Question on painting the underside of a chassis...

[Bill Anderson]

Hi !

I'm finally building the Revell '68 Dodge Charger R/T, and just finished the two motors - which imo came out pretty nice.

My next step is to spray the body color - which will be a Testors Graphite Grey Metallic.  

In all my years (began building in late '50s) of putting together car kits, I've painted the underside of the chassis a flat black.  But the instructions for this kit indicate using the body color for the chassis.

Did any prototype production cars do this?   Is this a new trend for proto customizers or model builders?

What is your take on this.......should I paint the chassis the body color, or the typical flat black?

Thanks all for your input!

Mobilman44

 

[atomicholiday]

I can’t speak for that specific car, but I think most factory stock vehicles back then were either black or red oxide, with body color over spray at the edges.

 I usually do a google search like “68 charger undercarriage” and look at the pictures.  I’ll go with whatever I see the most of.   
Hope that helps.

[Dave G.]

Same here, don't know the specifics of that car but most undersides in the 60's, especially unibody cars, were some color primer with body color over spray. Most were an oxide or some tone of gray as I recall. I still do them black quite a bit though because being here in the NE we often saw black undercoat on a lot of cars.

[MrObsessive]

MOPARS of that era that I've seen used a gray primer for the chassis (Ford loved red oxide primer), but depending on where the car was sold, and what dealer it ended up in, it could have been sprayed with a black undercoat to retard rust.

When I did my '69 Charger Daytona years ago, I remember using a gray primer on the underside, as that's what MOPAR aficionados said that's what came out of the factory, and then spraying the edges with the body color. There was no robot painting in those days, so it's highly doubtful you saw the entire underbody of the car painted like you see today.

Hope this helps!

[Dave G.]

By the way the primers were applied in an electrostatic dip. It didn't look like sprayed primer as such. Over in the 1/1 Mopar forums they speak of this, then the body went on a rail system about 9" off the ground and that got painted the cars color. Apparently not a ton of over spray hit the underside floors around 1968. I imagine it was an automated spray system.

[StevenGuthmiller]

This subject has been batted around a lot, and I believe that for Mopars, the consensus is what Bill Geary suggested.

Gray primer with a little body color around the edges.

 

Another aspect to consider is the chassis components.

By this I mean the frame rails, cross members, etc.

These are the areas where you usually see the most "mistakes".

 

I'm no expert on this subject, but from what I've been able to learn, apparently these cars, being of uni-body construction, had the entire frame in place at the time of body painting, minus the suspension components of course.

A common mistake, (I've made it myself) is to paint the rear or front frame rails black.

My understanding is that they would all be primed and over sprayed just as the rest of the floor pan was.

The only parts that would have been painted other colors would have been the suspension components added later, such as the front K-frame, torsion bars, exhaust, fuel tank, rear springs and axle, etc.

 

Another detail that I became aware of while researching my '68 Dodge Coronet project, (which I used the Revell '68 Charger chassis for) is that at least some of these cars had limited undercoating applied to certain areas of the chassis pan.

Mainly a smattering inside of the front and rear fender wells.

 

Of course you can avoid all of this by just painting the entire chassis with a thick, lumpy satin black to simulate the undercoating installed by a lot of dealers. ( Not certain if the factory offered full undercoating or not. I never researched that).

 

Anyway, I think I got pretty close to the correct look for my Coronet, although my understanding is that there may have been variations based on where the car was built.

 

This is the exact chassis that you'll be dealing with, with a few added "Hemi" mods, including front and rear torque boxes, and front K-frame "skid plate".

And of course, it's been lightly weathered.

 

 

 

 

Oh, and by the way, Mopars of this era always had all of the sheet metal engine compartment components painted in body color as well.

 

 

 

 

 

 

Steve

Edited April 27, 2023 by StevenGuthmiller

[atomicholiday]

1 hour ago, StevenGuthmiller said:

This subject has been batted around a lot, and I believe that for Mopars, the consensus is what Bill Geary suggested.

Gray primer with a little body color around the edges.

 

Another aspect to consider is the chassis components.

By this I mean the frame rails, cross members, etc.

These are the areas where you usually see the most "mistakes".

 

I'm no expert on this subject, but from what I've been able to learn, apparently these cars, being of uni-body construction, had the entire frame in place at the time of body painting, minus the suspension components of course.

A common mistake, (I've made it myself) is to paint the rear or front frame rails black.

My understanding is that they would all be primed and over sprayed just as the rest of the floor pan was.

The only parts that would have been painted other colors would have been the suspension components added later, such as the front K-frame, torsion bars, exhaust, fuel tank, rear springs and axle, etc.

 

Another detail that I became aware of while researching my '68 Dodge Coronet project, (which I used the Revell '68 Charger chassis for) is that at least some of these cars had limited undercoating applied to certain areas of the chassis pan.

Mainly a smattering inside of the front and rear fender wells.

 

Of course you can avoid all of this by just painting the entire chassis with a thick, lumpy satin black to simulate the undercoating installed by a lot of dealers. ( Not certain if the factory offered full undercoating or not. I never researched that).

 

Anyway, I think I got pretty close to the correct look for my Coronet, although my understanding is that there may have been variations based on where the car was built.

 

This is the exact chassis that you'll be dealing with, with a few added "Hemi" mods, including front and rear torque boxes, and front K-frame "skid plate".

And of course, it's been lightly weathered.

 

 

 

 

Oh, and by the way, Mopars of this era always had all of the sheet metal engine compartment components painted in body color as well.

 

 

 

 

 

 

Steve

That undercarriage looks spectacular.  Really nice use of panel liner or wash.  Looks great.

[Bill Anderson]

Thank you all!   I think I'll do a dirty grey primer with some body overspray around the edges.  

Thank you again!!!

 

[my66s55]

I think it comes down to what you are trying to create. I've been building model cars as long as you have, maybe longer. Having grown up in suburban Detroit, I am totally aware of what the underside of an auto looked like as delivered from the dealer.The undercoating put on by the dealer would need a flat black color to make it right as delivered in certain area of the country. Straight from the factory to the dealer would be the body color.