We are experiencing difficulty in effecting a clean removal of wooden inserts from wall and floor slabs, despite careful oiling and the use of tapered multi-piece blocks. Can you suggest a way around this?
Removal of inserts is often difficult for three reasons: natural adhesion of the concrete, lateral pressure from the hardened concrete, and swelling of the wood due to wetting. A very simple solution is to wrap the block in polyethylene film. This provides an effective separator and prevents swelling.