need help with pinholes in weld

[j2100]

I am new to this board and have been welding for a few years. Where i work i weld together 5 inch diameter tubing with .133 thick end caps to make rollers. The problem is that when welding the ends on pin holes show up almost all the time and mostly at the last inch of the weld. we use .035 wire lincon l-56 wire a 90% argon and 10%CO2 axcess 450 welders with coolers and have done everything known to us to try to fix this problem as it has been an on going problem. We have tried different typs of wire, letting no wind get into the weld area,set the arc distance closer and father away and nothing has been succesful any ideas would be greatly appreciated.the machine tacks and welds the caps on automatically.

[pthunberg]

You said you are welding end caps. Do these end caps completely close the tube? If so you are probably seeing air escaping from the heated tube through the weld, contaminating it. I get this on hand rails that are closed on both ends. To stop it I drill a hole someplace, weld up the end caps then let the tube cool and quickly clad weld the hole. A few pin holes in this weld don’t matter because it is non-structural. Don’t know if this helps but good luck.

Paul

[j2100]

No the ends are not closed completly, when the machine clamps on the ends then it is closed we also thought that and cut holes in some tubing and did our own test and still got pinholes. both ends are open for the shaft to go thgough. thanks

[boardmanr]

pinholes in endcaps of tubes

if the end caps that go on the end of the tubes have been plasma cut by an auto plasma or oxy/accet. torch or even machined by a cnc the coolant will also cause this,the cut edges need to be cleaned back to bare metal and any mill scale/paint removed if not this will resault in pinholes or (honeycombs as some call it). If this does not help you're problem let me know..i have other ideas as to what could be doing it

[j2100]

The end caps are stamped out at the machine shop and there is oil residue left on the caps from the stamping process i would assume there is no other cutting process involved.I have been told that the oil left on the caps has nothing to do with the problem but beg to differ.

[PLWeld]

Oil on caps

j2100,
I'm with you on the "begging to differ" part. The oil residue left on those caps is [probably] the culprit. See if you can start cleaning them before the machine tacks/welds them in place. Alcohol or even acetone should take care of this. Let us know if that works. PL

[boardmanr]

Oil on Caps

I agree with PL that the cutting oil/coolant is the culprit. if after cleaning the parts before tacking them together and you still have this problem then you are sucking air into the sheild gas mixture and that could be due to a worn out nozzel and need a new one to bad o-ring in the lead at the wirefeeder and not getting enough sheild gas at the weld area even though the regulator says you are you might not be. I would clean the parts before hand with denatured alcohol(let it evapoate or blow parts off to evapoate it cause it is flamable but does clean them very good), if that does not fix it, I would change my nozzle and put a new one on then if still not then check my lead for holes in it and check o-rings for any cracks in them if they have cracks or look bad put new ones on. all i can think of right now.

[beamwalker]

might have bad batch of wire also. stick in oven @ 300 for 2 hours to bake out moisture.

[tacmig]

Clean that sucker!!

The oil is probably without a doubt the culprit! Use acetone and shine that puppy up and plug them holes!
I agree with the others on this. Been there done that!

TacMig

[AC MOTORSPORTS]

This Is A Hard One

All Of These Are Good To Try And The Only One I Think Of Is To Turn The Amps "heat" Down You Could Be Over Powering The .035 Wirer Size

I Work Out In The Field And We Use Nr-232 And Nr-211 On The 232 It Is Very Hard Not To Get Pin Holes At The End Of The Weld From All The Heat That Bilds Up

I Have A Fema Cert For 3 Inch All Position That Test Plate Was One Foot Wide And Took 7 Hr To Weld With All The Temp Test And Not Over Heating The Plate

Most All The Pin Holes We Get Are From Dirt Or Over Heating The Iron

The Other Thing That I Think You Should Try Is To Change The Gas From 10% Co-2 /90% Argon "we Call This Mig Mix"

If You Are Using That Much Argon With Mig Wire It Is Going To Run Hot

Try A Low Argon Leval Like 25% Co-2 /75% Argon And If You Are Realy Looking For Cold Try 100% Co-2 We Have Some Welders In Our Shop That Use This And Others That Use Mig Mix

When I Get Holes In My Weld It Is From Galvy Or Paint That Is A Field Problem We Have To Deal With "no Cleaning Out Here" Put It Up And Weld

Good Luck With All The Ideas You Got From Hear These Guy Have A Lot Of Good Ones

[boardmanr]

Re: to this is a hard one

i disagree with iron he is all wrong in everything he said and sorry iron you are. Field welding is different than fab shop welding, but will agree that paint and galv is hard as heck to weld on for the most expert of welder, but i bet 20 dollars that the coolant and millscale is the prob,yes you can go to high on the heat with 0.35 wire but i doubt that is the prob i'm sorry i have to tell you that you are wrong on it all and so ya know my welders use 98%Ar/2%Oxy to do all our welding on carbon steel

[AC MOTORSPORTS]

Sorry Will Try Not To Help

i disagree with iron he is all wrong in everything he said and sorry iron you are. Field welding is different than fab shop welding, but will agree that paint and galv is hard as heck to weld on for the most expert of welder, but i bet 20 dollars that the coolant and millscale is the prob,yes you can go to high on the heat with 0.35 wire but i doubt that is the prob i'm sorry i have to tell you that you are wrong on it all and so ya know my welders use 98%Ar/2%Oxy to do all our welding on carbon steel

SO YOU SAY YOU DISAGREE WITH ME AND I AM ALL WRONG IN EVERYTHING I SAID AND YOU GO ON TO SAY FEILD WELDING IS DIFFERENT THAN FAB SHOP WELDING AND THEN YOU SAY THAT YOU WILL AGREE THAT PAINT AND GALV IS HARD TO WELD ON FOR MOST EXPERTS OF WELDING BUT THERE IS THE LAST ONE YOU SAY THAT YES YOU CAN GO TO HIGH ON THE HEAT WITH .035 WIRE BUT THE LAST ONE WAS THE BEST YOU SAY I AM SORRY TO TELL ME THAT I WRONG ON IT ALL AND SO YA KNOW MY WELDERS USE 98%AR/2%OXY TO DO ALL THERE CARBON STEEL WELDING I AM NOT TO SURE ABOUT OXY FOR A SHEALDING GAS

I GEASS WITH YOU THEY GOT IT ALL AND THAT IS GOOD FOR ME I WILL GO BACK TO MY RACE CAR SHOP AND THE 6 FOOT ENGLISH WHEEL AND POWER HAMMER THAT I FABED AT HOME

MY HOBBY IS RACING AND THAT IS LIKE WHERE THE BULL SH!T STOPS IF YOU ARE WRONG THERE YOU ARE GONE AND THAT IS WHY I DO A LOT OF FABING OF PIT CARTS AND HANG BODY PANELS AT RCR AND HARVIC MOTORSPORTS WHY DO THEY FLY ME THERE TO DO WORK FOR THEM AND WHY DO THEY SHIP PIT CARTS FROM SAN DIEGO CA. TO MORSVILLE NC. THAT I FAB AT HOME NOT A PLACE I WORK BUT ONE THAT I OWEN AND IT IS A FULL FAB SHOP LIKE WELDERS AND TURET LATHES AND CNC MILLS, SHEAT METAL PRESS BRAKES, SHERS, IRON WORKER PUNCH , 30'X10' 3 INCH THICK SURFACE PLATE TABLE AND TWO 4 TON LIFTS FOR CARS AND SO ON

YOU SAY THAT IS BULL THOUS TOOLS USE 3 PHASE POWER AND YOU THINK THAT IS NOT AT HIS HOUSE IN THE CITY OF SAN DIEGO ALL THEY GOT IS A SINGEL PHASE POWER SUPPLEY AND YOU ARE WRONG I GOT A BIG ROTERY PHASE CONVERTER BUT THAT IS WRONG 3 PHASE IN RESEDINCHAL HOME


I HAVE TO SAY THAT YOU ARE GOING TO DO GOOD HEAR YOU GOT RID OF ME I WILL NOT BE BACK TO HELP LIKE YOU BUT I WILL GO BACK TO WORK
FOR NOW

WHAT ARE YOU GOING TO DO TALK MORE SH!T TO SOME ONE

AND THEN THERE IS WORK PUTING UP IRON ALL DAY AND THEN WELDING ALL THE MOMENT FRAMES WE ARE DOING A RETRO FIT ON TWO BILDINGS AT PETCO PARK IN SAN DIEGO

BUT THE LAST THING I GOT FOR YOU IF I AM ALL WRONG AND DO NOT KNOW WHAT I AM DOING THEN WHY HAVE I WORKED FOR 17 YRS AS A IRONWORKER IN THE FEILD BUT BEFORE THAT I WAS SHOP FORMAN FOR 3 YRS AND BEFORE THAT SHOP WELDER AND FAB FORMAN FOR 2 YRS

SO 22 YRS AT ONE SHOP IN SAN DIEGO AND IF I AM ALL WRONG THIS IS GOOD FOR ME I GOT THEM FOOLED AND IF YOU LIKE TO CALL AND TELL THEM I AM ALL WRONG JUST LOOK IN THE PHONE BOOK UNDER ASBERY STEEL THEY HAVE BEEN IN SAN DIEGO SINCE 1977 AND I STARTED IN 1986

I DO NOT GET THIS WORKED UP BUT YOU TALK OUT OF THE SIDE OF YOUR NECK AND THAT IS WHAT THIS FORAM NEEDS MORE OF YOU TO HELP THEM

SORRY TO MILLER WELDING FOR USING THE THREAD LIKE THIS BUT I AM NOT SORRY FOR WHAT I SHOULD SAY TO BOARDMANR BUT LIKE THE GUYS I GET OUT IN THE FIELD I WILL NOT STUP THAT LOW WE GOT A SUPERVISER FOR THAT STUFF

HAY BOARDMANR HOW LONG HAVE YOU BEEN A STEEL WORKER TELL ME AND I WILL LET YOU TELL ME THAT I AM WRONG SOME MORE

[boardmanr]

RE:to iron

well lets start by saying sorry for my typo ok you can't go to high with .035 wire so you tell me what is to hot to weld .035 i've run as hot as30 - 32 volts or if you want in amps well over 250 amps close to 300 so you tell me what is hot to weld .035 wire seems i'm not the only one who had probs what it is GEASS or did you mean guess and only reason i agreed with you on the galv and paint is cause i have welded it beforeand the diff. between fiels and fab is you got to deal with what you get in the field(and yes i have and still do field jobs) and in the fab shop it's easier to head you're probs you know you will have off and keep you from having those probssuch as the pin holes in jl's welds and as far as how long i been welding i started in 1986 or 1987 so thats hmm what 20 - 21 years so feel free to ask me anything you want to know but you a ironworker and ironwokers think they know everything sorry to burst you're bubble(lol) you can never know everything, things keep changing and getting better and you will always be learning cause they will find new ways to do everything that is what this forum is for to hear other ideas and what does work and doesn't i said you was wrong and you took it to heart and this is what miller made this for...but no worries you didn't hurt my feelings and i'm sorry i hurt you'res and also i'm glad you have got all the stuff you got it's good to have for a race car builder to have but i build things bigger than race cars...i'll put some pics up here soon for you to see and no disrespect if it was not for you iron heads we wouldn't have skyscapers, bridges and etc that we have in the world today oh and before i forget you had doubts about welding with 98%AR/2%Oxy well i guess don't knock it till you try it is all i can say...i used 75%Ar/25%Co2 for years till someone said try this and it works good..less spatter then 75Ar/25Co2 and
you get better penitration well guess what they was right and another example is i've always welded aluimum with 100% Ar but you can use 75%Ar/25%He so i tried it and had the weld ut tested and passed when the 100% Ar had spots that failed and passed and now lincoln says you can use
75%He/25%Ar and He is a lighter gas and burns hotter in the weld pool so means better penitration..so i'm getting some to test this and will let you know my findings if you or anyone would like to know or if anyone has used it
please let me know











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[j2100]

thanks for all the advice guys i will be trying anything at this point and will respond if anything finally works

[phaxtris]

i disagree with iron he is all wrong in everything he said and sorry iron you are. Field welding is different than fab shop welding, but will agree that paint and galv is hard as heck to weld on for the most expert of welder, but i bet 20 dollars that the coolant and millscale is the prob,yes you can go to high on the heat with 0.35 wire but i doubt that is the prob i'm sorry i have to tell you that you are wrong on it all and so ya know my welders use 98%Ar/2%Oxy to do all our welding on carbon steel

dont worry, sounds like this guy is out to lunch to me aswell