21 replies to this topic

[castafiore]

I am currently trying out citric acid as a deruster. 4kg for £13 from ebay. I have found the Bilt Hamber Deox C to be pretty good but it is £13 per kilo plus about £3 p and p iirc. Deox Gel is good for small areas but it would cost a fortune and take ages to do the whole shell with gel.

It looks like mostly surface rust so I would try sanding it first. I found a Dremmel with a burring accessory bit is great for getting out pitted rust and into seams and grooves. Then I would get some epoxy primer on it asap.

I have only just registered but I have been reading this forum for months. What a great forum it is. I don't have a Mini but came across the forum whilst googling and have learned so much. The resto threads are truly inspirational.

Edited by castafiore, 15 June 2014 - 10:15 AM.

[sonikk4]

Be careful with pitting removal. Mini external panels are thin 0.9mm so you will end up with either the metal thinned right down or possibly even through.

[castafiore]

Fortunately, I don't have a mini, but obviously you have to be careful. I have found that Deox gel followed by Dremmelling gets rid of most pitted rust without going through the body. If you don't get back to shiny metal then inevitably the rust will reappear. I wouldn't want to use rust converters on visible metal as I think the rust just comes back through eventually, but that does look like surface rust that sanding and priming would sort out.

[1984mini25]

Cheers for the info folk.

One thing that has me thinking though, that Deox-gel, it says to rinse with water... this just seems a little against my common sense!

I think I might get over to halfords/generic other store, see what they have kicking about, couple that with the nylon pad things.

I shall report back laters.

 

 

I used some green snot looking rust 'converter' stuff that was recommended when I fist bought the mini to 'treat' some surface rust on the front floor pans and only chopped out and replaced the holey bits. Admittedly 8 years on, I've just had to replace the floor pans for a second time as the areas that were treated with the converter had finally rusted through. But in doing so also meant having to chop out the still sound previous repairs, so in effect only saving a few years to still end up doing the same job twice.

 

Hence why I've always stuck to flap/strip disks and wire brushes/drill combo for removing surface rust, witch is also a lot faster than waiting 20 mins for a pot of goo to 'work'  and then having to be washed off afterwards.

[Morry Stu]

Not all rust convertors are the same.

I wouldnt use citric acid.

Mar-hyde really good if you can get it.

Its what the pros use on badly rusted bodies

http://www.therustst...FAQs-W48C2.aspx


http://3mcollision.c...erter-3513.html

Mar-hyde uses tannic acid. Its actually better than phosphoric acid.

http://en.m.wikipedi...iki/Tannic_acid

Edited by Morry Stu, 16 June 2014 - 07:23 AM.

[Daz1968]

The mar-Hyde product being water based is probably similar to hmg ferrozinc which is often used on boat hulls when blasting isn't practical. I have used it in the past but as I have never used any of the vehicles daily and never in the winter it has never had a good test. I have put a coat of it on my wire brushed front subframe but it didn't really have any rust on it so was just for precaution.

[Morry Stu]

Mar-hyde ingredients off the MSDS tech sheet

Tannic acid is what does the chemical conversion. It turn steel black.

WATER
VINYL ACRYLIC POLYMER (NJTSRN: 8387P) ISOPROPYL ALCOHOL
METHYL ALCOHOL
TANNIC ACID
BIS(2-ETHYLHEXYL)PHTHALATE SYNTHETIC AMORPHOUS SILICA, FUMED, CRYSTALLINE FREE

It leaves a polymer coating on the surface of the converted rust to form a protective coating.