I use liquid rosin flux, Kester 1544.

https://www.newark.com/kester-solde...Nk2LM9PHMI21SDybiBMHDSGRrzhoCkqcQAvD_BwE

When tinning I let the soldering iron do most of the work and use a torch sparingly, mostly toward the breech end. I try to heat ahead of the area I am tinning with the torch and keep the flame away from the flux. I made up some soldering coppers to fit inside the bore as well, turned on the lathe slightly under bore diameter and mounted on a rod, they can be heated with a oxy acetylene torch then inserted to where you need the heat.

It has already been mentioned that cleanliness is key to success, I have found that a media blast cabinet is an excellent way to prepare the surface under the ribs for tinning, especially if any corrosion has taken place in the past. I use fine glass beads or my blasting media.

Last edited by SKB; 03/27/26 09:33 AM.
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