1K and 2K Compatibility/Incompatability

[Moparfiend]

I know there are so many formulations of primers and body fillers and but are 1K primers generally incompatible with 2K products in general?

 

[Canadian1968]

1k and 2k - 1 part or 2 part products . The 2k product is one that requires a hardener to cure properly. It also means the product has crosslinking on a chemical level that makes it considerably more durable and stable compared to a 1k product. To answer your question , yes they usually compatible with one another but you will sacrifice durability and over all performance with the 1k. Example you have are prepping a car for paint and you notice a small in perfection that requires a small amount of 2 part putty. You decided to use a 1k aerosol can to prime the spot for speed and just over all convenience. After car is painted you notice that spot showing up ever so slightly. Maybe it sank and you can see the sand scratches or it ringed aroubd the repair. It's doesn't mean that it was't compatible BUT because it was 1k product and can basically be washed off it is much more open to have problems occur . Bottom line professioal results = 2k nice results with some possible flaws less durability, cheaper = 1k

 

[Moparfiend]

1k and 2k - 1 part or 2 part products . The 2k product is one that requires a hardener to cure properly. It also means the product has crosslinking on a chemical level that makes it considerably more durable and stable compared to a 1k product. To answer your question , yes they usually compatible with one another but you will sacrifice durability and over all performance with the 1k. Example you have are prepping a car for paint and you notice a small in perfection that requires a small amount of 2 part putty. You decided to use a 1k aerosol can to prime the spot for speed and just over all convenience. After car is painted you notice that spot showing up ever so slightly. Maybe it sank and you can see the sand scratches or it ringed aroubd the repair. It's doesn't mean that it was't compatible BUT because it was 1k product and can basically be washed off it is much more open to have problems occur . Bottom line professioal results = 2k nice results with some possible flaws less durability, cheaper = 1k

Thanks what I am working on right now is beginning bodywork and have some area’s that I used a rattle can 1K self etching primer over some metal worked areas. Should I strip it then re-prime with 2K or can I prime OVER the 1K with the K?

 

[snakeoil24]

Strip it

 

[Canadian1968]

I am not a fan of aerosol etching primers . I am sure there are some better than others though. A common mistake people make is using the etch as a regular primer. It's not ment for build or even rust protection actually . The purpose is "etch" itself into metal and provide excellent adhesion for your primer / surfacer to bit into . The primer is what should contain your anti-corrosive properties. I personally like an etch WIPE . Bondrite etch wipes are what we use at work and what I use for any large metal areas . Look at the 2k primer you want to use if it is a DTM (direct to metal) I would be temper to wash off the aerosol and prime as needed . Always check the TDS for the product your using its the ultimate answer to your question .

 

[Moparfiend]

I am not a fan of aerosol etching primers . I am sure there are some better than others though. A common mistake people make is using the etch as a regular primer. It's not ment for build or even rust protection actually . The purpose is "etch" itself into metal and provide excellent adhesion for your primer / surfacer to bit into . The primer is what should contain your anti-corrosive properties. I personally like an etch WIPE . Bondrite etch wipes are what we use at work and what I use for any large metal areas . Look at the 2k primer you want to use if it is a DTM (direct to metal) I would be temper to wash off the aerosol and prime as needed . Always check the TDS for the product your using its the ultimate answer to your question .

Thanks the TDS doesn’t always have compatibility information. I will take it off just to be safe. Its a small area anyway.

 

[Canadian1968]

Well actually it will .

It should tell you the allowable substrates .

Sikkens waterbased primer cannot be put over polyester putty .

SPI epoxy primer does not recommend an etch primer .

and so on. But I think you have already made the right decision to wash it off