question about primer

i checked the faq section, but still not sure. the problem is that i am using Tamiya Fine Surface Primer (white) spray can, and i spray my wrx over 5 thin coats, but I can still see the blue base molded color, and the surface is so rough. I tried to sand with 2000 paper, the surface was smooth after that. But once I spray more primer, it becomes rough again.
1) am i doing something incorrectly?
2) should i stop primering after sanded and smoothed ? (i.e. but after I sanded , I can see the base blue color

1) Not really, except that you should have used gray for the first few coats, before white primer. There are only few white primer that can hide the color of plastic, and as you know, Tamiya white primer isn't.

If the surface looks like a sand paper, the primer must start drying before it reaches the object, so you can shorten the distance just a little. If it's too close, it would cause the orange peel effect, so be careful.

2) Sand and remove white primer as much as possible, then use gray for one or two coats, then use white primer. Or use one of those paint remover to completely remove primer.

thanks for your info. I used Grey primer years before , and grey primer is very smooth......but white primer is very rough........do u have similar experience?

not me, my white primer went on smooth... but i didnt use the tamiya brand...

I've had the Tamiya white primer come out very smooth before. Try variing the distance you spray from, like Hiro says.

Does'nt grey primer make the color look darker?

yea tamiya white primer came out really smooth for me, when i fucked my car

i had to send the whole thing.. but of coures mines not liek glossy smooth

tamiya primer works really well so far, for me

yeah. I agree, it seems the primer was dried before it landed on the body, so I will shorten the spray distance tonight, hope it works....... :(

how fine sand paper should I use to sand the primer? 1000? 1500? or 2000? pls help.......I am really stuck by primer.......