Media blast vs. Chemical dip

I had my Dino doors dipped 25 years ago and had a good experience. However, I have seen a resto where the acid was not neutralized and it was not pretty. Lots of rusting in boxed areas. Fixable, but expensive.
I think for the way the Dino was originally put together, poorly with no rust protection in the seams and folds, theoretically, dipping would be the best way to get back to "zero rust" without unfolding all the seams.
Media blasting cannot access the many folded areas very well, or not at all.
It would be fantastic if you could find a way to go a few steps further like the OEM's; dipping with a very thin and rust inhibitive primer process, baking, e-coat, etc..
What do the dippers recommend?

 

Ivan had his Maserati done in this thread. https://www.ferrarichat.com/forum/maserati/344182-vignale-spyder-2779-a-5.html

Found the thread I was looking for. Good luck.
Expensive lesson, Don't let this happen to you. - Alfa Romeo Bulletin Board & Forums

 

I had a car body dipped with great success for a resto a while back. If the place comes recommended, might be a good option.

Markl

 

I am not sure if the Dino has any aluminum sections hidden inside the chassis (which was common place with other Italian companies of the era for structural support, i.e. suspension points). If so the chemical strip process will damage/dissolve those parts. I agree that the in the best of circumstances in an all steel chassis the inner parts of the frame are beautifully cleaned - but if they aren't accessed for sealing/priming - what is the benefit? I have heard that delayed corrosion/paint issues on the chassis can occur if traces of the caustic agents are left behind.

 

Interesting and valid points.
Pete

 

Keep on with the media blasting and save some money! The chassis is full of badly welded piping with leak holes leaving acid inside various voids and making it increasingly difficult to neutralize the acid subsequent. One of dipping companies in UK even warns about dipping a tube chassis (I considered strongly to dip my Dino...but dropped it after extensive investigation). Blast with care, low angle and leave roof and back end for manual cleaning to avoid stressing the plates. Dipping or not, you will need to unfold all seems anyway if you want to be absolutely sure that all corrosion is fixed. Lids and doors in aluminum cannot be dipped, as mentioned before and these components are often very rusty.
I'm having fun right now unfolding my Dino...take a look at the original weld quality, it's unbelievable.....-

Best regards Peter
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My research showed that chemical dipping is best reserved for uni-body construction cars as they generally have drainage passages engineered into their design often times for dip applied coatings that are part of the original manufacture of the shell. In these instances dipping a car works great and it is possible to effectively neutralize the stripping fluids.

On a car like a Dino it was essentially a tube frame with steel panels welded on to it. No two cars are the same as during the welding process breakthroughs by the welder has all kinds of holes in the chassis that can allow dipping chemicals to pool and hide. The risk is very high that over time while driving this chemical will seep out causing a failure of the paint.

Dipping has its place and a Dino is not it.

 

water blasting is the new trend here in Europe.... very gently
a must for aluminium bodies.....
see #00306
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Agree 100% with Matthias. Media blasting with abrasive media can also damage the top surface of the sheet metal (also by generating heat from the friction between the media and the metal). For aluminium bodies also in my opinion not advisable. Newer aluminium sheet is protected by a very thin chemical finish called Zirconium-Titanium to stop corrosion and improve adhesion properties of the metal.
Latest technologies in paint stripping are water based (high pressure) where you can control how much material you want to remove.
Chemical paint stripping needs to be done with great care. The most important thing is to remove all traces of acid or neutralise the chemicals to avoid future corrosion and possible damage to the new paint job.
Max.

 

Is cost the driving factor?

I recall a past restoration where you mentioned a cost for media blasted that I thought must have been a typo as it is multiples of what it costs here.

 

is the only way I go. will not harm wiring! but clean it will

 

Jon, we put 40 hours of media blasting into a steel body/chassis to clean off everything and the work was done by very experienced folks who didn't create any new problems (thankfully). The aluminium doors and other panels were done by hand, I think it was a little less than $5k including priming so your costs seems about the same, maybe a little higher.
I have no experience with dipping but it seems like alot of cleanup time is required to clean the chassis tubes out.
Andrew

 

Once you get the metal clean, it should be washed with an acid etch and primed with a good quality chromated epoxy like Glasurit 801-703G.

On assemblies with an aluminum skin over a steel frame, Duralac (:: Llewellyn Ryland :: Bringing Colour To Life :: )should be used to prevent future electrolytic corrosion. It can be found at:Metropolitan Aircraft Parts Inc. (631) 752-2290

It doesn't take much extra effort to make sure that corrosion never becomes a problem again.

Aloha,
Mark