[rrrun]

When Vectric released the Spring Wreath as a free project, I showed the picture to family.

I was told to make 2 of them. Well, OK, then.

There are 3 tool paths. The rough cut is with a 1/4" end mill, and my Aspire software said that cut would take 1:06. No problem. The finish cut is done with an 1/8" ball nose, and that cut was projected at 3 hours 56 minutes. I pushed the button at 2pm yesterday.

I finished cutting the first one this morning, and that's the problem. The cut finished at 7:15a this morning ... 17+ hours later.

The best news is that the raw project looks very good. But, I have no idea why the projected run time was SO FAR OFF. Any perspective to help me with that?

On a positive note, 4dThinker was wondering about air-cooled spindles, and mine did this cut like a champ. 17 hours, no breaks, no worries.

 

[UglySign]

No help here Henry but the machine ran all night long? Dust collection also?
I'd be shot & fed to the cats if that happened. Actually i'd be worried about the DC.

Nice project there, is that Poplar or Maple? Wild when it's partially thru how it looks
until the end result sets in.

 

[honesttjohn]

Don't believe Vectric's finish cut times. Did you have it on standard, high (3 times), or very high (7 times) setting??

Those times are figured on the ipm cutting constant. Doesn't take in the ups and downs and shape cutting where the spindle travels extra inches and slows down. I figure the finish cut is about 3 times what the program says. Also have to take in consideration of the amount of stepover rate. Set that thing up to 180-200 ipm and the spindle at 18000 rpms +/-. I got mine at 19000 for wood. That spindle is made to work 24/7. Use it when you have to.

I've burnt up one Ridgid vac in about 18 months. HD replaced it. I've also started a long finish cut and went to bed. Don't like to do that but when there's a deadline........ Always stick around the rough cuts.

Once you know what your machine will and won't do and get comfortable with it you'll be able to trust it and do other things while it runs.

Another hint (from 4D) -- you can usually use a 3/16 ball nose instead of a 1/8 for most things.

 

[Semipro]

Henry
Just a curious question did you stay up all night or go bed and let it run?

 

[4DThinker]

Yep, you can't trust vectric's software toolpath cut time estimates. For simple 2D cuts maybe, but not for 3D cuts.

You can sometimes reduce the total time it will take by setting the plunge rate of the bit you'll be using to the fastest value your machine will allow. It usually doesn't hurt to speed up the feed speed for the bit either. Generally because of all the direction changes in a 3D cut the speed is self limited.

4D

 

[rrrun]

No help here Henry but the machine ran all night long? Dust collection also?
I'd be shot & fed to the cats if that happened. Actually i'd be worried about the DC.

Nice project there, is that Poplar or Maple? Wild when it's partially thru how it looks
until the end result sets in.

So surprised the software has no better accuracy for predicting cut lengths. For what I paid for Aspire....

The machine ran all night long.

I typically run the DC for rough cuts, and then it's on & off for the finish cuts. I have found the dust collar on the spindle contains much of the dust during operation, especially on finish cuts. So, for this project, I ran the DC for the rough cut for an hour ... and it was midday. No problem.

For the finish cut that ended up running over night, I only ran the DC when I checked on the machine.

I ended up napping all night; never went to bed. I checked on the machine in the garage every 45 minutes or so. I can hear it from the living room when I mute the TV, so I monitored it remotely regularly ... but didn't actually watch the machine for 17 hours. Yes, I'm thinking about getting a video camera for the shop, but have not done so yet.

I do know that when I cut the 2nd Spring Wreath, I won't be pushing the button to start the finish cut at 2 in the afternoon.

 

[rrrun]

Don't believe Vectric's finish cut times. Did you have it on standard, high (3 times), or very high (7 times) setting??

I was running the project on its original settings, and didn't even know about this option. I just found it: this project ran at a modeling resolution of extremely high, which is 20x slower.

The result is very pretty, but this is clearly not a commercial project!

 

[4DThinker]

The reason Aspire can't calculate a 3D cut duration is because of all the different machines it supports. Professional machines have a quicker acceleration factor than hobby machines. Among hobby machines a cut time can vary wildly. Between my CNC Shark and my Probotix Meteor the same file and bit settings can take two completely different times to cut. Even more spooky is that sometimes the Shark is faster, and sometimes the Meteor is faster.

4D

 

[Scottart]

Can't imagine a 17 hour cut with an 1/8 bit for that size of project.

check a couple things.

1. step over in the tool setting. it should be around 10 %. that means it takes 10 passes to cut 1/8". You can estimate cut time on rectangular projects after the first inch or so of cutting. one inch would take 80 passes, if it takes 20 minutes to finish an inch, you can get a good idea pretty quickly how long it will take to wrap up a project. a 1/4 bit will cut your time in half with the same settings...
2. tool speed. on both my CRP and my Shark you can turn the speed down from the controller if needed. but if the design came with a 25 ipm cut speed, this could take a long time
3. Raster cut. Raster cuts are several times faster.

I get the disappointment with the estimated time. As I recall Vectric has a place to adjust your timing in the system by loading actual times of a few projects. that way they account for your machine. I will dig through the training videos, but it is discussed somewhere in all that stuff.