FDM vs Resin 3D Printing: Strength, Detail, Price and When to Choose Each

Fantasy Lab 3D runs both kinds of 3D printer, and the first decision on almost every order is which one to use. FDM builds objects from melted plastic filament; resin (SLA) cures liquid photopolymer with light. They produce very different results, and picking the wrong one means paying for detail you cannot see or getting a figurine that breaks. Here is how they compare and how we choose.

How each technology works

FDM (fused deposition modelling) feeds a plastic filament through a hot nozzle and draws the object one layer at a time, like a very precise hot-glue gun. Layers are typically 0.1 to 0.3 mm thick and the nozzle line is about 0.4 mm wide, which sets the limit on how fine a feature can be.

Resin printing (SLA, or more precisely MSLA on most modern machines) shines a UV image into a vat of liquid resin, hardening a whole layer at once. Layers are 0.025 to 0.05 mm and the pixel size is around 0.02 to 0.05 mm, so details several times finer than FDM are routine. After printing, resin parts are washed in alcohol and cured under UV light to reach full strength, a process covered in resin printing after the print.

Side by side

	FDM	Resin (SLA)
Fine detail	Good; visible layer lines	Excellent; layers nearly invisible
Smallest feature	around 0.4 mm	around 0.05 mm
Strength and toughness	Higher; PETG and ABS flex	Lower; standard resin is brittle
Maximum size	Large, up to 25 to 30 cm or more	Smaller, usually under 20 cm tall
Materials	PLA, PETG, ABS, TPU, marble, silk, wood-fill	Standard, tough, ABS-like, flexible, castable
Colours	Huge range, multi-colour possible	Limited palette, usually grey; painted afterwards
Surface out of the printer	Layer texture, may need sanding	Smooth, matte, paint-ready
Heat and sun resistance	Depends on plastic	Can yellow and become brittle in sun
Post-processing effort	Support removal, optional sanding	Wash, cure, support removal, careful handling
Cost per part	Lower, especially for large parts	Higher per volume; efficient for small pieces

When resin is the right answer

Choose resin when the object is small and detail is the whole point:

• Tabletop miniatures, where a face or a sword edge is a millimetre wide (see our post on D&D miniatures)
• Busts and figurines up to about 15 cm where skin, hair and fabric texture matter
• Jewellery masters, rings and pendants for casting
• Dental and medical models
• Small mechanical parts with tight tolerances
• Anything that will be painted to a display standard, because the smooth surface needs no sanding

The trade-off is fragility. Standard resin snaps if you drop it, and thin parts like spear tips or wings flex little before breaking. Tough or ABS-like resins narrow the gap, as described in resin types explained, but they still do not match PETG.

When FDM is the right answer

Choose FDM when the object is larger than a hand, needs to survive use, or should come out in colour:

• Book nooks, lamps, vases, planters and home décor
• Cosplay helmets and armour
• Brackets, mounts, replacement parts and anything load-bearing
• Prototypes and architectural models
• Multi-colour objects, logos and merch printed in coloured plastic
• Large statues and busts, often in marble or textured filament that hides layers

An FDM print of a 25 cm figure can cost less and be far more robust than a resin print of the same size, which would need to be split into pieces and handled like glass. Layer lines are the price; at 0.1 or 0.12 mm they are subtle, and sanding or filler primer removes them. Our guide to layer height explains what different settings look like.

Cost: what actually drives the quote

Neither technology is simply "cheaper". Resin material is more expensive per gram and requires consumables for washing and curing, but a bed full of miniatures prints in the same time as one, so small detailed parts are efficient. FDM material is cheap and large parts are practical, but a big print takes many hours and post-processing adds time. As a rule of thumb:

• Small, detailed, single objects: resin usually wins on quality for a modest premium.
• Large objects: FDM wins on both price and durability.
• Batches of small parts: resin for detail, FDM for colour and toughness.

Every quote depends on size, material, quantity and the finish requested, so ask and we will price both routes if it is a close call.

Combining both in one project

The two technologies often work together. A book nook might have FDM walls and floor in marble filament with resin figurines inside. A cosplay helmet can be FDM with resin emblems and fine trim glued on. A chess set can use FDM for the board and resin for intricate pieces. Fantasy Lab 3D plans this split at the quoting stage, so you get detail where the eye goes and strength where the hands go.

Ready to order?

Not sure which technology your model needs? Send the file or a description through the contact form, or DM Fantasy Lab 3D on Instagram at @fantasylab3d.almaty, and we will recommend FDM, resin or a mix, with a quote for each.