Get a set of these;
I got the set on a flea market for a couple of euros but they are available online, as a set or single sizes...also ones for cutting squares/rectangles
Just put Leather Hole Punch into search.
For the basing material, I used old neoprene cutting matts*
If you can, you can make your own. Length of Steel pipe with the wanted diameter and file the outer side sharp. Works..I´ve tried it
PS. The one 3rd from the left is 20mm which I use for basing infantry.
*I´ve altered my basing method slightly so don´t need so many discs
2cm diameter plastic Discs. Nags or small groups of bods generally get put onto 3.5cm Diameter ones.
From left ot Right
1. A mix of sharp sand and PVA gets added. Any blank spaces on the bods actual base gets thinned out PVA dabbed on and then a sprinkle of sand gets added. This is then left to dry.
2. Base painted with dark brown, left to dry.
3. Highlights with mid brown and static grass applied...again using PVA.
4. After a drying period of about 24 Hours, the new base is prised off the plastic disc. A thin blade such as a stanley knife is good for this. The new base gets stuck onto some thin card using..again, PVA.
5. Excess card trimmed off and the visible edge of the card gets painted .
Swopping them from the Neoprene base to the thin card brings them closer to the table surface