Thanks for the tips. Will check out the Garage folks. As none of this will contact potable water or coffee, silver solder is probably unnecessary anyway. About the only non rosin core solder I could find is for stained glass work, which would seem a likely candidate. - http://www.ebay.com/itm/1-Lb-60-40-Avri ... XQVERSvwEX

leozava wrote:have you tried going to a heatingredients and cooling place and getting Flux coated brazing rod?? it requires a bit more heat than solder but also isn't as "runny"

If a MAP torch would work, might be worth a try.

Any solder that melts under 700F or so will not stand up to any load and I would expect it would just wear away on an application like that shaft. Long ago, 95% tin, 5% silver was the strongest soft solder available, don't know what's changed since then. Past that you went to silver solder. I think brass brazing rod requires oxygen, but since I always had oxygen there was no point to trying without it.

Ira

cuppajoe wrote:If a MAP torch would work, might be worth a try.

map gas should work just fine. make sure the brazing rod is wrapped in flux

I would get a replacement rod machined. The gas velocity of MAP is so high the any brass rod will just blow out of those divots. A jewelers Oxy/Acet torch would work as you can get a low gas velocity 6300F flame which will do the job.

Low temp solder will work on the group but the rod should be replaced.

The dings on the group look like they will buff out. I was doing the same thing earlier and took some videos, I will try and put that up somewhere, bear with me while I edit and upload - it's not my thing at all.

For filler material it depends on your chrome plater. The 2 companies I use for plating prefer silver solder for repairs, I have used lead and lead free solders before with poor results, the platers buff them away and you are left with a mess. I think Pascal sometimes has success with lead as a filler, so it depends on the plating company.

Here are some dents in a vintage faema portafilter that I "buffed away".



1st stage is an abrasive wheel.



Then with buffing compounds.



This other portafilter has far too much material missing, especially around the ear. You can also see a split in the metal, so this was repaired with silver solder.



And after adding the silver.



And there was a repair done to the top rim on the inside as well.



I will clean these up tomorrow, and then do as I did with the first portafilter, sanding wheel then buffing. I will also have to restore the ear profile as well, probably on the lathe.

Thanks for the tips Paul. Will try and do most of the repairs by sanding/polishing. I also plan on taking some parts in that I roughed in to see what the plater says the copper will fill. My main concern was the group, as I don't want to change the shape. Will have to learn soldering skills sooner or later, so might as well be now.

I've started collecting various solders and will see what works best, starting with silver. Can you point me to any good tutorials on doing the sort of soldering as shown in your post?

Paul_Pratt wrote:I think Pascal sometimes has success with lead as a filler, so it depends on the plating company.

I had to use lead free solder a few times when high temp brazing was impossible. On a front plate angle for example, I remember a crack on a Zenith express for a friend.


This is not easy to do and we can well see it is not perfect, more again on a picture. I had welded a copper thread behind and filled with solder on the visible side.




Zooming on the picture shows that part of soldering has been removed during chroming steps, but picture exaggerates the defects, it was a very good result in reality.

Nice work Pascal. Did you use a silver solder on that repair and still had chroming difficulties? Copper plating before chrome or nickel is SOP here, same in France?