I took a gamble and purchased a non iso 2k high build primer kit from ebay that uses valspar ud429 convertor instead of 2k hardener. I have mixed it as per instructions given at 4:1 with 10% 2k thinners. I have left it 2 days and it still hasn't dried correctly. I have googled valspar ud429 and the spec sheet states 2:1 mix, has anyone tried this stuff as I was Hoping to avoid an airfed mask but not looking good so far. Only tested it on a spare panel so no harm done but am a little concerned after spending best part of £40 on what appears to be an expensive mistake. May bite the bullet and get some hardener and airfed mask but not sure if my 3hp compressor will feed both mask and gun. Any advice welcome.