Translations:Poelito - Poêle de masse semi-démontable/250/en-gb

• Once in place, put small blobs of clay mortar onto the junction where the fins and masonry meet, spreading it out gradually until it is all covered. This prevents the sand leaking out of any spaces between the fins.

Clay mortar: clay soil (which is sticky) and sand in variable proportions. Generally, 1 part clay to 3 to 5 parts sand, with enough water to make balls that hold and stick . If it is used for sealing or as masonry, it is best to ensure you have the right proportions. However, in this case, this is not important.