Resin printer basics
For those that do not know, a resin printer has a tray of goo (resin) in the base, under which is an LCD. The bottom of the tray is a "release film". There is a flat plate suspended above, it lowers in to the tray, a layer of resin is cured, and it lifts off the release film, and then down again for next layer. Eventually the final print hangs from the base plate. There is some messy cleaning and extra curing then to make the final part.
The Saturn had some challenges
I am sure I have griped on this before, but the Saturn had some issues...
The cover was a big top, sides, and front that hinged at the back top. To lift it up you would obviously grab the top sides and push up. The problem is that this motion would easily tip the whole machine back. The trick is grab the bottom sides and pull towards you and then up.
Then the print bed is clamped in placed by a small lever that you push up to release. It is small and stiff, and you push up with palm of your hand. And, you guessed it, this motion would tip the whole machine back. The trick is hold the top back of the machine with one hand while you do this so it does not tip.
However, the print bed is pushed forward when you do this - I never had this happen, but there is a risk it comes off the mount and crashes in to the tray of goo and LCD and smashes it all in a very messy way. So the trick is hold top of machine with left hand, push left elbow to front of print bed, and then lift level with right hand, and hope you do not get covered in resin.
Why does tipping the machine matter? Well, because you have a tray full of goo and if you tip the machine it pours out of the tray in to the machine. This is bad in many ways, not least of which is the machine then leaks goo from the seams for weeks. But also, at the back, directly behind the tray, is the z-axis motor and screw thread, with a big hole around it - so the goo goes right down in to the z-axis motor. This basically burgers that motor. I managed to get working fairly well with a lot of alcohol, lubricant, and running bed up and down for hours. Still not 100% but good enough to be printing again. It needs replacing.
Obviously you have to top up the tray to a level to cover what you are printing, and that makes spills even more easy to happen and more messy when they do.
Finally, changing the release film is a LOT of screws/bolts and very fiddly. Thankfully I realised I rarely need to change if, after a failed print, I use the cleaning cycle which exposes a whole layer you can peel off with any remaining print debris. However, on one occasions it got pierced somehow and I then had to change the LCD screen protector as well as it had resin sealed on to it. Resin printers can be messy.
Also, the print area is not very big, but more than big enough for what I normally print.
Apart from that it is good, and prints well.
An interesting feature is the tray and LCD tip down at the front as part of the release cycle, neatly peeling off the release film from the latest printed layer. Very clever.
The Jupiter
It has a bigger print area, nice.
It has side opening doors, solving the tip back issue.
It has a very long level for release of the bed, which can simply be lifted between thumb and forefinger with no real effort, or risk of tipping the machine.
The z-axis seems to have a cowling to protect from spills.
Even the release film change is a module with a frame and film that simply unclips and a new one clips in place. Costs more, but a lot less effort.
It even has tubing and an auto fill of tray from a bottle at the back, meaning it keeps a low level in the tray - way harder to spill and way less messy when taking off print bed. It can suck that up back in to the bottle for you as well.
I mean that was almost every single gripe I had sorted, well done.
The downside
Sadly there are problems.
It sucks!
That is the main issue. Unlike the Jupiter the print tray and screen do not tilt down to peel off the film from the print, instead the print head just pulls up after the printed layer. It often strains and snaps up. This clearly sucks on the release film, a lot.
After a few small prints I now have creases in the release film which mess up the print.
What is worse is Elegoo's response.
In summary (a) tough, and (b) my fault somehow. I am using all the default settings the app picks knowing printer and resin, and only printing a few small things with which the Saturn had no issues - even so, saying "yes it has a large print area but you can't actually use it" is mental. Where are trading standards when you need them?