I use a cordless angle grinder, far less power but then far less chance of doing myself any damage.
If you hunt around they are quite cheap as bare units if you can find one which takes the same battery as something else you have.

I have been back under the car again for a short break from work and think I probably will get a soft wire brush for the grinder and give it all the once over. There are enough 'little bubble' on the original grey paint to suggest more rust lurks beneath.

The reason I was back under the car was to try and remove the three remaining nuts holding the rear ARB on.

The first one I had reasonable access to so having decided that it was not coming off using any nice method I resorted to cutting a groove into it with the Dremel and then beating seven shades out of it until it moved. Pipe pliers helped once it had freed a little. Watch out for shattered cutting discs when doing this, goggles perhaps?
https://farm5.staticflickr.com/4629/...dbddd8bd_c.jpg20180122_165300 by WCA!, on Flickr

The next two nuts promise to be more challenging because of where they are located. They both do the same thing which is to hold a rubber bush in place between the car and a plate that hooks in at one end and bolted at the other. We are working at the bolted end.
https://farm5.staticflickr.com/4672/...b3cd876a_c.jpg20180122_165613 by WCA!, on Flickr

The challenge is that the ARB blocks access on two sides of the nut, the bracket blocks another side and the final side is blocked by a metal plate that appears to be part of the old exhaust hanger (possibly?).

So basically you have a rusty nut to which you have no real access except with a 13mm socket that just spins.
https://farm5.staticflickr.com/4610/...aa5aac31_c.jpg20180122_165420 by WCA!, on Flickr

The passengers side is slightly better as it doesn't have the exhaust plate but there is a different bit of metal blocking access to close to use a short 13mm spanner. The ratchet ring spanner shows how tight space is as that will not fit over the nut because the ARB blocks it.
https://farm5.staticflickr.com/4742/...25609e6e_c.jpg20180122_165545 by WCA!, on Flickr

I have quit for tonight and am on a client site tomorrow so you all have 24 hours to solve the problem.

My current thinking is to buy this set of rounded bolt removers for £12 but am happy to be told better: https://www.screwfix.com/p/erbauer-b...FYmk7Qod9q0Ekw

On that one I would use a deep six sided socket, the type that grips the flats. Breaker bar an a piece of pipe on the end of the breaker bar.WD40 overnight. As soon as the nut "cracks", 1/2 turn undo followed by 1/4 turn tighten. Helps to get the crud out of the threads, similar to tapping a thread. Make sure you don't snap the stud, otherwise you're buggered.
As a last resort use a nut splitter.

Consider something better than WD40- it's very general purpose. Plus-Gas is pretty good.

From the Garage Journal site

Penetrating oil .......... Average force needed

None ..................... 516 pounds

WD-40 .................... 238 pounds

PB Blaster ............... 214 pounds

Liquid Wrench ............ 127 pounds

Kano Kroil ............... 106 pounds

ATF-Acetone mix.............53 pounds

Very interesting, I'll mix some ATF/acetone and give it a try, I have loads of spray bottles I can put it in.
I have always used WD40, last time I bought WD40 was about 15 years ago from an autojumble, £10 for a 5 litre container and a spray bottle to decant it into. Still must be a third full.

I've nothing against WD40 as a general workshop liquid, it's just that there are better penetrating liquids - even a WD40 branded one.

Has anyone successfully used the heat and candle wax method? Lots of YouTube vids about it.

I used WD40 because I picked up 5 litres for about £10 years ago. To be honest having taken that one nut off yesterday I don't think any amount of any penetrating oil would have helped.

The challenge with the remaining two is the fact they are sat in hollows so I cannot get easy access from any side. I agree there are better penetrating fluids that WD40 and will probably get something else anyway.

I would be tempted to tack weld a nut onto the existing nut as that creates a lot of heat and gives a good new nut to try and undo but will try those special sockets first as there is not much room under the car to wave my welding stick about

cut the whole lot off, then buy a whole new bar, new flange, the lot and weld it all up good as new.

:scared:

2 points Andy

1 Are you paying?
2 Have you seen my welding?!?

:-)

I have seen this same list in a lot of places. I wonder if it is right, i have my doubts.

A bit of heat from a blow torch can help a lot too. Combined with WD40 ( or similar )before and after, it will sort out most rusted bolts.

I Agee with most of what has been said about releasing rusty nuts.

The challenge here, as I tried to show I the photos is actual access to the nut. It is basically a socke or grips. A standard sockets just spins and grips have no space to work.

I have bought those special sockets so tomorrow will tell. Either success or expletives

If it was me doing this job, by now I would have cut the bolt off with the grinder and replaced it with a short bolt going through the other way. Its easy to hold a nut on a spanner with some tape so it doesn't fall off, feed it in behind the bracket and do it up from the front. ( I've also glued a nut on a spanner with a dab of epoxy )

If you are going to resort to an angle grinder, use a 1mm thick cutting disc and cut the nut as close to the threads as possible without damaging the stud threads. It doesn't matter if there is still a little bit of the nut left next to the stud thread the combination of the heat and a small sliver of nut on the thread should be easy to remove, if you can't get to it with grips knock it round the stud with a drift.

I've found that by the time you get to that stage, with the heat from the angle grinder, the nut is ready to almost fall off anyway. Time to clean up the threads and apply a new nut. With a hint of copper grease of course.

If you do damage the threads you can run a thread restorer nut down the thread. The advantage of using these is that you don't need much room unlike a tap & die set. I find that I use them quite often and are well worth keeping a set.

https://www.ebay.co.uk/itm/Britool-R...UAAOSw0vBUkDy1

They are a good idea. Old-timers used to make their own by cutting a new nut in half.

The Britool ones that I have are a hardened steel the same as tap and cut just as well. It is just that they don't need as much room to use.

Today's lunchtime update is that some shiny stuff arrived.

I will be removing, cleaning and treating the old bracket before fitting it to the new front ARB links.
https://farm5.staticflickr.com/4675/...79976461_c.jpg20180124_123025 by WCA!, on Flickr

Another new thing was the special 'difficult nut' sockets. The sockets have a sort of petal pattern and the bit provided with them suggests they are meant to be used on an impact drill. Unfortunately I don't have one but I do have an adapter socket so I can get my big wrench on to the end.
https://farm5.staticflickr.com/4676/...629887c8_c.jpg20180124_123238 by WCA!, on Flickr

Less than two minutes later and the first nut was removed. The second took even less time. Why didn't I get the right tools earlier.
https://farm5.staticflickr.com/4619/...11de8d7f_c.jpg20180124_124109 by WCA!, on Flickr

These are the offending nuts. I think that most of the damage was done before I got the new sockets rather than being caused by them so it looks like they work well on rounded nuts.
https://farm5.staticflickr.com/4608/...b6e3a46c_c.jpg20180124_124802 by WCA!, on Flickr

I am happy to have got the nuts out. I am less happy that the corner of my carpet was sticking out of the garage door when I left it and has managed to act as a wick for all the water so I now have a wet back. Once I get the garage floor a bit drier and have a little time I will loosen off the clamps and release the rear ARB. If it ever stops raining I will blast over it with the angle grinder and then measure it for new bushes and drop links.

A quick bit of wire brushing has added a couple of brackets to the 'ready for paint prep' shelf.

A before and after of the ARB links
https://farm5.staticflickr.com/4705/...90b510e6_c.jpg20180124_171411 by WCA!, on Flickr

The front ARB bush brackers before and after
https://farm5.staticflickr.com/4623/...c45c7fcc_c.jpg20180124_174246 by WCA!, on Flickr

This photo shows the inside of the bush bracket and the 'after' one is still a bit lumpy.
https://farm5.staticflickr.com/4620/...ce445c6e_c.jpg20180124_174259 by WCA!, on Flickr

The second one polished up better than the first so I gave the first another go and it improved a bit.
https://farm5.staticflickr.com/4604/...cdfa1c41_c.jpg20180124_175057 by WCA!, on Flickr

Enough for tonight