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Up Topic Welding Industry / General Welding Discussion / welding metal purlins
- - By ryan gaspard (**) Date 05-03-2009 00:45
need some help, i have been putting up metal buildings this past week, i have a vantage 300 and i am looking for advise as to what size rod is the best and what the machine setting should be. i know not all machines weld the same so some ball park figure would help. these purlins and post are primed, would it be best to grind off the paint or weld it like it is. thanks for any help got to do something to pay the bills till things pick back up. thanks again and GOD BLESS.
Parent - By texwelder (***) Date 05-03-2009 01:49
If your puttin up steel buildings its likely your charging by the square foot, don't grind nothing, use 1/8 5p or 5p+ setting depends on your travel speed, I run hot and fast to get it done.
Parent - - By cajun welder (**) Date 05-03-2009 02:10
I welded my purlins, 4"-16ga and i used SA 200 6011 1/8, second gear, 40-45 and it worked well. I didn't grind the paint off before welding and I didn't have problem welding them.  Should have painted the welds after because it rusted really bad.
Parent - - By rig welder6 (**) Date 05-03-2009 02:53
1/8" lo hi hot  130ish, 5p+ will prob crack in time if not right away, use lo hi even if u have to take a little more time i would rather do that than wonder if my weld will hold for good.  But that is just me.
Parent - By scrappywelds (***) Date 05-03-2009 03:55
be a craftsman and grind the primer off, weld with a 7018 and primer the weld zone. burning through paint sucks and some paints it is toxic to breath.
Parent - - By darren (***) Date 05-03-2009 05:30
if its really bad paint , keep a 5/32 6010 series for a burn through pass, a quick way of getting rid of paint. then weld with 1/8 7018. that's if the paint is real bad.
most of the time its just turn it up and burn it in there. some times holding a little longer arc helps as well, all depends what the customer/boss wants.

lots of structural if you were to grind or wire wheel you'd be run off but others want it done differently.
as far as bad fumes paint is pretty bad especially metal based paints, styrofoam is really nasty, but wait till there is a little concrete on your inbed and you weld some of that and get a whiff, you stop breathing immediately and it is really hard to re start breathing, for my dollar rock dust and concrete are the worst fumes. the worst of the worst.
just my 2 cents
darren
Parent - - By 803056 (*****) Date 05-03-2009 14:14
Its best for the economy to weld through paint, grease, oil, concrete, etc. Wet rods work best. Paint the rods with a good quality paint first so you won't have to waste time touching up the welds. Porosity is natures was of letting off gas. With the collapse of oil patch work, there's too many welders anyways and this practice culls the weak ones from the herd.

Stick with satisfying the boss. That makes the most sense. If he knew anything about anything he wouldn't be the boss. Let's face it, if there's someone in the gang that can't do anything right, make him the boss. He'll ride herd over the rest of the crew just to keep his job. His motto, "Do something, even if it's wrong, but don't just stand there looking at it!"

Just trying to play along with the Farm Code thought process (if there is any). It seems fitting for this thread.

Best regards - Al :)
Parent - By darren (***) Date 05-03-2009 19:48 Edited 05-03-2009 19:50
although ive never read one, i would assume there is a greek tragedy about what a man is to do, what is the right way, or the bosses way.
all i know as i get older when someone who is footing the bill asks for me to do something "their" way and doesn't ask my opinion i just do what i am told (unless it is a safety issue).
i am running out of steam to try and correct my superiors. the worst part is when given poor advice which results in a poor product it is either ok because it was authorized by management or it becomes the workers fault for not doing it right. some days you wonder.

a structural guy once told me that a journeyman in structural is one who could fill a gap no matter how big, or in what position without using a grinder or having to adjust his machine.

just tack it, the welds will be hidden so no one will be able to see them and inspect, the welds are way over designed so a couple of strong tacks is plenty.
i either listened or got sent home, direct quote from the boss on my first structural job when i was a kid

i am afraid it only took a couple of weeks of this downturn before i noticed employers/bosses were taking advantage of the old "you wanna keep your job then do it my way now and dont argue", and unfortunately men will have to listen to feed their families. the safety and human rights that have been hard fought for are being very quickly eroded in these tough times both by the will of the top down but also by the dire circumstances of the bottom up that agrees tacitly.

as for the farm code
all paints used on structural must be the specially developed two part epoxy type developed by the "kill all welders design corp" or equivalent.
all parts that mate up shall be made sure to have an abundance of paint between the mated parts so as not to be accessible by a wire wheel before welding to ensure the proper ratio of paint to weldment, especially important when weld must be done in an awkward place while welder is inverted and has no other option but to have head in plume.
darren
p.s. some days i wish i was a florist.
Parent - - By JohnJohn (**) Date 05-03-2009 14:11
1/8 5p+ 190/55. 5p+ is also rated to weld sheet metal so it shouldn't crack. I have done this for over 10 years without a problem. 7018 can be tricky because you are usually welding thick to thin. If your are welding to D1.1, then use a 3/32 7018 and haul a** up. I use a 3/16 x 7" clip on an 8" purlin. I weld one inch on the top of the clip then all the way down for a total of 8" of weld. I use 7018 everywhere else on thicker material. You can use 70+ if you don't mind the restrart issues, or 6011. The trick to metal buildings is speed, because there is very little profit in them these days. If you feel funny about using 5p, get a clip and weld it to a scrap purlin then try to beat the clip off. It's basically the same principle as welding decking, the light gauge metal melts and cools fast. Just my $.02. Good Luck.

JohnJohn
Parent - - By okwelder82 (***) Date 05-03-2009 14:17
Im building a shop for myself right now and I would not recomend using only 5p+. It will eventually crack and fail. Im using 5p+ to tack things up and then going over it with Lo-Hi.
Parent - - By dion_pepperg (*) Date 05-03-2009 15:33
i have built buildings for 30 yrs. structural and pre-fab . its simple weld lo-hi on iron and 6010 or 6011 1/8 or3/32 on purlins and girts it aint going anywhere. Its all about getting the job done when you are contracting buildings. Unless you bid T&M (time and material).
Parent - By 803056 (*****) Date 05-03-2009 20:45 Edited 05-03-2009 22:10
The Farm Code was written with prefab metal building in mind.

Best regards - Al

Ya, that's a shot.
Parent - - By mechan (**) Date 05-03-2009 21:38
and why would 5p its self eventually crack and fail.... ?
Parent - - By 803056 (*****) Date 05-03-2009 22:25 Edited 05-03-2009 22:29
Do you know what the material specification is that is used to make the purlins? Do you know what the alloy composition is? Do you know the carbon equivalency of the material? Do you know what the TS or YS is? Have you ever asked?

Not all steels are the same. So, the electrode used to weld the materials is not always the same. Will all the welds crack? Will they crack every time? Has anyone gone back to see if the have cracked?

In general, if the yield strength of either member over 45 ksi, low hydrogen electrodes should be used.

Remember, no one cares what you used or did until something fails or someone gets hurt. Then the lawyers will want to know everything, including the thread count of your tidy whities.

I commend the poster for asking the question, I'm amazed at some of the answers, and still mystified why many buildings are still standing. ;)

Thank the "Good Lord" that carbon and low alloy steels  are among the most forgiving structural materials known to man and thank "God" for safety factors.

The Farm Code lives!!!!!!!!!!!

Best regards - Al
Parent - - By mechan (**) Date 05-03-2009 23:02 Edited 05-03-2009 23:20
5p+ is recommended for steels not able to be cleaned fully and if users are having cracking issues using the rod, it is not the rod's fault. That being said not taking the time to hit the weld area with a wire wheel and welding over the paint is just asking for the weld to be susceptible to embrittlement. "Farm Code", is just another way of saying that a person is lazy, if one is going to do a project for themselves or especially for another person they should at least make the effort to do the job to the best of the abilities given the constraints of the situation. My opinion on the original question that started this thread with out the posted supplying the specs or extents of the welds to be made would be to take a wire wheel to the joints, 3/32" or 1/8" 7018, and use a rattle can to throw a coat of paint over them post weld.
Parent - By okwelder82 (***) Date 05-03-2009 23:43
Lo-Hi is generally more forgiving than 5p+. You will almost always see a 5P+ weld crack out before a Lo-Hi weld.
Parent - - By Lawrence (*****) Date 05-04-2009 00:49
Which electrodes are recommended for people unwilling to fully clean a joint?
Parent - - By mechan (**) Date 05-04-2009 00:49
JB Weld?
Parent - By 803056 (*****) Date 05-04-2009 02:49 Edited 05-04-2009 02:54
I'm happy to see the Northeast isn't the only fertile ground for welding inspectors and forensic engineers.

There's work-a-plenty anywhere the Farm Code is in use and it seems to predominate where you would expect it to, in the farmlands of America.

This thread is making it sooo verry difficult to keep my darkside in check.

Lawrence, please, please make sure your students aren't reading this thread without adult supervision. It could be the ruination of an entire generation of welders. Everything we've worked our whole lives for gone to "hell in a handbasket" in the time it takes to read some of these responses. 

Best regards - Al   :(
Parent - By tazmannusa (**) Date 05-04-2009 12:05
  1/8" 6011  DC+  65 to 75 amp range. should be able to burn through primer but depends on primer
  Tom
Parent - - By welderbrent (*****) Date 05-04-2009 15:48
Ryan,

As you can see, many people do things differently.  Some may have been done for years, that doesn't make them right.  Some may follow the strictest since of 'a' code, that doesn't make them right. 

IN MY VERY UNEDUCATED, BIASED, OPINION there are some basic places to start.

1)  What does YOUR local building authority having jurisdiction say?  They will usually refer you to local ordinances, or a particular code that you need to follow.

2)  What do the contract documents, specs, general notes in the print pack, etc say the architect and/or engineer are requiring?
In my area, anything over 120 sq ft must have a permit and go through some print approval by local building authority to make sure everything meets their criteria.  Then you will be directed to a particular code that everyone wants used in the construction.

3)  If you are at all concerned with the quality of your work, what code do you generally work to for structural?  You should be using D1.1.  And in this case because of the thicknesses involved you would need to include D1.3.  Then, you should be familiar with AISC, IBC 2006, ASTM, and any others that would apply to your job and local codes.

4)  Once you know which code you are working to, rather required by your local building authority or not, you should set up your WPS, Welding Procedure Specification.  That will lay out most of the questions you have asked.  Rod, machine perameters, over paint, etc.  Without establishing a PQR of your own, you will be hard pressed to be able to run a WPS without removing paint, which is also established in the various aforementioned codes because they establish the material condition upon fabrication, welding, bolting, etc.  The paint needs to be removed within 2" of the weld area. 

5)  As has been mentioned often already,  7018 is the rod of choice (according to engineers and code specs) per structural application.  Don't care what others have done or are doing.  You must have some knowledge of moisture content and the problems associated with it to appreciate this.  Compound that with welding over paint and you will definitely add to the weld embrittlement factor that will lead to weld cracking.  Does this mean 6010 or 11 will "ALWAYS" fail if used in this application?  NO!!  But you better have an established procedure and follow it if you want to use a questionable filler metal.

6)  If you worked in my area, Thank God most of these posters don't,  you would never get a permit without WPS's, certifications, contractors licenses, insurance, bonding, prints from an engineer, and usage of a low hydrogen rod.  The special inspectors, of which I am one, the building authority inspectors, and the engineer will not allow you to weld over paint without an approved procedure. 

That is where I would start in order to get the answers you are looking for.  And remember,  there are many opinions on this board.  Some are more dependable than others.  But you can't go wrong going through your own local building authority to see what is required by them for you to do.

Just my two tin pennies worth.

Have a Great Day,  Brent
Parent - By darren (***) Date 05-04-2009 18:51
i agree with what you said 100%.
i've just found by much experience that bringing up these truths to employers equals unemployment.
if i lived in an ideal world i would love to follow good sense and safe practices 100% of the time.
unfortunately i don't though, so i have to do what the boss tells me or i go home without pay, simple as that. no malice, no nefarious attempts to undermine the whole engineering, wps, pqr, inspection system.
just reality.
thats why i gave the advice i did because in my experience out there, your options are get it done or go home.
if i was working in your area as you stated and my boss told me to follow your procedures and gave me the time and tools to do it it would get done just as i was asked to do it.
if it were my own house i would burn it in there with 6010 then wire brush it and put on a pass of 7018.
i like the  "two tin pennies" thing
i am sure most people don't know that most modern pennies are just coated in copper not fully copper. even the lowly penny is just an illusion.
darren
Parent - - By Cumminsguy71 (*****) Date 05-04-2009 18:31
I have not done any metal buildings but on the fence/handrail I repair put up at times I prefer to clean the paint/primer off, I always think about "impurities" for some reason and then really don't want an ugly weld and my name attached to it on a nice fence or gate. I prefer the 7018 when doing most but have been known to hang some gate hinges with 6010, run it downhill and really pound it in there without blowing through trying to run 7018 uphill on paper thin metal posts with jumbo heavy duty hinges. No code on that stuff......not even farm code, just want to do it right so it does not come apart and their calling me for a redo.
Parent - - By 803056 (*****) Date 05-05-2009 03:45
Brent, my good fellow, you came through and presented a good plan for our friend to consider.

I completely enjoyed kicking up the dust with my comments yesterday and almost, I said almost, felt guilty about some of the barbs I tossed out.

Codes and standards aside, good welding practice would dictate the question be asked, "What is the alloy of the material being welded?"

Without that bit of information, every comment on the correct electrode material is at best a SWAG.

The other thing that scares the dickens out of me is the thought that most welders (and erectors) do not understand the importance each structural member plays in a "building in a can", i.e., prefab or pre-engineered structure. Every member has a function in a pre-engineered building. There are no insignificant members. 

A good friend of mine is a professor in the civil engineering department at one of the universities here in New England. A few years ago his services were retained by the Metal Building Manufacturer's Association (I may have the name wrong) to do a research project on the stability of pre-engineered building. What he found scared the devil out of him. In a number of scenarios the failure of a single purlin was sufficient to initiate a progressive collapse of the structure. As you can imagine, we are concerned with snow loads here in the Northeast. Even the manner in which snow is removed from a roof is critical in preventing a total collapse of the structure. Likewise, braces that are often overlooked by the erector and inadvertently left out can greatly degrade the stability of the structure. As I said, there are no insignificant and few, if any, redundant members in a pre-engineered building.

My word of advice echos Brent's; know what you are doing. Understand the code requirements before undertaking work you are unfamiliar with. Know the material you are working with so you can use something other than the SWAG method of selecting welding consumables and resist the urge to design a connection on the fly.

My practice includes investigating failures and it simply amazes me what some erectors and welders will do because they think they know more than the engineers or anyone else involved in the project. I don't despise them or hold them in contempt. After all, their actions provides me with a steady stream of income. My business depends on contractors and welders (remember, I made my living as a welder for more than twenty years) that take the easy way out. The less they know the more money I make.

Best regards - Al
Parent - - By 803056 (*****) Date 05-06-2009 03:36
One of my friends said it best when I was learning to weld, "Every weld bead you make is your signature. Don't sign for work you're not proud to claim as your own."

His advice served me well and I made it a point to do the best I could on every job I worked.

More than once I listened to the boss and let the wind go in one ear and out the other and did the work as I knew it should be done.

"You don't need to preheat that, the metal is already dry!", still the torch was ignited and the steel was preheated.

"You don't have to grind off that rust, the weld will eat it up!", still the grinder made noise and the sparks flew and drove the numb-skull away.

"Al, do you know why Sam got the job of welding those girders? Because he's fast!", and I spent the next six weeks of overtime repairing them after Sam left the job.

"Al, your wasting gas keeping the torch on that flange while you weld. All you are doing is trying to keep warm!", and I got to gouge and reweld all the cracked flanges the fast welders welded.

"Al, your wasting time buttering the end of that flange, just weld the damn thing.", and I spent the next five weekends repairing the column flanges that developed lamellar tears and rewelding the moment connections the fast welders welded.

Never tell the boss he's an idiot or give them a lot of lip. That's job suicide. Keep your mouth shut, do the right thing. Do the repairs when the other welders screw up and take the overtime money to the bank in your little red wheelbarrow. Don't tell everyone they are doing it wrong, you'll look like a "know-it-all". It will not take long for people will figure it out for themselves who the good welders are. The proof is in the work completed without having to make repairs. I may not have been the fastest welder, but at the end of the day I had more completed welds than most in the gang because I didn't have to go back and rework any welds.  When work was slow I usually had a job and when I finished a project I usually had a contractor or two calling me to see if I was interested in working for them. No, I wasn't the fastest welder in the crew, but no one had to repair anything I welded.

I'm not trying to brag, but I am saying that a "bad economy" is no excuse for poor workmanship or poor welding practices. We're supposed to be skilled welders, not "ham and eggers".

I take pride in my work. Every weld I make is a code quality weld. Every weld I make can stand up to the scrutiny of the pickiest inspector. I read the code and I follow the code. It isn't a guide, it is the minimum requirements that I meet everytime I make a weld.

Sorry for getting on my soap box, but the whining and excuses were hurting my ears.

Best regards - Al
Parent - By DaveBoyer (*****) Date 05-06-2009 04:42
It Only has to be good enough to last the rest of forever. :-)
Parent - By johnnyh (***) Date 05-06-2009 13:40
"The proof is in the puddle."
Parent - - By ESC300 (**) Date 05-07-2009 03:11
Just wanted to tell about what i have ran into lately with a oilfield service company i contract for.They say im too slow because i bevel the pipe and brush the slag out.I think i may have lost there work because i try to do good work.
Parent - - By 803056 (*****) Date 05-07-2009 12:18
We all have families to support and it is a shame some companies have so little regard for the lives of their workers and the general public. However, as a professionals we have a responsibility to ourselves and to the public to apply our skills and to do the right thing even when it means we get "run off".

The boss isn't going to be the one that is out of a job when your work is rejected and it isn't the boss's reputation that is on the line when the work is rejected or there is a failure.

There are companies that you are better off not being associated with.

Whether it is designing, inspecting, or welding, there are those individuals that will never be satisfied that you are working hard enough or fast enough. Darwin usually steps in at some point and those individuals (or companies) are put out of their misery.

As a welder and as an inspector, there are companies I do not want my name associated with because their reputations for shoddy work would cast a shadow on me as well. Just as it was when we were kids, out reputations are established by the people we run with. I tried to run with the best as a kid and I still do as an adult.

You can't please everyone every time, but you still have to be able to sleep at night knowing you did your level best and you have to be able to look at yourself in the mirror every morning knowing you did the right thing.

That isn't to say I'm always right nor that I am the best at what I do, but when I discover there is a short coming in my skills as a welder or as an inspector, I try to do something about it.

From the information you provided, you did the right thing. There are companies that expect you to do the right thing without being told. They are the employers you should seek out. Leave this one in the dust and don't look back. They will find the type of welders they are looking for, there are plenty of them around, but in the end, they will be on the short stick. Life has a way of doing that. It will take a while in some instances, but they will have to pay the piper at some point.

Best regards - Al
Parent - By Cumminsguy71 (*****) Date 05-07-2009 21:23 Edited 05-07-2009 21:26
Well put Al.
Parent - - By Cumminsguy71 (*****) Date 05-07-2009 21:27
I can't see why they would not want you to clean out the pipe inside, is that not what "inclusions" come from?? I lost a job cause I wanted an engineer stamp and design on some awnings, I was told they WERE NOT going through an engineer(even though the guy has one on his speed dial) and they were easy to build and just do it like this(non-engineers) so when they called and asked if I wanted the job($8000 Job) I said "no", short and simple with a "to much liability for me" and cut my ties. Could have used that money but if something happened all fingers would point to me.....a welder, not an engineer.
Parent - - By mastermetal (*) Date 05-07-2009 23:05
If the sheetmetal skin is scewed to the building properly that is almost enough to hold the whole damthing up. Come on people use some common sense. There is a time and a place for everything. Steel buildings are wam bam lets do the next one, its not rocket sience. There are a  thousand of these things around the country put up by 10.00 hr guys, never heard or seen one come apart. 5p 1/8, to hell with the primer.
Parent - By mechan (**) Date 05-08-2009 00:05
You could probably get some caulking guns and tubes of JB Weld and it would hold, doesn't mean that it is a good way to do something. Knocking the paint off prior to welding is not like one saying preheat to xxx degree and post heat to xxx degrees using some odd ball rod specific to the base metal. I don't believe that knocking the paint off on the area you are welding really increases the cost per unit to erect these structures astronomically, if it does I would really be psyched for you to provide the math on that one. If you want to half-ass it then have at it, however; I don't think that the guys question was "how can I do this as jacked up as possible and have it be structurally sound?"
Parent - By johnnyh (***) Date 05-08-2009 00:21
LOLOLOLOLOL.....nice answer mastermetal.  Reread his original question. 
Parent - By tazmannusa (**) Date 05-08-2009 00:47
That about sumes it up mastermetal
 
I welded up miles of barns with 16 gage galvanized Z perlins and strucual gutter perlins with but welded seams. 1/8" 6011 and no grinding coating off, actualy you would be nuts if you did. grind the galvanized coating of of 16 gage and how much metal is left ? let alone that it would take 10 times longer
6011/ 6010 weld will crack, what a bunch of bull. Several have been up so long in a corosive inviroment that the tin has been redone but the original perlins are still there with no cracked welds.
Parent - By JohnJohn (**) Date 05-08-2009 02:32
Amen. Key word: common sense. This horse has been beat to death.
Parent - By raftergwelding (*****) Date 05-08-2009 15:53
I've seen them put up and sheeted 1 day and the wind tear it aprt the next shoddy work i suppose but the wids werent tjat strong hell it even ripped the post out of the ground. but like i said shoddy.
Parent - - By ESC300 (**) Date 05-08-2009 01:31
They said they have driver that can weld sch. 40 and 80 pipe with one pass-keep in mind that they push acid,sand fluid mix on these frac manifolds and related parts.They say 55.00 is too much to pay per hour.I think they care about end of month bonus too much.Better get off my soap box for now and try to find some work,too much grass growing around rig.
Parent - - By 803056 (*****) Date 05-08-2009 13:49 Edited 05-08-2009 14:14
Thank the "Good Lord" there are fellers are out there saving the owners big dollars by doing half ass work.

Its been said that I had a vendetta against all contractors because I'm so hard on them, because I expect the work to resemble the drawings and the welds are expected to pass "strict" AWS criteria. That's not the case at all. There are contractors that are well qualified and do excellent work, but they also charge a little more than the "Fly by Nighters" and they deserve to be paid a fair price for their work. Its the lower tier contractors that can't read a drawing, ignore code requirements, and try to "get er done" that I have no mercy for. They are endangering life and property with their attitude, work ethic, and poor workmanship.

I have no vendetta against the "Ham and Egger", as a matter of fact, I depend on them to earn a good living. Unfortunately I am usually contacted after the fact and the structure has already failed by the time I get involved.

The dumber the contractor, the better my income. Some contractors make it all too easy for me and I almost feel a pang of guilt as I hand the owner of the failed structure an invoice. Then again, they got what the paid for. They went with the lowest bid, didn't ask for references, never asked for welder qualifications and procedures, and saved a bundle on inspection by letting the contractor "guarantee" their work.

What is it they say? "I don't have the time to do it right the first time, but I always find the time to fix it a second time."

E6010, E7018, E7024, E7014; any electrode will work some of the time. The question is, what electrode will work every time? That answer isn't as easy as the question until  the nature of the material you are welding is understood. Tell me to use E6010 or E7018 because "it is compatible by code", or that you can burn through the galvanize with E6010 because your tests have shown that it meets the mechanical properties required by the code or design and I will be more than happy to say, "That's the answer I've been waiting for."  "I've been doing it that way for years." tells me the buildings are accidents just waiting to happen.

As for, "There are a  thousand of these things around the country put up by 10.00 hr guys, never heard or seen one come apart. 5p 1/8, to hell with the primer.", hugs and kisses from me to those contractors. The "brand" of work ensposed by a few keeps my schedule full and my bills paid. Some erectors probably think that a structural failure means the building is flat on the ground. Pre-engineered building fail every day and the number one reason is the erector didn't follow the drawings.

Best regards -Al 
Parent - - By tazmannusa (**) Date 05-09-2009 01:21
So how many building have you seen come down because the perlins were welded with 6011 through galvanized? Any?  I would love to see em got pictures?  I will gladly change my procedures I have used the last 25 years If you can show me that it does not work, Not from just your opinion
Parent - By low_hydrogen (**) Date 05-10-2009 06:40
I've worked for steel building contractors erecting steel buildings and doing millwright work six yrs before i moved into the oil patch.  whirlwind, varco pruden etc.  I live in northwest oklahoma and their are plenty of fly by nighters that stand buildings up on four inch drill stem and make their on rafters and 6010 the painted perlins.  And i can get you pic after pic from about every year around may when the bad weather hits and the wind takes these buildings down or the snow load forces the the roof to collapase. not to say that the 6010 on the purlins  caused them to fail. 

But generally speaking the guys that 6010 on painted purlin use 16 ga instead of 15 gage c-iron purlins than use 28 ga m-panel tin instead of 26ga r-panel or standing seam.  they think that useing four inch purlins and stacking them four feet apart and spanning ten foot some how is better and cheaper than spending the money to have one engineered that is typically 8 inch z-iron on a clear span i-beam building with 20' bays and is enginered to with stand our oklahoma wind, hail and snow load.

That being said I understand the need for the local farm to do the best he can with what he has to keep his hay dry and cattle fed.  It seems to me that most of the posters in here are comparing apples to oranges?  For the private farmer its about the bottom dollar he has no other option.  But on the comercial end its a completely different story at least around here it is if you had to weld on a pre-e building the paper work I always recieved told me what material to use  were to weld and always said 70xx. In my experience it as much about knowing what not to weld on a pre-e b.

I've put up plenty of hay barns and 3/32 & 1/8 7018 uphill on unpainted clean surface is the preferred method!  its not hard while the pieces are on the ground to fig out were the weld will need to be and have it prepped before it gets up in the air, time spent doing the best you can now is money saved in the future.  And a good rep will make you more money in the long run than slapping some crap togather just for sake of time.

"Its better to be thought of stupid than to open your mouth and prove it"
thats what grandad always told me!  I'm sure somebody smarter than me will make me eat these words but thats my late night opinion :)
Parent - - By welderbrent (*****) Date 05-08-2009 15:20 Edited 05-08-2009 15:42
Ryan,  I feel inclined to jump into the mix one more time here;

First, As stated before, you can tell there are many opinions expressed here and we are all vocal advocates of our individual experiences, knowledge, background, and skills.  But, being vocal about something because "we have done it that way forever" does not make it right.

Second, your question has gotten many reasonable answers as to rod recommendations and how to run the welds.  The suggestions have been very good on procedure.  But, the main question still remains as to making sure of the 'grade' of steel so as to be sure the process, procedure, and expecially the rod are the correct ones for the job.  Just because "almost all" buildings are put up with material 'X' and it is "always" done this way, doesn't mean that is true in your situation.

Third, I again would point out the need to make sure of "YOUR LOCAL BUILDING CODES" and the local building inspection authority requirements that you are dealing with.

Fourth, no one is saying that any of the other posters here are advocating bad practice or procedure, but do you have tests and certifications to back up your abilities to put that weld in and make it right?  Your question asked what "would be best".  Removing the paint and/or galvanizing would be "BEST".  May not be necessary, but it is best.  And anyone who cannot remove the zinc or paint without taking away 'too much' of the metal thickness should not be running a grinder/sander.  Al has put forth this position very well, heed it.

I have OFTEN looked over welding where the welders, even in the down flat position, have welded over the galvanizing coating and gotten some very good looking welds.  You could pull, push, strain on it and it held.  But smack it MODERATELY with a four pound hammer and it fell apart, being only truly FUSED/WELDED to one side if either.  Argue with me if you wish, but this is truth and fact, not "I've always done it this way so it must be good".

Fifth, don't know where these buildings are coming from, BUT, I have bought a couple buildings in past years.  The manufacturers asked several questions about my area.  The PRINTS that were supplied with the building were designed to my local codes for seismic, wind load, snow load, etc.  Welding, floor/foundation, everything was called out to the required specs for my area. 

I have also sold buildings for a company that used to sell nationwide.  They did the same thing.  Any building bid, built, shipped to my customers had all the required plans with all the needed details for my customers local building authority.

One more thing, some people need to get out more.  I do know that it does not happen often, especially in light of how many millions of these buildings are in use,  BUT, These buildings do come down from time to time.  I have seen more than one on the ground.  Don't know what brought them down in regards to the buildings structural integrity, but for one it was only a common wind load that removed the entire roof and set it upside down behind the building and the only thing holding up the sides were the tractors and equipment inside the shed when it went.  It wasn't up to the task some how.  And this was not in tornado or other high wind country.

The term gets used a lot (not meaning the people here meant it that way) to excuse lack of knowledge and just muscle through like a bull in a china closet,  BUT do use 'common sense'.  Combined with your skills it will take you a long way.

Have a Great Day,  Brent
Parent - - By mastermetal (*) Date 05-09-2009 14:10 Edited 05-09-2009 14:12
I ll say it again, use common sense. I am cert to weld pipe with stick and tig on s/s and carbon and done miles of it. I have built what seems like miles of hand rail, done complete platform systems in all materials, galv, painted and yes even S/S platforms and railing. Retrofitted brewing vessels. Built huge sculptures for artists in all diff materials, S/S counter tops and hoods, pressure vessels and yes many prefab steel building, from complete new units to add ons and remodels. Each one of these different projects require diffferent procedures. When I tig weld stainless pipe that has to test at 1800psi I do things completely diff then when I am adding a section of galv railing to a platform. There is a time for the farmers code and there is a time for following strict API, ASME and AWS codes to name a few. Use good common sense, take pride in your work and ask questions. I ve said it before this forum is great. I have been in the metal fab world for 25yrs and I learn something everytime I read these postings. Keep it all coming.
Parent - - By 803056 (*****) Date 05-09-2009 20:57
I believe most of us are of the same mind. Before welding a structural member know what you are welding and know what code requirements are applicable.

Building codes and welding codes/standards have been developed with one goal in mind; safety. Safety of the erector, safety of the owner, and safety for the general public.

The requirements contained in the building codes are based on "lessons learned" and in some cases  those lessons are founded on lives that were needlessly lost. When there is a major catastrophe the code bodies study the evidence and make changes in the code requirements where deficiencies are identified. The codes change over time to reflect changes in technology and lessons learned.

As for "show me the pictures of failures", one only has to do a quick search of the web to find numerous examples of structural failures. As professionals, our task is to take the steps necessary to reduce or eliminate the chance our structures will fail. There are several easy things we can do to minimize structural failures:

1) make sure a qualified engineer has reviewed the design to make sure all the design loads have been considered. Each geographic area has wind and snow loads that must be considered. The foundation design has to be reviewed to make sure the soil conditions have been accounted for. Concentrated loads such as air handling units must be considered.
2) follow the instructions, i.e., read the prints and install all the bracing members. Different members have different numbers for a reason. Different piece marks indicate the material is different, the length or size is different, there are more or fewer bolts, or the bolts are a different type or diameter, etc.
3) don't modify any structural member without the engineer's approval.
4) don't weld any member until you know what type of material it is made from. Cold form members obtain some of their strength from the forming process, some of that strength is lost when they are welded.
5) install all the bolts called for. Install the proper bolts and the proper length as specified by the drawings. Tighten all the bolts.

Most of the problems I encounter are easily avoided if the erector would simply follow the drawings and remember that no two buildings are exactly the same. What was done on the last job may be inappropriate for the current project.

If there is one thing I've learned over the years it is, "Common sense isn't common".

Good welding practice is good practice regardless of the application. The "Farmer's Code" is never considered good welding practice.

Have we strayed from the original question? Maybe so, but we've seen many interesting points of view as the conversation developed.

Best regards - Al

Parent - By ibeweldingsum (***) Date 05-10-2009 03:02
Yeah but ya'll know how it is when your a young buck tryin to make a livin. You just keep yur head down and do what the boss tells you to, and don't russel any feathers. (YOU DO WHAT I TELL YOU TO SON!!!) mentallity from a hard a** boss. We've all been through it if you've been in this buisness for very long.
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