Short answer: Buy the exact Comgrow SH01 reviewed here only when its two-spool, 40-50 C, 6-12 hour lane matches the current instructions for your exact filament. Buyers starting fresh should also compare Comgrow's current SH02 and SH03: the official SH02 reaches 70 C for two spools, while the SH03 provides two independently controlled chambers for four spools and reaches 85 C. More heat and capacity widen the eligible workflow; they do not replace the filament maker's temperature, time, spool, ventilation, or supervision limits.
The value is simple: two ordinary rolls can stay enclosed, warm, and ready to feed without buying a larger high-temperature machine. The limit is equally simple: 50 C is the maximum listed chamber setting. Capacity does not compensate for a temperature ceiling that is below the material supplier's instructions.
Affiliate disclosure: GoodPrints3D may earn a commission from qualifying Amazon purchases. This review uses the current exact product listing and buyer-fit analysis; it does not claim hands-on laboratory testing. Product details and availability can change.
Check the current Comgrow Filament Dryer Box listing on Amazon
Fast buyer verdict
- Buy it for: two 1 kg spools, lower-temperature drying, print-through feeding, and a compact shared box.
- Skip it for: any material whose current maker instructions require more than 50 C or a longer cycle than the listed timer supports.
- Do not confuse it with: the six-container Comgrow passive-storage kit that previously appeared on this page. That is a different ASIN and a different workflow.
Choose active drying or separate passive storage before you buy
Buy the Comgrow when the spool is wet and its exact drying instructions fit the machine's 40-50 C range. Buy rechargeable silica-gel packets only when the spool is already dry and the missing step is maintaining a separate, genuinely sealed storage bin between jobs.
GoodPrints currently carries 10- and 20-packet options. Size the pack count to the sealed containers you actually maintain. Do not put loose packets in the heated Comgrow chamber, against a hot surface, near a moving spool, or across a filament feed path unless both the dryer and packet instructions explicitly permit that placement.
See rechargeable desiccant on GoodPrints
GoodPrints sells this Shopify Collective product directly. The product page controls current price, inventory, pack options, and fulfillment details.
Comgrow dryer specs that matter
| Listing detail | What it means for a buyer |
|---|---|
| Two 1 kg rolls | Useful when two common materials or colors need conditioning together. Verify unusual spool flange dimensions before buying. |
| 40-50 C adjustable heat | A lower-temperature lane for compatible materials, not a universal engineering-filament recovery box. |
| 6-12 hour timer | Long enough for many routine cycles, but the correct duration still comes from the filament maker. |
| 1.75 mm and 2.85 mm feed paths | Supports both common desktop filament diameters through the listed outlet and tube arrangement. |
| Temperature and humidity display | Shows chamber conditions; it does not directly measure moisture inside the center of a spool. |
| Open vent while drying, close for storage | The listing separates moisture exhaust during heat from the sealed hold state after the cycle. |
The important correction: this is an active dryer
The old page treated this product as a passive dry box. The exact current listing describes internal heating, adjustable temperature, a timed work mode, and moisture removal. That makes it an active filament dryer with a storage function, not a simple desiccant container.
The distinction changes the buying decision. A passive box can help preserve filament that is already dry, but it does not intentionally heat the spool to drive moisture out. The Comgrow unit can run a heated cycle and then act as a more enclosed feed-and-store box. If you only need storage, the dryer, dry-box, and sealed-storage guide explains why a simpler container may cost less and take less power.
Is 50 C hot enough?
It can be, but only for the right spool and the right supplier instructions. The listing names PLA, ABS, and silk-style filament, yet the product title is not a drying recipe. Filament blends, pigments, additives, spool materials, and supplier recommendations vary. The correct temperature is the current instruction for the exact filament, not the highest setting on the machine.
A 50 C ceiling is attractive for routine PLA moisture control and other lower-temperature cycles. It becomes a hard boundary when a supplier calls for more heat. Many PETG, TPU, nylon, PC, and carbon-fiber blends may require a hotter process than this box can provide. Do not extend the timer and assume that low heat always substitutes for the specified temperature.
If PETG or TPU is the recurring problem, use the PETG and TPU filament-dryer guide to compare current hotter options. The Sovol SH02 review covers a different two-spool lane for buyers who need more temperature headroom.
Two-spool capacity: when it helps
Two-spool capacity matters when both rolls are active in the same workday. A printer owner alternating between two colors, running a main material and support material, or keeping a backup roll ready can avoid serial drying cycles. The box also consolidates two feed paths into one bench footprint.
It matters less when only one spool is ever open. A single-spool dryer may be smaller, easier to place, and cheaper. It also does not make sense to mix two materials in one chamber when their approved drying temperatures or times disagree. Because this unit does not provide independently controlled chambers, both loaded spools share the same cycle.
Check physical fit as well as weight. The listing gives an inner size of about 9.29 by 6.49 by 9.13 inches and describes two 1 kg rolls, but specialty reels can be wider or have larger flanges than a standard spool. Measure the actual rolls you plan to use.
Dry while printing, then store correctly
The outlet arrangement uses a silicone sheath, PTFE tube, and plugs, according to the listing. That supports feeding from the enclosed box and closing unused outlets. The listing also instructs users to open the sealing vent while drying so moisture can escape, then close it when the box is not running to help maintain the stored environment.
This is a useful workflow boundary. Keeping every port sealed during a heated cycle can trap moisture-laden air. Leaving the vent open after drying weakens the storage state. Follow the current manual and listing instructions rather than treating one lid position as correct for every stage.
A displayed humidity number is not proof that the spool core is dry. Chamber air responds faster than filament. Judge the result with a controlled print and the actual failure symptoms. The filament-drying workflow guide shows how to compare before-and-after behavior without changing five slicer settings at the same time.
SH01 vs SH02 vs SH03: which Comgrow dryer should you buy?
The SH01 remains the budget-fit choice only when 50 C is enough. Comgrow's current official lineup adds two materially different upgrades: the two-spool SH02 raises the ceiling to 70 C, while the four-spool SH03 separates the load into two independently controlled chambers and reaches 85 C. That turns the decision from “which box is bigger?” into a heat, queue, and mixed-material workflow choice.
| Model | Verified operating envelope | Best fit | Stop rule |
|---|---|---|---|
| SH01 reviewed here | Two 1 kg spools, shared 40-50 C chamber, 6-12 hour control | Lower-temperature PLA-first work and two rolls that accept the same cycle | Skip when either spool requires more than 50 C or a different simultaneous cycle |
| Current SH02 | Two 1 kg spools, one 150 W PTC system, 40-70 C, up to 98 hours, nine material presets | Two-spool buyers who need more temperature and time headroom without moving to four rolls | It is still one shared chamber; presets do not prove the correct cycle for every blend or spool |
| Current SH03 | Four 1 kg spools in 2+2 independent chambers, separate controls, 200 W + 200 W PTC heat, 45-85 C, up to 98 hours | Busy benches drying different material families at the same time or clearing a larger queue | Four-spool capacity is wasted when the real workload is one roll; confirm power, footprint, feed routing, and exact spool fit |
Heat does not erase material limits. Use the exact filament supplier's current cycle, confirm the reel itself tolerates that temperature, and qualify a representative print before trusting a consequential part. The chamber display reports conditions in the dryer, not moisture at the spool core and not finished-part strength, sealing, chemical resistance, fatigue life, dimensional stability, food safety, electrical safety, or regulated-use acceptance.
Safety boundary: Comgrow documents over-temperature and fan-monitoring controls on its current models, but those are protective features—not proof of zero fire risk. Use the specified power hardware, preserve required clearance and ventilation, keep outlets and moving spools unobstructed, inspect the unit and reel before each long cycle, and follow the current manual's supervision and stop instructions.
Official lineup check: October 4, 2026. Model availability and specifications can change; verify the selected product page before buying.
When the SH03 route is the better next step
Move to an SH03 only when the bottleneck is three or four loaded spools, or two material families that need different cycles at the same time. The current Comgrow and Sovol SH03 product pages both describe a four-spool, two-zone, 45-85 C workflow. Use the Sovol SH03 four-spool, dual-zone review to check the exact buyable route, reel width, outlet routing, plug region, seller and warranty path, and the conflicting 1.75 mm versus 2.85 mm source wording before checkout.
Keep the SH01 reviewed here when two spools can safely share one cycle at or below 50 C. Choose the two-spool SH02 when temperature or cycle length is the real limit but four positions would sit unused. Two independent SH03 chambers improve scheduling; they do not make every spool, filament grade, outlet path, or available temperature safe.
Who should buy the Comgrow dryer?
- PLA-first makers with two open rolls: the listed heat range can align with many lower-temperature PLA drying workflows.
- Shared benches: two common spools can stay enclosed and feed from one controlled box.
- Print-through users: the feed ports and internal rollers matter when a spool should remain enclosed during a job.
- Buyers who want dry-and-store in one unit: the vented heated cycle and closed hold state can replace separate handling steps.
- Owners who will verify settings: the product makes sense when the exact filament instructions fit within 40-50 C and 6-12 hours.
Who should skip it?
- Engineering-material users: nylon, PC, and many filled blends often need a hotter qualified process.
- Independent-temperature workflows: both spools share one chamber and one temperature setting.
- Passive-storage-only buyers: sealed containers and maintained desiccant may solve the job with less equipment.
- Large-spool users: 2 kg, 3 kg, or unusually wide reels need a box designed around their actual dimensions.
- Anyone expecting the display to prove dryness: chamber humidity is a useful operating signal, not direct moisture measurement inside filament.
A five-step proof before trusting the workflow
- Read the filament maker's current temperature and duration guidance.
- Confirm the required temperature is no higher than the Comgrow box's listed 50 C ceiling.
- Load one representative spool, open the vent as directed, and run the approved cycle.
- Print the same small model with the same printer and profile used before drying.
- Compare popping, surface texture, stringing, extrusion consistency, and layer behavior before deciding that moisture was the cause.
If the result does not improve, do not keep adding heat blindly. Use the still-prints-wet diagnosis to separate a real moisture or dryer-capacity limit from temperature, retraction, flow, a partial nozzle obstruction, contaminated filament, or a mechanical feed issue.
Close the moisture-control loop after the drying cycle
- Use the Comgrow dryer when active heat and airflow are required and the exact spool's approved cycle stays within the machine's limits.
- Move an already-dry spool to sealed storage when it will sit between jobs and you do not need print-through feeding from the dryer.
- Add rechargeable desiccant to that separate container when passive humidity maintenance is the remaining gap.
- Buy neither yet when the container leaks, the spool still fails after a qualified cycle, or the real cause may be nozzle, profile, or feed-path related.
Use the filament storage guide to validate the container and handling routine. Regenerate packets only by the current product instructions, let them cool as directed, and replace damaged packets rather than returning them to filament storage.
Final verdict
Buy the Comgrow Filament Dryer Box when two-spool capacity and a 40-50 C routine drying lane match your real materials. It is a straightforward dry, feed, and store appliance for lower-temperature workflows, with clearer value than the old page's passive-box framing suggested.
Skip it when the exact spool needs more than 50 C. The shared chamber, 12-hour listed timer ceiling, and lower heat range are buying boundaries, not details to discover after wet nylon or TPU has already wasted a print.
See the current Comgrow Filament Dryer Box listing on Amazon