[Chriseg1]

OK, so I have a part that needs a 1mm dia through hole 3/8-1/2" deep. Any thoughts on the best way and/or tooling to do this efficiently. 2 holes per part, and several thousand parts total, but spread out over time in different runs. This is a scientific sensor, so accuracy counts. The prototypes have been 6061 Au, and deep hole peck drilling has worked well. But production parts will likely be stainless 303 or 304.

Thanks all

[txcncman]

"accuracy counts" - What does that mean? + / - 0.005 on location? +0.003 / - 0.001 on size?

[Chriseg1]

+/- 0.0005 location,

-0.0000, +0.001 size.

If best way is EDM or other, then that's what I will suggest to them.

[KenFoulks]

How big is the material?

[Chriseg1]

part Dia 0.3650", hight 0.5", hole spacing 0.104"

And depth will be 1/4"" to 3/8", not 1/2".

[Delw]

Personally I would use a drill bushing (drill guide) and do it in a hand mill, I did thousands of wire holes in hex(303ss and 304ss) in a hand mill and its far better than a cnc as you can feel it before it breaks wiping out a $50-$100 drill bushing.

With out a bushing/guide I wouldnt trust it in a cnc for that kinda accuracy.

cnc would work if you have a bushing/guide

[Chriseg1]

Thanks, I think I am going to push for doing the parts with EDM. They are asking for 600 micron holes now.

[KenFoulks]

I would use a Haas OM-2A: CNC | Haas Automation, Inc. | OM-2A - SPECIFICATIONS |

Center drill, drill, ream 50 parts at a time in about 1 hour.

[Chriseg1]

Thanks Ken, that would be a nice setup. I think its one that they were looking at to try and bring the work in house. The big thing for them is not buying the equipment, but hiring a qualified person to program and operate it. He is just not sure if he has enough work to keep the person on full time, and he wont hire someone unless he can give them fulltime.

[txcncman]

+/- 0.0005 location,

-0.0000, +0.001 size.

If best way is EDM or other, then that's what I will suggest to them.

Run!

Run like the wind!

Seriously, it is probably doable with all carbide tooling.

[ToyMaker94566]

Thanks, I think I am going to push for doing the parts with EDM. They are asking for 600 micron holes now.

I drill 50 micron holes by the thousands with a Haas DT-1, 600 microns is a walk in the park. :tired:

The hard part is actually setting the tool length.

[BigNizzy]

Do-able (sp?) with Carbide tooling Mitsubishi do a good range of long drills that work I am drilling holes 3mm deep 90 deep with excellent accuracy atm. The biggest problem with drills that big is you will really need high rev's.

MWS0060XB will get 20mm deep @16000 rpm with a 127mm feed

[Delw]

Maybe I mssunderstood, I was thinking these were cross holes? are they on the face f the part or are they acually crossholes?
cross holes fixture, but no crossholes and through the face then you will be fine with anything, with that type of finish I would definatly ream with carbide after drilling

[Chriseg1]

I drill 50 micron holes by the thousands with a Haas DT-1, 600 microns is a walk in the park. :tired:

The hard part is actually setting the tool length.

What tooling do you use? And , what have you come up with to set the length?

Most of our work is more artistic/ decorative. These small high tolerance parts are a nice change, I'm really enjoying the chance to do some work that is more precise again.

Yes, these are in a recessed machined flat surface. The placement accuracy has not been an issue, I'm more worried about the bit drifting. This is for fiber optics, and the holes need to be dead on parallel.

[txcncman]

Even though a "design engineer" has specified the tolerances for these holes, in all likelyhood, they have been way over-engineered. I was just arguing with someone yesterday about the precision "required" when making bone screws. You really think the surgeon with a hand drill, drilling into someone's bone is going to make that accurate of a drilled hole?

[ToyMaker94566]

What tooling do you use? And , what have you come up with to set the length?

Most of our work is more artistic/ decorative. These small high tolerance parts are a nice change, I'm really enjoying the chance to do some work that is more precise again.

Yes, these are in a recessed machined flat surface. The placement accuracy has not been an issue, I'm more worried about the bit drifting. This is for fiber optics, and the holes need to be dead on parallel.

I use printed circuit board or "PCB Drills" and are sold by most distributors. I even saw an add on this forum for them yesterday as I was responding.

As far as setting a drill that is thinner than a hair, I use a 50X digital microscope camera I got on ebay for $50, even came with a 4" LCD monitor. Before that I pretty much went cross-eyed setting them - broke a few before they ever got ran.

BTW, I also run those tiny holds in my VF3 when the DT-1 is backlogged. It's all about technic.