Router programming

[Stephen]

Hello,

 

Does anyone know how industry programs CNC routers? I have a new Onsrud machine and they program with positive numbers from the spoil board. Basically part zero is the bottom of the part. I'm beyond confused coming from a machinist background with Z zero being the top of part in most cases. I don't understand how to approach cut depths and tool clearances.

 

Is Mastercam Router setup for this or do I need to make changes in the program to cut this way?

 

Thanks!

[Guest MTB Technical Services]

Hello,

 

Does anyone know how industry programs CNC routers? I have a new Onsrud machine and they program with positive numbers from the spoil board. Basically part zero is the bottom of the part. I'm beyond confused coming from a machinist background with Z zero being the top of part in most cases. I don't understand how to approach cut depths and tool clearances.

 

Is Mastercam Router setup for this or do I need to make changes in the program to cut this way?

 

Thanks!

 

What you think is a problem is not a problem.

Where you place the part zero is up to you as the programmer.

Mastercam will only do what you tell it to.

 

Use the Incremental option in each operation for depths and clearances.

This is not the same as G91 mode.

This merely means that the values used will be relative to the current location of the selected geometry.

[Thee Awbade™]

Most of the time in Router machining, the top of the part is not a reliable variable. So we use the table. At least in my experience it has been that way. or the top of the part is not flat or any sort of a check surface. Bottom of Part (Or Top of Table.) is a checkable reliable reference, which is why we use it. 

 

Now for depths etc, you can set all of that using incremental from your toolpath geometry if it's giving you a problem, or do absolute and calculate from your reference point. It should make 0 difference which you use in programming as long as you stay consistent and do your set-up properly.

[thereclinerman]

depends on the parts u are cutting as to the way u approach it. by using your setup,  you cannot cut into the table unless you use a negative in front of your number to go below z zero. any positive numbers will alway get u further from the top of the table. we are cutting plywood parts for furniture and all of our cuts are through two sheets of osb/playwood. because of small differences in  thickness of the material, i set my cut depth at  -1.5708 and then when i post it, i raise the z height to 1.5 with the clearances and approach  set at 1" .  have thermwood routers, using mastercam x5 router level 1

 

u can email me at jim dot huskey@yahoo dot com if u like.

[Jayson Kramer]

I have a customer I have been programming for over 3 years with now a few Thermwood, we doing Boeing work. everything comes from the spoiler up. this way as stated you do not cutting to the spoiler and break vacuum. All your values are positive. you will get used to it fast. Now if you are using the 5axis you can still have some Negtive numbers at lower tilts. the ones I program are 5 axis and 3 axis.

[Stephen]

Thanks for the info! It does take some getting use and has pros and cons compared to programming from the top of part. We just made our first parts and all went well.