German Sd.Kfz.7 Mittlere Zugkraftwagen 8t early version
Trumpeter 1:35 Kit #01514
German Sd.Kfz.7/1 2cm Flakvierling 38 auf Selbstfahrlafette
( early version) with Sd.Anhanger 51

Trumpeter 1:35 Kit #01526
German 3.7cm Flak 37 auf Selbstfahrlafette
(Sd.Kfz.7/2 late version) with Sd.Anhanger 52

Trumpeter 1:35 Kit #01526
Drive Sprocket Modifications:

The main issue with the kit drive sprockets is the drive rollers are not offset as they should be but are located centrally on the outer sprocket facets which is very noticeable on these larger sprockets and prevents the track from sitting flush around the sprocket.

Assembled drive sprocket as it comes in the kit with the etched step ring.
Note the lack of drive sprocket teeth offset which prevents the track from sitting evenly around the sprocket.

Actual drive sprockets for reference

With a little work it's possible to modify the kit sprockets to allow the drive rollers to be offset correctly and in turn allow the track to sit evenly around the sprocket, thanks to Bernard and Peter for the feedback.

The drive roller ring (part B15) has small brackets included that fit into the corresponding recesses in the outer drive sprocket half and the first modification is to carefully cut these brackets from the sprocket ring using a very sharp knife or scalpel blade. These brackets should be saved if possible to re-attach to the outer sprocket half to ensure the gap around the outer rim of the sprocket is the same as original.

Modifications to the kit sprocket roller ring and drive sprocket as per text.

The small brackets are then glued to the inside of the outer drive sprocket (part B21) in the same position they would be if still attached to the sprocket ring, test fit the sprocket ring before cutting off the brackets to note the position.

Brackets cut from the sprocket ring glued to the outer drive sprocket

The modified drive roller ring can them be fitted to the outer drive sprocket with the drive roller offset aligned correctly, you can also position the ring with the detailed side facing outwards to further add to the detail instead of facing inward as it comes in the kit. Before adding the inner sprocket half (part B1) cut away the small locating pin inside the locating boss to allow this to be aligned correctly with the outer sprocket.

Modified sprockets showing the correct drive roller offset and the
track sitting flush around the sprocket as it should.


You should note that the drive roller is located forward on the sprocket facet on both left and right sprockets so they are facing forward when fitted to the vehicle and so are not the same on both and you should insure you align these appropriately for each sprocket.

This corrects one of the main issues with the kit sprockets with the only remaining issue being the six engraved lines on disc face which is another challenge.

Return to reviews:

Page created April 27, 2009