priming?

Howdy. The primer is always a good thing as fare as paint having a better bond. Pluss you get to see what dosent look just rite. When you say enamel I asume you meen a oil based paint. Acrylic / watebase also hase a enamel ( shiny paint) if the finnish is runny your first cote should be more of a light cote then depending on paint directions for recote time youcan start putting on heavy cotes. That first light cote should help hold it.

We all spray or brush different so be carefull. I have bin painting for 30 pluss yrs that's how I look at it. I hope that helps out

Does the primer matter depending on enamel or acrylic? I tried using acrylic and it seemed very watery with tamiya paint, I'd always used enamel as a kid and was used to it sticking right away.

You must not be doing anything wrong if the paint isn't liting. MM Acrylic seems to work better when I made a homemade thinner with distilled water and 70% rubbing alcohol, along with a retarder. Seemed to bite better.

Yes, I always prime any large part, whether I will be masking on it or not.  And certainly any assemblies that have seams that I will be smoothing.  The only thing I don't prime is sometimes I will hand paint very small parts without primer.

Fly-n-hi

Are you using Model Master Acryl?  It's notorious for lifting.

Yes, I was using MM on that one. Had some comments same as yours re the MM after the incident, but I didn't want to post a negative towards MM with my level of inexperience. :)

Switched to Vallejo and Tamiya, have done some minor masking on my current build. No primer on this this one due to intricate panel lines, no lifting so far. Fingers crossed, and thanks for the heads-up, Fly-n-hi.

I generally use Tamiya...and have had really good luck with no primer and no lifting at.

Are you using Model Master Acryl?  It's notorious for lifting.

Really can't resist jumping in on this one.

My last build (which was also my first build back after a long hiatus and my first attempt at using acrylics) was also my first masking attempt (that I remember, anyway).

I did some some dumb things. Including NO cleaning/prep after a LOT of handling, and very stupidly using blue painters tape (not even de-tacked). Here's what happened.....

I don't have enough experience back to be giving advice, but this is what can happen with no priming and/or improper surface prep. I've heard many experience folk here comment that surface prep is as important, if not more so, than priming. Though for me, next time anything that will be masked extensively will have a primer with some bite.

Never used a primer and never had a problem, that's with both enamels and Acrylics.

Sorry guys and ladies..didn't see the other post below mine.. It looks like I may be using primers for sure if I use acrylics.......Thanks

yes, definitely clean your model before painting (iso alcohol, windex, at least soap and water) and then a light primer will help acrylic paints stick down