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I thought it might be useful to people to learn how the new Saturn 2 printer performs in terms of the actual printing experience. When a new printer comes out, various outlets on the web typically gush with reviews that largely just recapitulate what can see for yourself on the manufacturer's website: 'noise' in other words. Sources of genuinely useful information like Dom (3DPrintingPro) and Uncle Jessy are perenially reliable exceptions when it comes to evaluating the state of the art in terms of the rigours of printing, however - for clearly understandable reasons - they tend to focus almost entirely on the production of figurative subjects, the organic nature of which have demands quite distinct from the kind of planar and curving shapes which modellers working on aircraft, ships and so forth frequently find themselves grappling with. I don't intend this review to be a detailed analysis of printing strategies per se, but having spent much of September calibrating a Saturn 2 for printing aircraft kits, I thought it might be useful to share with people what I've found with regard to quality control and daily usage when printing at 8K for modelling purposes. Having bought the original Mars a few years ago, and a Mars 2 subsequently, I've a prolonged baseline from which to evaluate the current generation of machines. The first question to get out of the way is simply my reasons for buying a much more expensive machine: I want to print bigger subjects. I want an increase in resolution for smaller details. I need to print small runs of parts to supply kits to others. If you can tick two of the above items then you may want to consider the investment, otherwise (in Elegoo terms but translate for other manufacturers) the likes of Mars 2 & 3 remain perfectly suitable for the hobby at present in my view. Scale The Saturn 2 is a big machine for which you will need expanded workspace - not simply for the machine itself but for all the associated cleanup activities: The ensemble has a reassuringly robust 'heft' in the hand when setting up, more like an industrial rather than hobby tool. Z-axis, build plate and resin tank have proved robust and stable at all times. When placed against the build plate for the Mars 2, that of the Saturn 2 has nearly three times the print surface area: I noticed a tiny squeak emanating from the z-axis during the very first print (a little lithium grease rubbed along the z-axis screw and channels cured this) otherwise it printed happily straight out of the box with no fuss. Another issue related to scale is keeping the resin within the required temperature range, especially on long prints. As I've done with previous printers the Saturn 2 is running in a salvaged cupboard for insulation with heat supplied by a 30W reptile heating mat. Operation Changover in terms of removing printed parts and re-levelling the cleaned build plate for the next run is straightforward, the larger bolts on the build plate making the latter operation more rapid/less fiddlly than the M2/3 when tightening both axes. In addition the supplied levelling card works perfectly well in terms of calibrating the z-axis height for printing. Every print (I've done about 25 runs so far) has worked without any FEP adhesion/sticking, whilst printed parts remain firmly attatched to the build plate surface at all times. I've been printing for the last three weeks just with standard Elegoo grey (unsure yet whether it's worth shelling out for 8k resin in terms of an observable increase in quality) without issue. In fact keeping the same resin I've used since first getting the original Mars printer gives excellent continuity in terms of assessing what improvements in output quality are due to the machinery rather than consumables. There's no evident vignetting in the light source by which to tell parts printed in the centre of the plate from othose around the periphery, despite the increase in screen size. Using a closed cupboard I don't find any noticable resin odour (it does come with a replaceable charcoal filter as well). That said it isn't always what you can smell that does you wrong (was that a blues number? ) so I keep the vent light window open during printing and open the casement in the morning to completely air the space. This section is so short because, quite simply this printer works well, is straightforward to set up and easy to use. Output Quality This is the important bit you always want to know about when buying a printer of course but don't forget that output quality depends as much on the skill of the operator as on the machinery alone. That's why you should ignore fools clogging forums with their 'my perfect exposure setting' on a resin validation print. Exposure is only one of several inter-related variables eg. part orientation, anti-aliasing, and layer-height. The only valid test I find is the actual part itself -adjusting these related parameters based upon experience. In other words: successfully using this process requires the user to be sensitive to a balance of factors. On some occasions I will over-expose a print by 10-15% to increase smoothness where sharpness is less of an issue, and under-expose by the same value to pull out maximium sharpness for the layer-height. It always depends on the nature of the part in question. Is the Saturn 2 better than previous printers I've owned then in terms of quailty? The short answer is 'yes', but - as in all such cases - it depends what you mean by the word 'better'. Let's break this down: Resolution: I am definitely finding that the finer resolution offered by the S2 is yielding significantly better reproductions than previously. Although these 1/72 Avon engines printed up very nicely on the Mars 2, the crispness of detail here on features like edges, bolts and injectors is noticably better: The best way I can try and portray this difference in quality in objective terms is that where features contain a lot of fine detail, it's akin to when you've slightly adjusted a pair of binoculars and the scene suddenly pops into focus, making you realize it wasn't quite in focus before. You don't really notice the absence until what's missing is present.... Smoothness: we can make a fetish of resolution and simply assume that by decreasing layer height on every occasion we will simply arrive at smoother prints, which simply isn't the case. For large airfoil like wing shapes shapes and compound curves I frequently find that a 50μm layer height works better with judicious use of anti-aliasing* and print orientation, in terms of both quality and printing-time, when compared to lower layer-heights. The Saturn 2 is no exception to this rule and at 50μm I find a defined quality difference in smoothness when it comes to the presence ( or rather, absence) of layering artefacts on things like airfoil shapes. Oblique light being the harshest crtitique of imperfection I took the following couple of shots under such conditions in order to cruelly expose any such issues: Truth to be told, using the Saturn 2 there aren't really any! Only the faintest of traces can be seen here whereas under identical conditons of orientation, exposure and alti-aliasing on the Mars 2 I was finding sufficient evidence of banding on several parts where the surface gradually altered in curvature that required some light planing /sanding to remove layer evidence. *Anti-aliasing is a separate topic in its own right of course but worth noting here that I've found significant and useful differences in terms of print quality achievable with the Saturn 2 when using Lychee and Chitubox, in ways that didn't previously seem to be a factor with the Mars 2. Using identical exposure and layer-height settings, for features like the engines I found superior results using Chitubox's slicing and anti-aliasing functions, whereas for interior cockpit detail and wingfold mechanisms, Lychee's slicing and anti-aliasing routines proved markedly superior. It should also be added here that as for exposure, there is no 'golden' anti-aliasing setting in either software, different shapes, curves and angles require settings quite distinct from one another on every occasion. Summary This is the third resin printer I've owned and was the easiest of the lot to set up and print from straight out of the box. It's robustly-engineered with the metal parts fitting together well, giving you confidence in handling and operation at the 8k level. The user interface itself remains the same simple one which Chitubox have kept faith with on their line i.e., straightforward and easy to understand. The machine is quiet and unobtrusive when running. Finished results with printing aircraft parts have been uniformly excellent - and I do mean uniformly excellent - over the course of the last month of testing, without a single print failure. Smoothness and levels of detail are the best that I've been able to achieve with any printer so far (with the caveat that it took a lot of test printing with various parts to get the best combinations dialled in and saved as printing presets). Anyway, I hope this is of help with anyone considering a purchase who wanted to know the experience of working with this printer. Kind regards, Tony