Morris Minor Owners Club

Yes I practiced on a few bits of metal first but it never feels the same I think the welder is set up ok as it does sounds like bacon, its just getting used to welding where the panels are touching as opposed to where there is a mm gap or so.
Im sure they will improve with practice but for a first go im happy.

I may just put a smear on jb weld over the join then to ensure it is strong enough, I dont really want to cut it out and redo it.

As an inexperienced welder I sometimes blow holes in what I am welding, if this happens how do you fill the hole? I seem to struggle and just make it bigger when I try to fill it. I have read you can clamp a copper plate onto the back to fill holes, has anyone done this with success?

Yes..... successfully over many years / restorations. I have a variety of brass bars which I keep with my welder at all times. Different lengths and shapes, mostly flat bar but one I shaped with a rounded edge on one side for curved panels on the car.

Brass or copper ( non conducting metals ) are great as a heat shink for butt welding. Clamp up the two sheets with brass behind and kiss good by to blown holes. Blowing holes in the metal is usually a combination of too much heat / power dialed in on the machine or moving your torch too slowly. Thicker metal requires more power, the thinner the metal you need to " back off " on the power setting. Experiment
with different thickness scrap metal and see what happens. Play with it and you will soon get to know what setting you should use for any given metal.
I've heard of old style 2p pieces being used because of their copper content ( current coins don't work apparently plus it's illegal to deface
coins of the realm !! ). Other people use standard copper piping 15 / 22 mm dia bashed /squashed flat in the vice or hammer and anvil.
Building site offcuts , plumber's cast offs , skips etc are a ready cheap source. Or you can spend some money on a larger bar of flat brass.

Retrieving a hole ... with or without a backing piece , requires you to build up the weld around the "inside edge ". " Pulse " the torch ,switching on and off again quickly. If you watch the pool of molten weld "glow " on the edge , let the trigger off. As the glow
" fades " and darkness almost takes over again , move the torch just fractionally , a millimeter or two , so that the center of the wire is angled between the untouched edge and the pool / spot of weld you've just done. Torch / power on again for a moment , see a new pool
red hot , let go the trigger... repeat as necessary. If it's a large hole , hit it with alternate welds left and right , so you don't induce distortion with too much heat in one place at a time.

There is an old welders joke ... you don't have to be a good at welding boy, you just have to be good at grinding off the excess weld.

Have fun with the practice , deliberately use too much power ( and blow a hole ) then turn it right down so you get a little surface globe / blob of weld ( no penetration of metal and the blob will "knock off " with little effort from a hammer ). By exploring the two extremes you will soon get a feel for the "right" setting for your welding machine. Each machine will be slightly different , so if you borrow some else's or buy a new machine , even an experienced welder will " play with the settings " on scrap metal until they are happy with the set up.
Very few of us mortals are naturals , the majority of people have practiced , practiced until they got it right. The satisfaction when you get it right is immense.
Bob

MagicMorris wrote:As an inexperienced welder I sometimes blow holes in what I am welding, if this happens how do you fill the hole? I seem to struggle and just make it bigger when I try to fill it. I have read you can clamp a copper plate onto the back to fill holes, has anyone done this with success?

I’m a reasonably experienced welder and I sometimes blow holds , it comes with a project like this and is to be expected at some point, there’s always one section of old steel that’s to thin to weld, the key to filling a hole is simple let the weld cool before attempting to fill a hole , then make small tacks around the hole ,letting each one cool once you’ve done that you can gradually build up the hole with larger tacks. I find it’s easier welding the Morris then new cars , I think there made of proper steel!

A valiant effort especially as a novice butt welding with a MIG.

Putting on my constructive hat. The reason you see a crack after you have ground the weld is that your welds are not penetrating, this can not be fixed with JB weld or anything similar it requires welding.

Looking at your welds you appear to be moving a little fast giving an uneven look to the weld bead, this could well be the cause of the lack of penetration.

When butt welding with a MIG your two panels require a slight gap. This is to allow for the constant flow of wire. Without a gap the joint will expand and cause the repair to warp.

Anyway, a couple of things. First do not be afraid of the power switch on the MIG, you need amps for penetration. With a 130 or 150 amp MIG and 18 gauge steel you should be using a higher setting but not full power. Second do not panic and rush along the join.

Now something I hope you will try that will make your life much easier. Once you have your panel in place with a gap of around 1/2 - 1mm add a tack weld every couple of inches. Now I want you to weld a 1 inch section but not in a continuous bead. Instead start a tack weld, as the steel turns red form a little circle with the torch and release the trigger. You should see the molten pool follow the torch. Stay behind the mask and just as the red glow starts to fade from the first tack start another one just on the outer edge of the first, this time when you form your little circle push the weld pool into the first tack and release. Continue doing this for one inch. You will end up with a row of equally sized over lapping tacks that are relatively flat and have full penetration. Continue doing the same along your join skipping around to spread the heat and be sure to swallow up you original tacks.

After 23 years I can honestly say I am quite experienced at buzzing cars back together. Hope it helps

Rod

Thanks alot for your comments, all taken on board and I will defo give it a try. Most of that piece penetrated so should hold fine as its only the boot floor.
I have just replaced some of the boot floor where the dome is but stupidly cut off the execess level with the chassis rail before realising that it needs to come out further and have a 90 degree bend to give the inner wing its bottom fixing point
Now the dilema of do I take it back off and redo or just add the extra steel on I need. All a big learning curve

Thanks Again

Dome issue

If I may suggest, looking at the first picture above, looks like you are moving along the weld too quickly, hence the height of the weld form, there will be little penetration in that case. I found good results by 'pushing' into the metal while moving along. Good luck.
Ps don't use jb weld, re weld!

Try to keep in ming that at some point you and your family and possibly someone else and their family will be relying on your workmanship to keep them safe. The entire floor of a Morris Minor forms the structure that supports the chassis, there is therefore no part of the structure where you can say 'it's only that bit , it's doesn't need to be that good'. I am in no way trying to put you off but you need to slow down, practise and improved your new found skill.

Rod

If I can add a comment: practice, practice, practice. Get some scrap and keep having a go at it.

Not that I'm a great welder. I'm a still terrible welder.

But I'm much better than I was and I can see the light at the end of the tunnel.

BrianHawley wrote:

But I'm much better than I was and I can see the light at the end of the tunnel.

So could I, till I went back over the pinholes

Mark Wilson wrote:

BrianHawley wrote:

But I'm much better than I was and I can see the light at the end of the tunnel.

So could I, till I went back over the pinholes

that is the issue, when you have sanding too thin and try to add more weld in you blow through again and it ends up looking worse. I guess the answer is turn the power down and use copper on the back

Cause and effect, Magic. You will have noticed that it is very difficult to only grind the weld and not the surrounding surface. When the weld penetrates properly it will lay down much flatter because the filler rod is being absorbed into the join. This will then require very little grinding and have far less effect on the surrounding metal. Currently most of your weld is building up quite high on the surface causing you to spend far more time with the grinder and effecting the surrounding steel much more. Turning the power down on the machine will simply exacerbate the problem.

Rod