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Here’s a purchase mistake that’s easy to make and annoying to unwind: buy the Saturn 4 Ultra, buy “the popular wash and cure station” because that’s what every roundup recommends, then discover the build plate doesn’t fit in the wash chamber. Not “fits if you’re careful.” Doesn’t fit. This isn’t a hypothetical. It’s a documented problem with the specific station Elegoo itself bundles with the printer on some listings, and the fix some owners settled on is filing 6mm of plastic off both sides of the build plate’s resin shield.
If you already own a printer and just need a station, the general wash and cure station roundup covers the field for Saturn-class and smaller machines. This article is narrower on purpose: it’s for Saturn 4 Ultra owners specifically, because the Ultra’s larger plate changes which stations are actually viable. For resin recommendations once you’ve got the washing sorted, best resin for miniatures is the place to start.
The Plate Is the Whole Problem
Elegoo’s own spec sheet puts the Saturn 4 Ultra’s build plate at 211.68mm x 118.37mm (the 16K model this site links), with a build height of 220mm. That’s a meaningfully bigger footprint than the older Saturn line, which is why a station sized for the standard Saturn doesn’t automatically carry over.
Case in point: the Mercury Plus 2.0, still the most-recommended station in this niche and the top pick in our general roundup, is the one to check first, because it’s the station most people already own or buy by default. Whether it takes the 4 Ultra’s 211.68mm x 118.37mm plate depends on its listed wash capacity, so check Elegoo’s current listing against the plate before you assume it carries over from an older Saturn. If the listed capacity doesn’t clear the plate, it’s the wrong station for the 4 Ultra, regardless of how often it gets recommended for Saturn-class printers generally.
The more surprising case is the Mercury XS, which Elegoo bundles directly with the Saturn 4 Ultra on some Amazon listings. Community reports (including a printable build-plate mod shared for exactly this purpose) describe the stock plate not fitting into the Mercury XS wash container out of the box, with owners shaving material off the plate’s resin shield to make it clear the basket. If you’re buying the printer-plus-station bundle expecting a plug-and-play fit, know that going in.
What Actually Clears the Plate
Two stations have chamber dimensions that comfortably clear the 4 Ultra’s plate, per their own published specs.
Elegoo Mercury Plus V3.0. This is the version Elegoo pairs with the Saturn 4 Ultra on its own current bundle listings, and the spec sheet backs that pairing up: a rated wash volume around 230mm x 135mm x 260mm and a curing area around 250mm x 290mm. Set against the Ultra’s 211.68mm x 118.37mm plate, that’s real clearance on both axes rather than a tight squeeze. Worth flagging so you don’t grab the wrong Mercury by accident: this is the V3.0, not the Plus 2.0 from the general roundup. Same product family, different generation, and the wash chamber is roughly double the 2.0’s capacity.
Anycubic Wash & Cure 3 Max. Anycubic’s large-format station, rated around 305mm x 165mm x 300mm, with the manufacturer listing it as compatible with the Saturn series among other large-format printers. It’s built for machines bigger than the 4 Ultra too, so you’re not running it near its limit. If you’re already in the Anycubic ecosystem for resin or accessories, or you print large terrain and busts alongside 28mm miniatures, the extra headroom is worth the larger footprint on your bench.
What to Skip (or Buy With Eyes Open)
Mercury Plus 2.0. Great station. Check its listed wash capacity against the 4 Ultra’s plate before buying it for this printer, and skip it if it doesn’t clear.
Mercury XS, if you’re expecting stock fit. The bundle exists and Elegoo sells it alongside the Ultra, so it isn’t a scam or an obvious mismatch on paper. But going in aware of the reported fit issue (and the plate-trimming workaround the community has published) will save you a frustrating first week. If you’d rather not modify the build plate that came with a printer you just paid for, spend the extra money on the Mercury Plus V3.0 or the Anycubic Max instead.
Do You Actually Need to Size Up?
Not everyone running a Saturn 4 Ultra needs the bigger station on day one. If you’re mostly printing single busts, one hero model at a time, or partial plates while you’re still learning the printer’s quirks, your existing Mercury Plus 2.0 or equivalent might genuinely get you through the first few months. The upgrade becomes worth it the moment you start running full plates regularly, because that’s when the chamber math stops being optional.
A useful gut check: if you find yourself splitting a print job into two smaller plates specifically so the wash station can handle it, that’s the station telling you it’s undersized for how you’re actually using the printer. At that point the time lost to extra wash-and-cure cycles adds up faster than the price difference between a Mercury Plus 2.0 and a V3.0.
Comparison Table
| Station | Wash Chamber (approx.) | Fits Saturn 4 Ultra Plate? | Approx. Cost | Notes |
|---|---|---|---|---|
| Elegoo Mercury Plus V3.0 | 230 x 135 x 260mm | Yes, comfortably | $70-100 | Elegoo’s own current pairing for the 4 Ultra |
| Anycubic Wash & Cure 3 Max | 305 x 165 x 300mm | Yes, with room to spare | $90-130 | Rated for large-format printers generally |
| Elegoo Mercury XS | ~7L capacity, plate fit disputed | Reported no, without modding the plate | $60-90 (bundle pricing varies) | Community fit mod exists; go in aware |
| Elegoo Mercury Plus 2.0 | Check Elegoo’s listing | Check against the plate | $45-65 | Verify fit before buying |
Prices move around with sales and bundle pricing, so treat the ranges above as ballpark, not quotes.
Buying Considerations Specific to the 4 Ultra
Chamber volume isn’t just about the plate footprint. Height matters too. A 220mm build volume means tall prints, terrain stacks, and busts with long support trees need vertical clearance in both the wash basket and the cure chamber, not just enough room in X and Y. Check the cure area dimensions specifically, not just the wash chamber, since some stations are more generous on one than the other.
IPA volume scales with chamber size. A bigger wash chamber needs more isopropyl alcohol to fully submerge a print, which means more IPA on hand and more IPA to eventually reclaim or replace. If you’re moving up from a standard Saturn to the 4 Ultra, budget for a proportionally bigger IPA supply, not just a bigger station.
You don’t have to wash the whole plate every time. If you’re only running a partial plate, or a single bust, a larger station is overkill for that print, but it’s still the right call if you regularly run full 4 Ultra plates. Buy for your typical print, not your smallest one.
Bundle pricing can undercut buying separately, but read what’s actually included. The Saturn 4 Ultra plus Mercury Plus V3.0 bundle is frequently priced close to the printer alone, which makes it worth checking before buying the station on its own. Just confirm the listing specifies the V3.0, not an older Mercury generation, before you add it to the cart.
Frequently Asked Questions
Can I just use my old Mercury Plus 2.0 for prints that don’t use the full 4 Ultra plate? For a single small print pulled off the plate before washing, sure, it’ll physically fit in a smaller chamber. If the chamber can’t take the full plate, the problem is washing the full plate at once, which is the point of upgrading to a large-format printer in the first place. If you’re constantly pulling individual prints to fit a small washer, the station is fighting the printer’s whole reason for existing.
Does the Mercury Plus V3.0 work with smaller printers too, or is it 4-Ultra-specific? It works with any 405nm MSLA resin printer regardless of brand. It’s just sized generously enough that a standard Saturn or Mars plate has plenty of room in it. You’re not locked into pairing it only with the 4 Ultra.
Is the plate-trimming mod for the Mercury XS actually necessary, or can I just angle the plate in? Reports from owners who’ve dealt with this describe the plate not clearing the basket at its stock dimensions, which is why the trim mod exists at all rather than people just finding a workaround angle. If you’d rather not modify hardware you paid for, it’s simpler to buy a station sized for the plate as-is.
Do I need a bigger UV cure array for a 16K printer, or is that unrelated to resolution? Unrelated. Cure array size and coverage are about the physical dimensions of what you’re curing, not the printer’s pixel resolution. A 4K printer and the 16K Saturn 4 Ultra both cure resin the same chemical way; the cure station just needs to physically reach every surface of whatever you printed.
Can I mix and match: wash in one station, cure in another? Yes, and some hobbyists do exactly this if they already own a separate UV curing lamp or chamber and just need a wash basin big enough for the plate. The wash and cure functions don’t have to come from the same unit, though a combined station is usually more convenient for most people.
After the Wash
Once you’ve got a station that actually fits the plate, the workflow details (cure times by resin type, how long to air-dry before curing, when to replace contaminated IPA) are the same regardless of chamber size. The beginner’s guide to resin miniature printing covers that end to end, and the resin printing safety guide has the correct process for IPA handling and disposal. If you’re still deciding whether the 4 Ultra itself is the right printer, the full Saturn 4 Ultra review breaks down where the resolution and build volume actually earn their keep. And if you’re choosing between stations for a standard Saturn instead, the Mercury Plus 2.0 vs. Phrozen CW3 vs. Anycubic Wash & Cure 2.0 comparison is the right page.