Power & Wire Steeings???!

[outraged]

Hey all....i have a craftsman 105 [30-150 amp range].
(i do realize that this is a Century Welder with the Craftsman name on it) - 8 power settings; 8 wire speed settings; both infinite.

i have a few question that i hope you can answer:

1. this thing is rated at 20% @ 105 amps. are the power settings linear? meaning is 105 amps at the 6 power setting? at setting 8 i assume this is 150 amps, and at the 1 setting, 30 amps. is this correct?

2. having said that, and it is true, i cant seem to get this thing to weld on a power setting lower than about 5.5-6 [about 100-105 amps, i think]. what happens is the arc just doesnt start but just melts off the wire. sometimes even just popping and leaving my unwelded wire sticking to the metal. i've tried various amp settings and wire speeds but just cant get it to arc below a 5 setting. and ideas here would be great.

3. also, check out my attached picture and let me know what you think about these welds. this is from a bumper i made for my jeep. the top picture is the tow tabs for my d-rings [3/4" tabs welded through a 3x6x1/4" tube]. the bottom pic is the back side where it comes through. i've only been welding for about 3 months here and there.

i have alot of other questions but i guess well start off with these. just reading other posts, i have learned a thing or two!

check out my bumper pictures.
Bumper Shots

thanks guys
-Carl

[Hobart Expert Rock]

OUTRAGED..........QUESTION ONE IS CORRECT AS I RECALL..... BEEN ABOUT 1 YEAR SINCE I'VE LOOKED T ONE OF THESE...... QUESTION 2 IS (WELL) AS YOU GO DOWN IN YOUR ADJUSTMENT YOU MUST ALSO GO DOWN IN WIRE SIZE.... IN OTHER WARDS EACH TAP IS A DIFFERENT VOLTAGE OUTPUT FOR CONSTANT VOLTAGE......IF YOU DON'T HAVE ENOUGH VOLTAGE THERE IT WILL NOT BURN OFF (SAY .045) THE WIRE WORTH A DARN.......CAN'T TELL MUCH ABOUT THE PENETRATION BUT THE WEAVE LOOKS OK. WAS THIS SINGLE PASS, MULTIPLE PASS......?
JUSDGEING FROM THE SHOT CLEAN UP LOOKS GOOD PRIOR TO WELDING.........SO WERE NOT USEING FLUX CORED WERE USEING A GAS WIRE..............WHAT SIZE??????? WHAT THICKNESS OF METAL ARE THE D TABS......?............AND HOW THICK ARE THEY WELDED TO......... WHAT IS THE MECHANICAL STRENGTH.......? SORRY JUST TRYING TO THINK SAFETY HERE.............. IF YOU NEED MORE QUESTIONS ANSWERED GIVE US (SEVERAL HUNDERED) QUESTION AND WE WILL SEE HOW THE DISCUSSION GOES..... YOUR CALL................SO HERE WE GO................ROCK
[email protected]

[Roger]

Re: Power & Wire Steeings???!

What I don't like about Century welders is they saved a few pennies by not including pressure roller quick release. Even Harbor Frieght welders include that. I would modify that welder if mine to have that feature & probably use a different spring.

1. First MIG welders have Volt settings (not amp settings) and wire speed settings.
Basic missunderstand about MIG welder controls.
Yes the Voltage control changes output voltage but wire speed also controls amps output.

Here is best advice I have seen on MIG settings from Mike Graham.
For deeper penetration, increase wire speed, drag gun instead of pushing, decrease stickout.
For shallower penetration (for thin tube) decrease wire speed, push instead of dragging, increase stickout.
For a larger bead increase wirespeed and slow down.
For a smaller bead decrease the wirespeed and speed up.
For a higher, narrower bead decrease the voltage, drag the gun and increase the stickout.
For a flatter, wider bead increase the voltage, push the gun, and decrease the stickout.

Obviously some of these work against each other. If you want flat
beads on thin tube, then turning up the volts too high adds to the risk of burning through, so you might turn up the volts a bit and turn down the wirespeed a bit so that you've turned up the volts significantly *relative* to the wirespeed, but you haven't necessarily added more heat. You've changed the balance, but not the total amount.

The only way you can find out what volts, wire speed or amps out your machine is really putting out is by measuring it while welding.

Can get good idea of what your welder puts out at diferent settings by looking at Volt/Amp graphs that are often included in welding machines's manual.

If you can weld 22ga. or even 24ga. steel sheet metal using .025 or .023 solid wire that is as good as it gets at low settings of MIG welder and it doesn't matter if there are unusable lower volt settings.

2. Each welding wire has recomended operating parameters. You can go to below url and navigate through products, catalog, comsumables, solid wire, mild steel, pick a wire, then finally click on welding parameters. Then you will see a nice chart that can't be used with your welder as it doesn't indicate actual volts or wire speed.

http://esabna.com/html/esabna02.html

Use the setting chart on door of your welder to get close. Record what material and thickness was welded and actual settings used for future referance.
Even welders with volt and wirespeed indicators often are off between machines so welder has to set it by ear. Make that how the weld looks/tests.

If you have specific question about if your welder is working right call the manufacturer. They really want you to like their products and tell others how great they are. Also ask them for some volt/amp graphs.

People here will try to help as they can.

[outraged]

Thanks Rock & Roger

Thanks guys, good info.

Rock:
i didnt even think about wire size, but it makes perfect sense.
the weld i showed was a single pass. since the d-tabs were 3/4"
i wanted to get good penetration so i cranked the welder to its highest setting and welded slow using .030 solid wire. the tabs are welded to 1/4" steel (actuall welded through to the other size for added strength). as far as mechanical strength, if the welds are good and right, then i assume that the bumper has the 36,000 psi rating (mild steel).

Roger:
oh hand i do have some .024 solid and flux wire. i'll swap to the smaller and see what happens there with thinner steel.
and not having that quick release roller is a drag, although i dont know what its like to have one...i can only imagine.

More ???'s to come when i get a chance to run some more tests.
thanks
-Carl

[Dan]

Outraged

Your project that you have done has me very worried. You are telling us that you used a small (Im assuming 120 volt) Craftsman mig welder to weld together material ranging in thickness from 1/4" to 3/4". The problem with this is that your small machine cannot output anywhere near the power needed to produce sound welds on these material thicknesses. Before attempting any of these joint designs did you do any test welds to establish your parameters. If so did you do any destructive testing to try and help verify what kind of pentration you are acheiving.

My biggest concern right now is with those 3/4" D tabs. Your Craftsman is a short circuit transfer machine, this mode of metal transfer should not be used for welding up a T joint made up of 1/4" and 3/4" material. The proper mode of metal transfer for such thicknesses would be spray transfer. Another option would have been a gas shielded fluxcore wire. However, both of these require a much larger machine then yours.

Im sorry that I have to be the bad guy, but I m just concerned for your safety and the safety of others.

You need to seriously think about discarding these. Or if possible grind out all the critical welds and have a qualified professional reweld them for you using a machine capable of producing spray transfer.

For future reference, if these are the type of welding projects that you want to do , you should first think about taking a class so that you will have the proper knowledge and skill to perform the welding required. Too you need to invest in a larger machine. This project would have been borderline for my MM 210 because of the 3/4" D tabs. Would have got myself a roll of gas shielded fluxcore wire and multi passed the joint with my machine probably pushing it s maximum output. A good machines for such projects would be a MM 251.

Well by now you have probably called me every 4 letter word you can think of. Please though take my warning seriously , I ve been a professional weldor for 13 years, and to me it looks like your sitting on a time bomb just waiting to explode. Sorry about the cliche.

I don t want this to all be negative. So I would like to add that appearance wise those are some very nice looking bumpers.

[outraged]

Thanks Dan

Dan

thanks for the straight forward and frank reply - no seriously!!

i did have some concerns about the penetration on the 3/4" tabs. it really was a last minute decision to use something so thick. the front bumper was not made by me and used 1/2" high strength steel for the tabs. i wanted this but...well thats another story.

now as far as the craftsman welder specs, the specs do say that it can handle 1/4" (which i assume is at the highest setting - 150).
i did a little test on some 3/4" steel and it appeared that i was getting penetration, so i went ahead with it. i did no type of strength testing on the bumper yet. i guess i probably should before i really need to use it. oh, and i dont think the joint can ba called a t-joint since the 3/4" tab goes through the steel to the other side - or is this still technically a t-joint? i absolutely knew that i would not have anywhere near the strength desired if i only welded to the face of the steel.

so, i will definately look into my options here. and thanks again for your reply.

oh, and you mentioned gas shielded flus core wire. i thought there were basically two types of wire for mig's; 1- solid gas sheilded, and 2- gasless flux core wire. so what is gas sheilded flux core wire? i used gas shielded solid wire .030.

i only called you one four letter word at first, but then i took it back. i've read alot of your posts and you do know you stuff, so i guess i cant really complain.

thanks
-Outraged

[Guest]

Re: Thanks Dan

Originally posted by outraged
Dan

thanks for the straight forward and frank reply - no seriously!!

i did have some concerns about the penetration on the 3/4" tabs. it really was a last minute decision to use something so thick. the front bumper was not made by me and used 1/2" high strength steel for the tabs. i wanted this but...well thats another story.

now as far as the craftsman welder specs, the specs do say that it can handle 1/4" (which i assume is at the highest setting - 150).
i did a little test on some 3/4" steel and it appeared that i was getting penetration, so i went ahead with it. i did no type of strength testing on the bumper yet. i guess i probably should before i really need to use it. oh, and i dont think the joint can ba called a t-joint since the 3/4" tab goes through the steel to the other side - or is this still technically a t-joint? i absolutely knew that i would not have anywhere near the strength desired if i only welded to the face of the steel.

so, i will definately look into my options here. and thanks again for your reply.

oh, and you mentioned gas shielded flus core wire. i thought there were basically two types of wire for mig's; 1- solid gas sheilded, and 2- gasless flux core wire. so what is gas sheilded flux core wire? i used gas shielded solid wire .030.

i only called you one four letter word at first, but then i took it back. i've read alot of your posts and you do know you stuff, so i guess i cant really complain.

thanks
-Outraged

I just looked at your picture of the "D" tab, after reading Dan's concerns, and they are justly spoken. The joint design you have there is good...a "T" joint, backed by a butt weld on the inside. If you chamfered the butt joint into a 'V' groove and filled it up, it will be OK, however if you didn't I would suggest to grind it flush, then rotary file a groove 1/4" deep then re-weld it to get deeper into the bumper. Then it will hold anything you put on it. The fillet should have 3/16" leg length, which is hard to do with .030" wire...I would use .035" E71t-11 wire.

Hope this helps

[outraged]

yes Rocky D i did create a V groove with the joint prior to welding.
one of the few things i learned in the somewhat uninformative manual that came with the welder.

thanks
-Carl

[jbear]

my $.02 on off-raod recovery D hangers.

I can't begin to tell you how many of those (and other such home hobbiest contraptions) I have seen fail under the least stressful of tests....almost always with disasterous results. Imagine a recovery strap (or winch cable) pulled nice and taught by the bronco pulling your jeep out of the predicament you got yourself into...

then...snap, off comes the D ring hanger...ad accelorates into the windshield of the Bronco at 1500 MPH. If that makes contact with someones head...they are DEAD....end of story...end of ride...

That would really suck...especially for the nice fella who stopped to help you out of a jam.

In fact...my bronco will only recover stuck vehicles via a rear. After some serious inspections, I might consider a class three hitch, and that's only if the rear is underwater.

Most competions where recovery is probable...will not allow the use of welded anything...unless there are a couple of bolts through it also.

Food for thought.

over,

bear

[Roger]

Aboard USN ship every padeye is welded by certified welder but that's not good enough. By each welded padeye is label with load rating, test load and date tested, but that's not good enough. Every welded padeye is retested on regular schedule and date of test entered on plate. Then that welded padeye is good until new test is required.

[Jas]

I like the the looks of your bumpers and I am going to build myself a set for my cherokee.


A while back I found this on the web and it scares me a bit to buld my bumpers such that the pull tabs are welded.


The picture is attatched.

[Jas]

The Picture that I mentioned.

[Al T.]

That's a sobering situation. Like Rock says Be Safe Out There.

[Hobart Expert Rock]

ABSOLUTELY SPOOKIE ISN'T IT...........CONSIDER THIS A 3000 POUND CAR MIRED DOWN IN THE MUD SHALL WE SAY NOW WEIGHT 4500 LBS. PLUS THE RESISTANCE OF THE WATER AND MUD ARE WE AT 5500 POUNDS YET, AND NOW THE GRAVITY FACTOR FIGURED IN........... MY OH MY...........THIS THINK WEIGHS SEVERAL TONS BY NOW............ HOPE MY WELD JOB WAS DONE PROPERLY............WONDER WHERE THAT GUY WAS WHEN IT COME FLYING BACK AT THE SPEED OF SOUND AND WENT RIPPING THRU HIS SEAT JUST ABOUT WHERE HIS HEAD WAS...........LET'S BE SAFE OUT THERE...............................ROCK[email protected]

[outraged]

ok......

well, i certainly do appreciate everyones point of view and expert opinions, especially the picture of the tow strap through the windshield...scary!!!

thanks to you guys i am feeling more and more compelled to take the thing off and re-v-groove the back side where the 3/4 tabs comes through [deeper and more power and more weld passes]...i can make a better weld, i know, but it'll be a pain in the arss! the bumper must wiegh near 90 pounds.

i did do alot of research on other companies bumpers and many do weld their tow tabs to their bumpers. some just to the front side [standard t-joint], and some all the way through the bumper. however i have not found any that were bolted on, either with solely bolts, or bolts and weld.

personally, i feel that the weakest point on the whole bumper are the mounting bolts - [provided that my welds are good and proper]. i tried to get grade 8 but it was metric so all i could find was metric class 8.8 [is this the same as grade 8?]

let me try to explain the mounting system. it might be tough to visualize [jas, you might know better because you have a cherokee].

ok, there are 8 bolt mounting points for the stock bumper, i re-used these for my new bumper.
1 - i have a 3/8" plate bolted to the 8 points
2 - i have a 3" tall i-beam welded to the 3/8" plate
2a - since this is the most important strength hold, i
preheated the areas i was to weld, hoping for better
penetration
3 - the bumper is then welded to the other side of the i-beam, once again preheating was performed
4 - for extra pulling strength for the entire bumper i made a brakcet that is welded to the bumper and extends about a foot down the frame rails and bolted there with grade 8 hardware

that is basically it. let me go outside and see if i can get some pictures to help illustrate what i did. but once again i do see where you all are comming from as far as strength, so i will re-group and see whats what!!! thanks.

-Outraged