I need help fixing a poor weld

admin

Hi Guys, I am restoring an older car and tried to patch the frame rails. I removed the rusted section, and made a template and cut new 14 gauge steel for the patch. I installed the patch with reach over clamps, got everything nice and tight and all welding surfaces nice and bright. I set my millermatic to 3 voltage, 33 speed, and gas at about 20. Using 023 wire I made a bunch of sticth welds around the perimeter of the patch,(this is a butt weld). I then grinded the welds down. When I was finished I looked at the back of the welded area and saw that I could still see the seam from the back. So Im thinking that I did not penetrate deep enough. Now I need to fix the patch. Please dont bust on me too bad about the quality off my weld, I know its poor, but this is how im learning.After I ground the weld down I went over the area a few more times with the welder filling in holes.After I ground it down, it looks good from the front, but Im not satified. Can I set my welder to a higher setting maybe with 030 wire and do some criss-cross welds or something? Attached Images
Reply:One thing to remember - even a booger weld will hold a lot.Its always nice to weld in the down position - but not always possible.If the one side is welded, v notch the other side and put in a weld and then come back and grind down the weld on the other side and do the same thing - or blend the weld so it doesn't look rough and it should be fine.I would say that there was a lot of rust in that metal that you were welding to and the rust came out and blended with your weld.  Your wire might be a little thick for the job and the speed and the amperage.  If you crank up the amperage and put a cover weld over what you already welded - after grinding out the porosity - it should be just fine.I would start at the top and weld to the bottom - with the wire as close to the tip as possible and the tip extended out as far as possible and if there was any breeze - put up some cardboard around where you are welding to keep your shield gas from blowing away.I would say that you were starting and stopping too much and that you were trying to cover too much all in one pass.If you see that you are blowing out - stop and stitch it in with slow dabs of the wire.  If the metal is hot - it will blend in easier then just pulling the trigger and hoping for the best.Keep Welding!
Reply:Originally Posted by chrisd6875 Please dont bust on me too bad about the quality off my weld, I know its poor, but this is how im learning.
Reply:Thanks, Millermatic 130. 110v.
Reply:Originally Posted by DSWSorry. You're going to get it anyways. Structural parts like frames are poor "learning" projects. I don't know how "old" older is, but many vehicles past the mid 70's use special steels and they require special weld techniques well beyond that of the average welder, let alone someone learning. Learn on something else and THEN do things that are critical. While it's true "poor" welds may hold alot, I wouldn't bet my life and the lives of others on a poor job. How'd you like it if I killed someone you love because I didn't want to do it right?I'm off the soap box now...Not knowing the model Miller you have the settings don't mean much. Those settings on a MM 140 will not get you the same things those settings will on my MM185. A 110v machine is not really the best choice since you are running near max on this, but a 220v machine would do this easily. "stitch" welds are a poor way to do a frame, and from the looks I wouldn't even call them stich welds. More just on and off the trigger. Great for body work, but not for a frame. Done right you should beable to see the weld clearly above the surface of the back side. Not super far, but past the original surface.More weld is usually not the way to go. You put more heat in and adversly affect the Heat Affected Zone (HAZ). In your case all you did was make more cold laps. Every start/stop is a new place for cracks to start from. (The reason "spot" welds like you did are not for frames. Mig starts are often cold and penetrate poorly. There are any number of ways to prevent/limit this, but not having 50 start/stops is a big one.As far as wire size, you can do that with .023, .030 or .035 depending on your machine, how you set it and your technique. The guys at the tech school do all their basic work class work in all positions with .035 on 11g (1/8") 14ga is certainly do able with any of the combos.I'd suggest you cut it all out and start over. Cut outside the welds to remove the HAZ of what you did. Grab a bunch of 14ga plates and set them up in the position you will have to weld. IE stand them vertical, then lay on the floor and weld, just like you will on the vehicle. Do this until you can get 100% penetration every time say 1/2 dozen times in a row, and the welds look good from both sides. If you haven't already, I'd suggest you look into a good mig class at a local tech school or CC. The money you spend will go along ways to getting you where you want fast. When you look at what you get after you figure in materials, wire, gas, electric and instruction, the class is usually stupid cheap.
Reply:Miller doesn't list the weld settings in the MM130 manual, but they do for the MM130XP, the closest I could find that matches your unit.For 14ga, they recommend heat of 3 and wire feed of 50 with .023, heat of 3 and wire feed of 45 with .030 with CO2. Heat 3 and 60 for both wire sizes with 75/25.  For this I'd be tempted to do test runs on heat 4 wire at 55 or 50 respectively ( 11ga settings CO2) or  4 and 75 or 4 and 65 (75/25) to be sure I had enough heat to do this right. You're also going to want to be sure your outlet is up to snuff so you are getting all the power the machine wants, and the output isn't reduced due to low input. You should be able to run all of this in 2-4 welds. Don't stop at the corners either. Wrap around the corners so your start/stops are in the straight run by at least an inch or so.It's tempting to run slower wire and colder when running out of position, especially if you don't do this well. The problem is mig has a tendency towards making "pretty" welds that have no penetration. ( Especially true with small 110v machines like the MM130)  You need to crank up the wire speed to increase the amps you are running to have the heat to do this right.Also I forgot to mention earlier, for something like this, a fish plate over the patch would probably be a good idea. This would help to stiffen and support the patch. I'd probably be tempted to gap the patch  (1/8"- 5/32") and put the fish plate on 1st. Then I'd burn the gap in welding the patch, fish plate and original materials together all at the same time. this would allow you to run hotter as you won't be doing an open joint, but lap welds that are easier to run. The fish plate should be  shaped with the corners rounded. This will help limit stresses and cracking.Last edited by DSW; 10-16-2010 at 12:18 AM..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:Originally Posted by DSWAs far as wire size, you can do that with .023, .030 or .035 depending on your machine, how you set it and your technique. The guys at the tech school do all their basic work class work in all positions with .035 on 11g (1/8") 14ga is certainly do able with any of the combos.
Reply:Good tips so far. When I want a 100% penetration butt joint on gauge steel, fit up is absolutely critical. The gap should be about 3/32" and absolutely parallel all the way around. Tacks should be feathered with a sanding disc and clean of smoke, silica deposits, rust, etc. With the machine set up with the voltage and wire just right, the weld can be made continuous, no side to side manipulation is needed. Just weld straight ahead. The root-face should look like a mini-version of the bead-face, smooth with an even heat signature. Does that make sense? This is just an odd example and could be better, but the end result is close to what I was looking for. Your opinions may vary.  Attached ImagesLast edited by tanglediver; 10-16-2010 at 12:29 AM.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:I wasn't going to reply to this, but I feel I should say this...Not trying to be mean or anything, but...Take this project someone who actually knows how to weld and have them grind out your mess and re weld it.  Practice on something else.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Hey chrisd,My response is also not to sound demeaning or crude. The beginning of your first sentence: "I am restoring an older car"  is not reality. Your feeble attempt is going to get you into serious trouble until you fully understand the parameters of doing any kind of repair on a frame.So you understand my response, I do 4-6 classic car resto's a year from the frame up. These cars are fully examined by me, all the potential problems discussed with the owners, the stages of restoration/material replacement understood so the vehicle is truly roadworthy. I NEVER weld on rusted metal..... it's not gonna work..... never has & never will. If I determine a person wants to go "cheap" with material/shortcuts/quality, I turn down the job. Half-a$$ed work is no way to protect your work standard/ethic & promote future work. You also have to understand that the fellows I work for are ready to spend considerable $$$ to make their classic absolutely primo. They do not cut corners or settle for mediocrity. All the jobs I get & do come from recommendations from satisfied customers. You will be amazed how fast the word gets out on "hack" jobs & those who do it.First, you need to get a dictionary & look up the words: "restore" & "restoration" to get a grasp on what is entailed starting a project like this. Next, I strongly suggest you take DR33's advice if that is the depth of your welding ability. It takes years to be proficient working with car/truck panels & the issues with any rusting. JMO......take it with a grain of salt......DennyComplete Welding/Machine/Fab. ShopMobile UnitFinally retired*Moderator*"A man's word is his honor...without honor there is nothing.""Words are like bullets.... Once they leave your muzzle, you cannot get them back."
Reply:Originally Posted by DesertRider33I wasn't going to reply to this, but I feel I should say this...Not trying to be mean or anything, but...Take this project someone who actually knows how to weld and have them grind out your mess and re weld it.  Practice on something else.
Reply:If I may add...Generally, patch work type repairs can benefit form "backing plates" for butt joints welded from one side. If you have access to both sides, you can usually weld from both sides. However; on thin sheet metal, you should be getting full penetration from one side if the wire size and machine settings are properly matched to the application. You can use dissimilar metals (aluminum backing when welding steel for example) for temporary backing just to support the puddle and as a heat sink.But, ultimately as stated above, this repair may be too advanced for a beginner. Safety First!!!!!Weldtek
Reply:Thanks Guys,I decided to get professional help with this part of the job. I guess these are the responses I was looking for. I knew that I didnt like what I saw with the frame repair, and your advice is welcomed. Aside from the framework, I will be welding the rest myself. (trunk, trunk floor and drop offs, outer wheel housings, and quarters). I have had some good luck welding other pieces of this car. I think the key here is I was trying to weld with rusty metal that I cleaned up, but not good enough. Whenever I follow the settings on the welder, and have nice shiny metal that is clamped tightly, I seem to have decent welds. Anyway, you guys are right. I'm waiting to hear back from about three different people I've contacted. Problem is not many people want to come to my garage to work for a day, and I dont blame them, but I will find someone. Here is another weld that I did on the trunk floor. What do you think? These are the supports that hold the gas tank to the trunk floor. Attached Images
Reply:Your spot welds look pretty good to me.  Nice work on this."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25
Reply:Looks good.  Much improved.  MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Originally Posted by James JohnNothing wrong with frugal, but a cracked aluminum frame is junk. Unless there is a warranty, you're going to have to replace the frame on your nickel.Options:1. Garage sale or garbage pick a similar bike and mix parts until you get something workable.2. Get a new frame. As Richard noted, Performance has some decent frames for not a lot of money. I bought one of their Access frames in June for my daily driver, and I'm really happy with it. Be aware that your old parts may not all fit on a new frame because of differing frame tube diameters. Seatpost mounts, forks, front deraileurs are items of special note. Check the dimensions on new (shown on the website) and old (get out your calipers) so you know what you're up against BEFORE dropping coin.P.S. When talking with cyclists, there is no 'L' section. You have a top tube, seat tube, down tube, head tube, seat stays, and chain stays. It sounds like your problem is at the junction of two or more of these.
Reply:DR,check out mr John James other 3 replies. They are all similar BS. I've reported that post as spam, I don't know if mods look at it with just one report, or requires many reports. I hate spammers.JasonXMT 350 MPA Dynasty 280DXSuitcase 8RC / OptimaSpoolmatic 30AThermco Ar / C02 mixerAssorted O/A gear
Reply:Chris, where about are you in the frame, some areas will get much more stress than others, I agree with the above posts that you should develop and refine your technique more before attempting this type of work but I also believe you should work toward being able to do this work down the line, Make sure you find someone who is capable of doing it and if you don't look directly over their shoulder at least take note of how they work through this. Just my opinion, but a 110 machine is starting to approach it limits as far as having enough drive( amperage) to burn this in properly and I know I will get and earfull here but I would not use it to weld heavier plating approaching 3/16 here. In experienced hands your machine should make a proper repair here. Post a bigger picture of the overall frame to show us what you are working on . Good luck and keep at it."Si Vis Pacem Para Bellum"Lincoln Idealarc 250 AC/DCMillermatic 251   Syncrowave 300   30A spoolgunLincoln MP210Hypertherm 45(2) LN 25(2) Lincoln Weldanpower 225 CV(4) SA200   1 short hood    SA250    SAM 400
Reply:Thanks norite and desert rider. Those plug welds did take some practice, I didnt just turn on the welder and get lucky, so my hats off to you guys who know the trade. Ok I will post more pics. I did not wnat to bore you guys, or waste your time. These pics are from the other side. This is a 74 Barracuda and both rear frame rails are rusted in the same place, at the factory spot welds right near the leaf spring shackle support tube. From my veiwpoint this is probably a high stress point in the frame. In the second picture, notice the area to the left of the black bushing. I already had started chipping away the rust, theres only two spot welds holding that thin piece to the heavier shackle piece. Attached Images
Reply:Can't wait to se it all done. I love those old late 60's, early 70's Mopar's. I've got a '71 Fury III that I eventually want to get back on the road, and had several 72-74 Darts as well as an old Valiant and a couple of Dusters. I looked a a sweet Charger last month, but with winter coming I can't justify the money for a new "toy"..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:Unibody, Chyslers answer to the full car frame.  When the sheet metal was new, cars were light and fast, all was good.  You've got your work cut out for you.Brings back memories, (72 Plymouth GTX  RoadRunner).  Sure wish I still had that car, especially watching the Barrett auto auction on tv and what those old cars go for now.  Keep those pics coming, I'd sure like to see them."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25