Lots of help needed please

[Mark4077]

Hi All
I have just purchased a clarke 135te to tackle some repair jobs on an old land rover. I am using Hobbyweld 5 argon/co2/02 as the shielding gas.

I am totally new to welding and have been practicing on the work bench with scrap metal and had some good results running beads and joining bits together.

I have actually managed to weld on a couple of outriggers quite successfully but am really struggling with thinner metals in the footwells.

They are approx 1.5mm thick and I have set the welders power and wire speed as per the clarke manual for that thickness of steel. The existing metal has been cleaned up with a flap disc and is as clean as I can get it.

Gas flow is approx 10-12 litres per min. Is this right for this kind of work? It seemed good for the thicker chassis/outrigger work.

When working with the thinner metals I am constantly getting the weld "balling up" on the joint and it looks like I am placing metal balls on the surface. Also a lot of black deposits (carbon?) around the weld. I have tried varying the wire speed and gas flow but just can't get a good clean weld. I have tried changing torch angle and also torch distance from the surface. Brand new welding tips in the torch.
Any advice welcomed, many thanks

 

[mike 109444]

Think you need to ignore the manual.
If you get a piece of the metal you have cut out / back to good metal then it should have some good metal still left near the edge. Clean this up and practice away from the car till you get it melting the weld wire correctly. Note you will not be able to do long runs on 1.5 with out blowing through so use the "Thin Metal Technique" which consist of lots of tacs spread over the patch (to reduce heat input and distortion) Your welder should be set to almost blow through but because you are not running a bead the blow through should not happen (to often!) Also you can use a copper strip (flattened copper pipe) on the backside of the weld to reduce blow through.
It's a learning curve
And welcome

 

[Richard.]

Ignore the manufactures settings as I've heard them to be most unhelpful. Gas flow sounds to be ok to me.
By balling up do you mean not penetrating the steel at all (sounds strange for such thin steel) sounds a silly question but I must ask that your sure it's steel your welding on.
I would suggest maxing out the heat with your wire feed half way and tune it down till its singing nicely. Can you put some pictures up so I can see the welds. Cumbriasteve has this exact machine so he will be able to help set it up if he looks into this thread.

 

[norlander]

have you got a good earth connection, and have you put fresh contact tip in and are you getting gas at the torch end.

take the tension arm off and lift the top roller so the wire does not feed and pull the trigger to see gas is arriving at shroud.
Post a picture of the job.

 

[cumbriasteve]

Because you have done some decent runs prior to the floor area it would make you think you have invented the issue with the change of area.

My first guess was poor earth connection, is the earth touching the new steel and not the old?

For the thickness you mention, the lowest setting would be the norm and the wire speed is anyone's guess with that machine, mine (same machine) would be above 5 but below 8 and take a fair bit of fiddling to find the ideal between those two.

As Norlander states:... bang some pictures up, it makes diagnosis a lot easier.

 

[Jan]

Are you welding inside a closed garage or is there a significant draught in the area? With your gas flow rate you shouldn't be seeing too much sooting, but if the shielding gas is being blown away you most likely will.

 

[Migmac]

I thought LD floor pans were made of aluminium and held in place with screws, could be totally wrong

 

[ibrooks]

Might also be worth filling in your location (be vague in case you want to put up photos of something that might be desireable to any pond life at a later date). There may be someone near that would be willing to come over and spend half an hour playing with the machine to get the settings right (far easier with experience) and show you what it looks/feels like getting each setting correct.

Iain

 

[ibrooks]

I thought LD floor pans were made of aluminium and held in place with screws, could be totally wrong

The floor proper is but the footwells are part of the bulkhead and therefore steel.

Iain

 

[Migmac]

Cheers Iain, you learn something every day

 

[ibrooks]

Especially if you involve yourself with the rusty/oily bits of old Land-Rovers.

 

[Migmac]

Had a couple through work over the years, one I had was in the garage every month for repairs. Drove me mad, it would never break down at home. Always miles from nowhere and in the days before mobiles. Had some long walks home!

 

[Welding Bear]

I'm still learning and have had so much help from this forum you're definitely in the right place.

First thing, as mentioned. . . Those settings for the Clarke 135te (I have this also) are totally wrong haha! My strategy has been to get some scrap steel the thickness of what I want to weld. Then set it on highest setting. If it blows through I know that's too high. . . Drop it down a setting. Until you're not blowing through. Then adjust wire speed til it's sizzling.

I had the exact problem with balls of crap and soot even though I had gas flow on max. I bet you're welding outdoors. If so, get ya self in doors

 

[Mark4077]

Hi again

Many thanks for all your comments. Much appreciated.

One point that was mentioned but I never stopped to give much thought to was the "earth" clamp connection.

When I did the outriggers I was earth clamping onto a cleaned up part of the new outrigger which in turn was clamped to a cleaned up part of the chassis, which I guess was providing a good enough earthing point.

With the thin footwells I was just about getting the clamp to grip on the 90 degree corner sections but I am wondering if this was not good enough.

I have just noticed on ebay magnetic welding clamps for use on flat surfaces. Must be worth a go for under a tenner.

Just a quick question, should the earth clamp go on the new metal or the existing bit ideally?
Thanks Mark

 

[Richard.]

I'm still learning and have had so much help from this forum you're definitely in the right place.

First thing, as mentioned. . . Those settings for the Clarke 135te (I have this also) are totally wrong haha! My strategy has been to get some scrap steel the thickness of what I want to weld. Then set it on highest setting. If it blows through I know that's too high. . . Drop it down a setting. Until you're not blowing through. Then adjust wire speed til it's sizzling.

I had the exact problem with balls of crap and soot even though I had gas flow on max. I bet you're welding outdoors. If so, get ya self in doors

Said like a pro.

 

[Richard.]

Hi again

Many thanks for all your comments. Much appreciated.

One point that was mentioned but I never stopped to give much thought to was the "earth" clamp connection.

When I did the outriggers I was earth clamping onto a cleaned up part of the new outrigger which in turn was clamped to a cleaned up part of the chassis, which I guess was providing a good enough earthing point.

With the thin footwells I was just about getting the clamp to grip on the 90 degree corner sections but I am wondering if this was not good enough.

I have just noticed on ebay magnetic welding clamps for use on flat surfaces. Must be worth a go for under a tenner.

Just a quick question, should the earth clamp go on the new metal or the existing bit ideally?
Thanks Mark

Two good rules to live by when connecting your return.
As close as you can get
As clean as you can get
It does not matter which side of the joint you put it on just ensure there is a nice short path and it's got firm contact on bright metal.
Earthing on rust is just as bad as welding on rust.

 

[norlander]

on the earth issue, if you have a clamp that has a nut and bolt securing a tab on the end of the earth cable, check it every so often to see if its worked loose.
If you have been getting a fair amount of spatter from the material/settings etc that you are welding,check the shroud or nozzle for accumulated spatter inside which may form a bridge across to the contact tip.A proper set of MIG pliers are handy for clearing that out.

 

[Welding Bear]

Ps, Mark. Are you definitely getting 10-12 LPM on the gas flow? I cant get any more than 3 on mine. You changed the regulator? (We have the same machine)