Best Upgrades for Prusa MK4S: Worth the Investment?

The Prusa MK4S is a mature, refined printer that Prusa has been iterating on for years. It does a lot right out of the box — excellent print quality, reliable operation, great community support, and open-source firmware. But there are upgrades that can push it further, whether you need multi-material capability, better material compatibility, or improved workflow.

I have spent considerable time with the MK4S and have tested many of the popular upgrades. Here is what genuinely improves the printer and what you can skip.

The Big One: MMU3 (Multi Material Upgrade)

Cost: ~$300 Worth it? Conditionally yes — if you understand what you are getting into.

The Prusa MMU3 adds multi-material capability, supporting up to 5 filaments. This is Prusa's third generation of multi-material hardware, and it is significantly more reliable than the MMU2S it replaces.

What it does well:

• Multi-color prints look stunning
• Automatic filament switching is more reliable than previous versions
• Soluble support material (PVA with PLA, BVOH with PETG) for complex geometries
• Filament type switching (PLA body with TPU grip sections, for example)

What to expect:

• The purge tower wastes significant filament on multi-color prints
• Print times increase with each color change
• Occasional jams still happen, though less frequently than the MMU2S
• Initial calibration and tuning takes patience

According to the Prusa blog's MMU3 review, the MMU3 achieves a reliability rate above 95% for standard PLA multi-color prints when properly calibrated — a major improvement over previous generations.

My recommendation: Get the MMU3 if multi-color or multi-material printing is genuinely important for your work. Do not get it "just to have it" — the added complexity is only worth it if you will use it regularly.

Nozzle Upgrades

Prusa Nozzles

The MK4S uses the Prusa-proprietary Nextruder nozzle system, not standard V6 nozzles. This limits your options to Prusa-compatible nozzles, but there are still meaningful upgrades available.

Hardened Steel Nozzle

Cost: $10-15 Worth it? Yes, for abrasive filaments.

Prusa sells hardened steel nozzles for the Nextruder. If you print carbon fiber, wood fill, or other abrasive materials, this is a mandatory upgrade. The stock brass nozzle will wear out within a few rolls of CF filament.

Different Nozzle Sizes

The stock 0.4mm nozzle is versatile, but consider adding:

• 0.6mm nozzle for faster functional prints — reduces print time by 30-40% with minimal quality loss for non-cosmetic parts
• 0.25mm nozzle for ultra-fine detail work — miniatures, small text, intricate geometry

Nozzle changes on the Nextruder are quick (under 5 minutes when hot), so having multiple sizes on hand and switching as needed is practical.

Build Surface Options

Textured PEI Sheet

Cost: $25-35 Worth it? Highly recommended.

The MK4S ships with a smooth PEI sheet that produces glossy bottom surfaces. The textured PEI sheet from Prusa provides:

• Better PETG adhesion without the risk of bonding too strongly
• A uniform textured bottom finish that hides minor first-layer imperfections
• Easier release of flexible filaments (TPU)

I keep both sheets and swap based on the job. Glossy PEI for display pieces, textured PEI for everything functional.

Satin PEI Sheet

Cost: $30-40 Worth it? A nice middle ground.

The satin sheet offers a finish between smooth and textured. It works well with most materials and produces an attractive semi-matte bottom surface. If you only want to buy one sheet, the satin is the most versatile option.

According to the Prusa Knowledge Base, the satin sheet provides the best all-around adhesion for the widest range of materials, making it ideal for users who frequently switch between PLA, PETG, and other filaments.

Enclosure

Cost: $50-200 (DIY) or $700+ (Prusa Original Enclosure) Worth it? For ABS/ASA/nylon printing, yes.

The MK4S is an open-frame printer. For PLA and PETG, this is fine. For ABS, ASA, nylon, and polycarbonate, an enclosure dramatically improves print quality by:

• Maintaining stable ambient temperature (reduces warping)
• Reducing drafts that cause layer adhesion issues
• Containing fumes (important for ABS and ASA)
• Reducing noise

Enclosure Options

Prusa Original Enclosure: The premium option — purpose-built, includes temperature control, and integrates with the printer's firmware. Expensive but polished.

DIY IKEA Lack enclosure: The classic community option. Two IKEA Lack tables ($10 each) stacked with acrylic panels on the sides. Cheap, effective, and well-documented by the community.

Third-party fabric enclosures: Fabric enclosures provide basic draft protection and heat retention without the permanence of a rigid enclosure. Good for occasional ABS use.

Filament Management

Filament Dryer

Cost: $40-60 Worth it? Essential for PETG, TPU, and nylon.

A Sunlu S2 filament dryer or similar keeps hygroscopic filaments dry and feeds directly to the printer. This is not MK4S-specific but is one of the best investments for any printer that handles moisture-sensitive materials.

Improved Spool Holder

Cost: Free (printable) Worth it? If the stock holder gives you trouble.

The MK4S stock spool holder works for standard 1kg spools but can struggle with heavier 2kg spools or oversized spool diameters. Community-designed holders with bearing rollers and wider compatibility are available on Printables.

Software and Firmware

OrcaSlicer

Cost: Free Worth it? For advanced users, yes.

While PrusaSlicer is excellent and closely maintained by Prusa, OrcaSlicer offers additional features:

• More granular control over pressure advance and input shaping
• Additional infill patterns
• Better multi-material purge optimization (useful with the MMU3)
• Community-maintained profiles for the MK4S

Firmware Updates

Cost: Free Worth it? Always.

Prusa regularly releases firmware updates that improve print speed, quality, and reliability. Keep your MK4S firmware current through the printer's settings menu or the Prusa Connect interface.

Recent firmware updates have added speed improvements that make the MK4S significantly faster than its initial release performance. If you have not updated in a while, a firmware update alone can feel like an upgrade.

Lighting

LED Strip

Cost: $15-25 Worth it? Yes, for visibility.

The MK4S does not have built-in lighting. A USB LED strip mounted across the top frame improves visibility dramatically for:

• Monitoring print progress and quality
• Watching first layers from a distance
• Camera recordings and timelapses
• Working on the printer during maintenance

This is a minor upgrade that you appreciate every single time you use the printer.

Connectivity

Prusa Connect

Cost: Free Worth it? Yes.

Prusa Connect is Prusa's remote monitoring and control platform. The MK4S connects via WiFi and allows:

• Remote print monitoring with the built-in camera
• Starting and stopping prints remotely
• Print queue management
• Fleet management for multiple printers

The Prusa Connect platform is free and adds significant convenience, especially for overnight prints and print farm operations.

OctoPrint (Alternative)

Some users prefer OctoPrint for more control and plugin support. This requires a Raspberry Pi and additional setup, but provides:

• Third-party plugin ecosystem
• Custom automation
• Advanced monitoring and alerting

For most users, Prusa Connect is sufficient and requires zero additional hardware.

Printable Upgrades

Before spending money, print some improvements. Popular printable MK4S upgrades include:

• Cable management clips and chains
• Tool holders that attach to the frame
• Improved filament path guides
• Webcam and phone mounts
• Spool holder improvements
• Dust filter for the filament path

Search 3DSearch for "Prusa MK4S upgrade" to find printable mods across all model repositories.

What NOT to Upgrade

Motion System

The MK4S motion system is already excellent. The input shaper compensates for resonance, and the linear rods provide consistent movement. There is no practical motion system upgrade that improves print quality.

Hot End

The Nextruder is Prusa's latest hot end design and handles most materials well. Swapping to a third-party hot end would require significant modification and void your warranty without meaningful benefit.

Bed

The spring steel magnetic bed system works well. The heated bed reaches temperature quickly and maintains even heating across the surface. No upgrade needed.

Extruder Gears

The Nextruder's extruder gears are designed for the system and work well. Aftermarket gears are unnecessary.

My Recommended Upgrade Priority

1. Textured PEI sheet ($25-35) — immediate versatility improvement
2. LED lighting ($15-20) — daily quality-of-life improvement
3. Filament dryer ($40-60) — essential for material variety
4. Hardened steel nozzle ($10-15) — if you plan to use abrasive filaments
5. 0.6mm nozzle ($10) — for faster functional prints
6. Enclosure ($50-200) — if ABS or ASA is in your plans
7. MMU3 ($300) — if multi-color/multi-material is important

Total for full upgrade path: approximately $450-640

According to the r/prusa3d subreddit, the most commonly recommended first upgrades for MK4S owners are the textured sheet and LED lighting — both provide immediate, tangible improvements for minimal cost.

Is the MK4S Worth Upgrading vs. Buying a Different Printer?

If you already own a MK4S, upgrading makes sense. The printer is excellent hardware with a strong ecosystem.

If you are deciding between buying a MK4S with upgrades versus a Bambu Lab P1S (which includes an enclosure and comparable features), the decision comes down to priorities:

• Prusa MK4S: Open source, better community, excellent documentation, strong customer support, repairable
• Bambu Lab P1S: Faster out of the box, included enclosure, tighter ecosystem, less user-serviceable

Both are excellent printers. The MK4S with the right upgrades is competitive with anything in its price range.

Final Thoughts

The Prusa MK4S does not need upgrades to produce excellent prints. It does, however, benefit from targeted improvements that expand its capabilities. The textured PEI sheet and LED lighting are universal improvements. The filament dryer and hardened nozzle expand material options. The MMU3 and enclosure add major capabilities for specific workflows.

Upgrade based on what you actually need, not based on FOMO. The MK4S is a workhorse printer that rewards careful, intentional investment more than it rewards throwing money at every available accessory.