Parabolic Drill Bit

[kooster]

Does anyone know a source for a .492 parabolic drill bit?
I received a PSI brad point and would prefer not to use it on acrylics.
As such, I'm searching around for one but the closest I can find is a 12.5 mm. I would like this bit for some Apollo Elite pens. Is the 12.5 mm the equavalent to the .492?

 

[reiddog1]

Yes. The 12.5mm is .4921 according to my drill chart. Hope this helps.

Dave

 

[jeweler53]

:glasses-nerdy:.492 inches = 12.4968 millimeters

I think 12.5 would be fine, although 3/1000 of an inch might throw you off. :glasses-nerdy:

I would bet your runout is significantly greater than that.

 

[kooster]

Thank you gentlemen.
Can you suggest a good reference chart I can access/print for
my personal use?

 

[Whaler]

Here is the best on I have found.
http://content.penturners.org/library/general_reference/hutdrills.pdf

Here is a link to the drill bits that I use.
http://www.arizonasilhouette.com/Drill_Bits.htm

 

[KenV]

Thank you gentlemen.
Can you suggest a good reference chart I can access/print for
my personal use?

There are several in the IAP Library. Different styles to present similar info.

 

[jjjaworski]

Try Metalworking Tools - Drills, End Mills, Taps, Machines, Measuring Tools, Abrasives, Power Tools and MRO Supplies | Travers Tool
They have lots of parabolic drills in several different types ( metal, coatings, lengths,etc.)

12.5M M35CO T&O PAR JL DRILL :: Uncoated M35 Cobalt Parabolic Jobbers Length Twist Drills | Travers Tool

That size looks a little pricey though.

You might try MSC as well.

 

[kooster]

Thanks again for all the great leads & references.