Re: Larry's 1951 Club Sedan Project

Posted by Larry51 On 2010/1/21 3:06:10

There's a huge amount of work involved in restoring a car, but the cleaning of parts is one of the most time consuming of them - a monumental task (- I'm not telling you anything you don't know!). I have spent about six hours today cleaning and painting parts for my '51 (- brake backing plates, brake shoes, handbrake cable, etc). Reckon anything that assists with parts cleaning is worthwhile information to have.

I'd like to share with you an experience that I had . . . .

I've learned a bit from the blogs here, about using MarineClean and MetalReady. Haven't used MarineClean yet, but I'm an avid fan of POR-15 and have been using it extensively. Generally use kerosene for the foulest greasy parts, then wash the parts down with water-soluble degreaser, then use PrepWash or Prepsol etc. For quite a few items I'll use dishwashing detergent as the final cleaning wash. Then it's Deoxidine (- Phosphoric Acid) for the flat panels that will be primed / sprayed.

Footnote: There is some good information at the following site on POR-15, MetalReady, etc.http://www.ppc.au.com/need.htm

Interesting that it mentions MetalReady can cause a light orange effect . . .

I'm sure their 'light orange' colour was not as dramatic as in my recent experience using Deoxidine.

My story relates to a (- or possibly THE most) commonly used metal preparation product in Australia. It is a version of Phosphoric Acid called Deoxidine TM and is widely used by panel beaters for degreasing and metal preparation prior to spray painting.

I had just gotten my chassis back from being blasted, and it looked beautiful, clean as a whistle. Just like that day 59 years ago when it was made in the factory.



I grabbed the Deoxidine, and mixed it 1:3 with water as recommended. Then I brushed it onto the chassis, to degrease and prep the metal. It is recommended on grit-blasted metal, so I was doing what I thought was the right thing). I had used Phosphoric before, sparingly, on flat panels before spraying a car, so it was nothing new. You put it on, you wash or wipe it off!

But I had never used it on a grit-blasted surface like the chassis.

As I brushed on the acid, it frothed, but within a minute or two it started to turn a rusty brown colour. Panic! I grabbed the bucket of water and sloshed water onto the chassis to rinse off the Deoxidine. Too late . . . the metal that I had 'treated' had already turned VERY rust-coloured, in just a few minutes. There was around a third of the chassis, now looking like it had stood naked in the weather for months . . . .

So, here my lovely chassis had gone rust-coloured within a few minutes. I started drying it off with compressed air, then I got the ScotchBrite pad and started rubbing the orange rust off. It was a lovely shade, reminded me of the auburn hair of a girl I used to date.

There was still a little rust after my couple of hours' hard yakka with the ScotchBrite pad . . . .






A few hours of energetic rubbing and I had most of the rust off. Then I rang the local spray painter and asked him what I'd done wrong. A bit mystified, he said he had never brushed Deoxidine onto grit-blasted metal in his time. He had wiped it onto sheet metal panels then wiped it off with a clean rag, as soon as possible, and never had a problem. Funny though, there had been another chap who had called him this very same morning, with the same problem I had!! This bloke had created 'instant rust', just like I had done. (I think my painter-friend had given him the fob-off, then I called, to confirm that this sort of thing really does happen. He had become a believer).

He reckoned that you wipe the acid onto a small area, then wipe it off a short time later. He was undoubtedly correct.

Amongst other wordage, I told him I was very disappointed.

Now the chassis has been primed and painted, and I will from this day on use treatments with caution, firstly testing them on a small area. Lesson learned.