Straightforward
How to glue ABS to ASA
The short answer
Bond ABS to ASA with a one-part MS polymer / hybrid adhesive-sealant (silane-terminated polymer) rather than an ABS-specific solvent cement. Manufacturer data for products such as Sikaflex-521 UV explicitly lists ABS as a bonded substrate and rates the cured joint 'ageing and weathering-resistant', which matters because ASA is specifically chosen for outdoor UV exposure. A two-part methacrylate (structural acrylic) or two-part epoxy gives a stronger, more rigid joint indoors where long-term colour retention under UV is not the priority; cyanoacrylate can tack small areas quickly but is not the primary recommendation for a full joint. Never rely on an ABS-formulated solvent cement for this pair: SCIGRIP's own datasheet for its ABS solvent cement states it is formulated for bonding ABS to itself only, and ASA's different rubber phase means it is not a validated solvent-weld partner for ABS.
Why this bond behaves the way it does
ABS and ASA share the same styrene-acrylonitrile (SAN) backbone and similar surface energy and rigidity, which is why generic structural adhesives that don't rely on solvent interdiffusion (MS polymer, methacrylate, epoxy, cyanoacrylate) bond both sides reliably. They differ in the rubber phase: ABS uses polybutadiene, which is UV-sensitive, while ASA uses an acrylate elastomer, which is exactly why manufacturers choose ASA for outdoor parts. That same chemical difference is the likely reason ABS-specific solvent cements, which work by partially dissolving and fusing two ABS surfaces together, are restricted by their own manufacturer to ABS-to-itself rather than extended to ASA.
What to use
Best choice
MS polymer
Manufacturer TDS (Sikaflex-521 UV) explicitly lists ABS among bonded substrates and rates the joint 'ageing and weathering-resistant', which matters because ASA exists specifically for outdoor UV exposure. One-part, no mixing, moisture-cure. ASA itself is not manufacturer-named, so treat the ASA side as an assessed match on shared SAN chemistry rather than a manufacturer claim.
Curing: Moisture-cure, skin time about 30 minutes; full cure over several days depending on bead thickness.
Also works
Structural acrylic
Two independent SCIGRIP methacrylate TDS explicitly list ABS ('styrenics' thermoplastic category also covers ASA's chemistry, though ASA is not separately named). Gives a stronger, more rigid joint than MS polymer where maximum strength matters more than outdoor colour retention.
Watch out: Manufacturer TDS states UV colour stability needs a stabiliser additive (Benzoflex 2088) for prolonged outdoor exposure.
Also works
Two-part epoxy
Permabond's own ABS guidance lists two-part epoxies among the families that bond ABS. Good general-purpose rigid bond for indoor or UV-limited use; not documented as weathering-resistant in the sources reviewed, so it is a weaker outdoor choice than the MS polymer option.
Only in some cases
Cyanoacrylate
Bonds ABS per Permabond guidance and sets almost instantly, useful for tacking small areas in place before a structural adhesive is applied. Not recommended as the sole adhesive for a full joint: gap-fill range is only 0.015-0.5mm and the bond line is brittle, with no documented outdoor durability.
Avoid
Solvent cement
SCIGRIP's own ABS solvent cement TDS states the product is formulated for bonding 'ABS plastics to itself only'. ASA is a different copolymer (acrylate rather than butadiene rubber phase) and is not covered by this restriction-bound product, so an ABS-specific solvent weld is not a validated method for this mixed pair.
What to avoid
Avoid ABS-specific solvent cements (any product documented as bonding 'ABS to itself only') for this mixed pair. Avoid acetone or other aggressive solvents when cleaning either surface; use isopropanol instead, since acetone can attack both plastics. Do not rely on a generic epoxy or cyanoacrylate as the sole joint for a part that will sit in continuous sun and rain without first checking that specific product's UV/weathering claims, since neither family is documented as ageing-resistant in the sources reviewed here.
Preparing the surfaces
ABS
ABS: use clean, dry material; if wiping is needed use isopropanol rather than acetone, which can attack the plastic. Limit uncured-adhesive dwell time. No abrasion is normally required on genuine ABS for an MS polymer or methacrylate joint, but a light key on a hidden area is a reasonable precaution before committing to the visible joint.
ASA
ASA: use clean, dry material and remove any weathered, chalked or UV-degraded surface layer before bonding, since a part that has been outdoors can have a weakened surface skin. Wipe with isopropanol after a small compatibility test, and lightly abrade a hidden area if using a structural (methacrylate or epoxy) adhesive. Avoid aggressive solvents unless deliberately solvent-welding ASA to itself.
If the conditions are harder
| Condition | Verdict | Notes |
|---|---|---|
| Outdoor use | Works with care | ASA is specifically chosen for outdoor UV exposure. An ageing/weathering-resistant MS polymer such as Sikaflex-521 UV (manufacturer-rated 'ageing and weathering-resistant', lists ABS explicitly) is the better-evidenced outdoor choice than a generic epoxy or cyanoacrylate, neither of which carries a weathering claim in the sources reviewed. A methacrylate structural acrylic (e.g. SCIGRIP SG300) can also be used outdoors but its own TDS says UV colour-stability needs an additive. |
| Water and wet areas | Works | Neither plastic absorbs water. The MS polymer option is manufacturer-rated 'generally resistant to fresh water, seawater'. Cured epoxy, methacrylate and cyanoacrylate joints are also generally moisture-tolerant once fully cured, though none of the sources reviewed here documents immersion specifically for this pair. |
| Heat and cold | Works with care | The plastics are the limiting factor, not the adhesive: ABS softens from about 85-89C and ASA from about 90C (existing material profiles), both within the tested range of the adhesives assessed (MS polymer -50C to 90C continuous; methacrylate -40C to 82C). Do not exceed the plastic's own service temperature even though the adhesive itself can tolerate more. |
Products that fit
Ordered by how well they suit this specific job. Nothing is ranked by what it pays.
Sika Sikaflex-521 UV
MS polymer
Manufacturer TDS explicitly lists ABS among bonded substrates and confirms ageing/weathering and water resistance relevant to ASA's outdoor use case; confirmed for sale on Amazon UK.
We may earn a commission from links on this page. It never changes which adhesive we recommend.
Related guides
- ABS to MDF
- ABS to Plywood
- ABS to Painted metal
- ABS to Glass
- ABS to Glazed ceramic
- ABS to Stainless steel
- How to bond an ASA part to an ABS housing outdoors
Where this comes from
Reviewed 8 October 2026. Overall confidence: Strong evidence.
Sources used for this guide:
Always read the instructions and safety information supplied with the product you buy. Where they differ from anything here, follow the manufacturer.