Cutter Compensation vs Stock to Leave
HTML-код
- Опубликовано: 9 сен 2023
- Cutter compensation and stock to leave are both ways to dial in dimensions very precisely. Using cutter compensation is faster and easier, but a little harder to understand.
Support me on Patreon: / johnsl
Thanks for the help! We were confused by those descriptions in F360 as well.
What we have found (in terms of tool deflection) is that if you want the BEST results from top to bottom in the hole or boss, use a bore (or ramp) cycle so that the cutter engagement is always similar (and gives you low tool pressure) and always do a spring pass.
We have been able to dial in hole diameters within a few tenths of the correct diameters this way interpolating holes (and saving us from pulling out the boring head or buying reamers for a few holes at a decent fit)
Wear comp is basically the industry standard these days.
Back in the Old Times, hand programmers loved using full cutter diameter compensation because they could program directly off of the print, and change end mill sizes on the fly. With CAM systems today, we don't need to do that (just change the tool in CAM and everything updates).
What we do need to do is compensate a little for the fact that end mill tolerances are not +/- 0, or comp out for tool deflection, or cutter wear. As such, we tend to leave the Diameter at zero on the tool page, but still output cutter comp moves and very small adjustments in the Wear column.
Be *very* careful playing with this though - if you set Compensation to In Control, the CAM system will output tool path directly on the wall you intend to machine, expecting the control to move it the .125" off the wall (with the aforementioned .25" end mill). If you forget this, it is pretty easy to have a nice little tool crash and kiss $40 goodbye.
This is a valuable explanation! This is one of those things that is a pain to figure out but then once you know it you know it.
The CDC settings tend to default with diameter mostly because the feature is going to be measured symmetrically on either side (as with a boss or bore, square pocket, etc) so the controller does the math for us knowing we want our caliper/micrometer measurements to directly increase/decrease. The vast majority of CDC measurements involve a direct change like that. A radius change would be useful when only cutting one side of the feature (maybe there's a datum on the opposite wall), or doing some kind of feature-to-feature distance measurement. Some machines change the terminology to CRC instead of CDC when you do that change lol
Now I get it as well! Thanks.
I was looking for an idea how to create mold which is not costing thousands of dollars for my product idea, your videos gave me hope that it is possible to create something cheaper, you make it look so easy, can i create a mold with just metal and cnc router?
My experience has been that trying to use cutter compensation for cutter diameter leads to issues. G41 and G42 adjust the path to the left or the right, but this can easily lead to ambiguities. I think it's fine if you use those G codes for minute adjustments for cutter wear, but I've found that trying to use them for the entire cutter diameter can lead to wild movements when entering and leaving compensation mode.
Maybe the Haas is smarter than Mach 3, but eh.
i've had the same problem with DATRON. Decided to use stock to leave and compensation in computer rather than cutter comp.
Hey, John, I was wondering on your AB injection molders. They have those pneumatic->hydraulic clamping cylinders. What are those things actually called? That name space of pneumatic/hydraulic booster/clamp/pressure multiplier/what-have-you is very crowded, so I've had trouble finding out more about them. Do they have branding/specs on them? What are your thoughts on those vs screw clamp/big toggle style clamps on injection molders? Thank you for producing all the injection molding content!
Here is the information on the one I have: www.jergensinc.com/en/product/intensifier-cylinders?c=35504
@@JohnSL Intensifier cylinders! I guess that's the term I was looking for. Is yours the 8:1 ratio or the 30:1 ratio version? Thank you so much for the info! Now that I know what those things are called, I'll be able to find out more about them/look for used ones, etc. Thank you!
John Wouldn’t you benefit to use the probe macros to check the dimensions inside the machine before removing the part
Personally I use in control and set half my tool diameter and then walk the wear radius in to achieve dimension which is a minus figure
Yes, I could. In this case, I'm using the wear compensation to try out different opening sizes with the Hytrel watch gasket and crystal to see if I'm getting the right water resistance. In other words, I don't know the correct size yet.
Nice video as always! Out of curiosity, If someone wanted to talk with you about injection molding, would that be possible? And if so, how could one do that??
have you ever tried to injection mold a super clear plastic?
Since you have a probe, Haas has a macro that will cut then probe and adjust cutter comp automatically
Ah, but that would require I have a target size. I'm using the manual wear compensation to try out different opening sizes with the Hytrel watch gaskets to determine which size provides the water resistance needed. Once I do that trial and error to get the target size, then I can use the macros to compensate automatically.
I’m dumber then a stump on this, but, wonder if there is a tool deflection parameter, that would also be relevant?
Deflection can definitely be a factor. I usually use GWizard to get an idea of what the deflection will be and adjust my feeds and speeds to minimize it for the end mill I'm using.