Cheap Depth Stop Drill Bit
What you need:
1 Drill bit, size needed
1 Roll of tape, Duct, Masking, Electric, etc.....
If you are drilling a hole that you do not want to go to deep. You can purchase a drill bit with a collar or you can use a cheap trick to prevent it from going deeper then you want it to go. Determine the depth of the hole that you want to drill. Measure it so that you are exact, measure it again so that you are certain. Now that you know what depth you want to drill take the drill bit that is in the size that you need and measure up to the max depth you want to drill and wrap it with tape, enough tape to make a thick collar that will stop you from going past your measurement. The tape does not matter as long as it sticks good, we prefer electric tape, but masking tape works good too.
If you want to drill a 3/8 hole that is a 1/2 deep. Take the 3/8 drill bit and measure 1/2 inch up the drill bit from the tip. Mark and start wrapping your tape at this point around and around until you have a thick stop.