Bare metal is always best cleaned with 700-1 Waterborne Wax and Grease Remover and then let it sit 60 minutes before applying the epoxy! After first reading our Epoxy Tech Sheet mix enough SPI Epoxy Primer to spray 2-3 wet coats over the entire car. Spray one wet coat and let flash about 30 minutes then apply a second wet coat (3rd coat is optional). Let the epoxy sit overnight then apply body filler or glazing putty over the epoxy. Let the epoxy sit 48 hours before applying polyester primer. It is not necessary to sand the epoxy before applying the fillers (within the first 7 days
of spraying epoxy) as they will bite into the epoxy and feather great. When you have finished sanding all the bodywork you are likely to have some bare metal spots from sanding. Spray one wet coat of epoxy over all filler spots and over any bare metal spots.
Now let the vehicle set overnight.
Before spraying 2K primer, all bodywork should be checked to be sure there are no pinholes or low spots that need filling with body filler or polyester putty. If additional filling is necessary, it should be done at this stage, and another coat of epoxy should be applied.
Now let the vehicle set overnight
The next day you can start spraying the 2K primer over the epoxy. Once again, it is not necessary to scuff or sand the epoxy before applying primer. The most important thing to remember at this point is spray one wet coat of 2K primer and let it sit for 5 minutes before applying the second coat. Follow this procedure between all coats of 2K Primer. This step when abused messes up more paint finishes than anything else! When all the primer blocking, and any necessary primer repairs are finished it is always best to use the epoxy as a sealer. Mix up enough epoxy to go around the car with one wet coat and adding a double shot glass of SPI 885 Urethane Reducer per quart. Let the epoxy sit for 30 minutes. Stir one more time and strain. Spray one full wet coat of epoxy over the entire car. The epoxy should sit for 6 hours before spraying basecoat, the best option is let it sit overnight.
In bold is my proposed addition to the "Spraying Primers" section. I don't know if such a change would even be wanted, but I do think it is worth discussing. If it is found to be desirable, I'll edit the post as we go when changes are recommended. Perhaps then the amended procedure could make it into a future version of the Tech Manual.
The reason I am proposing this change is it is becoming apparent that people following the perfect pant job procedure are often moving to 2K urethane before the bodywork is actually done, then filling on top of the 2K. This is not best practice, and should be discouraged, in my opinion.
I wanted to keep the addition as short as possible, but some things are left out, like how the checking gets accomplished. Typically I would say it gets checked by blocking with 150/180/220, but that might require going to 2 coats of epoxy beforehand, which could create a problem for people at lower temps.
I'd really like everyone's feedback on this.