Here are my experiments with magnetising one of the new Kratos tanks from Games Workshop for Warhammer 30K or 40K.
Magnetising the dozer blade came first – I did this after assembly, though it’d be easier to do it beforehand. Taking a power drill to the built tank was somewhat hair raising – if you do this be careful that the drill doesn’t bite the plastic and pull sharply into the hole. I went with 6x1mm magnets as a decent fit, and they are enough to hold the blade up:
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I picked the outer aspect of each mount point on the chassis, as there was more plastic at that point on the blade mounts to drill into.
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On the blade:
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It doesn’t look it from the angle of the photo but the magnets are only just sitting higher than flush to ensure good contact with the other side.
Magnetised and in place:
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The body guns don’t strictly need it as the guns push fit into the socket, but… well, I got a bit carried away. 5x1mm magnets – done before assembly:
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More to come!