Welding Progress on my 105

[Tim Jobson]

Well it has been slow but steady progress in welding new sills and rear panels to both ends.   Some of the delay has been in getting my dodgey second hand welder to work as it should, and also getting my welding skills back up to speed.

I have welded the new outer sill to the right side and today welded the repair panel that covers the rear of the sill.    I did a but weld to the repair panel, spot welding small sections at a time as advised by other owners who have done this type of work.

Even so the panel still developed some degree of warping so I am not sure if I still did it too quickly or butt welding such thin panels will always create some distortion.     I was wondering if I did a lap weld it may create less distortion due to more metal around the heat affected zone.    If butt welding creates enought distortion that filler is still needed to get the right profile, then a lap weld may even mean less filler .....not sure which way to go for the other  panels.....any one have suggestions??

Tim

[mario-jnr]

welding is not an exact science but when you do it have a bucket of water and a rag handy to dab and cool down the weld line and the metal around it this should keep the distortion down to a minimum this is what ive been told by a mate of mine who has 20 years industry experience in welding oh also for gods sake take your time all that said good job on your 105 i will takling the body work myself once i sort out the mechanicals on my junior so you have inspiered me KEEP MOVING FORWARD it will all be worth it in the end,thats what i keep telling myself 

[njh1964]

Hi Tim,

Looks good so far. I'm by no means a welding pro, but I've found that when butt joining sheet metal, it's best to leave a small gap (ie around a millimeter or so) between the two pieces and then slowly and patiently play "join-the-dots" with multiple spot welds. By this I mean making a spot weld every couple of centimeters, wait for these to cool and then go back and fill the gaps a little at a time, moving from one gap to another, with some cooling time along the way. The temptation is to run a continuous line of spot welds... I find that this is when I get warping.

Leaving the millimeter gap between the two pieces helps to ensure good penetration (ie you're kind of bridging the gap with each spot weld), and this means you don't have to crank up the power up too high, which in turn also seems to help keep warping to a minimum.

By the way, if you find the gap is too wide in places (ie more than 2 or 3 millimeters), you can hold a block of aluminium up to the blind side of the weld, assuming you have access. The weld won't stick to the alumimium and it leaves a nice flat finish on the other side... virtually no clean up required. This method is also great for plug welding up old screw holes in sheet metal. Of course the aluminium block gets a bit hot.

Now a question for you, if I may... where did you source your replacement panels, and are you happy with the fit? In other words, did they require much manipulation to get them to fit properly?

Regards,


Nick

[k76]

I find that some warping is inevitable, but as mentioned can be limited with spotwelds. Still got to make sure you don't put too much heat into the same area, i.e never put down two or more spots right next to each other. Do one spot at one end, one at the opposite end, one in the middle etc until you have filled it all in. I'm not sure about the cooling down with water, I never tried it but I thought that was a big no-no?

Anyway, keep the work up and don't be too hard on yourself.


Kris

[mario-jnr]

K76 i ddnt mead throw a bucket of water on a hot weld that is a big no no your right i ment dab a slightly damp rag over the metal just welded to slow cool the joint but taking your time and welding at oposing ends alternating from one side to the other is good advise to reduce warping but you will always get some slight warping you could finish it off with body filler or lead i supose good luck with it

[Tim Jobson]

Thanks guys, yes it is tempting to lay the spot welds down more quickly especially if the welds are coming out neat, however I did try to keep the max distance between successive welds but probably needed to stop for a couple of minutes every 3-4 welds etc to allow more time for the overall panel temperature to cool.

Nick regarding replacement panels, I sourced my outer sills and repair panels from highwood in the UK, they had the best price.   The right inner sill was a good fit so no dramas however I did notice that their repair panel that goes over the rear section of the right sill was not a good a fit as it could of been, there was a slightly different profile in the wheelarch lip section of this guard that could of been a little more like the original.   The front repair panel looks a better match to the original wheel guard lip profile.... thats next weekends job!
Also that alumimium block tip sounds good, may try it next time.

One aspect that I would of liked was the gauge of the panels, they look to be about 0.8-0.9mm.   I know they are not a structural panel however it would of been better at 1-1.1mm, just feels less flimsy as I tend to over engineer, over weld items and I am not worried about the weight increase.

Tim