I have been getting occasional adverts for some “welding rods” that are used to weld aluminium and I was wondering if anyone had used them. They are marketed by a company called Millionus. They appear to be really easy to use so, as I have couple of pannier lids that I need to get welded up, I was wondering about getting some but if they are rubbish then I will get someone to weld them up for me. Yes, I am so sad that I have made my own panniers - it has been good fun actually.

https://www.millionus.co.uk/products...30961102159923

They seem too good to be true which makes me think that there is a catch somewhere - they aren’t very expensive and I guess they could be used to fill holes on crankcases. If no-one has used them I will get a set and do a review - maybe even do my own video.

I'm sure there's some people on here who have a lot of welding experience and for whom these things are second nature. I'm not one of them, but I've done welding courses in the past and become passably familiar with arc, gas and tig (using someone else's decent equipment) and pretty good (for an amateur) with my own mig. I've even tig welded aluminium bike bits (with the instructor leaning over my shoulder!), but I can't do anything at all with those aluminium 'welding' rods.

I've tried several times to repair stuff with them without success and there's a few projects that could do with their help right now. I have a load of rods and other bits - including the instruction DVD - sitting in my tool chest waiting for the day when I figure out where I'm going wrong (probably via a good youtube video). I suspect my heat source isn't good enough but that costs money whereas the rods are cheap. The feeling I have is that the heat margin between success and disaster is too close for comfort.

Give it a go and video it - I'll watch it, but practice on something of no value first.

Does this mean that you have tried them but to little success? If that is the case And you think that it is the parent metal temperature that is critical then I can see a case for getting a cheapish laser thermometer - I am thinking of getting one for work anyway but this would clinch it.

I have every intention of getting good first before doing something that matters.

Yes, I've tried a number of times to get the rods to 'weld' but not managed it. It's been a while now since I last tried it but from memory there's a number of reasons why that may be the case - I may have useless technique, I may not have cleaned everything sufficiently, I may have been getting / able to get the workpieces hot enough or the alloy I was trying to repair may not be suitable. Again from memory, the last thing I tried it on was some cracked Kawasaki alloy manifold clamps. I couldn't replace them (unobtainable) but I didn't want to ruin them either.

The rods are more like high temp soldering than true welding and it was getting them to melt and run into the alloy that was the issue. Like normal soldering you can't just blob the stuff on, it doesn't take. The alloy needs to be clean and hot - much hotter than normal soldering but I was worried I could overheat the whole thing and just end up with a puddle on the bench. Aluminium doesn't give you any warning - like glowing red etc, so you have to use other methods. I have an I.R. thermometer but I'm not sure it goes high enough (?).

It was on my list of things to revisit but, prior to your post, fairly well down it.

Ally welding is a pretty skilled process, as BoB says, you don't get any warning when it's going to melt, it just goes, so you need to know how much heat you're putting in or you'll either melt holes in it or just blob metal on top which will be useless. Another complicating factor is that aluminium oxidises very readily so if you don't weld it in an inert gas atmosphere (Argon is the usual gas shield) you stand a good chance of ending up with a spattered lump of alumina instead of a weld. Finally there's the Heat Affected Zone (HAZ) that develops where the recrystallised grain structure meets the original grain and that's where it tends to break, adjacent to the weld rather than through it. I'm not a welding expert but I believe if you preheat the weld zone or post heat treat the entire component you can avoid a lot of the HAZ problems - but again it's a question of knowing how hot and how long.

The thermometer I have looked at goes up to 550C and the melting point of aluminium is around 660C but the rods talk about a temperature of less than 480C so there is a decent amount of wiggle room there. I suspect that it is a two person job - one to heat and monitor the temperature and the other poised to apply the rod. The thermometer is a laser infrared job so non-contact and instant - the trick I guess is to get the temperature just right across the workpiece.

Aluminium oxide starts to form quickly at around 450C so the final 30C gain needs to be done quickly. The other thing is making sure that the aluminium doesn’t anneal - in my application for my pannier lids this is not a big deal but other applications may not be so forgiving.

The rods have arrived and they seem pretty easy to use. Surface prep is important as has been rated by others - the kit I bought cam with a toothbrush sized stainless steel wire brush - the brush is very abrasive on aluminium.

Points to note so far:
The size holes you can fill is limited to about 8mm diameter in my very limited experience and as you move towards 8mm the thickness of the covering gets thinner so ends up more like a film towards the bigger holes so if pressure is involved for big holes forget it. I think I would braze a patch of aluminium over the hole if bigger than, say, 5-6mm.

If I was to be putting a patch over a large hole then I would prepare the surface around the hole and the the patch. Apply the rod to form a “puddle” around the hole and then do the same thing for the patch contact area. Finally heat the patch and hole area to get the puddles liquid so that the patch can be placed over the hole sealing it.

Ensuring the piece stays still during the cooling process is important as the filling metal stays liquid longer than I expected. My fault entirely.

For a butt joint it is better to have access to both sides of the joint to put a “weld” bead down both sides.

You can easily make smooth looking joints easily and they seem to be relatively strong - it is NOT welding so it is weaker but it could be a simple remedy to carry out a bodge repair until such time as a proper repair can be done.

The rods are lightweight and don’t take up much space so I can see myself taking some on a trip - the heat source can be from a plumbers torch so should be simple to obtain locally.

I still plan on doing a video but that will have to wait for a quiet day at work and some time to prepare samples.

So which one did you buy then? Maybe you could give us some tips about welding.

OK. Tips about welding with these rods.

1. Preparation is key
2. They have their place but not for something structural
3. I am rubbish at welding, these make me look good and allow an even line to be made. Sometimes, in my case - definitely not every time - so the tip is don’t ask me to do it for you
4. The rods could be used to cover over a small - up to 7mm say - hole but not to any great pressure.
5. I will use them to seal up the corners of my pannier lid - non-structural and could be made to look pretty good.
6. Powder coating goes over the top as if it were normal metal (which it is of course being an aluminium alloy)

I still have to edit the video I made but have yet to have any time to do it.

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You will have to do without pocket handkerchiefs, and a great many other things, before we reach our journey's end, Bilbo Baggins. You were born to the rolling hills and little rivers of the Shire, but home is now behind you. The world is ahead.

I'll look forward to the video as it sounds as though it went reasonably well for you -if a little hit or miss. What did you use as the heat source?

I used a gas burner we use at work for cleaning off hooks which have acquired too much powder coating - I have a powder coating factory. It would be fair to say it isn’t too subtle and that may be the reason I have been - as you say - a little hit and miss. I used that as it was to hand.

I do have a nice neat torch that is far more appropriate for most applications - it is similar to this one https://www.screwfix.com/p/rothenber...ignition/82945 - when I do my pannier lids I will use that torch.

One thing that I should point out is that using too much heat affected the strength of the samples I used as the process annealed them softening the aluminium. Hopefully with a more delicate torch, and touch, the lids won’t anneal - this will mean having to get it right first time on each corner.

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You will have to do without pocket handkerchiefs, and a great many other things, before we reach our journey's end, Bilbo Baggins. You were born to the rolling hills and little rivers of the Shire, but home is now behind you. The world is ahead.

Having joined in Ted's 'Aye' thread and read about FB v. HUBB, I thought maybe HUBB needs a bit more traffic with bumped threads.

So I'll share an ancient anecdote about aluminium welding. (Or soldering I suppose.) Pass by if old stories aren't your thing...

At the 1970 TT (as a spectator) I had an 'incident' just before practice week started, the alternator cover of my bike slid along the road a bit, wearing a hole right through it.


I was staying with friends and a couple of competitors who said, "No probs, take the cover off and I'll give you a lift to the Reynolds garage. Ken Sprayson will weld that up in a jiffy."

There was a bit of a queue, with competitors and mechanics with all sorts of stuff for repair. It was an education to see Ken repairing everything that was presented to him. Pretty much all steel stuff.

Then I offered my aluminium cover, with quarter-inch hole in it, the surrounds of which were very feather-edged, out to over 2-inch diameter.

"You lads don't half bring me some stuff, don't you!" he exclaimed.

I suppose he must have changed from acetylene to something else, and first 'tested' the feather edge to see how readily it melted, noting how the hole grew, spending a short while in deep thought. Selecting a rod (aluminium I assume) he set to, gingerly depositing blobs of ali weld/solder on to the feather edging. Sort-of playing with it to just melt bits of rod and a smidgen of feather-edge, growing the thickness until the hole was completely filled. Don't remember if he used a flux and definitely don't remember how he stopped it oxidising.

It looked a magnificent repair and he seemed very satisfied with it.
"Where did it happen?" he asked.
"Approach to Braddan Bridge," I had to confess.
"Don't do it again!"

As I turned to leave I was amazed at the size of the huddled queue that had been studying his artistic work.

A while ago he published his second book of TT photographs - he's quite a serious photographer.

The front cover carries a photo of - the approach to Braddan Bridge, with Mick Grant sweeping through. I'm sure there's no connection, but it's strange what coincidences occur in life.

His repair was long-lasting, it was quite a while before I fitted a new cover. And very sadly, I probably scrapped the old one that he repaired.
"What a stupid thing to do!" I thought when I first saw the front cover of his new book...

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TTR250 - London to Cape Town

Some good info on this thread.
This vid might be of interest.
https://www.youtube.com/watch?v=fKIKsDfRAcs&t=623s

I ordered some more "welding" sticks from eBay - to be honest, they were rubbish compared to the ones I got last time. The temperature that they needed to melt was above the melting point of the material (aluminium) I was trying to join. I will be getting some more from the original supplier as they do what is expected. I was less than impressed by the two different sorts I bought off eBay- I know, get them from a known source.

The first difference between the sticks that I noticed is that both new (rubbish) ones (different sizes and suppliers) were significantly shinier than the originals which were a completely flat matt finish compared to glossy for the new ones.

It may be that the new ones will be fine with higher melting point materials (probably not carbon steel though stainless has been mentioned as a possible material it can join - yet to be tried by me).

When I get more of the original sticks in I will try to get some decent footage for a video and then find some time to edit the video such that it is too the point - the first attempt had a combination of poor camera work and far too long. The thing is that there is great potential for the sticks to be useful to me where I work and be small enough for me to slip a few into a pannier / tool tube to do repairs on the road (getting a heat source from someone else) - I just need to be sure that the sticks do what they say they will do - the second lots just didn't.

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You will have to do without pocket handkerchiefs, and a great many other things, before we reach our journey's end, Bilbo Baggins. You were born to the rolling hills and little rivers of the Shire, but home is now behind you. The world is ahead.

Aluminum is a rather complex metal that is difficult to heat treat. The most reliable welding method is argon welding. During welding, argon prevents aluminum from oxidizing by displacing oxygen. Before you do any work on aluminum, think about the quality of your welding machine. It will directly affect the quality of the welds. I bought my welder from this site https://ratemywelder.com/best-miller-welder-reviews/. For many years it has not let me down. If you want your work to last, then I advise you to choose a good welder intelligently. Fifty percent of the result depends on it.