Author Topic: Can't (yet) find the drill I need.  (Read 1752 times)

Offline lloydsp

  • CNC Jedi
  • *****
  • Posts: 8297
    • View Profile
Can't (yet) find the drill I need.
« on: November 21, 2019, 20:57:17 pm »
I need a 0.5" x 118-degree standard 'twist drill' (for metal), short (2.5") would be nice though not absolutely necessary, AND with a 1/8" pilot point at least 0.040" long on its vertical sides.

All I've been able to find in pilot drills offer a FLAT full-diameter face, instead of the 118-degree tip.

Having one (and a source for more) would save me over 40 minutes - by eliminating a MOp - on a job I'll be doing repetitively over the next three years.

Thanks, all.

Lloyd
"Pyro for Fun and Profit for More Than Fifty Years"

Offline EddyCurrent

  • CNC Jedi
  • *****
  • Posts: 4390
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #1 on: November 21, 2019, 21:09:09 pm »
Made in England

Offline lloydsp

  • CNC Jedi
  • *****
  • Posts: 8297
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #2 on: November 21, 2019, 21:18:26 pm »
Well, Eddy,

Yes, "like" those, but with a 1/8" diameter pilot, rather than 'screw or tap' sizes.  What I'm doing is drilling a 1/2" hole, then penetrating the bottom with an 1/8" drill in order to open a path to features milled on the bottom of the board.

But the major hole must be 1/2" with 118-degree tip, and the pilot must be 1/8" in diameter.

Thanks,
Lloyd
"Pyro for Fun and Profit for More Than Fifty Years"

Offline kvom

  • CNC Jedi
  • *****
  • Posts: 1572
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #3 on: November 22, 2019, 00:30:02 am »
Take stub length 1/2" drill bit.  Mount in lathe and drill 1/8" through hole using carbide drill bit.  loctite desired length of 1/8" drill bit in the tip.   ???

Offline lloydsp

  • CNC Jedi
  • *****
  • Posts: 8297
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #4 on: November 22, 2019, 00:58:39 am »
Kvom,
Have YOU ever tried drilling a hole in the nose-end of a hardened 118-degree twist drill?  I mean, really.

I'd rather have one 'custom ground' than to try to modify a good-quality drill!

Lloyd
"Pyro for Fun and Profit for More Than Fifty Years"

Offline dave benson

  • CNC Jedi
  • *****
  • Posts: 1325
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #5 on: November 22, 2019, 01:56:25 am »
Lloyd
search for pilot bore countersink's
Dave

Online Bob La Londe

  • CNC Jedi
  • *****
  • Posts: 3952
  • ^ 8.5 pounds on my own hand poured bait.
    • View Profile
    • CNC Molds N Stuff
Re: Can't (yet) find the drill I need.
« Reply #6 on: November 22, 2019, 01:57:49 am »
Depending on what it is a shop ground D-bit might do the trick.  I have a few pieces of W2 laying around the shop for stuff like this.  
Getting started on CNC?  In or passing through my area?
If I have the time I'll be glad to show you a little in my shop. 

Some Stuff I Make with CamBam
http://www.CNCMOLDS.com

Offline Garyhlucas

  • CNC Jedi
  • *****
  • Posts: 1366
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #7 on: November 22, 2019, 02:08:44 am »
Lloyd,
The type of drill you want is called a subland drill. Look at 29475A81 at McMaster Carr. OD and angle are what you want but tip is oversize. You might be able to have one made as a special.  These are short too.
Gary H. Lucas

Have you read my blog?
 http://a-little-business.blogspot.com/

Offline lloydsp

  • CNC Jedi
  • *****
  • Posts: 8297
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #8 on: November 22, 2019, 02:13:22 am »
Yep, Gary.  I've already contacted a 'custom grinder' who will make such a bit for about $40 USD, onesies.

I'm betting they'd be closer to $30 USD each, if I bought five.  But FIRST, I'll test one on the job. <grin>

Lloyd
"Pyro for Fun and Profit for More Than Fifty Years"

Offline dave benson

  • CNC Jedi
  • *****
  • Posts: 1325
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #9 on: November 22, 2019, 02:24:28 am »
Lloyd this is what I was thinking of.
This is a cheap one, but you can get them with a hollow shaft and used with a panel drill allows you to set the
Depth of the pilot drill, the ones I've used for metal working come in 120 deg which may be close enough and they are quite inexpensive.
Dave

Offline lloydsp

  • CNC Jedi
  • *****
  • Posts: 8297
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #10 on: November 22, 2019, 11:44:54 am »
Thanks, Dave.

Lloyd
"Pyro for Fun and Profit for More Than Fifty Years"

Offline kvom

  • CNC Jedi
  • *****
  • Posts: 1572
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #11 on: November 22, 2019, 13:46:46 pm »
Kvom,
Have YOU ever tried drilling a hole in the nose-end of a hardened 118-degree twist drill?  I mean, really.

I'd rather have one 'custom ground' than to try to modify a good-quality drill!

Lloyd

I intended the drilling to start from the flat  end of the drill.  But since a custom grind is so cheap that's the way to go.

Online Bob La Londe

  • CNC Jedi
  • *****
  • Posts: 3952
  • ^ 8.5 pounds on my own hand poured bait.
    • View Profile
    • CNC Molds N Stuff
Re: Can't (yet) find the drill I need.
« Reply #12 on: November 22, 2019, 16:48:54 pm »
That's pretty reasonable for a custom ground drill.  Often for me its one of those things where I need to do it NOW which is why I sometimes make tools instead of waiting for them. 
Getting started on CNC?  In or passing through my area?
If I have the time I'll be glad to show you a little in my shop. 

Some Stuff I Make with CamBam
http://www.CNCMOLDS.com

Offline Garyhlucas

  • CNC Jedi
  • *****
  • Posts: 1366
    • View Profile
Re: Can't (yet) find the drill I need.
« Reply #13 on: November 22, 2019, 23:28:03 pm »
$40 sounds like a deal if you save 40 minutes each time. I had a carbide router bit made for producing 20 degree angled flanges that mate with Ag ball valves and sanitary flanges too. One tool does 3 different operations in one pass each and no tool changes. Huge time saver and improved part quality at the same time.
Gary H. Lucas

Have you read my blog?
 http://a-little-business.blogspot.com/