How to repair a brass door knocker???

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Hi all,I had a neighbor walk in and ask me to repair a brass door knocker.  It is made in Italy and assume its brass, could be bronze, etc.  The only thing that comes to mind is to solder it as I have never welded any of the copper / brass alloys, only soldered them.  Would a good silver solder be good enough?  Any thoughts?Thanks,Tony
Reply:JB weld on the back side and call it goodExpert Garage Hack....https://www.facebook.com/steven.webber.948
Reply:I'd silver solder it.  Brass melting point is just about 940c, Stay-Silv 6 is liquid at just around 724c so it's do-able.  Biggest issue for me would be the thickness of the brass.  Being so thin, I'd have a hard time running that temperature edge without going over and melting the brass.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:You could tig braze if you have a tig welder. If you epoxy it you'll wanna clean it real good with a sand blaster then be should to wipe it down with acetone before applying epoxy, a ruff finish will help it stick
Reply:Originally Posted by 7A749JB weld on the back side and call it good
Reply:Only thing that comes to mind Last edited by MinnesotaDave; 05-26-2015 at 03:51 PM.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Good luck.  I completed a repaired of a brass bell last year.  I use tig with sil-bronze.  Reg. Bronze was too yellow.  Repair looked good when all was shiney.  As it oxidized there was major contrast.  Being cast I was also chasing cracks that became exposed as it oxidized.  I worked on the bell off and on for two years.JB weld. Especially if it is a favor.
Reply:Dave, I like the way you think.....twisted
Reply:Originally Posted by vwguy3Dave, I like the way you think.....twisted
Reply:Originally Posted by MinnesotaDaveTried being normal once, didn't take...I think it was a Tuesday...
Reply:Silver braze it use 15% or higher silver content.  I prefer 50N for all of my more difficult repairs.
Reply:I have repaired one that was similar.  Not the only way and maybe not the best but it is holding up as far as I know.wire brush the inside around the break and then build a "dam" out of cardboard or something just up from where the deeper depression stops and it has that flat.  figure out a way to clamp and hold the broken piece to the main body and then fill the whole cavity/broken piece with a slow cure epoxy.the epoxy will take the structural load of the attachment point and the crack will not matter and should be invisible.  no worries about ruining the patina.not welding but it will fix it.
Reply:Hi all, thanks for all the suggestions.  I decided to silver solder it.  I called the welding supply and they're looking at $60 plus for a troy ounce of silver solder (plus the flux).  Plus the stuff has a melting temperature of 1300 degrees.  I opted to go to the local ACE hardware store and pick up some silver solder (8,000 PSI tensile strength).  The first attempt soldered real good and the solder barely poked through to the visible side of the joint.  I fit it using one of those little "helping hands" type device that has two alligator clips (with infinite adjustment) to fit the broken part like a jig saw puzzle.However when it broke, the metal deformed such that when lining up the pieces exactly actually had the broken part out of line with the rest of the door knocker and was angled up after soldering when looking at it from the side.  So I laid it flat on my table and melted the soldered joint so that the solder relaxed and rested on the table making the whole part in line again.  This left a very slight raised joint making it necessary to fill it in with solder forming a tiny fillet which is visible from the top side.The repair is only visible to those of us who notice those things and compulsive nit pickers.  A good compromise if you ask me.Thanks again.Tony
Reply:Good job.  And if you are worried about strength, pot the back side with epoxy."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder