Dick had a strangely agricultural gun with a fairly primitive flint lock that he wanted derusted –
Its a strange agricultural looking gun with a very long barrel and what looks like a home made stock – the leather bands were the attachment points for a sling – they are the best made bits ot the gun – not sure why anyone would want to restore it, but there is no accounting for taste!
As found – heavy rust caking the mechanism and screws and action seized
After electrolytic derusting – some clean metal visible, frizzen free. I popped it in the Aga for an hour as a precaution against hydrogen embrittlement, although I think it very unlikely in this old metal..
After fine wire wheel – a good soak in WD 40 or thin oil plus a low viscosity solvent and it will all come apart and clean up…. about 10 minutes work so far. Notice it is still cocked – I need to let down the spring before proceeding.
I’ve now disassembled the lock – it turned out that the sear spring was broken and held together by rust – all the screws came out without marking the heads, but I sheared off a bit of the blade of my wide fine slot screwdriver and had to re-grind it. A couple of tips – the normal easing oils do not pernetrate as well as they might and I give parts a squirt of gun oil followed by a squirt of gun cleaner or acetone or some other volatile liquid that will carry the oil into the thread, also when you come to unscrew a screw that has an exposed end its worth having a go at screwing it in a fraction along with unscrewing it, as they often have a bit of rust or a burr stopping them backing out . Having got everything apart I wired all the bits with holes in them together with iron wire and put them back in the derusting bath to clear the hidden surfaces….
The bundle of bits being electrolytically derusted to clean hidden surfaces – see Beginners’ Guide No 2
Replacement shaft for tumbler turned and the tumbler held with setting wax and drilled out to receive it. The cock shaft has a 4 B.A. thread tapped in it – I use mostly use UNF but Dick prefers B.A. and he will probably finish the job.
I TIG welded the apex of the sear spring (it works!) and temporarily fitted the tumbler bits – it now needs the square cut for a cock and once the alignment is sorted the shaft needs silver soldering in position in the tumbler. You’ll notice that there is a lot of clearance in the tumbler hole in the bridle – I have learnt the hard way that its best to copy the original clearance- if you try to make it a close fit the alignment of the lock plate hole and the bridle hole may not be perfect and it may jam – its particularly true on poor quality lock s like this one.