This is a short video showing the accuracy and repeatability for the Shapeoko HDM. These bores were made with a three flute 0.375" end mill with no predrill.
Curiously, the manufacturer of this machine has no mention of machine accuracy in the specifications on their website. That seems a bit odd when you consider what they're asking you to pay for it.
Given their general customer base being home hobbyists and makers, they would likely get a bunch of complaining because the users don't actually know how to create proper tool paths or maintain consistency when machining. Carbide's machines are fantastic for the price, and $5400 for a machine of this build quality is completely fair. I've been using their 4 XL for 2 years now and my only complaint is that it won't mill as fast as I want in Aluminum. That is my fault for pushing it way harder than the motors can handle.
How would this change, part to part, if your shop temperature changed by 40 degrees Fahrenheit? Does the combination of steel linear rails mounted on aluminum extrusions create warping or other accuracy problems?
When measuring millionths of an inch just the temperature of the human hand near the part or the probe will change the reading. Even if temperature was not a factor, the placement of the part or pin will affect the reading as will any repositioning of the height gage. The coefficient of thermal expansion for 6061 aluminum is 10-6 /K (μin./in. ·°F). For example, a dimension of 0.660" will increase by 0.00032472" if the temperature increases by 40 degrees Fahrenheit. Likewise, when the aluminum becomes heated enough to be warm to the touch while machining, then the final dimensions will be different than expected (which is why flood coolant is often used in production environments). Factor in machine positioning tolerances with thermal expansion, spindle run out, tool deflection, and tool wear and you can see why it becomes difficult to consistently produce parts to +/- 0.001" or better. Note: When I was just starting out in the manufacturing industry back in 1984 I initially worked as a machine operator. I learned the hard way that aluminum can get very hot at the cutting point during machining operations when coolant is not sufficient. A CNC programmer made an error (G0 vs. G1) and plunged a 1" diameter end mill into a part. This action literally melted the aluminum and ejected a small blob that landed on my neck. The cutting tool fused with the aluminum and couldn't be removed from the part. [FYI - The old Bridgeport Series I and Series II CNC 's were based on the standard milling machine design and lacked enclosures. Safety was an afterthought.]
Absolutely incredible for a machine of this price. What an exciting time to be alive!
well said
Nice for making this video on accuracy. What can you say about the accuracy for the shapeoko 5 pro?
Curiously, the manufacturer of this machine has no mention of machine accuracy in the specifications on their website. That seems a bit odd when you consider what they're asking you to pay for it.
Given their general customer base being home hobbyists and makers, they would likely get a bunch of complaining because the users don't actually know how to create proper tool paths or maintain consistency when machining. Carbide's machines are fantastic for the price, and $5400 for a machine of this build quality is completely fair. I've been using their 4 XL for 2 years now and my only complaint is that it won't mill as fast as I want in Aluminum. That is my fault for pushing it way harder than the motors can handle.
@@brynmrsh5400 is overpriced imo. Can definitely build your own at half the price and twice the rigidity.
Is it possible you’re trapping air at the bottom? “Air bearings” - so slick!
Assuming you didn't use carbide create to make the program, I would be interested to see a similar test using carbide create.
Fusion360, but you can machine aluminum with Carbide Create and Pro has the ability to ramp
😲 that's amazing!
I expected good numbers but not as good as that!
So the holes are very precise, but not very accurate.
within -.001 . Not accurate enough ?
@@joeygonzo they were supposed to be .438, they all turned out .434.
Precision and repeatability are much more important. The accuracy can be calibrated in. If the variance were large then it couldn't be.
@@Ivan_builds that's irrelevant, it can be calibrated with few clicks
Good job getting real metrology equipment out for verification.
How would this change, part to part, if your shop temperature changed by 40 degrees Fahrenheit? Does the combination of steel linear rails mounted on aluminum extrusions create warping or other accuracy problems?
When measuring millionths of an inch just the temperature of the human hand near the part or the probe will change the reading. Even if temperature was not a factor, the placement of the part or pin will affect the reading as will any repositioning of the height gage. The coefficient of thermal expansion for 6061 aluminum is 10-6 /K (μin./in. ·°F). For example, a dimension of 0.660" will increase by 0.00032472" if the temperature increases by 40 degrees Fahrenheit. Likewise, when the aluminum becomes heated enough to be warm to the touch while machining, then the final dimensions will be different than expected (which is why flood coolant is often used in production environments). Factor in machine positioning tolerances with thermal expansion, spindle run out, tool deflection, and tool wear and you can see why it becomes difficult to consistently produce parts to +/- 0.001" or better.
Note: When I was just starting out in the manufacturing industry back in 1984 I initially worked as a machine operator. I learned the hard way that aluminum can get very hot at the cutting point during machining operations when coolant is not sufficient. A CNC programmer made an error (G0 vs. G1) and plunged a 1" diameter end mill into a part. This action literally melted the aluminum and ejected a small blob that landed on my neck. The cutting tool fused with the aluminum and couldn't be removed from the part. [FYI - The old Bridgeport Series I and Series II CNC 's were based on the standard milling machine design and lacked enclosures. Safety was an afterthought.]
what that in metric?
..434 times 25.4