Dip or blast

[titch]

I'm stripping my old rust bucket of a traveller to the chassis with a view to remove the rust, patch the holes and have a car that will not need rot removal for many years.

Once I have got the car to the chassis I need to get it cleaned up, paint, rust and years of grot removed.

Should I go for dipping or sand blasting, what has been peoples experiences of them.

My wife recons that dipping is too risky as I will end up with a roof hanging from a chain and the rest of the vehicle will disolve.

[customjob]

Dipping is more aggresive, you stand a very high risk of having a lot less left after dipping, don't what ever you do dip the rear roof or side panels of the traveller you'll never see them again. Sand/Grit blasting is again an agressive medium ok you'll have more of the car left when it's stripped but it'll leave the metal with a rough surface you'll have a lot of work to smooth out before painting. Bead blasting is less aggresive again and doesn't leave such a rough surface behind. I've seen a car that has been soda cleaned and have seen a car being soda cleaned very impressed with the results, i'd say the less agressive choice others may differ.

[alainmoran]

I was chatting with JLH a while back about this very question, and he pointed out that because of the way that the morris is constructed - several sheets folded along the same path and then spot-welded together makes the process of dipping incompatible with the minor - what happens is the corrosive dip soaks into the points where the sheets are folded together, so when the passivating solution is sprayed over the surface there are sections where it can't reach.

The result is that while the shell looks lovely to begin with, the corrosive dipping solution is still sandwiched inbetween the folds of metal, steadily rotting the car from the inside out - as such if you dip it then you are likely to acellerate the rot rather than killing it off.

Media blasting is the way forward, apparently walnut shells are less aggressive than grit or bead blasting, they are however more expensive

[Ratbag]

There have been several lively 'discussions' on some car forums about the quality/service of a dipping company.
Suffice it to say that you should 'Google' any names before use!

[titch]

Thanks for the advice, dipping is definately off the cards then.

I have therefore been looking into blasting and I gather the main issue with it is that if you get it done industrially the pressure they use is high, hence being able to clean a car in a couple of hours. If you use a DIY pressure one, the pressure is much lower, the damage done to the metal much less, however it will take about 15 hours to strip a chase.

But you do at least have the blaster to strip the axel, doors, wings etc.

Soda blasting is great, but it wont get thick rust removed. It is great at cleaning things like the engine as it doesn't damage the electrics, ally etc.

[alainmoran]

My personal perspective is that once revealed, you should be removing the rust with an angle grinder - cutting out the rusty sections and letting new metal in.

[irmscher]

Soda blasting is a good option