Here's some information I've got from Göran Helmer (former salesmanager of Marieholmsbruk) ; The keel ballast for the IF is 1.250 kg, i.e. 58%. For the IF E with inboard engine the keel ballast is cut off at the end of the ballast. Believe some 150 kgs were cut off in order to compensate for the eng...

As far as we know, here in Holland some or maybe all IF's were originally delivered with cap shrouds of 6 mm.

In the class rules a size of 5 mm is mentioned for cap shrouds. I suppose this is the minimum, but how long does it last ?
Is 5mm safe enough at the long term ?