The helmet was treated by Andy Thackeray, an intern in Furniture Conservation. He describes his treatment below.
– Cracked and lifting lacquer on the iron substrate rim of the helmet bowl, and where lifting from the iron supporting bars of the neck plates (ita jikoro), were consolidated with an application of xylene followed by a 10% solution of Paraloid B48N in xylene. If moving they were clamped either by lightweight clamps or using a shimbari system. Cracked and lifting lacquer on the leather substrate of the ita jikoro plates was consolidated with 10% and where appropriate, 20% Mowilith 50 in toluene.
– Peeling vellum/leather was readhered by coating the metalwork below using 20% B48N in xylene. Once the solvent had evaporated, the material was laid flat and heat sealed using a heated spatula to 60 deg celcius.
– Tests to remove the corrosion products from the replacement ‘wakidate’ by scraping lightly with a mother of pearl spatula, were unsuccessful at uncovering a similar patinated finish as the rest of the ironwork. Abrasion removed the corrosion but went back to the bare metal. Perhaps the colour of the patination never quite matched. Only corrosion products were removed from the rest of the ‘wakidate’.
– Mechanical attempts were made to remove the lead solder but endangered the surrounding patinated metal. The surrounding metalwork was isolated with 20% B72 in xylene and ‘West System G-Flex’ thickened epoxy resin was used to readhere clasp. The barrier was removed with xylene. The exposed solder was retouched with ‘Gamblin colours’ in xylene.
– The loose front clasp held in position (tilted forward). A soft wedge was made from saturating a black stained (Golden Airbrush colours) piece of acid-free card in Paraloid B48N. This was pushed into the open gap between clasp and helment using a spatula. Excess was trimmed with a scalpel and the B48N reactivated with xylene. The clasp was released to self clamp the material in place.