Depth of cut

[River Lodge Carl]

I am new to CNC routing and am concerned about taking too deep a cut the first pass i.e., a final 1/2 inch depth on text in a sign. How many passes using a 60 degree v bit and how do I get them? I am trying to find that answers in the Vcarve pro tutorials. How do I sent up the tool path to get subsequent cuts that will get me to the 1/2 inch final depth without overstressing the bit?
thanks for the help. I am building a Pilot Pro 42x26.

[Rcnewcomb]

That is controlled by the Pass Depth when you setup to tool in the tool database. The help manual has a write-up on page 205.


Pass Depth
The maximum depth of cut the tool can cut. The Pass Depth controls the number of z level passes that are calculated for a toolpath. For example, creating a pocket 1" (25.4 mm) deep using a tool that has a Pass Depth of 0.25" (6.35 mm) will result in the toolpath making 4 passes.


As far as what the correct setting should be, that is dependent on:
1. the capabilities of your machine (strength of motors, power of spindle)
2. the bit you are using
3. material you are cutting

[creek]

Having trouble with the tool path depth. It is going to deep. Can you tell me how to change that? Do i go to the edit tool and change the pass depth and make sure it only makes one pass rather than several. See it if making several in certain areas the other seem to be ok?
Thanks for your help in advance.
creek in Rocky Face, Ga.

[FixitMike]

If you are using a V bit with a VCarve toolpath, the bit will go down until the cut touches the vectors on both sides, unless you have set a flat depth in the toolpath. If you set a flat depth, any part of the toolpath that is too wide to be cut with a single pass will be cut with multiple passes of the V bit using the tool stepover setting. This will give you a rough flat surface. The alternative is to use a Flat Area Clearance Tool.

There is a lot of information available on the VCarve toolpath in the Help--Help Contents tab.

[joeporter]

Creek, if your "edit tool" depth is deeper that your "tool database" value, then that is what it will cut. Every time you select a certain tool from the database, you need to check it's value in the edit section also. Remember, you will run a preview of the toolpath and you will be able to see how many passes it is making and how deep each one is. As far as pass depth, I have always heard no deeper than the diameter of the tool per pass. I am a hobbyist and my time is not important. A professional will experiment with his tool and material and machine and feed speed and RPM and come to a pass depth that will make him money. The fewer the passes, the quicker the job is done. Sometime when you are sitting around and not doing anything, do a Google search for "Chip Load Calculations" and that will give you a little insight into feeds and speeds......joe

[martin54]

As Randall has already said your setting will be dependant on your own circumstances. As well as being able to set the depth of cut in the tool database or during the toolpathing procedure using the tool edit button there is also an option to edit the passes which means not only can you alter the number of passes but you can set the depth of cut for each of those passes. If I am using a "V" bit profile cutting to a set depth then I quite often use this function, I set the depth of cut for each pass at a different value, quite a high depth of cut at the start where the cutting edge is small & then reduce it for each pass as the length of the cutting edge increases.

If you are using the vcarve toolpath then you won't have this option & can only use the options already mentioned but as you say you are cutting to a depth of 0.5 inch you may well not be using the vcare toolpath

[Barry Anderson]

If you are using a V bit with a VCarve toolpath, the bit will go down until the cut touches the vectors on both sides, unless you have set a flat depth in the toolpath. If you set a flat depth, any part of the toolpath that is too wide to be cut with a single pass will be cut with multiple passes of the V bit using the tool stepover setting. This will give you a rough flat surface. The alternative is to use a Flat Area Clearance Tool.

There is a lot of information available on the VCarve toolpath in the Help--Help Contents tab.

This is a good piece of information. Thank you.

Barry