Hi all pretty simple question that I would love you to feedback on. I am interested to know what are the ranges that you all do, mine at the moment tend to be in the 30 mins zone, I know the following is very subjective depending on job type material f&s etc but just trying to see what is concidered to be an avarage /long job.
Well it is not a simple question. It depends on your project, size, complexity, the type of cut, material, bit changing, etc. Another very important thing is the CAM software you use, for example, CC is not producing the most efficient toolpaths at times and I feel, it can probably waste 30 to 50% of milling time with the router moving from side to side for no apparent reason. I just did a couple of engraving jobs today and the time was in the 60 to 90 min range.
30 minutes for a average size job seems about common for me. I’ve been using the default feeds and speeds for now. I’m sure I could drive the machine faster, but finishing in 15 minutes isn’t too big of a deal for me since it’s a hobby.
Also I tend to group the cuts even if there isn’t a tool change. That allows each job to last 10-15 minutes. I can then clean up a bit, maybe take a break before moving on.
For my terrain relief models, a 125mm by 136mm model of Mount LeConte I did yesterday took me about 7 minutes for roughing (0.25" ball nose), then just under 1.5 hours to get the highly-detailed finishing pass done (0.25mm radius tapered endmill). Laser-engraving the trails on the model is about 3 minutes, and lasering the trail map with labels and everything on the reverse is 7 minutes. (I could use a slightly larger radius taper or a slightly larger step size, or both, but I’m really liking the detail I get in the models.)
The large 205mm by 225mm model of LeConte I made for myself took something like three hours, plus or minus an hour. (I don’t recall off hand, but it was about in that range.)
Now, the custom cribbage board I made for Christmas for my parents took much longer to get the design from my head to G-code, but machine time was vastly less than the 3D terrain relief models. A one-hour basic 2D job would strike me as long, but a one-hour 3D terrain relief model would seem pretty fast.
What really makes a difference in my job run times is the plunges. Too many, too slow, or too far can drastically raise the time a job takes. Of course, too fast or too low and you can end up breaking things and maybe having to start from scratch, so there’s a limit, but it’s somewhere to look for getting a bit of time back on some types of jobs. (If you’re doing 10mm slow plunges just to get to the top of your stock, and you’ve verified your stock is flat to less than a millimeter, that’s a lot of air time.)
I try to stay under an hour, mostly because I have a hard time babysitting the machine for much longer than that. I however have run jobs up to 5-6 hours when needed. I break apart every tool path as it’s own gcode file even when no tool change is involved, which also gives me a way of stopping/starting along the way. Some CAM software will give time estimates for each tool path which is handy.
My record is over 9 hours. I do small scale, intricate inlay work with the Nomad. The tiny bits I use, some smaller than 0.2mm, need slooow feeds. The 9 hours was in cutting the profile of a Manzanita snag with about 80 branches. Some of the branches are only a bit larger than 0.2mm. The profile of a MOP rabbit took probably 2 hours. The concern with pearl, I’ve found, is plunging slooowly.
Most of my other work seems between 0.2 hours and 1 hour.
Interesting so it would appear that my tool paths are about right then middle of the road, thanks for all the feedback always nice to hear / see what others are doing
I have run for 12 hours straight before on art style pieces but typically 1-2 hours. Lately i have been doing aluminum testing and those files have been under 30 minutes.
For bits 0.254mm and less I run 9000 RPM’s at 30 mm in hardwood. In terms of chipload I suspect this is way more than enough but the limiting issue with micro-bits appears to be deflection.
I may, at some point, challenge this protocol but I’m still trying to complete my first project and, after a depressing string of breakage, this works for now. Nothing special about 9000, high RPM’s is better here but I backed off the max a bit to keep the spindle from smoking during such long runs.