Material guide
Gluing Cast iron
Cast iron cookware, machine bases, guttering and architectural ironwork.
Also called cast.
How Cast iron behaves when you bond it
The rough, slightly porous cast surface gives excellent mechanical key once clean. Older cast iron is often oil-soaked, and that oil comes back to the surface after cleaning unless the part is heated.
Cast iron is a rigid ferrous alloy whose as-cast roughness can provide excellent key, but graphite, rust, machining coolant and absorbed oil can form weak boundary layers. Old components may re-bleed oil after an initial cleaning.
Material properties
- Surface energy
- High, which helps adhesion
- Porosity
- Semi-porous
- Rigidity
- Rigid
- Maximum service temperature
- 200C
- Normally needs abrading
- Yes
- Normally needs a primer
- No
Surface preparation
Remove rust, scale, paint and oil to sound metal by blasting, grinding or abrasion, then solvent-clean and dry. Heat-and-reclean only when the part and process safely allow it. Bond promptly before new corrosion forms, and use a gap-filling toughened adhesive on irregular cast faces.
Which adhesives work on Cast iron
Excellent
Epoxy putty
Epoxy putty is rated excellent for this material as an application-level assessment, not as a blanket manufacturer claim. The prepared surface must be sound and consistently keyed where the finish permits. Suitability still depends on the other substrate, joint design and service environment.
Abrade the surface first.
Excellent
Two-part epoxy
Two-part epoxy is rated excellent for this material as an application-level assessment, not as a blanket manufacturer claim. The prepared surface must be sound and consistently keyed where the finish permits. Suitability still depends on the other substrate, joint design and service environment.
Abrade the surface first.
Good
Structural acrylic
Structural acrylic is rated good for this material as an application-level assessment, not as a blanket manufacturer claim. The prepared surface must be sound and consistently keyed where the finish permits. Suitability still depends on the other substrate, joint design and service environment.
Abrade the surface first.
Bonding Cast iron to something else
Cast iron to Cast iron
Cast iron to EPS (polystyrene foam)
Cast iron to Polyurethane foam
Cast iron to XPS foam board
Cast iron to Cork
Cast iron to EVA foam
Last reviewed 8 October 2026.