Drill Bit Spring attachment

[BuddyC01]

Hello,
Been in the Covid bunker today sorting through boxes of things I unloaded from a Kennedy Rolling Chest I purchased. Had a lot of machinist tools and misc. Something I'd not seed before I could use an ID on. I can't quite figure out the purpose of this spring attachment on some drill bits in the box. Any ideas?

Thanks
BuddyC

IMG_20200404_132226 by Buddy Clark, on Flickr

 

[logical]

To help starting to back the bit out without it lifting the workpiece.

Sent from my garage.

 

[Lwel9226]

Depth gauge....

LW

 

[cvairwerks]

Drill Stop....limit drill depth or travel when going thru thin material with limited space behind the hole.

 

[rtz]

When you have a thousand rivets to drill out in a hurry and it would be very bad for the bit to punch through too deep. Aircraft skin on a in service aircraft for example.

https://www.browntool.com/Listview/tabid/344/CategoryID/101/Level/a/Default.aspx

 

[The Cobbler]

how big is the bit?
I'm sort of thinking fro drill pop rivet heads so the washer doesn't ride up the twist on the drill and they are a pain to get off

 

[cvairwerks]

Usually available from a #50 up to 5/16"...steel nose or plastic nosed.

 

[larry4406]

Learned something new for the day and its only 7:42 am here!