Odd bit holder

[DFB]

Anybody have any idea what the original purpose of this bit holder may have been? Its something I had in with my metal working drawer of drill bits, files, reaming and tap tools.

Where it came from I don't recall. Maybe came out of the old electronics manufacturing plant way back when and was used on some assembly job there

The threaded mandrel is very similar to one for like a hole saw with the set screw to hold the bit, but it's not the right size. At least not for the saws I have. The hex shank portion must have been for a chuck though I would say

Wondering is it something out of the old machine shop, maybe made special the hollowed nut is a bit odd but part of the assembly goes over the flats covers the set screw and tightens up against the smooth round base portion. Makes it really easy to hold too.

Got me

 

[RTM]

Could it be for panel conduit knockouts?

 

[B_Nabs]

Yep it's for cheapo hole saws that have a hole in them with flats on the sides instead of threads.

Sent from my SM-G975W using Tapatalk

 

[joe_padavano]

 

[darkzero]

I think it's just a hole saw arbor too. With inexpensive ones there is no standard for the hole saw size. I doubt it's shop made cause it's not likely it would have been black oxide coated.

 

[DFB]

Well you know what I think I have some of them super cheapy hole saws somewhere from long ago I'll have to check. And now that I see the photo with cups the arbor its looks like a given...thanks

You guys are right on top of it

 

[Machineman84]

Anybody have any idea what the original purpose of this bit holder may have been? Its something I had in with my metal working drawer of drill bits, files, reaming and tap tools.



Where it came from I don't recall. Maybe came out of the old electronics manufacturing plant way back when and was used on some assembly job there



The threaded mandrel is very similar to one for like a hole saw with the set screw to hold the bit, but it's not the right size. At least not for the saws I have. The hex shank portion must have been for a chuck though I would say



Wondering is it something out of the old machine shop, maybe made special the hollowed nut is a bit odd but part of the assembly goes over the flats covers the set screw and tightens up against the smooth round base portion. Makes it really easy to hold too.



Got me

This is a the hole saw arbor for your shown hole saws it may seem to not work becuse there is a piece missing from your photos. It’s. A flat rectangular piece with a small pin on either side. And a it has an odd shape hole in the middle to fit on the arbor and the two pins drive the hole saw.


Sent from my iPhone using The Garage Journal mobile app

 

[DFB]

Ya that's all it was

But where it come from I still don't remember (maybe a set long discarded)

One thing of notice on these cheapie sets is the tolerances of the cutout in the cups

That mandrel being from some other set was just a tiny bit larger in size and only fit thru the hole of one cup. It is that close that a couple strokes with file on the steel cup should easily do the job if I ever wanted to use those again.

 

[darkzero]

This is a the hole saw arbor for your shown hole saws it may seem to not work becuse there is a piece missing from your photos. It’s. A flat rectangular piece with a small pin on either side. And a it has an odd shape hole in the middle to fit on the arbor and the two pins drive the hole saw.


Sent from my iPhone using The Garage Journal mobile app

Not necessarily. Smaller size hole saws don't have the 2 pins cause there's no need for them (high torque) & there's no room for them on the hole saws.

 

[DFB]

This is a the hole saw arbor for your shown hole saws it may seem to not work becuse there is a piece missing from your photos. It’s. A flat rectangular piece with a small pin on either side. And a it has an odd shape hole in the middle to fit on the arbor and the two pins drive the hole saw.


Sent from my iPhone using The Garage Journal mobile app

Thanks for pointing that out I do have all the parts including the flat locking plate with the pins