Speeding up 3D (Wine Cellar Door)

[Uncle Henry]

I went to set up the sample Wine Cellar Door to modify for my own use and gain some practice. I was shocked that the roughing pass alone would take almost 45 hours!. The finishing pass would take over 7 hours. I have not converted the files to G code but I suspect that there will be little difference.
I am using a 0.250" ball nose for roughing and 0.125" ball nose for the finishing pass. Both are set with a 10% step over and 80 inches per minute.
Any suggestions that would allow me to complete each pass in a 8hr +/- time frame or less?

[WhittlinShed]

I usually run mine at 3-3.5" per minute.... roughly 180" per hour.... Don't know what machine you are using, or what it's capable of, but this is the speed I use on my shopbot standard....

[COWBOY1296]

i typically use a 50 % stepover for my roughing and about 6 or 7 % for the finish. is your file too big or copywrited to keep you from posting it on here

[Rcnewcomb]

I run 3ips (180 IPM) on X, Y, and Z. Note the for 3D work the speed of your Z typically determines your overall speed.

[Adrian]

The speed estimates are meaningless until you've set the scale factor for your machine and have the correct feed rates and rapid moves set.

The scale factor will need to be adjusted from job to job as well as a 2D job has less compound moves (all three axis) than a 3D job. Not to mention that a 2D job with smaller parts will cut slower than one with large parts as the machine can't reach full speed before hitting a corner.

The suggestions about stepovers are 100% right (as has been said feed rates are completely dependent on what your machine is capable of) just don't expect the initial times from the estimate to be anything like the time the actual job will take. The estimator is great for seeing the effect different strategies will have on the toolpath time.

[zeeway]

Also keep in mind that you should use the largest tool your machine can handle for the roughing pass. I use a half inch end mill, typically at 40% stepover, but I keep my depth of cut to a conservative .125 inch. I usually set my feed rate to 200 ipm, as the actual feedrate is usually dramatically slowed down for 3d work. For the finish toolpath on large 3d work, I would use a .25 inch tapered ballnose bit...also at 200 ipm, but at 9% stepover. On the other hand, a large project will take considerable time any way you do it. And lastly, if there are parts of the job that can be done with 2d toolpaths, that will also help cut down the time required.



One of the great things about the Vectric software is that you can plug in different parameters and see the results in the total time. It may not be 100% accurate for your machine, but you can count on the relative differences, I have found.

Angie

[Uncle Henry]

Thanks all,
FYI I am using a Legacy Arty 36 and a Bosch router as a spindle. I usually manually set the speed just below the fastest for quarter inch or less bits
I reset the rough pass to use a 0.25" EM with a 0.125 pass depth, 50% stepover, 100 IPM feed rate. This reduced the time to a manageable 6 hrs +/- and the finish pass I used a 0.25" BN with a 10% stepover also 100 IPM the time calculated for this was about 6.5 hours.
I think using a 0.25 Ball Nose will produce satisfactory results on a project of this size. I'll see when I run it, which may be a bit in the future.
If anyone is interested, I just completed the Tuscan Clock project, using oak from Lowes. I used a lighter stain then sealed it and applied dark stain which I wiped off to leave some residue in the small crevices, then 3 coats of spray on poly. The calculated time was about 5 hours the actual time was a bit over 6 hours. A picture is attached