Paint without Hardner

[72 Challenger]

When I bought my car I was given ~1/4 of a can of the exact paint that was used to paint my car. I was told it does not have hardner.

Can I just buy any hardner or is it specific to the paint? I have a few touch ups I want to address. small stuff like the single stone chip, a small scratch where the trunk spring is mounted, chip where the jack hold down is etc...

I also know squat about paint and body so how much hardner do I need?

[JS29]

single stage? what brand is it, some brands don't mind off brand additives. I like to stay with the same company's product's. you will also need reducer as well.   

[Cuda Cody]

If the paint is a 2 part then it will not harden without the correct activator (hardener).  Does the can of paint have a label or name?

[72 Challenger]

If the paint is a 2 part then it will not harden without the correct activator (hardener).  Does the can of paint have a label or name?

This is the only part off the can that is not in french or covered by paint/ decals

[RUNCHARGER]

It looks like Omni. About ten years ago I would buy generic hardner and it worked with everything. Things today are much more finicky though.

[Moprr]

I would find a local PPG dealer and take it there, they can set you up with the proper hardener then you know your safe.

[Cuda Cody]

Yes, that is omni and any PPG dealer will be able to get you the correct reducer and hardener.   MTK is mixed at 4:1:1.  4 parts paint to 1 part reducer to 1 part hardener.  The hardener is either MH167, MH168 or MH169.  The number is the speed it will flash off....  MH167 Fast, MH168 Slow, MH169 Very Slow.

https://ppgrefinish-na.uberflip.com/i/355535-omni-paint-system-catalog/9?

http://www.englishcolor.com/ECS_-_ECUCITC/LIC_CPC_files/MTK%20TDS.pdf

[72 Challenger]

Just to make sure. I REQUIRE reducer?

If I were to bring the can to a paint shop could they make this formula in a spray can?

[Shane Kelley]

If you are just dabbing small chips you don't need reducer. The thicker the better for doing that.  To be honest I do touch ups all the time without hardener. It will dry. I wouldn't do anything large, just small rock chips.. 

[Cuda Cody]

Yes, some paint shops can put that in the can with the reducer and hardener.  It'swill be about 3 to 4 oz of paint and once you use it the can will go bad in about 24 to 48 hours.  So it's a one time use, but the quality will be fantastic.  If you just need a rock chip dabbed then try it like Shane does and see if that works first.

Just to make sure. I REQUIRE reducer?

If I were to bring the can to a paint shop could they make this formula in a spray can?

[72 Challenger]

This exactly the information I was looking for.

Thanks guys! 

[Rumple]

If you are going to use hardener you will need the correct one. 2K PolyUrethane paint is a chemical cure - hydroxyl groups on the paint side react with isocyanate groups on the hardener side to form a PU. Lacquers dry by evaporation and enamels by evaporation and some light bonding.  Think of the paint and hardener components of a 2K PU as pluses and minuses.  Ideally you want each + from the paint side to tie up with a - from the hardener side. Not all paint formulas have the same number of pluses in a given volume.  Same goes for hardeners, so you should follow the manufacture's mixing instructions.  Adding too much or too little hardener can result in a poor finish.  From soft/cheesy to brittle and loss of adhesion.
It's common for companies to offer urethane hardener as an additive for enamel finishes.  In cases like this the hardener isn't bonding with the paint, it's actually reacting with itself and trapping paint particles in a disorganized network.  It's slightly harder than an enamel, but not nearly as hard or chemically resistant as a true PU.

[RUNCHARGER]

Great explanation Rumple!