doublegunshop.com - home Forums General Discussion DIY Gunsmithing @ doublegunshop.com Best flux for partial barrel rib re solder?

I would be very careful using anything but a Rosin flux. Rosin will work fine if things are clean enough. Other commonly available fluxes may perform better but they are not used in a repair application because they are very corrosive and can not be neutralized. Both Zinc Chloride and Ammonium Chloride are highly corrosive and any flux containing them would be a poor choice for rib repair. You could use an acid flux for tinning ahead of time then scrub the excess flux and neutralize.

https://www.oatey.com/ASSETS/DOCUMENTS/ITEMS/EN/No_95_Tinning_Flux.pdf

Thanks Steve that is also good to know.

Good advice for confining fluxes like the Oatey 95 to only jobs where the joint can be flushed and neutralized after tinning. Thanks for the pdf containing the chemical composition.

Thanks all for your help. I have the rosin flux and small rosebud for my oxy acetylene torch on orderand will report back when work is complete.

I would not use Oxy-acetylene.....way too much heat. Just acetylene, propane or map gas will give you the control you need. If you burn the rosin flux then you have a real problem on your hands and will need to pull the ribs completely and clean the area. The trick to using rosin flux and 50/50 is to work within the small temperature window between where solder flows on the low end and where flux burns on the high end. If you keep your work within those parameters it will go just fine. Too much heat is your enemy in this application.

I again thank those with information and encouragement. I nixed the rosebud order and was going to use the map gas torch after practicing on the old barrel. Then a good friend saw my post, he told and sent pictures of partial re soldered ribs he did with success on a fox barrel. Church bell rings and picts show very little solder clean up. My barrel is going to the fox man.

Just a question from ignorance.
Why is 50/50 solder used for ribs??
60/40 solder melts at a lower temperature and just as strong.
Maybe 50/50 is traditional and want the new solder to flow with the old.
Chuck