Mig Welding advice please

Hi All.

Disco 1 TDi 300 M reg 138000 miles.

Rear Wheel Arch has fist sized hole. Guess it needs fixing before MOT in Sept.
I can borrow a Wolf 130 amp GasLESS Mig welder anytime for as long as I need (family member).
Don't feel confident enough to cut out the wheel arch and replace with a new one myself. Wheel arch on other side is probably as bad! Local independent LR garage quoted me £320 ish to do both wheel arches (including parts). Can't afford that, got about £400 of other stuff to fix on vehicle as well! Also I am sure footwells will need patching soon.

Not frightened to learn how to weld, but not got a great deal of time available cos I got to work to get pennies to pay for repairs (and mortgage and food etc. Boo hoo! Life's a real bummer. Tell you something you don't know!) Sorry - back to the plot.

So Any advice / past experiences welcome. Specifically, what is it like welding upside down with MIG? How can I bend metal sheet to fit profile of wheel arch? Where can I get metal sheet need for job?

Help!

ok if you are going to weld upside down then make sure you have a leather jacket or cover to stop the spitting welds form burning you like a bastard, as for bending metal cut the right length and put a couple of tacks to hold it and beat it with a hammer until it fits. if you are replacing the whole wheel arch then buy one its easyer...

You should be able to buy sheet metal from any good motor spaires shop but it is not cheap...

One other thing when you go to weld make sure you take most of the underseal off or make sure you have a lot of puff in your lungs to blow out the fire you will have...


hope this helps

GOOD LUCK

I have the same problem on both my rear wheel arches, but going to be welded soon...
but I tried to find replacement rear wheel arches and couldnt find anywhere.. plenty for the front, but no rear ones!

did you manage to find any?

as a engineer/fabricator i can tell you now gasless welders aint anywhere near as good as gas welders. at home i use a migatronic 185amp welder and use BOC argoshield gas.
its fairly hard to tell someone how to weld through a forum, best way is to get some scrap and just have a go and get a feel for the machine and wire speed settings,power setting etc. id start on some fairly heavy material and work up to thin stuff before attacking your motor or it could look awful.

[JP];753236 said:

I have the same problem on both my rear wheel arches, but going to be welded soon...
but I tried to find replacement rear wheel arches and couldnt find anywhere.. plenty for the front, but no rear ones!

did you manage to find any?

Click to expand...

just weld a patch and put lots of seam sealer over it and then underseal and you will never notice it and it will last, as long as its welded good

dan_vtec said:

as a engineer/fabricator i can tell you now gasless welders aint anywhere near as good as gas welders. at home i use a migatronic 185amp welder and use BOC argoshield gas.
its fairly hard to tell someone how to weld through a forum, best way is to get some scrap and just have a go and get a feel for the machine and wire speed settings,power setting etc. id start on some fairly heavy material and work up to thin stuff before attacking your motor or it could look awful.

Click to expand...

gas welding is ok as long as you are in a garage or the gas will blow away out side and the welding becomes ****

demitrious1973 said:

gas welding is ok as long as you are in a garage or the gas will blow away out side and the welding becomes ****

Click to expand...

Bollix
Most of my welding is done outside and I dont think its **** - OK yu mite need to turn the pressure up a tad - but its no worse than spray painting outside. Not ideal - but not that bad if you use common sense.

demitrious1973 said:

gas welding is ok as long as you are in a garage or the gas will blow away out side and the welding becomes ****

Click to expand...

thats when u get the stick out mate. or turn up the gas and stay close with the torch. ive sat on windy building sites welding digger buckets up with no problems in the past.

Thanks for the replies everybody!
I didn't state that the 'fist sized hole' is just above the tyre area right next to the side panel,as opposed to under the passenger door.
(can't do photos cos I dont have a digital camera)
I havent exactly sourced rear wheel arches yet, but I think I've seen something on the web about somebody selling them when I did a search on googoil. Will tell you If/when I do find some.
I guess I'll put some big patches on the underside, but I'm quite concerned about passing the MOT because (yes I know there are a thousand posts on this site about welding/MOT pass or fail and the rear seatbelt anchor point) the offside passenger seatbelt anchor point is bolted to the front bit of the rear wheel arch (i.e. the bit under the door). If my patches don't exactly match the original wheel arch then couldn't some jobsworth mot tester fail the job on me?

I'll have a go myself, then take to a local garage for a 'pre-mot' check and see what they say.

Thanks everybody.

Lundrover,
Further to the constructive comments by other forum members. Here are some other thoughts to consider.
1. Always check what lies behind the proposed patch panel ie will it burn!!!!! Is there a fuel line or electrical wiring looms.
2. Prepare the joints to ensure that you are welding clean metal, Any contaminants in the weld pool will either weaken the join or blow out while you are welding like a mini volcano!
3. Keep the joint width between 0.5 to 1mm
4. Use 0.6/0.8mm dia wire with your smaller Mig welders. Having said that my thoughts on MIG welders are the bigger the better. Small MIG welders are fine but the bigger welders have more OOMPH!
5. If possible try to avoid using flux cored wire.
6. With patch panels don't try and weld in continuous seams, spot here then move away and place a spot there. Continue staggering your spotting until the join is filled-This takes more time but will help dissipate the heat and minimize your patch panel and parent metal from heat distortion. Remember HEAT is your enemy. A good cup of Tea or Coffee can be enjoyed many times
7. Use heavier gauge metal ie 1.2mm or at a pinch 1.6mm (than your parent metal)to make your patch from. This will help you to start your weld without blowing a hole in the joint. Looks no different on the outside.
8. Use sunscreen on exposed parts of your skin as MIG welders have a tendency to burn your skin with excellent results. Better still try to cover all exposed parts of your body.
9. I know it is hard but try to weld with elbow length gauntlets (Leather gloves). I am sure experienced welders at some time in the past have grabbed a hot bit of metal with their bare hands by mistake. OUCH!
10. If you can borrow an auto darkening helmet, do so. Good for tak welding.
11. Buy yourself a cheap Chinese angle grinder but always use good quality cutting and grinding discs. Use the very thin section cutting discs. As always use PPE (Eye protection and hearing defenders)
12. When grinding off the finished welds try not to use excessive force to speed up the removal of excess weld. All you will do is create heat with the end result being metal distortion. Once you have leveled the ground surface, get hold of a flapper disc to further smooth the surface.
13. Paint/prime the exposed metal as soon as possible to prevent corrosion.
14. The point of a screw driver is a very good tool for probing around the affected area to try and determine the extent of rust damage. Once you have cut the rust out of a particular area, then and only then is when you will know where to start your repairs.
Anyway I hope this will give you something to work with.
Don't rush the job
Good luck
Cheers
John Wilson

hi mate you should have a look at this MIG Welding - The DIY Guide lots of info and pics

hope this helps

Also look on youtube, there's loads of videos showing how to mig weld, they are good when you don't have a mate near to show exactly how its done

have you tried yrm metal solutions for some replacement arches ?

People ! Thanx again for the advice - especially ozm29c - some good stuff there especially about 'what is around the welding area' - wouldn't want to damage fuel pipe or wiring.
I'm gonna have a look at the link to the MIG welding DIY guide now.
I've already looked at YRM metal solutions, but he doesn't seems to do REAR wheel arches, or if he does, the photo doesn't look like what I want, or if it is what I want, I don't want to be welding that musch stuff.

Once again thanks loads everybody. I'll post how I get on with it all.

is this wot yu are looking for?


if not it could be this or this?

Cool. I want to learn how to weld, just for the occasional bit that needs doing to the car, bike, to make brackets up.

JP, if you need a hand (or someone to laugh at you) when you do some give us a shout, I'd love get some exposure to this

Welding courses - about £60 - local tech college.

or contact yo local welding supplies co and ask them - or call these peeps.

When I sorted mine I just took the airbox/res off etc and welded from the top. Oh use something to protect the engine, rubber pipes etc.

For a weld to pass a Mot it Must be a Continues weld all the way around what ever your welding and more to if your welding neat to a body fixing point (ie chassie out rigger) as anything 30cm from a body fixing point will be checked in a MOT for quality and ive seen MOT inspecters scrape away under seal to see how good the weld is. also its a gray area on land overs as what is the structure of the vehical as the car has its own seperate chassie so some Inspecters will let you get away with ****y weld on the body as long as the chassie is ok

Disco Paul,
Thanks for clarifying that point. Yes I wholeheartedly agree that full weld passes are indeed necessary for chassis components however I was under the impression that Lundrover was focussed on patching panels. That is an entirely different ball game on what welding technique to employ.
Cheers
John W.