SLA Rigid Engineering Resin

Tough, smooth and accurate

Overview

Rigid resin is a strong engineering plastic that is formed with UV light. Its raw state before printing is in liquid form as with all light based 3d printing resins. It has properties that we have found are suited well for a range of difficult geometries including forms prone to warping.

It has a remarkably low shrinkrate of 0.2-0.7% which is how we produce forms within tolerance and free of warping. Its scores well in tensile strength so its strong and rigid. Its elongation percentage prevents it from becoming brittle and provides a little flexibility. Its highly machinable meaning all secondary operations like planar sanding, drilling, milling and tapping can be performed with greater ease. Parts under 100 grams are usually printed solid, for parts over 100 grams we will hollow the object for you, this is neccessary to prevent printing failures.

We normally apply a wall thickness of 3mm giving it more then adequate strength. Typically this resin is best suited to applications where fine detail and surface quality is most important. If you want a 3d print that most closely represent a real injection molded consumer product then this is the material for you.

Colors – Black, white & grey

Max Print Size – 156(Y) x 278(X) x 290mm(Z)

Printing Technology – SLA Resin

Lead Times – Overnight or 2-4 working days

Properties

Dimensionally Accurate

It has a particulary low shrink rate (0.2-0.7%) ideal for functional parts that require high dimensional accuracy. Most standard resin’s on the market have a shrink rate of 2% and up

Tough & Rigid

Its strong and impact resistant like ABS. It has a shore 85D hardness making it stiff. Although it is stiff especially in thick areas it is still touch enough to withstand some bending.

Chemically Resistant

It offers good chemical resistance, its non-reactive with paint, oil, machine greases, water, glue, spirits and silicone. Nearly all paints adhere well to the surface, it can be glossed and it works perfectly for silicone molding applications.

Slightly Flexible

Non-brittle with a little flexible (having a 37% elongation at break). Just enough give to improve impact strength and resist permanent deformation.

Easily Machinable

Its very easily machined, you can drill holes, tap threads, mill or turn with CNC and lathe. This is handy when for example you model a hole location incorrectly, instead of reprinting you can drill the hole where it needs to be. If the hole is too tight, you can redrill with a larger bore.

Silicone moldable

Rigid Resin is always the first choice with silicone molding. This rigid resin is detailed and smooth and doesnt inhibit the curing of most tin-based and many platinum based silicones.

Tolerance/Accuracy

The vast majority of our prints are with +-0.2mm (or +-0.2%). We offer a garuanteed tolerance of +-0.3mm (or 0.3%), however 95% of our parts are significantly more precise than the minimum tolerance we offer.

Generally speaking if the part is less that 100mm long then it will be within 0.1mm of its target size.

In rare cases some geometries are prone to warping which can lead to results outside of the garuanteed tolerance, if this is the case we can usually reorientate the print direction to compensate. This resin also has a very low shrink rate which we’ve found mitigates warping more than any other resin we use or have tested.

Technical Data Sheets

Download the suppliers Technical Data Sheet & Material Safety Datasheet

Mechanical Properties

Test Method

Value

Ultimate Tensile Strength

ASTM D638

39.13 MPa

Tensile Modulus

ASTM D638

497 MPa

Elongation at Break

ASTM D638

35.66%

Yield Point Elongation

ASTM D638

5.94%

Flexural Strength

ASTM D790

46.6 MPa

Flexural Modulus

ASTM D790

966 MPa

Notched IZOD

ASTM D256

364.2 J/m

Shrinkage

0.2-0.7%

Shore Hardness

ASTM D2240

85 D

Viscosity

ASTM D445

250-550 MPa*s

Density

ASTM D792

1.05-1.13 g/cm3

Range of Wavelength

385-410 nm

HDT @0.45MPa

ASTM D648-18

70 degrees C

Look/Feel/Finish

Below you will see pictures of the Rigid Resin fresh out of the printer before and after its post
processing stage. There are various finishing methods you can apply to the surface including
wet sanding, painting or glossing. By default we remove the supports and sand away the
marks (included in the price), however sometimes surfaces within pockets or odd crevices are not accessible enough to be sanded (in a time/cost efficient manner), so will be left unsanded.

The surface is naturally smooth but a light sanding then ideally a wet sand buffs away even the smallest of blemishes leaving it looking just like a commercially molded part. To do this yourself all you need is high grit sand paper (200+ grit). If the part has many fine details wetsanding may not be a option (it would buff out the detailing). The smooth surface is partially due to its layer height (only 0.05mm which as thinner than paper). At the bottom image you can see how the surface compares to our cheaper FDM printing which prints at 0.2mm layer height by default. Its worth noting that layer thickness isn’t the only factor effecting surface finish, the type of printing technology also plays a signicant role.