Are milling chucks obsolete?

[Vancbiker]

.......
The reason I don't like weldon only because they don't give an option to play with tool stickout.

Sure they do. You just grind the flat where you like, want, need, to change the stickout.

 

[JSL_MFG]

I love shrink fit holders but trying not to use them for roughing.
Heavy duty hydraulic holders or milling chuck (not weldon chuck) are best option for roughing.
The reason I don't like weldon only because they don't give an option to play with tool stickout.

I couldn't agree more. Shrink fits are fantastic for finishing operations.

I have one of those fancy Guhring hydraulic holders with the side lock pin for pullout resistance. Even their own endmills don't stick out correctly due to the flat distance from the flutes. I threw out the pin and use it as a normal hydraulic, works great even with heavy roughing.

 

[JSL_MFG]

Sure they do. You just grind the flat where you like, want, need, to change the stickout.

If it's a one-off, sure. But if you're running production that's not really feasible.

 

[OVodov]

Sure they do. You just grind the flat where you like, want, need, to change the stickout.

This one I know and using it sometimes. But how many flats you want to make if using the same tool in many jobs

 

[Vancbiker]

If it's a one-off, sure. But if you're running production that's not really feasible.

Why not? Using what ever tool management system you have, you just identify where the toolroom grinds the flat on the tool. Lots of places I've been to do that. Buy round shank tools and it's a simple operation on some old surface grinder.

 

[JSL_MFG]

Why not? Using what ever tool management system you have, you just identify where the toolroom grinds the flat on the tool. Lots of places I've been to do that. Buy round shank tools and it's a simple operation on some old surface grinder.

I've worked for a few global enterprise-level companies across different industries, and only one of those shops had a tool room. I wish they were more common, but I digest.

I run through 15-20 endmills per week due to heavy roughing. The long-term cost of grinding flats on my tools would quickly surpass the cost of a good hydraulic holder. It takes me 30 seconds to swap tools, and I don't have to worry about ensuring my tools are prepped by a grinder. I'm not saying you're wrong by any means, I started my career in that tool room grinding flats on specialty cutters. It's just an added step that could be avoided with the correct tool for the job.

 

[gkoenig]

An important consideration in this discussion is how we define "roughing".

My world is small-part BT30 production. If your world is large aero structures in HSK63 machines, or you do mold work in big CAT40 machines... we are all going to have very different definitions of "roughing."

 

[OVodov]

An important consideration in this discussion is how we define "roughing".

My world is small-part BT30 production. If your world is large aero structures in HSK63 machines, or you do mold work in big CAT40 machines... we are all going to have very different definitions of "roughing."

If we are already talking about dangerous of pulling out tool from holder so it’s going to be really rough operation.

 

[JSL_MFG]

An important consideration in this discussion is how we define "roughing".

My world is small-part BT30 production. If your world is large aero structures in HSK63 machines, or you do mold work in big CAT40 machines... we are all going to have very different definitions of "roughing."

Regardless of what "roughing" is to you, the main benefits of certain holder types stand. Depending on your tooling setup, you'll get different levels of holding force, rigidity, and vibration dampening. I think the bigger question is what material we're talking about. Any holder will react very differently depending on what material and cutting forces you're putting it through.

 

[crossthread82]

An important consideration in this discussion is how we define "roughing".

My world is small-part BT30 production. If your world is large aero structures in HSK63 machines, or you do mold work in big CAT40 machines... we are all going to have very different definitions of "roughing."

While different holders definitely do excel at certain things than others.

I think we're all missing that the OP said this is a BBT30 spindle, I don't think its capable of pulling a tool out of any holder type unless it's used/assembled incorrectly.

 

[JSL_MFG]

While different holders definitely do excel at certain things than others.

I think we're all missing that the OP said this is a BBT30 spindle, I don't think its capable of pulling a tool out of any holder type unless it's used/assembled incorrectly.

My robodrill says otherwise. You can easily hold a 1/2" diameter endmill in a BBT30 spindle. Let's pretend you're using a high helix 1/2" endmill in 6061 and roughing with a 10% radial stepover at 1.5XD. Would you hold that in an ER collet? I wouldn't...

 

[gkoenig]

Regardless of what "roughing" is to you, the main benefits of certain holder types stand. Depending on your tooling setup, you'll get different levels of holding force, rigidity, and vibration dampening. I think the bigger question is what material we're talking about. Any holder will react very differently depending on what material and cutting forces you're putting it through.

The other factor is tool length. Not for nothing, but in the CAT40 video, the worst performer is shrink fit... but it is also sticking out from the spindle an extra 1.5" compared to every other holder in the test.

The BT30 community started bucking the trend and going with side locks because the system is more sensitive to others when it comes to gauge length, and Frank @ MariTool cooked up holders with basically zero projection beyond the flange.

 

[JSL_MFG]

The other factor is tool length. Not for nothing, but in the CAT40 video, the worst performer is shrink fit... but it is also sticking out from the spindle an extra 1.5" compared to every other holder in the test.

The BT30 community started bucking the trend and going with side locks because the system is more sensitive to others when it comes to gauge length, and Frank @ MariTool cooked up holders with basically zero projection beyond the flange.

That's a great point. A big plus spindle seems to help a lot with BT30

 

[crossthread82]

My robodrill says otherwise. You can easily hold a 1/2" diameter endmill in a BBT30 spindle. Let's pretend you're using a high helix 1/2" endmill in 6061 and roughing with a 10% radial stepover at 1.5XD. Would you hold that in an ER collet? I wouldn't...

In an ER32 with a bearing nut torqued to 100lb-ft I wouldn't have any issue running that in an ER holder. Gauge length in this scenario is going to be more important than raw holding power.

 

[JSL_MFG]

In an ER32 with a bearing nut torqued to 100lb-ft I wouldn't have any issue running that in an ER holder. Gauge length in this scenario is going to be more important than raw holding power.

Gauge length won't change the pulling forces put on that endmill. It'll change the vibration and holder rigidity, but the OP was worried about the pullout. If you're running production with an ER32, your tool life will suffer, resulting in even higher pulling forces as the endmill dulls. There are a million ways to skin a cat, but ER collets will never be able to match the holding power of a hydraulic or milling chuck.

 

[mhajicek]

ER systems, and similar systems, I don't see too many pull outs if the collet is torqued properly. I'm comfortable running moderate cutting forces and speeds up to 15k unbalanced.

Just for reference, I run ER at 50,000 RPM. No balancing, just put it together and go.

 

[crossthread82]

Gauge length won't change the pulling forces put on that endmill. It'll change the vibration and holder rigidity, but the OP was worried about the pullout. If you're running production with an ER32, your tool life will suffer, resulting in even higher pulling forces as the endmill dulls. There are a million ways to skin a cat, but ER collets will never be able to match the holding power of a hydraulic or milling chuck.

I'm not going to argue the fact that there are better holder systems on the market, I know, I use Rego PG for pretty much everything except HSS drills. The op asked about pullout not runout, and he appaers to be budget minded as well. And in a 10kw BBT30 machine you really shouldn't be able to pull a tool out of any of the holder types listed unless there is operator error involved. Now runout is a different story, that the ER loses almost every time.

 

[JSL_MFG]

I'm not going to argue the fact that there are better holder systems on the market, I know, I use Rego PG for pretty much everything except HSS drills. The op asked about pullout not runout, and he appaers to be budget minded as well. And in a 10kw BBT30 machine you really shouldn't be able to pull a tool out of any of the holder types listed unless there is operator error involved. Now runout is a different story, that the ER loses almost every time.

My robodrill has a BT30 14kw spindle, and I have had pullout (not runout) issues with an ER32 twice. I run very aggressively in roughing applications, so I changed to a big daishowa hydraulic holder, and it never happened again. Trust me... it's possible.

It depends on the OP's application more than anything. I'd love to see exactly what he's doing to say if it's going to be something he would need to watch out for.

 

[TAIWA NUMBA WAAN]

I'm not going to argue the fact that there are better holder systems on the market, I know, I use Rego PG for pretty much everything except HSS drills. The op asked about pullout not runout, and he appaers to be budget minded as well. And in a 10kw BBT30 machine you really shouldn't be able to pull a tool out of any of the holder types listed unless there is operator error involved. Now runout is a different story, that the ER loses almost every time.

I care about all the metrics of tool holders, I know everyone on this forum has different opinions and some have arcane knowledge, I just like to read what everyone is saying, since the users here aren't salesmen lying to convince me to buy whatever new tool holder and endmill they say is best. It's nice to have the forum users here explain exactly why they use the tools they do, giving their reasons, experiences, anecdotes, etc.

As far as budgeting goes, I think I'm in a different world here in Taiwan, because there are like 100+ machine tool builders in my city and dozens of tool holder manufacturers here as well. So I can get locally made tool holders at about 25% of the cost as in the US or EU. The only type I can't seem to find locally is stubby hydraulics in BBT30.

I have mostly used CAT40 and BT40 VMCs when doing short run production before, in 2023 I will be running exclusively BBT30 but I'm convinced if I pick the right tools, I can max out the spindle power and MMR. I think pullout can be catastrophic, I don't want to trash a built-in-motor spindle just because I picked a bad tool holder for a certain cut. So that's why I think the gripping power and pullout prevention is top priority, with runout, rigidity, gauge length, and price being the other main factors. And from what the Speedio/Robodrill people here say, I think gauge length is 2nd priority after pullout resistance. But then I also have the high speed requirement, which complicates it.

In my application, the requirements/priorities are;
1) No pullout
2) Balanced at high RPM
3) Preferably short
4) Low runout
5) Price

 

[crossthread82]

I care about all the metrics of tool holders, I know everyone on this forum has different opinions and some have arcane knowledge, I just like to read what everyone is saying, since the users here aren't salesmen lying to convince me to buy whatever new tool holder and endmill they say is best. It's nice to have the forum users here explain exactly why they use the tools they do, giving their reasons, experiences, anecdotes, etc.

Ultimately that's what all of our opinions are boiling down to; different holders do better in different applications.

...The only type I can't seem to find locally is stubby hydraulics in BBT30.

I had Schunk quote me for some custom made stubby BBT30 1/2" bore hydro's that were about 35mm gauge length. They would basically be one of their 50mm gauge length bt30 tendo platinum holder with the length adjustment screw section removed to shorten the holder and also be be ground to BBT30 instead of BT30. They wanted $1000usd a piece with a minimum order of 10.

...And from what the Speedio/Robodrill people here say, I think gauge length is 2nd priority after pullout resistance...

From what I remember you're using this in a new yet to be released BBT30 horizontal, correct? If so that's a different animal compared to a speedio. Robo's and Speedio's have kind of wimpy drawbars in them which is what makes the gauge length requirement so critical. If you know what the drawbar force on your machine is let us know, since that'll determine how much stick out you can get away with. If it has 800-1000+ lbs of drawbar in it it'll handle longer tools a lot better compared to most vertical BT30 machines.

In my application, the requirements/priorities are;
1) No pullout
2) Balanced at high RPM
3) Preferably short
4) Low runout
5) Price

The only one that really checks all the boxes is heatshrink. Downside being you need the shrinking machine. And you need a different holder for every tool you have.

The PG holders from rego that I use get you 1,2,and 4 but not so much 3, and definitely not 5 lol.

Weldon holders get you 1,3, and 5. But not 2 or 4. And like the heatshrink you need a different holder for every sized tool.

This is really going to come down to which one you want to compromise on.