’s to offset this time.
As Donkey is pretty hourglass I’ve used it for testing. On the previous failed print of Donkey, around the layer it got to the neck of Donkey the head ripped off and failed but not along the slice line it was at (ripped at an angle over 300 +- layers) so there was most likely a stick to the vat.
I may wrongly feel that pulling each slice up and exposing to air seems to give the non cured resin a tiny stir and also a bit of time to again settle removing air. Plus if I have a camera setup to watch a print, I can see if a layer is delaminating. So I just decided to use ultra conservative settings and start to increase. Then I have a recipe for this type of print. kinda foolish and a lot of time i suppose.
Other things I did with this print is hollowed him 2.5mm (ended up scaling him down 75%) when in CW (so ended up being approx 1.875mm) but the hollow I made in MM was very higher res than previous and smooth; Trying to prohibit right angles for peeling forces.
I’m really amazed this print actually was successful and here’s why. This print I started around like 2:30am. Then came in sometime early in the next a.m. to check on the print and the resin had settled a lot. I paused the print and already there seemed to be some general curing of resin on the vat. I raised the Zstage up and scraped this cured resin off, remixed this resin with my MJSF bottle, stirred it up and repoured new mixed resin in on a semi clean PSP v1 vat. Thought this print wouldn’t work from there but curious if I could salvage it. Amazed that the next a.m. it printed. If looking closely at the print you can see where the layer was I did a clean up.
To pause the print is funky and I wrote down my 4 counts of 10+mm up so I could get it to the right spot. I decided to initiate the pause after Kudo had raised him up after the last exposure. However as soon as you press pause, The linear stage appears to stop. As soon as you go to print control and press 10mm UP the linear stage goes down instead as if to finish it’s last command (of down) then immediatley instead of going to expose, it finishes it’s down cycle then does your up 10mm command. In the end I think I got my count wrong and when I resumed It wasn’t down at the vat floor for the first exposure so I panicked and press a 10mm DN again and it was correct again by being all the way down at the vat floor.
I’m truely amazed this print finished as well as it did! I’ve been wondering if there is a way to down the road incorporate a fan that would come down say 2mm off the floor (like swap out the build plate with one that had 2 fans facing down lower it and stir the resin. Replace with print in progress again. Kinda a dumb idea but MJ-SF settles fairly fast (though I’ve nothing to compare it to yet). Lastly I’ve decided it makes more sense to leave the side covers on as the Projector fan is very important for keeping the interior cool. Leave the front cover off to monitor a startup of a print. From the front you can watch the intiial exposure to the vat etc. like you would from the side but also the Projector’s fan is on the front and if you dropped resin in there, would ruin the projector so I have a little piece of plastic that I cover the top case vent with in front over the projector fan so that while cleaning the vat I can keep everything protected.