Stripping my Chassis and Front Beam - How Far do I Go?

[oscarsnapkin]

I have been slowly but surely chipping away at my ‘73 Thing. I have the body and chassis separated, and the front beam removed from the chassis. I am in the process of removing rust/cleaning in order to get it ready to paint (chassis that is). I had planned on using semi-gloss POR-15, but after reading some of the reviews here, it seems that maybe Master Series might be the better choice. Definitely want to use something I can brush on, and a primer that can be brushed or rattle canned. I was wondering first, how far down should I go as far as stripping the frame and beam? Do I want to go to bare metal? I’m assuming that would be overkill. I have been using wire wheels attached to a drill and angle grinder for doing the removal. Some of the spots have already been taken down to bare, as can kind of be seen in the photos. Since there are already some bare metal spots, do I need to use an etching primer on the entire chassis? Which brings up another question, the inside lip along the tunnel (where the floorpans are welded) should that be primered with a weld-thru primer and then coated after being welded and sealed? I am more or less completely new to any type of body work, and this car is my attempt at a learning experience. Here is some photos of where I have gotten so far. My lighting is terrible, so I apologize for the quality.

This is before I wire wheeled:

After cleaning for a few minutes:

The center tube is rock solid, but it does have a lot of pitting. This is underneath where the hockey stick would be attached. I am guessing there was water trapped in there. I know I can never get this perfect, but any advice on making this pitting less noticeable when I paint?

_________________
- 1977 CEI Sunroof Bus 2.0L F.I. Hydraulic Lifters
- 1973 Thing

"It’s so easy to laugh, it’s so easy to hate, it takes strength to be gentle and kind."

[viiking]

You yourself need to answer that question. What are using the car for? How long do you want to keep it for? Is it a daily driver or do you want a "show car" ? Are you flipping the car?

Whatever the answer is, the better the preparation, the longer the car will remain rust free.

In my case I took everything down to bare metal. For two reasons. Firstly you can see the extent of the problems e.g. rust hidden areas covered with bondo or seam sealer, and secondly the quality and longevity of the paint will depend on how clean and uniform the substrate is.

Regarding the pitting. I believe you can use the silver MS paint which has more pigment in it. This helps to "fill" the pits. Any holes however need to be repaired by removing all the rust and welding up to solid steel.

Re the floor pan to tunnel attachment. You need to get rid of any of the existing seam sealer and inspect the area. Looking at the extent of some of the rust on the rest of the car you should check this. You can try and treat the area with some sort of rust converter, then paint, then re-seam seal. There are lots of companies that make kits such as MS, POR15 that can be used on rusty steel.

POR15 gets a bad name usually because people do not follow the directions well enough. It is designed to work with rusty, not clean, steel. MS seems to be more resilient to poor preparation and clean steel.

Even using good old residential red metal primer and a top coat is better than doing nothing if your budget does not extend to the MS.

Here's a picture of my front end which was hand-painted using a product similar to MS here in Australia called KBS.
_________________
1968 1500 RHD Lotus White Beetle since birth. In the hospital for major surgery
1966 Lancia Flavia Pininfarina Coupe - in the waiting room
Discharged: 1983 Vanagon, 1974 1800 Microbus,1968 Low Light,1968 Type 3

[oscarsnapkin]

[Evil_Fiz]

I am not an experienced painter or body man but have done a fair amount of research on this subject. I am sharing what I have learned in the hope that it is of some value to you. Others here may have better information to offer.


1a) If you have the time and budget to take it all down to bare metal, do so. As stated earlier you eliminate the unknown by doing so. Sandblasting is best but DA or hand sanding with 80 grit will work as well. The wire wheel leaves the surface too smooth for propper paint adhesion.

1b) if you do not take it ALL down to bare metal, either spot sandblast the bare metal or hand/DA sand it with 80 grit sandpaper to give the metal a tooth for the paint to bind to. Sand the painted areas with 150 - 220 grit sandpaper or scuff with a maroon Scotch-Brite pad (Medium - Part #: 07447) or a tan Scotch-Brite pad (Coarse - Part #: 07440) to provide tooth.

2a) If the project will remain unpainted for an extended period of time
- Blow off any sand or grit with compressed air or a leaf blower.
- Wipe the entire surface clean with acetone several times to remove residue and contaminants.
- Treat the metal with a phosphoric acid product. Apply the acid and keep the area wet for 10 Minutes. Thoroughly rinse the still wet acid with plenty of water to neutralize it.
- Move to step 2b when ready to paint

2b) If you plan to paint/coat the project soon after stripping (skip the acid)
- Wipe the entire surface clean with acetone several times to remove residue and contaminants.
- Wipe the entire surface with solvent-based wax and grease remover. Follow the direction on the product's Technical Data Sheet (TDS) to the letter.
- Wipe the entire surface with water-based wax and grease remover. Follow the direction on the product's TDS to the letter.
- wipe the surface with a clean tack rag.
- Apply two coats of Master Series silver. Follow the TDS instructions to the letter.
- Apply 1 or 2 coats of the MS Chassis black or AG-111 in clear or color as a topcoat.


- The cleaner the environment and the surface are the better the end result will be. Avoid rushing or cutting corners If you have the time and budget to do so.
- southernpolyurethane.com makes good, affordable products. Get the wax and grease removers from them. Look at their other products a well.
- Invest in a half or full-face respirator. You will need it for blasting and painting.
- invest in a pressure pot sandblaster. It will make blasting the chassis and hard-to-reach areas of the body a lot easier.
- Use crushed glass or coal slag as blasting media.
- For "Driveway/Back yard" blasting, build an enclosure out of PVC pipe and plastic sheeting (about $200) to contain and recover the blasting media. Collect, sift and reuse the media if money is tight or you just don't like waste. The enclosure can also be used as a driveway paint booth.

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We're all in this together,
Emil
_________________
“…It's not just about what's interesting. It's also about what's helpful, and it's helpful even if it helps just one other guy working on a Ghia.”
kiwighia68

See my build on TheSamba at:
The K_R_A_K_E_N_N : a 70 Ghia Convertible reinterpreted

[viiking]

Evil_Fiz's explanation is a very good one.

But for me that is for a perfect external body paint job.

I would just look up Master Series/POR15 paint and look at their steps.

It is essentially a degreaser step, a rust converter step and a paint step.

For me, for the chassis and suspension, and with not wanting or affording to spend a lot of money on it I would do the following.

1. Scrape down the surface to get the bulk of the grease off. Degrease with auto degreaser. Repeat until clean.
2. Wipe down with a solvent. Even gasoline (when used safely) is better than nothing and relatively cheap. Do it outside and away from any ignition sources. Alternatively use, mineral spirits, white spirits, brake cleaner or xylene. This step is to get rid of traces of oils and greases.
3. Sand painted surfaces to give the paint a key
4. Treat rusty areas with a rust converter/Ospho. Follow the directions. Some do NOT need further treatment as they contain a polymer that seals the surface and prevents flash rust. Others like Ospho needs to be well neutralised with water (or an alkaline solution like bicarb) before painting Spot prime treated areas.
5. Spot prime bare metal surfaces. Allow to dry well.
6. Wipe down with solvent again. Wax and grease remover is usually a solvent like acetone or xylene.
7. Paint areas that are NOT accessible AFTER welding with weld through primer. If they ARE accessible AFTER welding, then just use normal primer.
8. Follow the directions for MS top coat.

In my case for the floor to tunnel area after welding, I was able to use a makeshift rotisserie from two engine stands so I could rotate the chassis. I was able to flood that area with paint with a little bit of viscosity reducer. Penetrol is something we have in Australia that you add to paint and it allows it to wick into gaps better than paint alone. I did one side in the vertical and left it for a day, then rotated and did the other. You'll have paint runs that you have to capture but you know it has got all the way through. If you have an area with too much leakage just plug the area with Play-Doh or plasticine or something that will slow it down, then treat those bits after the paint has dried sufficiently (i.e. take out the plasticine). Once all dry, seam seal.

Even if you do nothing more than convert rusty areas and paint with a good home steel anti-rust product you will have a good protection from most environments except salty roads.

I also tend to try and use stuff available at the big hardware stores rather than the specialist auto paint suppliers due to cost. Prior to retirement I used to assess MSDS as part of my job. Thousands of them. It is amazing to look up the MSDS for a lot of these special "wonder products" and find that they are nothing more than easily obtained residential products with a huge mark-up in price. The active ingredients are nearly always (other than proprietary secret ingredients) listed. It will either give you the actual name on the MSDS or a thing called a CAS (Chemical Abstract Services) number. Google that and you find out what is in it.

As an example I checked the first relevant MSDS for Brake Cleaner I found on the internet. Not sure if this is a brand you use or even available in the US.

http://docs.crcindustries.com/msds/5151.pdf

If you go to Section 3 " Composition/ information on ingredients" you see the composition as:

1. Acetone - 80-90%
2. CO2 - 10-20%
3. Toluene 1-3%

Acetone is the main ingredient. CO2 is the propellant (this being a spray can no doubt) and toluene in small quantities is just another solvent. So other than the convenience of using a spray can why would you not just buy acetone and put in a spray bottle to do the same work.

Now some people will say that all these extra goodies impart some other special attributes to do the job. Usually - no! In some cases there is and it relies on chemists to realise the reasons for this. In most cases is that someone can buy a certain chemical that just happens to have some other chemical mixed up with it at a much reduced supply price. Hence the company just formulates with that mixture and then has to declare it by law on the MSDS. The other reason that other things are added is to differentiate the product from their competitors. You don't want to copy someone else's formula exactly for fear of legal issues and if you add enough special woofle dust to the product you can bamboozle the mug out in the public who buys it.

Just go to a fuel distribution depot and watch the tankers arrive with all different company branding on them to fill up from the same storage tank. Is the fuel really that different?

Sorry for the rant and lecture.
_________________
1968 1500 RHD Lotus White Beetle since birth. In the hospital for major surgery
1966 Lancia Flavia Pininfarina Coupe - in the waiting room
Discharged: 1983 Vanagon, 1974 1800 Microbus,1968 Low Light,1968 Type 3

[Evil_Fiz]

@viiking
You just gave us some valuable information and gave me an idea. I am going to look up the MSDSs for several metal prep products and see how I can come up with a useful and affordable, big-box store available formula.

Thanks
-----
Emil
_________________
“…It's not just about what's interesting. It's also about what's helpful, and it's helpful even if it helps just one other guy working on a Ghia.”
kiwighia68

See my build on TheSamba at:
The K_R_A_K_E_N_N : a 70 Ghia Convertible reinterpreted

[viiking]

@Evil_Fiz.

Yes it is amazing how much information you can get from MSDS. It is also amazing how much mark-up is on some products sold to the public. I understand manufacturer's need to make a profit, but some of these are just price-gouging.

For example if you look at car-wash, dishwashing liquid and hair shampoo. The active ingredient that does all the cleaning is SLES/SLS (Sodium Lauryl Ether Sulfate/Sodium Lauryl Sulfate). The only differences are that shampoos have some ingredients like silicones to make your hair feel silky smooth and for car washes which have some minor anti-rust ingredients. I am not advocating using car-wash for your hair, but after armageddon I wouldn't hesitate.
_________________
1968 1500 RHD Lotus White Beetle since birth. In the hospital for major surgery
1966 Lancia Flavia Pininfarina Coupe - in the waiting room
Discharged: 1983 Vanagon, 1974 1800 Microbus,1968 Low Light,1968 Type 3

[Mike Fisher]

Wire brush vacuum degrease rust converter silver master series. If you want gloss put black master series on the silver.
_________________
https://imgur.com/user/FisherSquareback/posts
69 FI/AT square Daily Driver
66 sunroof,67,70,71,71,71AT,72,72AT,73 Parts
two 57 oval ragtops sold
'68 Karmann Ghia sold

Society is like stew. If you don't keep it stirred up you end up with a lot of scum on the top! - Russ_Wolfe/Edward Abbey

[oscarsnapkin]

[Mike Fisher]

Yes, you need rust converter on all the metal.
I don't wipe/wash it off & put the masterseries silver directly on top of the rust converter.
I've had better luck with the cheap siphon sand blasters that the pressure sand blasters.
Put down a big tarp & screen/reuse your sand.
_________________
https://imgur.com/user/FisherSquareback/posts
69 FI/AT square Daily Driver
66 sunroof,67,70,71,71,71AT,72,72AT,73 Parts
two 57 oval ragtops sold
'68 Karmann Ghia sold

Society is like stew. If you don't keep it stirred up you end up with a lot of scum on the top! - Russ_Wolfe/Edward Abbey

[oscarsnapkin]

[Mike Fisher]

My bottle is Rust-Prep but they all are real similar I think.
_________________
https://imgur.com/user/FisherSquareback/posts
69 FI/AT square Daily Driver
66 sunroof,67,70,71,71,71AT,72,72AT,73 Parts
two 57 oval ragtops sold
'68 Karmann Ghia sold

Society is like stew. If you don't keep it stirred up you end up with a lot of scum on the top! - Russ_Wolfe/Edward Abbey

[Busstom]

[Busstom]

OP, if you blast the parts yourself, I highly recommend that you invest in crushed glass bottles media. While more expensive, it's significantly safer than actual sand...do a web search for silicosis and to learn what happens when sand particles are propelled at hard surfaces at high velocity. Better yet, probably for a few hundred bucks, you can pay a local blasting servicer to do the work for you, you stay clean and safe while enjoying your time on something else.

[Evil_Fiz]