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DannyC
07-08-2014, 07:57 AM
Hi Folks,

I have been putting off doing the cross-beam on my Terra-Fox that is being made from 16 Gauge Round tube.
Putting it off because...Danny?
Well because I am having trouble with my welding skills.

However, today I girded my loins (with cheap girders) and gave it a go.

I wish to claim the award for "ugliest welds on the planet" (if there is such a thing).

For some reason that I do not understand I keep running out of position.
It doesn't help that I cannot see the joint area clearly once the arc is up.
I have tried to do it in short bursts with minimal movement but still I seem to go awry.

http://s5.postimg.org/uq0yh82g3/P1030168.jpg (http://postimg.org/image/uq0yh82g3/) http://s5.postimg.org/mlsuchg0z/P1030171.jpg (http://postimg.org/image/mlsuchg0z/) http://s5.postimg.org/ds1xvdt2b/P1030173.jpg (http://postimg.org/image/ds1xvdt2b/) http://s5.postimg.org/qkq1vb4o3/P1030174.jpg (http://postimg.org/image/qkq1vb4o3/)

It is a bit dispiriting to be honest.
I mean who wants to lay claim to having made a bike that looks downright UGLY on every joint?

Ho-Hum.

stormbird
07-08-2014, 09:29 AM
Danny

Not sure I like your welds ?

looking here :- http://www.mig-welding.co.uk/power-settings.htm

I would say your welds are sitting on top of the metal and with little or no penetration ?

I can well understand what you are saying about not being able to see the weld pool , that happens occasionally to me TIG , however unless you have some way of rotating the joint whilst welding you will soon become ' out of position ' that is why Brad prefers square tubing to round it is only tricky on the corners !

I use the fact I can no longer weld a joint when out of position as an opportunity to move around to a different bit of it to weld another 1/4" to 1/2" hoping this will cut down on the distortion , however this method requires you to become good at restarting a weld this if done badly will still make your welds look bad !

bambuko
07-08-2014, 09:49 AM
Yes... it looks the same like your previous attempts :(
Perhaps it's time to swallow your pride and seek some assistance in learning?
I don't mean forums and interweb videos - not the easiest way to learn!
You could do with someone next to you who could guide you...

It seems you are trying to run (round tube joints are not that easy) before you even learned to walk (you have problems with both guiding and setting) ???

Take two pieces of flat 16gauge and weld them together - it's easy, flat, straight and you can check the result on both sides.
Start by adjusting both welder settings higher than you ever did before (you will blow holes, melt things), then back off until you stop blowing holes and achieve satisfactory joints.
Examine both sides of finished weld for correct penetration.
Repeat this exercise until totally satisfied and only then move on...

Next stage would be two pieces of flat 16gauge set at 90 deg and practice until you can weld them OK.

Only then would I attempt what you are trying to do.

When you were learning to drive you didn't just jump into a car and drove away a perfect Stirling Moss behind a wheel, did you?

DannyC
07-08-2014, 10:11 AM
I don't like them either Paul.
They do look "cold" to me too.
I have tried a sequence of "short welds" and as you say the starts/stops also look ugly.
It is my own fault (I admit) in that I wanted to try round tube rather than square and it is a little bit less straightforward.
Getting out of position is altogether too easy so I have brought this on myself.
I also think I am moving too much/fast (scared of burning through?).
Not too sure what I can do about it now other than scrap everything and start again or grind down and re-do.
I know there is sometimes a temptation to lay more weld "over the top" of a bad one, but I'm not sure that is a good idea at all.

Here it is (both ends, both sides) after the generous application of a flap disc.
http://s5.postimg.org/hw7i1meeb/P1030175.jpg (http://postimg.org/image/hw7i1meeb/) http://s5.postimg.org/f4o8b0fvn/P1030176.jpg (http://postimg.org/image/f4o8b0fvn/) http://s5.postimg.org/h5ervuc0z/P1030177.jpg (http://postimg.org/image/h5ervuc0z/) http://s5.postimg.org/onxx4h3dv/P1030178.jpg (http://postimg.org/image/onxx4h3dv/)

Not clever and not pretty either. I need to have a think about this before wasting more time & materials.

DannyC
07-08-2014, 10:22 AM
Chris,

Fair points, well made, thank you.
It is sound advice and well received as clearly I am just repeating a poor performance here.
I think I shall do as you suggest (before I proceed any further with my builds) because I won't be happy with something that both looks ugly and is probably unsound.

I won't say "back to the drawing board" it is more "back to the steel stockist".

stormbird
07-08-2014, 12:09 PM
Danny

I would not scrap that stuff just yet.

I would take the edge of a grinding disc and try to grind down to the root of your welds , there may or may not be metal there and then try to lay a new bead in the root.

Also speed is only part of any welding equation , you can weld fast but to do so you need the current turned up so you get penetration at the speed you are happy welding at.

You should be able to look into the small tube and ' see ' if you have any penetration or not ?

Don't despair we all have good days and bad days at this welding lark , I was showed a TIG welded BMX frame yesterday by these :- http://www.invictusbikes.com/ the welds were superb about 1/4 the width of mine and he says he was self taught ! and had been doing it for about 14 years

http://www.invictusbikes.com/wp-content/uploads/2013/02/vox.jpg

Oh well there is hope for us all yet.....

Twinkle
07-08-2014, 01:44 PM
Hi Danny

Werent you given the offer of your brother giving you some hands on , Might just be the time to take him up on it .
It happens to us all, I know you are not a happy bunny with it at the moment BUT it WILL come right .

bring along a test piece for John at the zombie fest .

Emma

DannyC
07-08-2014, 02:32 PM
Hi Emma,

My Bro' will give me some 1 on 1 tuition when he next visits.
But, these visits are few & far-between (he lives in Cheltenham), so I might need to find another answer to "hands-on" tuition.

I can certainly bring a sample along for John to take a look at. I am not going to let it get me down too much, even if it is a bit disheartening.
I have all the time in the world to get this right so rushing is not the answer.
As Chris (Bambuko) suggests I need to practice with MY kit until with a variety of joints and metal thickness's until I know exactly how/what happens under which set of circumstances.
My brother has been fabricating for years and can adapt/adjust on the fly (as can any competent welder I would imagine).
I remind myself that until January 2014 I had never even touched a piece of welding equipment and this is only July 2014.
I am sure I will get there.

sandman
07-08-2014, 04:00 PM
Hello Grasshopper( Dan)
As Bambuko says round tube is not the easiest joint to weld,but from your pics and knowing the amps you have to play with I would say your wire feed is too high, and as Paul states if your not in a comfortable position then that compounds the problem, try doing a dry run of the weld and see where you can start and stop. you could try pulse welding which is perfectly acceptable and you may get to see a bit more( I think there is a Greenspeed video that demonstrates this method).
If you could bring some prepared tube samples with you darn saafff we can dap up to my works for an hour or two and see what we can do ?
regards
John

DannyC
07-08-2014, 04:35 PM
Hi John,

I have a couple of bits of tube that I could prepare as examples of the real thing.
I will bring them with me. Thanks for the offer.

As suggested by Chris (Bambuko) I dissected a bit of bike frame to get some 1.5mm bits to play with.

I tried 2 fillets and a lap joint.

This fillet starts badly at the left with the bead all on the bottom plate, progresses to being OK in the middle and then begins to wander "up the wall". It's solid though and I can't break it.

http://s5.postimage.org/dqwlfpgmb/P1030180.jpg (http://postimage.org/image/dqwlfpgmb/)

This attempt at a lap joint was a disaster, the top plate just melted along its edge and there was no fusion at all.
http://s5.postimage.org/3uvig2aub/P1030182.jpg (http://postimage.org/image/3uvig2aub/)

This second fillet looks weak/cold but has been hammered flat without breaking anywhere.

http://s5.postimage.org/bow41gin7/P1030183.jpg (http://postimage.org/image/bow41gin7/)

It is not my kit, its me (I'm pretty sure).
But, as I had never even touched a piece of welding kit before Jan 2014 I'm not too "down".
I have lots of time to get it right (just not lots of money).

See you on the 18th.

Tradetek
07-08-2014, 08:39 PM
I have never used a MIG/Flux core machine, but I agree that it looks like you are laying down to much filler metal.

It also looks like you are trying to start on one side instead of starting on the joint itself. I know that you have had issues seeing the puddle, but if you cut down on the material, which I believe is "wire speed", then you might be able to see better because you are not covering it up so quickly with excess metal.

Bill

DannyC
07-09-2014, 03:08 AM
Will turn the wick down a bit and see what happens.

Thanks Bill.

sandman
07-09-2014, 02:13 PM
Hi Dan,

Just as a matter of interest, do you push the gun or pull it along the weld ?

DannyC
07-09-2014, 04:48 PM
Hi John,

If the situation allows ...then I push, else, I pull.

Something about pushing increasing the penetration I was told.

Thanks for looking.

Popshot
07-16-2014, 04:47 AM
The wire feed is too high on those welds. If you've got some power to spare turn that up a notch too. When it's set right you should hear a sound like frying bacon. Unfortunately it won't smell like that. As to seeing the weld pool, do you have the correct grade filter in the helmet? Welding filters come in many grades and mig usually requires one of the lowest shades. Numbers 6 to 8 would be a good choice. Also set up a strong light on the area being welded. A 150W mini floodlight would be great or failing that a powerful torch. Once you can see the weld pool try a slight side to side motion across the joint on the torch. This helps to keep the pool even on both sides of the joint. Try to set the work so that you are welding at a 45 degree downward slope. This will get the weld pool flowing in the direction you are wanting to go anyway. The term for this is stoving and expert welders may well castigate me for offering such advice but I found it useful when I was less than proficient.

hape03
07-16-2014, 06:43 AM
Try another welder? When I dug Out my old but at the time quite ok welder the first welds was not only ugly; Things weren't even loosely attached to eachother. Hmmm, I must have completely forgotten how to do this, was the first thougth. And second. And third. Etc.

Before some more competent welder layed hands on it I found an ooold cheapo edition MIG under a pile of junk in the old mans shop wich was undergoing a massive cleanup. The old welder look so messy so I almost threw it away immideately but tested it first after a second thought.

-Success! (Well, compared to attempts with the newer welder anyway....)

Further investigations showed that there was some kind of semi-fault in the power electronics i the newer welder!
(My guess is that the magic white smoke that makes the black plastic items in the control boxout work slipped out of one of them. They immidately stops working then, believe me, I've seen it with me own eyes.... Once that happened it's very hard to get it back again!)

Therefore; Try how yer hands and settings works on a similar equipment and try do get a diagnose on your equipment from a professional.

(And excuse me if that already was hidden in the thread!)

//hp

Tradetek
07-16-2014, 07:39 AM
That actually is good advice give the issues you have had just moving from one side of the same piece of metal to the other with vastly different results during the same session...

Bill

DannyC
07-16-2014, 09:10 AM
Thanks all!

There is indeed a "plan" to resolve my problems.
Sandman has kindly offered to let me have a bash with his welding equipment while I am dahhhhnnn sarffff (Essex/cockney expression for "Down South") at the weekend.
So, I have prepared some tubes with examples of the most complex of the joints I need to undertake and we shall see whether it is me or the kit in my hands.

I think it is me (and the settings I am using) and not the kit itself TBH.

We shall see. I will report back next week.

flat
07-16-2014, 11:28 AM
Hi Danny. Although I'm not there yet, for me, going from fluxcore wire to mig C25 improved my weld appearance immensely on my HH140, plus it is easier to see the weld puddle. Also, welds on thin metal improved some more with .023 wire. Finally, technique has helped, along with lots of practice on scraps minutes before letting sparks fly on a good piece.

The greatest improvement to keep from burning through is to "pattern" weld, either cursive "e," "o," "u'" or zig-zag. That way, the heat is not focused on one spot, allowing a little micro time for cooling before the point comes by again. Blowing holes happens much less frequent with a pattern weld. I use cursive "e's."