KP-21 a Surfacer?

[newbie]

Does the KP-21 really go on thick enough to act as a surfacer? I've been using all HOK products except my epoxy primer, (I've been using Nason, it's a 50/50 mix) only because I bought it first, and have had good luck with it. It mixes very thin, and doesn't seem to have any surfacing ability. I had a tank and fenders blasted, sanded, sprayed with primer, and even after sanding are pretty rough. Can someone recommend a good surfacing product that I could shoot over my primer. If KP-21 has surfacing abilities then I'l just shoot it over my Nason, and switch to KP-21 from now on.
Advise please.

My bike, my first paint job, couldn't have done it without this forum !!
My first paint job.
Thanks everyone,
newbie

 

[Bornhard]

A few years ago I bought some of that Nason 50/50 epoxy primer and used it on two jobs. After that I dispossed of the stuff and never completely used what I bought. That started me on my search to find an epoxy primer that worked for me.

I started to use KP-21 and feel it's one of the best out there on the market. Also I don't really recall the price, but it's close to Nason and much cheaper than Dupont's chroma primers (at least what the locals charge).

The thing with KP-21 is, you would be much better off spraying it directly to the substrate. If you spray it over Nason's primer it might eat into it a little too aggressive and cause it to wrinkle. It's happen to me, before I learned to read HoK's tech sheets. /ubbthreads/images/graemlins/foreheadslap.gif

What I like about kp-21 is the fact that it does fill in minor imperfections in the metal surface and when it's dry, it's extremely hard. You can sand it in about 4-6 hours with 80-180 grit paper. I sand with 80, if I get sags, or know I want to spray more on soon, 180 grit if I just want to make sure all is smooth on the surface. After all that I highly recommend Ko-Seal primer which has a great filling quality and is needed for a good solid color, before you spray your topcoat on. Ko-Seal is an easier sanding product, so sand with 400-600 grit paper.

There maybe other good sealers on the market, but KP-21 and Ko-seal have worked great for me and I seem to achieve results easier, faster and better with this combination.

 

[newbie]

Thanks Bornhard,
Maybe I'll use the Ko-Seal on this one over my nason, and switch to KP-21 if I do another bare metal. The tech sheet does say the KP-21 can be shot over a factory primer, so I assumed I might be OK on my nason. But then I remembered what a-s-s-u-m-e-d means, /ubbthreads/images/graemlins/lolsign.gif
Thanks,
newbie

 

[Bornhard]

in my experience KP-21 and Nason do not get along. KP-21 is really aggressive and can wrinkle up Nason primer. Not real sure if the Nason is fully cured for days and you apply KP-21 over it if there will be a prob though. I think there probably will be one though.

KP-21 is best of bare sheet metal, or parts you buy that are coated in an OEM (manufacture) primer.