painting over carc

[drjconley]

i want to repaint my truck. i have painted many vehicles, but never with carc. do i have to use carc for the paint to adhere? what other kinds of paint could i use? if i bead blast the paint do i need to be very worried about the carc dust?
thanks
jim

 

[gimpyrobb]

Dunno about painting, but YES you need to worry about carc dust.

 

[CUCVFAN]

As Gimpy said, CARC dust is not good for you. Prepping the surface is critical and some sanding will most certainly be involved. Be sure to wear a QUALITY respirator while sanding/blasting. You can paint over CARC with CARC, but you'll need to prime any bare metal with the correct (epoxy?) primer. CARC tends to let water through easily and if you paint it over bare metal, it'll rust quickly...

 

[drjconley]

if an epoxy primer will stick to carc, could i paint the entire truck with an epoxy paint. what types of paint have people used to paint over carc. how well did it work.
jim

 

[Evilone]

CARC MSDS Data

As the others have stated CARC dust, grinding/burning fumes are a hazard. Attached is more info - right click on and open link in new window.

 

[Jones]

CARC is a polyurethane so painting over shouldn't be a problem. Respirators are absolutely necessary to keep away from the dust which is highly abrasive and can promote silicosis.
I use a stiff-bristled brush and a pressure washer for surface cleaning and to get rid of any loose chips. Bare spots should be primed but it can be a good grade polyurethane primer.
My experience is that CARC is so rough that, once you get the surface dirt/grease and any loose stuff off, paints have no trouble sticking and any sanding necessary is just to get the bare metal spots to accept and hold primer/paint.

If you're painting over with CARC, priming with CARC primer isn't necessarily to get the CARC to stick; it's because the primer has the same properties and will also provide additional CARC protection if the top coat is scratched through or if there are any voids or missed spots.
Breathing CARC while applying is bad because the one part stuff is moisture activated and that can also be the moisture in your lungs. The older two-part stuff, uncured, is kinda like inhaling superglue.
Follow the S-W information sheets for application tips and procedures. An HVLP rig seems to be best to keep down on overspray and drifting clouds of CARC.

 

[gimpyrobb]

Sarge did a nice write up when he repainted his 820. Might want to look for that thread.

 

[Nonotagain]

CARC paint is a polyurethane paint with the addition of infrared pigments used to absorb different spectrums of light. It was designed to be able to withstand chemical decontamination in the event of nerve gas being used against US forces.

CARC stand for Chemical Agent Resistant Coating.

I test these materials for my day job.

Older CARC coatings used a primer system that contained lead, a lot of lead. If the primer on your truck is red, it’s Mil-P-52192 and contains lead chromate. If it’s yellow it’s the old zinc chromate TT-P-1757.

Of concern is the inhalation of chromium, as its now on the list of being a suspected carcinogenic. Federal law changed last year further reducing the permissible exposure to chrome. While a dust mask is better than nothing, you really should be using an air purifying or supplied respirator.

After sanding or spray applying these coatings wash your hands before eating or smoking. Wash all clothing in a separate wash cycle.

I hope this helps.

 

[wdbtchr]

What about touch up painting over CARC with nonCARC like you get from Rapco? Do you need to prime/sand the CARC to get it to stick or can you just clean and spray?

 

[Nonotagain]

What about touch up painting over CARC with nonCARC like you get from Rapco? Do you need to prime/sand the CARC to get it to stick or can you just clean and spray?

I'm not familiar with Rapco, but if the surface of your paint is not chalky you can clean the surface via power washing, then drying and apply an enamel top coat right over CARC.

If its chalky or you have loose paint or you have a lighter color showing through (the primer) its best to remove the coating down to base metal and start again.

 

[Duster06]

I'm restoring an HMMWV and the CARC paint is old but appears in good condition. Can I paint the whole truck over in truckbed liner without worrying about sanding off the CARC? Would a good wash be good enough prior?

 

[Confederate2348]

I'm restoring an HMMWV and the CARC paint is old but appears in good condition. Can I paint the whole truck over in truckbed liner without worrying about sanding off the CARC? Would a good wash be good enough prior?

I am about to do this to mine, would like to know how it went.

 

[98G]

I am about to do this to mine, would like to know how it went.

I've painted over CARC on 5ton trucks with good results. Just a good wash with green scrub pads. HMMWV is a little different though... but I'd guess it'd still be just fine.

 

[Confederate2348]

I guess i should make clear, I am about to bedline the exterior (i have lizard skin on the interior) with Raptor Liner. I have power washed a whole lot of crud off my HMMWV and wonder if i need to prep the old CARC coating anymore than just a good power washing prior to applying the bed liner?

 

[98G]

I guess i should make clear, I am about to bedline the exterior (i have lizard skin on the interior) with Raptor Liner. I have power washed a whole lot of crud off my HMMWV and wonder if i need to prep the old CARC coating anymore than just a good power washing prior to applying the bed liner?

You're posting about a hmmwv in the 5ton forum... so you're likely to get answers specific to 5ton trucks.

My experience in painting over CARC is that CARC is tough as nails and provides rust and abrasion resistance, while the overcoat of lesser paint provides cosmetic appeal. This has been my experience with steel substrate.

The HMMWV's aluminum and fiberglass shouldn't be much different since the interfacing surface will be CARC. Bed liner should adhere as well as paint.

If i were going to bed line one, I'd scuff it with scouring pads and then pressure wash it. This should provide a good surface for adhesion while still having more or less intact CARC underneath for rust protection.

Perhaps someone with bedliner specific and HMMWV specific experience will chime in....

Previous results -







(A couple of "after" and a "before" )

 

[Confederate2348]

Oh man, as you can see im new here, sorry about that, I was keyword searching for the info i was interested in and ended up here.

Thanks!

 

[71DeuceAK]

Re: the hazards of CARC paint, I also heard a story from someone who worked at BMY in the early '90s building M939A2s: Apparently, another byproduct of CARC fumes is cyanide...

Nasty stuff...Makes lead-based paint look tame or so I'm told.

 

[USAFSS-ColdWarrior]

Re: the hazards of CARC paint, I also heard a story from someone who worked at BMY in the early '90s building M939A2s: Apparently, another byproduct of CARC fumes is cyanide...

Nasty stuff...Makes lead-based paint look tame or so I'm told.

WOW! IF that's true, I'd like to see the MSDS (Material Safety Data Sheet) on the CARC product.

From my experience as an Aviation Avionics and Electrical Design Engineer:

For years the FAA "thought" by virtue of a wire manufacturing competitor's rumor that TEFLON INSULATED WIRE for aircraft would off-gas CYANIDE in a fire and therefore was threatening to ground ALL aircraft already certified as airworthy if ANY single wire onboard was TEFLON INSULATED. This would have had MULTI-BILLION DOLLAR ramifications on the entire aviation world. At that point there were MANY aircraft equipped with entire wire harnesses of this wire, largely favored by aircraft manufacturers because of it's lighter weight, comparatively smaller outside diameter for equal gauge strands otherwise insulated, higher abrasion resistance, and other favorable factors. Even when presented with the chemical formulations PROVING that those chemicals necessary to generate CYANIDE GAS simply and ABSOLUTELY were NOT PRESENT in the TEFLON PRODUCT, the "all-knowing" FAA still for many months/years perpetuated the FALSE RUMOR that TEFLON INSULATED WIRES involved in even the most minor fire would KILL everyone onboard the aircraft. As I recall, this "scandal" was finally squashed by a (threat of??) lawsuit including CIVIL PENALTIES for the persons refusing to acknowledge the science and TRUTH of the matter.

Just imagine if this was true about teflon. How many cooks have burned dinner while cooking in Teflon coated cookware?!?!?!?!? We'd ALL be dead by now!!!

Hence, while CARC is a very different composition than Teflon, PLEASE confirm whether this is FACT or MALICIOUS RUMOR before perpetuating this alarming claim.
Thank you.

 

[98G]

https://www.google.com/url?sa=t&sou...FjAAegQIABAB&usg=AOvVaw3kTXhJky7J3-NMbaeT14-j

And

 

[someoldmoose]

71DeuceAK, dunno where ya got the cyanide intel but it is false. The "guilty" parties in the dust / fumes are isocyanates ( think super glue ). This is what makes this coating stick "like glue" and be "tough as nails". Dupont had a similar (chemically) product under the Imron brand. Beautiful finish, hard as granite, deadly if inhaled or absorbed ( usually through the eyes or other mucus memebranes ). The primer was known "affectionately" as YELLOW DEATH. Also potentially deadly via the same routes during abrasion, stripping, or other means of removal.

The GOOD news : if it's in good shape, there isn't a better surface on the planet to paint over. As noted above, clean, no bare metal ( prime with epoxy ), and a little rough ( it's normal state is perfect, or roughen with 320 if shiny ). Once those conditions are met, spray, roll, brush, throw whatever you want on it.