Wow, very good discussion going on here. When I wrote the ramp entries, I gave it quite a little thought.. Currently the feed rate is set very simply: if any segment of the path has different starting Z and finish Z, the vertical feed rate will be applied. Not very clever, so I am happy to implement it in better way when some sort of conclusion is reached how it should be done.
I think my favorite is that the feed rate is set so that the speed of the Z movement is set to the desired vertical feed rate, so basically the resulting speed along the ramp is 1/sin(angle)*vertical_feed, right? Of course that must be limited if it exceeds the set horizontal feed rate. If I understood right, that is what chrisb said in the pdf with a bit different perspective?
herbk wrote: ↑Sun Nov 26, 2017 11:00 am
But this is one of the minor problems that "Ramp entry" has in that moment... For me a much bigger foult is the behavior, that the path after each round goes back to "Clearance hight" and starts every ramp at "safe hight".
Yes - this is something that is inherent to the the current algorithm. What it does is that it searches for any non-rapid paths which go straight down on Z axis and turns that into the ramp. And it seems that some (all?) Path operations generate a path where the full travel from clearance/safe height (I get confused with these) to the current operating depth is issued with G1. At the current implementation of the Path operation & dressup functionality, the dressup does not know pretty much anything from the PathOp, except for the actual generated Path. So for the dressup it is difficult/impossible to guess which of the Z moves are supposed to be not ramped - the only way to check is that if the move is rapid or not.. Something could be guessed from the stock object for example, but probability of guessing wrong is quite large. So the best way would be that the operations would be implemented so that the rapid would be stopped just before the tool touches the stock and not before. Good luck doing that in practice.
All ideas on making this better are very welcome.
herbk wrote:keep tool down makes no different, but i will see what the next update solves...
I think nothing has been done for ramp dressup for the last three months, so I'm afraid it solves nothing..
Pekka