GB Modelli (aka Briga)

leichtes Sturmboot 39

This brief historical excerpt from feldgrau.net:

"The Leichtes Sturmboot 39 was essentially a small, high-powered assault craft used for river and small waterway crossings and assaults. They were also employed on security and anti-partisan patrols along river ways in occupied territories. Leichtes Sturmboot were very fast, able to achieve about 30mph with the use of an outboard motor extended from the rear of the craft. They were without much protection or firepower though, aside from the possibility of an attached MG at the bow of the vessel and the weapons of the men inside. Leichtes Sturmboot 39 were transported into battle by most German construction and assault engineer units and were used to spearhead river and small waterway assaults, usually in conjunction with an attempt to form a bridgehead for the construction of a bridge. The craft could carry 6 men or about a half-ton of weight. Hundreds of Leichtes Sturmboot 39 were built and used during WWII".

A preview of the kit along with instruction photos can be seen here on OTW.

With a mere four parts to the boat, construction is rather straight forward. Fit between the hull and transom was dodgy requiring much sanding, trimming and test fitting to get the parts to join without too much of a seam. Also, the transom plate was not to my liking, exhibiting a few sink marks. Practically all period photos I found lacked transom bumpers, so I decided to remove the bumpers and sand the transom flat. This also required removal of the bumpers that ran past the end of the gunwales. Plank lines were re-scribed and some scratchings with a hobby knife replicated wood grain. The floor boards are nice although there were small amounts of excess resin between the odd board that was removed with some scribing. A few tiny pinholes were discovered at the primer stage where the hull met the transom. These were easily filled with Vallejo Plastic Putty. The bar on the inside face of the gunwales has a square cross section. My reference picture (below) shows it to be wider with a rectangular cross section. So the kit's representation was cut off and replaced with some flat styrene rod.


It also looks to me like the kit's rib spacing is a tad too wide. Not having any proper plans to work from, I left the ribbing as is.

The motor is the weakest link. It is very basic and lacks a lot of detail. Below ia a list of changes/fixes perfomed:

• There were a few small voids in the casting that required filling.
• The prop shaft cover is incorrect. The kit represents it as two circular cross sectional pipes, of different diameters, with a step where they meet near the mid-point. Reference [3] shows what it really should look like, therefore I replaced it with a piece of stretched sprue which was subsequently shaped according to the walk around photos. The prop was removed to be added later, and its guard was also removed and added to my new shaft cover. There is a small plate at the end of the guard. The kit's version is much too thick, and incorrectly shaped, thus it too was replaced with a new one made from a small piece of plastic sheet

• The prop's blade shape is not the best. Unfortunately it was too small to attempt a scratch built replacement and I couldn't find anything small enough in my spares box.
• A pair of intake/exhaust heads are missing, so they were added from square plastic rod, shaped to match the curve of the crankcase. To them I added air/fuel mixture lines and exhaust pipes.

• On the underside of the shaft cover is an intake valve and associated piping used for cooling. These were replicated with stretched sprue, as was a pair of fuel lines on the underside of the gas tank.


• With disks punched from plastic sheet, bolts were added to the top of the crankcase, intake/exhaust heads, and added the absent oil filler/breather cap.

References

[1] GB Modelli web site (contains some useful period photographs)
[2] svsm.org (walkaround of the Kowats K4R4, Leichtes Pionier-Sturmboot 39 engine)
[3] wasserwacht-utting.de/chronik/ (Sturmboot 3-view drawing with dimensions)
[4] Waffen Review Band 84, 1. Quartal 1992, Journal-Verlag Schwende GmbH, Schwäbisch Hall, Germany p.31-52

Review sample supplied by Georgio Briga of GB Modelli (aka Briga).

GB Modelli (aka Briga) products are available at

Article Last Updated: 09 March 2022