Strong Soft Soap

Linseed-oil soft soap is a concentrated alkaline detergent dissolving all fats. It contains no toxins or phosphates.

Available in 1- and 5 litre tin canisters. Where to buy.


Download the work manual in PDF here or read it below. 

The Technical Data Sheet and the Safety Data Sheet are under the heading Datasheets in the main menu.


Very tough dirt/grime; engines, etc.: brush the surface with STRONG SOFT SOAP and let it sit for a while. Use a dish-brush on the dirt/grime. Rinse off with water once the dirt/grime has dissolved. Repeat if necessary.

Tough dirt/grime: dilute STRONG SOFT SOAP to 50 % with water or until it can be sprayed using a hand-held sprayer. Spray liberally on the dirty surface and let sit for a while. Remove the dirt and grime, then rinse off.

Light dirt/grime: dilute the STRONG SOFT SOAP to 1/100 and apply. Let sit for a while and scrub with a brush or rinse off using a pressure washer.

Brushes with linseed oil or linseed-paint on them: cover the brush with STRONG SOFT SOAP and knead it. The soft soap thins and/or is tinted. Rinse with water. Then squeeze the water from the brush and cover once more with soft soap. Repeat until the soap no longer thins and/or is tinted.

Let the brush dry thoroughly before using it again with Selder & Co’s paints or oils.

Dried linseed oil or linseed-oil paint leftovers: soak the workpiece in undiluted STRONG SOFT SOAP until the dirt has softened and can be removed. This may take several days.


STRONG SOFT SOAP dissolves linseed oil paints and attacks aluminum.


Use gloves when working with STRONG SOFT SOAP, as it dries out the skin. Mind your eyes, as STRONG SOFT SOAP is a potent irritant.