Thanks for you comments oldlock.
I believe the sliding shield plate was just held in position sandwhich between the lock and the back door plate without any screw fixings. Me and my local locksmith friend Geoff Tulley have worked out that this sliding shield would have been gravity droped once the combination dial turnt back to the star. But not 100% sure yet.
from your comments it will be quite a job to find someone with the same lock for me to obtain a pattern from to make this part? but dont think it will be too much of a problem without seeing another lock but it would be nice.
you are correct, the safe I believe to be one of the smallest safes made by Chatwood. it stands just over 2 ft high. Photo attached for your interest.
thanks
Steve
