repairing a tear in thin copper sheet metal

admin

Hi all,I just got a project doing some repair work for a client.  It involves some standard gate and fence repair (broken welds and torn hinges, etc.)  I also have to build an aluminum trash can that will fit in an under the counter drawer in a patio bbq island.  That's the easy part.  The hard one (for me) is that they have a custom built copper mail box that has a tear in the front pull down cover.  The only metal work I have ever done with copper has been to solder or silver solder the stuff.  I would like to repair this tear and try and maintain a decent color match.  With the silver solder there will be a tell tale line of silver peeking through the repaired joint.Is that about the only way to repair this type of damage?  I thought maybe I could tig it closed but am afraid of blowing holes in the process as the stuff is pretty thin (probably 18 to 20 gauge).  Anyone have any ideas?  If I did solder the joint, would the solder hold it OK as it is not in any type of overlapping type of joint but rather butted together.  Also how might I restore the dark patina in the repaired area as I will have to shine it up to do any type of welding or soldering on it?Thanks for any ideas,TonyLast edited by therrera; 04-13-2015 at 07:25 AM.Reason: To add more information
Reply:After having a copper sink all I can say is good luck on the color. I would repair it how you normally planned and let it naturally patina. It'll blend back together. What would be great though would be to polish their address numbers and spray some clear coat on them!Brett
Reply:It might pay to cut yourself a small copper L shaped patch to reinforce the back of your split. You can then do most of your cleaning and soldering in a location where it won't be quite as visible.If it's pure copper, I'd probably use regular lead solder vs silver solder. Lead oxidizes to a mat grey color pretty quick. I really don't see the need for higher strength silver here..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:The repair DSW stated sounds the best, they use to make a chemical that smelled like rotten eggs that would put the dark patina on copper, many moons ago when I was in a 4-H club we made copper projects with new shiny copper and we soaked them in the rotten egg stuff and it looked just like the mailbox color...I dont know if they make it anymore...Of all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:You can get patina in a jar you apply with a brush at any place that sells stained glass supplies..No stink no problem..Covers copper and solder.Mrs zap has a couple of jars here but that won't do you any good where you are......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by roadkillbobbThe repair DSW stated sounds the best, they use to make a chemical that smelled like rotten eggs that would put the dark patina on copper, many moons ago when I was in a 4-H club we made copper projects with new shiny copper and we soaked them in the rotten egg stuff and it looked just like the mailbox color...I dont know if they make it anymore...
Reply:It's a generic mailbox. If it were a custom box with any style it would be worthy of extensive repair and color match. Back patch with copper rivets and be done with it.Last edited by Bosco99; 04-13-2015 at 10:53 AM.
Reply:Re-read original post where it says this is a custom box. My apologies. Never mind. Good luck.Last edited by Bosco99; 04-13-2015 at 01:01 PM.
Reply:I'd soft solder a piece of copper over the inside. Probably on the opposite unbroken side too, if it looks like it might break.
Reply:If you have TIG , some deox copper and weld it up.
Reply:Thanks for the replies fellas,I have never tigged copper before but saw a youtube video on the subject.  Although they were doing 1/4" plate, it still seemed pretty straight forward.  The guy actually used a piece of copper electrical wire to weld with.  Think I can get by with some solid electrical copper wire?  This stuff is thin.  How would I go about it?  My thinking is clamp the torn area down on a shiny steel plate for backing and weld it.  However I have never welded copper, much less thin copper like this stuff.  However I like the idea because I could grind it flush and hammer it flat again so the repair should be invisible (theoretically).Any thoughts on whether to tig this or not?  My safe side says no, play it safe, solder it.  But my more daring side says to go for it.  Problem is that if I mess it up I will have a time consuming headache on my hands.Thanks,Tony
Reply:A customer project like this would NOT be a place I'd try a brand new untried process, especially on something very visible and super thin. I'd stick to solder myself..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:grab some thin copper sheeting from homedepot or another source and see how it tigs for you, then decide if you want to try on the mailbox...Of all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:I've played with a bit of copper TIG and found it fairly straightforward. You need about twice the heat you'd use for steel, and try a 1 hz pulse. Using household copper wire.You'll end up with a red oxide layer but it can be polished off.You should try it on a scrap piece, and then solder the mailbox.Sent from my iPhone using TapatalkSqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A
Reply:then oil the hinges so it dont do it again
Reply:Hi again,I think I will play it safe and solder it.  However I will get some copper and try my hand at it as sooner or later I will be down this path again.  I have an old school Hobart TR-250HF machine, 70's vintage I think.  So no programming possible.  It is what it is.Thanks,Tony
Reply:Originally Posted by therreraI have an old school Hobart TR-250HF machine, 70's vintage I think.  So no programming possible.  It is what it is.
Reply:Hi all,I gave a quote for the job to the client and he said "I'll get back to you".  That was a week ago.  My guess is he won't call so I won't hold my breath.  Regardless I picked up some copper remnants from one of the local metal suppliers so I could practice on.  I'll try tig welding it.  If I can do it without difficulty  I'll go that route.  My procedure would be to put a piece of stainless steel as a backing strip and weld the back side first, grind it down and then move the backing strip to the back and weld the front side.  Just thinking out loud.Thanks for the help,Tony
Reply:Can't believe they painted the copper black,  however if metal thieves realized it was copper it would be gone in no time.Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:its not painted, thats the patina of copper as it ages, or you can chemically darken the metal...no coating to peel off...Of all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:I have flag poles made from copper water pipe that turned dark......not quite black but very dark brown. I was waiting for the nice green color to appear.....maybe some copper doesn't turn green.
Reply:piss on it and it will turn green..lol..but trueOf all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:I'd be as red neck as I could get.....dirty overalls, no shirt, standing on the hand rail of the deck on the front of the house peeing on the flag poleOf course my neighbors would just see me and say "yup,nothing new going on at Mikes"
Reply:Hi fellas (and lurking ladies),I went out and did the job yesterday.  Turned out ok.  The client was happy.  The repair is strong but is very noticeable now.  When it tarnishes it should blend in close enough to not be noticeable  (I like to think so anyway).  I soldered it.  I made a copper backing strip, tinned it, coated the area with flux, clamped it in several places and let the solder flow!!!The patched areas are very strong.  Between the time  I went and when I was called to go and do the job, a new break occurred to the right hinge.  The problem was that there was no door stop so the mail person would open the mailbox door and let it fall. Over time the copper couldn't take the it and developed tears as shown in the picture.  The original installers had a door stop but they positioned the base (with the door stop) to the rear of the mailbox where it was doing nothing.I cut it and re positioned it on the front, under the door so it had a place to rest when opened.  In addition I welded a small rectangular pad to the stop so that the stop did not punch a hole in the door from repeated openings and dropping on the stop.  Attached are some shots of the repair.Thanks again,Tony
Reply:I'd say you did a fine job.RichNice work... The question is did you piss on it for patina
Reply:Nice looking repair. I'd say that solder was the safest bet for a customer repair like that. Better safe than sorry. It'll all blend in within a year or so sitting in the elements. It doesn't take long at all.
Reply:Thanks.  My only shortcoming I think on this project is that I was not quite able to fill in the slight gap between the parts.  The right hinge filled in nicely but the left side tear did not.  The repair is solid as the backing strip is well soldered to the broken area.  It just did not fill in all the way in parts so the line is visible.  But, "oh well........."
Reply:looks great and in a few weeks it will darken.....noone will know it was repaired..Of all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:Originally Posted by therreraThanks.  My only shortcoming I think on this project is that I was not quite able to fill in the slight gap between the parts.  The right hinge filled in nicely but the left side tear did not.  The repair is solid as the backing strip is well soldered to the broken area.  It just did not fill in all the way in parts so the line is visible.  But, "oh well........."