Cast aluminum sign

I am working on a cast aluminium (or aluminium alloy) sign which has
been broken into several pieces. I have been asked to reassemble the
sign but the pieces do not fit together properly. This is partly
because some of the pieces are slightly bent and partly because I
have not been able to remove all of the corrosion products from the
rough surface of the break edges.

I would be interested to know of any techniques used to remove
aluminium corrosion and what adhesives might be suitable for
reassembling the sign. Because the metal is only 5mm thick I am
thinking of putting the pieces on a backing support rather than
simply adhering the joins which I do not think will be strong enough
and so I would also like to hear from anyone who has tried this
technique on a cast metal artefact.

Sebastian Foxley
Object Conservator
Wiltshire Council
Wiltshire and Swindon History Centre
Cocklebury Road
Chippenham
Wiltshire UK


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                  Conservation DistList Instance 23:27
                Distributed: Thursday, January 28, 2010
                       Message Id: cdl-23-27-013
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