Drilling holes...what tool?

[DMC]

For milling holes (drilling operations)...what tool shape is the best?

Radius corner end mill (Torus, Bull-nose, other names? all same shape)

or a Twist-drill tool?

Scott

 

[DMC]

If your answer was a radius corner end mill....then Two flute, or Four flute?

I'd amagine that 2-flute is better when tools are smaller than 2mm in diameter?






What about Roughing with larger radius-corner end mills? (2mm-4mm dia.)Again, Four flute or Two flute?

I would think that the Four Flute are more expensive and harder to manufacture. What is benefit of Four vs/Two?

 

[DMC]

Well, this is my strategy for now.....

1)PRE-DRILL with a radius corner....just to clean the top of hole and to start a pilot mark/hole just a wee-bit into the hole area.
2)DRILL with a long Twist-drill the majority of the material from the hole...top and bottom. Now we see daylight through the canal.

3)PRE-FINISH with now a radius corner again....just cleaning up and slightly widening the hole to proper dimentions.
4)FINISH DRILL with same style tool. Tight passes. Leaving smooth surface and cleaning up the seating area for screw...

Below is a snapshot of the first operation. The "PRE-DRILL"
It only just "tickles" the hole a little. Not FULL-PENETRATION. LOL
We do that next with different tool.

 

[DMC]

SUM3d has "Smart Drilling"

The tool goes down a bit, then pulls back to clean out chips, then back down again, then up, then back down further...etc.

Like a Pogo stick going deeper and deeper.

This is DRILL with a Twist-drill tool.....
This file is from exocad and sum3d automatically used the ConstructionInfo Text file of coordinates that is associated with the CAD stl file.
We need Two files to be more accurate, as previously mentioned on this site...One CAD and One is text.

 

[Drizzt]

Looking good ! Are they reall cases or samples ?

 

[DMC]

REAL samples! LOL

 

[Dejvis]

Hi Scott

For milling holes Twist-drill tool are Super

But i use a little different strategy for implant bridges and bars

 

[Drizzt]

Scott , these are the tools I told you I would post 2-3 days ago . 2mm and 1mm .

IMG_0903_zps74bed93e.jpg picture by drizzt85 - Photobucket

IMG_0904_zps5a46550f.jpg picture by drizzt85 - Photobucket

 

[DMC]

Hi Scott

For milling holes Twist-drill tool are Super

But i use a little different strategy for implant bridges and bars

So what's different? Because I actually started with the Daytron Template.
PRobably the same one you have in fron of you. Maybe some words are different?

Can I have your strategy to see? Ypu can have mine as well if ya want? But it is not tested very much yet.
I'm sending ya my email if you feel like sharing...

Scott

 

[greeny]

here's another interesting/useful tool for drilling holes:



it's used instead of the helical path ball mill in the pre-drill step (as you called it). it's a simple drilling operation that creates a small pilot hole - sorry but it's hard to see that the tip of the tool comes to a single point in the picture. it prevents the following step, the actual drill, from running on initial contact. both ways are completely acceptable, this is just another alternative. there are slight advantages and disadvantages for each.

 

[DMC]

Cool.

Thanks for the quick order on the tools Jordan!

We are trying them now.

Scott

 

[greeny]

No problem! I saw in your other thread that they're having the same problem your other tools had. This is OK though, you're eliminating the potential problems one at a time so you can zero in on the actual culprit.

Do you want to send me one of those crappy CrCo blanks to see if I'm having similar problems with tool life? Or are they going back to the manufacturer?

 

[Dentaleng]

I use corner radius for roughing and Flat for finishing. No Drills. I would love to use drills though, but for a lot of reasons I don't.

 

[Dentaleng]

The milling parameters especially the DOC or the fixture overhang seems to be the main culprits. I use CrCo from Eisenbacher and its quite hard.

 

[DMC]

No problem! I saw in your other thread that they're having the same problem your other tools had. This is OK though, you're eliminating the potential problems one at a time so you can zero in on the actual culprit.

Do you want to send me one of those crappy CrCo blanks to see if I'm having similar problems with tool life? Or are they going back to the manufacturer?

OK, you are welcome to have a "whack" at it!

You will have tommorow!

 

[DMC]

I use corner radius for roughing and Flat for finishing. No Drills. I would love to use drills though, but for a lot of reasons I don't.

You are prejudice against twist drills huh? It is the correct tool to make a hole I believe.

 

[Drizzt]

The milling parameters especially the DOC or the fixture overhang seems to be the main culprits. I use CrCo from Eisenbacher and its quite hard.

Are you happy with Eisenbacher CrCo ? Is it too hard ? What about bond with porcelain ?

 

[Dentaleng]

You are prejudice against twist drills huh? It is the correct tool to make a hole I believe.

If I have to use drills, the process becomes too long, Pre-drill, Drill and Flat for the bigger hole and similar for the smaller hole. Almost 5 tools to make a single Countered bored hole.

 

[Dentaleng]

Are you happy with Eisenbacher CrCo ? Is it too hard ? What about bond with porcelain ?

1 year and have seen no complaints yet. Mostly 10-16 unit bridges.

 

[DMC]

If I have to use drills, the process becomes too long, Pre-drill, Drill and Flat for the bigger hole and similar for the smaller hole. Almost 5 tools to make a single Countered bored hole.

Go get a mill that does sub 2 second tool changes. (POW-POW...back to milling) Then you won't worry about changing tools often during milling?