I have a couple of styles of Stanley Bit Gauges that I thought may be of interest to folks using auger bits. These are Stanley #47 and #49 Bit Gauges. Essentially they attach to your auger bit and indicate when to stop drilling. The #47 has a spring that flexes when it reaches the desired depth. The #49 has a couple of wings and will not let you drill any further.
Keep your eyes open for these guys if you happen to be out rust hunting…
Stanley #47 Bit Gauge
Stanley #49 Bit Gauge
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