Scribe plinth

[fabgav]

I am ashamed to ask this but I can not figure it out.

My plinths are 220mm (Ikea - yes yes I know I know) the plinth gap is varying around 150mm with an un-even floor.

How do I scribe in one go so that I get the correct scribe and height?

Find the lowest point say 140mm.
220 - 140 = 80mm, set a compass to 80mm then fit the plinth infront of cupboards level to the highest point, and scribe with compass set to 80mm?

 

[foxhole]

You can cut to shortest dimension , the top is not seen as it sits back under unit , any gaps will allow ventilation.

 

[Harbourwoodwork]

I am ashamed to ask this but I can not figure it out.

My plinths are 220mm (Ikea - yes yes I know I know) the plinth gap is varying around 150mm with an un-even floor.

How do I scribe in one go so that I get the correct scribe and height?

Find the lowest point say 140mm.
220 - 140 = 80mm, set a compass to 80mm then fit the plinth infront of cupboards level to the highest point, and scribe with compass set to 80mm?

put the plinth on the floor in front of the base units make the top edge parallel with the bottom of base unit,use wedges to hold it at the right height, measure the distance you want it to drop to clear bottom of the base units,cut a block of wood the same dimention(say the end of a 2"x1") use that as ascribing block run that across the floor infront of the plinth with a pencil on top that will give you a perfect scribe