Dumb Question 1.
When modellers talk about all over washes is the entire model covered in the wash?

Dumb Question 2.
If this is correct how long after this process are spot or pin washes conducted.

I always seem to get them ugly tide marks and when I try to clean them up or layer them off I stil have low tide . I mostly use Tamiya acrylics and oil for the wash.......

Any help to solve this headache of mine will be most welcome

IMHO, the overall wash is an invitation for disaster promulgated by one of the major modeling magazines. Far more effective, again, IMHO, is placing a small amount of thinned paint where you want it, in panel lines, at sharp junctures or at the base of raised details. Acrylics are much more difficult due to the size of the pigment particles and issues with surface tension. Artistt oils are the best and enamels a close second.

Hi Dan,
As Al points out,overall washes CAN be a disaster.
They usually go wrong on 2 key points.First,the wash is too color strong.This is where the tide marks start jumping out at you.The wash should be 5% color/95% solvent(I use enamels or W&N water mixable oils).Most of what I have read from other modelers states that acrylics do not do well in washes for one reason or another.The second wrong turn comes from not taking care of the tide marks while still wet.It's easiest then.
The wash should look like slightly dirty solvent and applied rapidly with a soft #4 or larger brush.Start at turret top and work down,all around.On 1/35 scale builds,this is less tha 2 minutes time.Now, with another large,soft brush,soak up heavier areas of color or apply clean solvent to spread the color to desired spots or areas.Color will be more pronounced when dry,so lighter is better.You will use lots of solvent,don't skimp.Ventilate the area very well.As it drys,you can adjust and vary the color load to suit.It takes about 3 days for a oil or enamel wash to be hard enough for another similar go.Spot,or pin washes can be applied sooner if using a differant media like ink or water based.2 days or so later,you can apply another hotter wash over that.
Base coat should be dry for at least 3 days before any wash.
Sorry to be so long, but this is how I do mine.It's just not a short process.
cheers!

Thanks for the tips will give them a go on some older kits.