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Several posters complain that I don't post photos of my work. Most of the stuff I do is in mild steel, SS, and aluminum and there are plenty of "great" weld photos posted of those materials.One thing I haven't seen much discussed here is welding/repair of copper based alloys. Silicon bronze being one of them.Last summer one of our customers hit a log with his 50' flushdeck motoryacht. Bent the shaft, propeller, and rudder shaft (SS). Additionally, which wasn't apparent til we got everything torn down was that he had also broke the bronze rudder support post/column. This is the part that supports the rudder with a bearing pressed into the top and a sealing ring which mounts at the bottom. There's also an upper support above the rudder post.The boat was built in Asia nearly 18 years ago. Took a bit of effort to get thru to the manufacturer. That resulted in a dead end. Said the molds for the rudder post had been lost/destroyed years ago and they no longer produced that part. Their new boats used a completely different setup. (After studying the design, I can see why.)The next call was to Buck-Algonquin who produces much of the marine hardware used in the trade. They were "very helpful" but didn't offer a viable solution. They would need the broken part in order to build a form which they would use to build a new mold. Process would take about 3 months and a new rudder post would be about $1,800.That's when the yard owner called me. I've done some bronze repairs for him in the past and they turned out pretty good.The first photo shows the rudder post in two pieces. This was after the parts had been cleaned and prepped. As soon as I put a tig arc on the base, I knew it was going to be a problem. The "junk" that came up out of that casting was something else. Kept looking for a dog paw to pop up. Stopped what I was doing and picked up the phone and called a buddy who runs a local fab shop. Asked him if he knew anything about welding cast bronze. His reply was he knew enough about it to stay the heck away from it. No help.Started buttering the base member (larger of the two parts shown in the 1st photo). After about three rounds of laying down a base and grinding it out, I thought I had it cleaned up enough to start welding. Placed the tubular part on the base (all the photos show the part inverted from the way it goes into the boat), tacked it well. Put the piece on the positioner and ran a bead all the way around. As the part cooled, a crack formed all the way around the bead (center of the bead). OK. First lesson. Gonna need preheat.The problem with the way the part was designed was that the weak point was the flat piece where the tube meets the base. Where the part broke is only about an 1/8" thick and the rest of the base is extremely heavy (some places more than 1" thick). Additionally the walls of the tube are about 1/4" thick. I also noted that, in addition to the crack in the weld, the part had "pulled" slightly even though it had been well tacked.At that time I decided I had to have a jig to support the part for welding. Had a piece of heavy wall pipe that was just a shade larger than the ID of the tube. No problem. Machinist buddy of mine turned it down to the exact ID of the tube in short order. I then welded that vertical to a piece of 1/2" plate. Now I've got my jig.Broke the vertical member out of the base and "reprepped" both pieces. Most of the prep had to be done with a hand grinder and a carbide burr. The second photo shows the two parts prepped for preheating and welding.Next the parts went on the ol propane stove and were preheated to 400 deg F. (used 400 deg and 350 deg temsticks to check temp along with a temp gun). Photo 3 shows the part on the propane stove.Once the parts reached preheat temp, they were placed on the jig and clamped down. Then on to the positioner. The weld bead in the photo looks "beat up" because it is. For this phase of welding what I did was weld hot for about an inch around the perimeter. Then peened the heck out of the bead. Rotated the part and did the same thing on the opposite side. Part had to be taken back to the stove three times to maintain the heat. Finally completed the weld. Put the part in a bucket of sand and let it cool there overnight. Photo 4 shows the part at this stage. Beat the heck out of it with a dead blow hammer and the weld held.At this point the yard manager wanted to just reinstall the support as is. The more I thought about it, the more convinced I was that I could improve on the original design. The weak point was still that 1/8" surface the tube was welded to. He agreed to give me "a little more time" to work it out.Went back to my machinist buddy to have him cut the shoulder of the weld down so I could put a sleeve on the vertical tube. We tried with both the lathe and mill but the original casting was so "untrue" we couldn't get anything to work. Back to the positioner and the die grinder with the carbide burr. Put a nice taper on the weld bead between the base and the tube. Then took a discarded cutlass bearing (bronze bearing that supports the propeller shaft) and cut a notch in it so I could slightly reduce the ID. Took out enough material so that, when clamped to the vertical tube, I had a good tight fit. Again preheated the whole assembly. Put it back on the jig, and welded the sleeve with a perimeter weld around the base and at the top of the tube. Tacked the seam. Took the clamps off and welded the seam. Back in the sand bucket. Next AM a yard worker was waiting for me when I got to the shop. Took the part right back to the marina and the boat went in the water that afternoon.Charged the marina $600 for the job (less than 24" of actual weld bead). Owner was "thrilled". Had his boat back now (not 3 months later) and cost him 1/3 what a new part would have cost.Didn't take photos of the "second stage" of the repair because, quite frankly, I was more concerned about getting the job done than I was taking photos.Learned a lot doing this repair. Silicon bronze, even though not quite as strong as aluminum bronze filler was a better fit for this repair. Asian bronze has a lot more impurities than US bronze castings. Preheat is absolutely necessary.One of the more challenging repairs I've encountered. Attached ImagesSyncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Looks good Sundown.I know what a pain in the arse it is to weld. I had to build up a fork for a dog clutch on a friends boat. One ear was gone and the other needed minor build up. Looking for the pics. I'm sure ive got at least after shots.
Reply:Neat repair, thanks for sharing.
Reply:I love SiB for headers and have had good luck with it in other small bronze repairs ( windshield frames for custom cars namely ) once you get the hang of it it, it really is good stuff. Never had occasion to use it on any larger repair jobs like this but it was a well written piece, thanks for taking the time to walk us through it. "Anybody can talk $h!t behind a monitor, I let the quality of my work speak for itself"Lincoln Square Wave 255 and 355 Tig Lincoln 255 Power-Mig w/ spool gun Koike 5 x 10 CNC plasma Hyd-Mech DM-10 bandsaw Ineco QB-76 NC tube bender
Reply:That oughta shut 'em up.....Outstanding work sir.
Reply:nevermind, reread the post
Reply:SundownIII,good job with the SiB. I was wondering if you have tried SiB on aluminized and what your take was on the process? Did you like it or do you feel it is an adequate filler metal? I used to weld aluminized with SiB but have gone back to er70 because i just didn't like how it flowed. I have even tried it on AC settings which is a whole different process.Thanks,JoshMiller Dynasty 200Millermatic 211Instagram?.... find me @ WELD_MEDIC
Reply:Nice welding sundown! Now if only if life had a happy pill for your grumpy a$$, you might become a functional person in society!
Reply:Very cool. Couple questions: In the first pic, is the dimply surface of the base piece how it looked after being just cleaned(wire cup?) or after being welded/built up? Second, would beating the part as you weld, say with a raw hide mallet help prevent cracks? Thinking like cast iron. Or is the cracking just straight forward cooling to quickly?With the cost of specialty parts like this and getting replacements, it seems you could make a nice side business specializing in just repairing boat bronze.B200amp Air Liquide MIG, Hypertherm Plasma, Harris torches, Optrel helmet, Makita angle grinders, Pre-China Delta chop saw and belt sander, Miller leathers, shop made jigs etc, North- welders backpack.
Reply:tig_21,Haven't used silicon bronze filler on aluminumized steel. If you decide to try it, you may want to look at the aluminum bronze filler. Actually the aluminum bronze filler has a little higher tensile strength than the silicon bronze filler.If you read the literature (Lincoln Procedures Handbook), it states that silicon bronze can be welded with DC (or AC). When buttering the base in prep for final welding, I actually used AC with a high frequency pulse and balance set to about 70%. Seemed to agitate the puddle and bring the impurities to the surface. For the final weld, I turned the pulser off and left the balance at 70.Having welded a fair amount of bronze from different sources, I can state that there is a difference in the quality of the materials used in the casting process. Even after all the prep, this part was still "very dirty" to weld. Lots of soot. Lots of SS wire brushing between beads. Also interesting to note is how the part changed color with preheat. Went from a true bronze to an almost gold color. This color change was just on the surface. If you hit it with a scotchbrite pad on a die grinder, the original color comes right back.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Ah, TIG was used. I missed that mention in the first post and wasn't quite sure what process you were using.Interesting. Question: Any reason you just didn't 'make' a new assembly instead of trying to weld the (crappy) original back together? Take 'marine' alloy of desired type, machine to fit bearing and seal, attach to rectangular base-plate (or possibly re-use the OEM one)? Or was it a matter of you already had the 'materials' in the form of the OEM stuff, and didn't quite realize just how 'crappy' the metal was until you got into it? Just wondering. The best laid schemes ... Gang oft agley ...
Reply:Thanks I'll have to definitely try the aluminum bronze filler. In the picture i show aluminized pipe welded on AC and DC with SiB. This is why i don't use this filler anymore because the consistency is so hard to get with it. AC cleans and makes it look nice and shiny but it is not what I am looking for in a high quality aesthetic weld. DC turns out dull unless sanded then is becomes more like the weld done with AC. Sorry I don't mean to stray from your project just thought I'd share.... Thanks,Josh Attached ImagesMiller Dynasty 200Millermatic 211Instagram?.... find me @ WELD_MEDIC
Reply:I am interested in seeing SD's aluminum and steel welds!Miller Diversion 180Hobart Handler 140 (Soon to be replaced with Miller 211?)Miller Spectrum 625 Extreme
Reply:Give it a rest Jon K.Im sure is speak for most. Im getting sick of you butting into threads asking for the same BS.If you dont like it here, find some other forum to post your BS on.
Reply:Mick and Larry, I agree with you. Sundown doesn't need us to defend him, but I sure would be glad to have him with me on LRRP.Jon, you have made your point and now you're starting to make yourself look bad. He has posted some great pictures, which I have enjoyed seeing, so maybe we should thank you for that.I think Sundown is smart enough to follow one of my favorite expressions: "Never argue with an idiot. They drag you down to their level, then beat you with experience".Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Sundown did you preheat it before you welded it ? I'm asking because it looks like its sitting on one of those colman camping grills.Will Supports Autism Awareness My ToysBobCat 225 PLusMillermatic 130Miller Spectrum 300 CutmateEverlast Power Tig 185 Micro April is Autism Month .
Reply:Originally Posted by SteelwillSundown did you preheat it before you welded it ? I'm asking because it looks like its sitting on one of those colman camping grills.
Reply:Originally Posted by DSWThat's what the man said...Nice job there. Never had any call to do any bronze yet. I'll have to keep my eyes open for a chunk I can play with at some point. Never stop learning new things...
Reply:I have done some repairs on bronze that marinated in salt water. Castings are always of questionable content (like the "dog paw" SD was talking about). But soak it in that electrolytic solution and it just gets weirder! Anytime it has that pink tint to it, or has just the pink spots in it, no telling what it will do when heated.Nice job Sundown, thanks for posting!-IanMiller Dynasty 350Miller XMT 304
Reply:Looks good sundown. I haven't dealt with many bronze pieces but the ones I have always seem to have stuff continually leaking out of them as you weld. I always treat them like cast iron and cook them several times to try and clean them up just like you did. I like to see these odd projects on here from time to time.Millermatic 252Lincoln 175 plusTA 185tswTA 161stlhypertherm pmax 45Victor torchHenrob torchAn S10 for each day of the week |
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发表于 2021-8-31 23:23:55