Accuracy of 5-axis mills

[sonlab]

What is the best that one can get in terms of milling accuracy of the lower end wet/dry 5-axis mills? Do any of them give you close to .001mm accuracy?

 

[zero_zero]

What is the best that one can get in terms of milling accuracy of the lower end wet/dry 5-axis mills? Do any of them give you close to .001mm accuracy?

Lower end ? Forget it...you'd need a very solid frame, glass scales, industrial tool holder, big $$$...etc... You'd be looking at +/- 20 microns at best...

 

[CoolHandLuke]

1um maybe not, but <10 um is most machines in the 50-100k range.

smaller will mean getting much bigger with your machine and more liberal with your spending.

 

[3D BioCAD]

What is the best that one can get in terms of milling accuracy of the lower end wet/dry 5-axis mills? Do any of them give you close to .001mm accuracy?

You would have to get Roeders if your biggest concern is accuracy. 1um......

Charles
3D BioCAD

 

[sonlab]

1um maybe not, but <10 um is most machines in the 50-100k range.

smaller will mean getting much bigger with your machine and more liberal with your spending.

Which machines claim < than 10 um?

 

[CoolHandLuke]

datron, versamill/3dbiocad, origin, and a few others i am too lazy to lookup.

 

[CoolHandLuke]

sub-10 mics is like par for the course. everyone can or should be able to do it. just doing it to metal AND other materials thats the key part.

also most coritec machines are around 10 mics accuracy iirc.

 

[Glenn Kennedy]

Machine accuracy claims are difficult to pin down. Some companies provide unloaded accuracy which is the accuracy of the mechanism. Others will show accuracy of components. In reality, accuracy is dependent on many things including tools, materials and strategies. An accuracy number that is derived under perfect conditions will not reflect the accuracy an end user will experience.

Rather than look at spec sheets it is better to get a few samples cut on the machines you are considering and then look at the fit and finish of the restorations you receive. Lots of numbers are thrown around but the fit and finish of the restorations coming off the machine and the ability for you to duplicate those results is the only thing that matters.

 

[BobCDT]

1 um for dental is not needed. For starters, a high quality analog dental impressions likely has 100 um of error. Most are much worse. Desk top scanner another +-10-20 um. Honestly, I don't believe one would see any significant clinical difference between a mill with accuracy of 1 or 10 um unless you are milling implant interfaces or titanium bars.
I agree with Glenn. Look at the parts under a microscope and determine marginal integrity. If it looks good your in the ballpark. Today, i believe there are a lot of dental specific mills that will meet the needs of most labs, dentists and patients. More important, buy a mill you can afford that has an ROI that works, from a company that will provide the needed support.

 

[ceram1]

1 um for dental is not needed. For starters, a high quality analog dental impressions likely has 100 um of error. Most are much worse. Desk top scanner another +-10-20 um. Honestly, I don't believe one would see any significant clinical difference between a mill with accuracy of 1 or 10 um unless you are milling implant interfaces or titanium bars.
I agree with Glenn. Look at the parts under a microscope and determine marginal integrity. If it looks good your in the ballpark. Today, i believe there are a lot of dental specific mills that will meet the needs of most labs, dentists and patients. More important, buy a mill you can afford that has an ROI that works, from a company that will provide the needed support.

We out source to a couple of different companies as well as mill in house, this exposes us to several machines that we know of. I can not truly evaluate the machines as the cam is not consistent but will say the big mill fits are impeccable and the little mills are good but certainly not as consistent.

 

[KentPWalton]

Milling dry Zr is different than milling metal. You can get away with slight inaccuracies when milling Zr, but can't get

away with those when milling metal. You have a shrinkage factor that can help those inaccuracies out. Metal is a 1 to

1 ratio and it much harder to get right. Dedicate a metal machine for metal and Zr for Zr. No switching back and forth.

 

[sonlab]

1 um for dental is not needed. For starters, a high quality analog dental impressions likely has 100 um of error. Most are much worse. Desk top scanner another +-10-20 um. Honestly, I don't believe one would see any significant clinical difference between a mill with accuracy of 1 or 10 um unless you are milling implant interfaces or titanium bars.
I agree with Glenn. Look at the parts under a microscope and determine marginal integrity. If it looks good your in the ballpark. Today, i believe there are a lot of dental specific mills that will meet the needs of most labs, dentists and patients. More important, buy a mill you can afford that has an ROI that works, from a company that will provide the needed support.

I disagree with the 1/10 of a millimeter accuracy of analog dental impressions, I think the stated accuracy of a good polyvynil is 99.8 + which I think comes out to be around 20 um difference. There are studies that show even better accuracy. I am assuming a very good impression ( you can take a very poor digital impression also) I would hope that a bar attachment fits better than 100+um??

 

[BobCDT]

I disagree with the 1/10 of a millimeter accuracy of analog dental impressions, I think the stated accuracy of a good polyvynil is 99.8 + which I think comes out to be around 20 um difference. There are studies that show even better accuracy. I am assuming a very good impression ( you can take a very poor digital impression also) I would hope that a bar attachment fits better than 100+um??

Most of the studies done on impression materials are bench top, not real world. I do agree that the actual materials are more accurate than the numbers I had written. The number i had posted are real world accuracy (also foff teh cuff with no studies to back it up) of everyday dental impressions.
Sorry for the confusion.