【2025 Special Bundle】 SUNLU Official Filament Dryer Box S4,Four-Spool 3D Printer Dehydrator with Rapid Heating, Auto Humidity Control, and Advanced Triple Fan Upgrade, Fits PLA,PETG,ABS,TPU,PA,etc.

I bought the SUNLU S4 bundle to dry my filament before starting my custom 3D projects, and it has been a game-changer. Living in a humid area, moisture is always a problem, but this box keeps everything perfectly dry. I now print directly from the dryer box using the built-in PTFE outlets. The four-spool capacity is amazing I can keep my most-used filaments ready to go at all times. The heating is very fast and it maintains a consistent temperature throughout the box. If you want to eliminate bubbles and stringing in your prints, especially on a fast machine like the Bambu A1, this S4 dryer is worth every penny!

I have been using the JAYO S1 for a while. It is the most basic of filament dryers. To say the S4 is an upgrade would not do it justice. the S4 is in a completely different category altogether. The S4 comes with a few pieces of tubing so that you can run the filament to your printer without exposing to the open air. Also included are some desiccant packets that can be placed inside the compartments under the spools to provide ongoing dehydration. Each of the 4 spool locations has an option for the filament to load out of the top or out of the end. Overall 8 different output holes. Each output is equipped with a connector that is designed to hold a bowden tube securely. For the outputs not in use SUNLU has provided small rubber plugs to keep the unit sealed. The build quality of the unit is excellent. Everything feels solid and well engineered. There is a lot of plastic, but it doesn't feel cheap or brittle, which is important given that it will be going through a lot of heating and cooling. The feet of the unit are actually metal bars instead of just plastic nubs or stick on rubber. It is this attention to detail that makes it feel like a luxury item. Getting started was really easy. I just plugged the unit in and turned it on. After selected the filament type from the menu all I had to do was let it run. The fans start circulating the heated air immediately and all the items in the display tell you the status. You can see the humidity decreasing on the display within minutes. The internal air circulation allows for very fast drying! I appreciate that the display is backlit for easy readability. My favorite feature of this unit is its ability to monitor the internal humidity and initiate drying when it rises above the selected threshold. The default is 50%, but it is can be set to your desired percentage. For humid environments this could be its best feature for sure! Of course you can adjust the temperature and humidity settings once you have selected from 1 of the 6 built in filament options. It is all very easily done from the front display and control panel. If you want you also enable an LED light to indicate when the unit is actively drying. You can also switch the unit to Fahrenheit or Celsius units for display. The unit is large, so plan for it to take up a fair amount of space. My hobby room is packed, so I had to get creative to make room for it. It is approximately 42cm L x 22cm D x 31cm H. I have seen a few other dryer on the market, but with the unit being able to actively dry 4 spools at a time, it is the best I have found.

SUNLU S4 dryer - Even if you don't think you need a dryer, give this one a try, and I promise you will get better results. If you like to switch colors or muti- print, then this is the dryer for you. The S4 is modern looking, with the big LCD screen and green lights that run across the front of the dryer. I usually print PLA and PETG, but the S4 will dry almost all filaments. It has a temperature range of 35C to 70C. The S4 heats up very fast. In fact, twice as fast as the S2 dryer. There are 3 powerful fans, and you can feel the hot air circulating to dry the whole chamber evenly. The S4 comes with several built-in safeties to monitor the temperature and send an alarm if anything is abnormal. The touchscreen allows you to set the dry time, tyes of filament, etc. It has a humidity sensor to display the humidity percentage. You can set to dry for 99 hours or anytime in between. Set it to MOD 2, and it will come on when it reaches 50 percent and dry until it reaches 25 percent and stops. That is a great feature if you plan to print later but want the filaments ready when you are ready. There are two PTFE filament couplers on each end and four on the top. The PTFE tubing is included with the dryer. You just push down or in on the coupler to install or release the tubing. This is great for printing straight frm the dryer. Overall, the S4 has been amazing and has made my printing easier with better results. I would recommend this dryer to everyone!

I love this dryer. I have 4 spools in it at all times. I love that you can set it to automatically go on when humidity rises. Great to keep the filament dry at all times. When you first turn this on, it's going to run for several hours. Sort of initial drying. But you can change that down to just one hour. However, I suggest you run the full initial drying when you insert a new spool. I do the initial drying and then I place them in a vacuum bag with desiccant. After that I just put the color I want at the moment in the dryer and print. It will keep the spool dry while you print. I spool the filament to the printer from the dryer. keep in mind that using the top exit holes can be problematic whe opening the chamber. More so when you close the lid. I wish the filament exit was all on the same side of the machine though. Maybe I can figure a way to do this. To sum it all up, I'm very happy with my purchase and you will too.

Four stars only because when you’re using a multi filament 3-D printer whenever it changes filament it back, feeds the filament and this has no way to wind the schools back up it kind of just create some slack inside the dryer. Other than this, it has caused Little to no clogging. And has really improved my filament and print quality. It has plenty of temperature ranges and humidity settings that you can customize to your liking.

I’ve been using this for the past six months and I would say that it is pretty effective in drying out your spool, most of the time when you press power on it runs on an automatic six hour cycle with the set temperature that you have on your machine. I do not have to re-dry after six hours on a lot of my school however certain filament such as TPU, you have to leave it in there for longer, but overall the machine does what it’s supposed to do as advertise. I am very happy with the Sunlu four spool dryer machine. One addition that I made to the machine is printing a larger handle for the dryer and it is much easier to open that way you can also print a handle to hold the both of the flaps, however, I find that it is not necessary.

I purchased this filament dryer and was quite excited while awaiting its arrival. Upon arrival the two lids were broken off even though there was no damage to the package. The lids are held on by one pin on each side both of which were bent when the lids came off. With my pliers I was able to straighten them out and reinstalled the lids. Drying: This dryer does an awesome job at drying the filaments and was almost plug and play. Feeding: The major issue seems to be with printing from a filament that was in this dry box. I started having major under extrusion which made me investigate. I then realize that it is a nightmare to try and print from this box. It seemed that the bearings don't spin freely which caused the full spools to twist and falloff the rollers. The position of the ptfe holes in relation to the spool creates addition friction that my extruder just cannot overcome. Conclusion: If you are looking to just dry your filament, then this box will get that done no problem. However, of you want to print from the box, then this is not the box for you. I will return this item because one of the reasons why I purchased it was to be able to print directly from the dry box.

This SUNLU S4 filament dryer absolutely works like a champ. It heats up quickly, maintains a stable temperature, and the automatic humidity control is a great feature that I didn’t realize I needed until I had it. I love that it can handle four spools at once—super convenient for anyone who prints often or rotates between materials. The upgraded fans circulate air evenly, and I’ve already noticed a big improvement in print quality with moisture-sensitive filaments like PETG and TPU. The whole unit feels well-built and easy to operate. If you want a reliable, efficient filament dryer that just works, this is a great pick.

Werkt perfect en heeft ook nog een zuinige bewaarmodus. Kan 4 rollen tegelijk drogen / opbergen.

Does as it says , quick , efficient, what else is needed? Thankyou Sunlu !

Verpackung & Design Die SUNLU Offizielle Filament-Trocknerbox S4 kommt ordentlich verpackt an und macht einen hochwertigen Eindruck. Die Box hat ein modernes, kompaktes Design, das sich gut in die Werkstatt oder das 3D-Druckumfeld einfügt. Die Verarbeitung ist robust, und die Tür lässt sich einfach öffnen und schließen. Funktionalität & Nutzung Die 4-Spulen-Trocknerbox ist ein echtes Highlight für 3D-Drucker-Enthusiasten. Ich benutze sie, um verschiedene Filamentarten wie PLA, TPU, PETG, ABS und Nylon zu trocknen, und sie funktioniert wirklich gut. Die Temperaturregulierung ist sehr präzise, und die schnelle Erwärmung sorgt dafür, dass das Filament in kurzer Zeit die optimale Trockenheit erreicht. Besonders praktisch ist die automatische Feuchtigkeitskontrolle, die dafür sorgt, dass das Filament stets in der besten Form bleibt. Leistung & Zuverlässigkeit In meiner Anwendung hat der Filament-Trockner die Feuchtigkeit zuverlässig entfernt und das Filament von Anfang an gut getrocknet. Egal ob PLA oder Nylon, das Filament bleibt auch bei längerer Lagerung optimal verarbeitbar. Fazit Der SUNLU Filament-Trockner S4 ist eine hervorragende Investition für 3D-Drucker, die regelmäßig mit verschiedenen Filamenten arbeiten. Die automatisierte Feuchtigkeitskontrolle, die schnelle Erwärmung und das präzise Temperaturmanagement sorgen dafür, dass das Filament stets in Top-Zustand bleibt und der Druckprozess nicht durch feuchtes Material gestört wird. Ein sehr praktisches und zuverlässiges Gerät, das sich definitiv lohnt.

Droogt filament zeer snel, handig om via 1 van de 8 plaatsen filament te kunnen voeden naar de printer.

The SUNLU S4 Filament Dryer Box is absolutely flawless. It arrived exactly as described and works perfectly right out of the box. The ability to dry four spools at once is a huge time saver, and the results are consistent—no more moisture issues or printing problems. The build quality feels solid, the controls are intuitive, and the temperature holds steady throughout the cycle. I’ve run multiple types of filament through it (PLA, PETG) and every spool came out dry and ready to print with noticeably improved performance. This product does exactly what it promises, and it does it reliably. For anyone serious about 3D printing, this is a must‑have accessory.