Wagon bulkhead
The wagon bulkhead is a specific way of cutting wooden planks with standing growth rings. Although the term appears to be a noun by its constituent parts, it is commonly used like an adverb.
The term originally comes from carriage building , but has only been used in wooden shipbuilding since the beginning of the 20th century . As with the rift cut , a plank cut from a wagon bulkhead is mainly sawn radially from the log. Since wood shrinks more in the plane of the annual rings than perpendicular to it, a plank cut into a wagon bulkhead is more dimensionally accurate in width. This means that it hardly throws itself and does not bowl like boards with horizontal annual rings that usually develop a slightly concave-convex cross-section. Softwood boards cut from the car bulkhead are suitable for use as floor boards , as they do not have any leaking annual rings that can come off as a result of the load.
When planks cut into bulkheads are used in shipbuilding, the width of the joints between the planks changes less with changing wood moisture. This improves the tightness of the caulked trunk.
Commercially available boards or planks are made by cutting a tree trunk into a pile of boards with a gang saw . In the majority of the boards or planks cut in this way, the annual rings lie flat or at an angle to the flat side of the boards. Only the middle boards of the stack are cut into bulkheads. If the goal is to obtain boards that are mainly cut from bulkheads, only the middle boards may initially be sawn from the trunk. The remaining pieces on both sides of the outside must then be turned 90 ° and sawn again. Other and more complicated options also exist.
literature
- Curt W. Eichler: wooden boat building. Heel Verlag, Königswinter 2004, ISBN 3-89365-788-6 , pp. 41 and 222.
- Adolf Brix: boat building. Edition Maritim, Hamburg 1990 (reprint of the 7th edition from Verlag Wilhelm Ernst, Berlin 1929), ISBN 3-89225-382-X , pp. 14 and 200.