Z Zero from Spoilboard for Profile Cut Question

[Walt_S]

Trying to learn something new. I've always zeroed from the top of the material for everything. I now want to zero from the spoilboard for my profile cuts. So I put the zero plate on the spoliboard and zero as normal. Now I need to tell the machine how thick the material is, right? So I need to change the number in the Zero space to a negative number coninciding with the thickness of the material, correct? How do I go about this? I've played with the Zero tab but can't seem to find it there. Any help, maybe crayons and construction paper, would be appreciated. Thanks!

[steve_g]

Walt...
you need to re-toolpath with your material setup for z-zeroing from bed. If you need more info than that, and I'll elaborate when I'm home and not on my phone!
SG

[Walt_S]

Thanks, I'm confused. Was discussing it on the Vectric forum http://forum.vectric.com/viewtopic.php?f=2&t=27860&sid=797987429df2a6cea97f1c0d51219731 but now that I got out to the shop to try and figure it out it's not adding up. I figured how to change the spoilboard zero from 0 to a negative number in SB which basically puts 0 back to the top of the matrerial. I guess maybe that's it. If it helps for a thickness number I'm using -0.71 at the moment but it really doesn't matter in principle right now.

[Simops]

Not sure if I'm understanding this but the way I do it is in vectric (in my case Aspire) material setup section I select zero to spoilboard, set the material depth as per usual and that's it. Use the zero plate on the spoilboard to zero.
Cheers

[steve_g]

Walt…
It looks like the Vectric thread has hashed out the issues well…
Here’s another wrinkle… Because I’m old and forgetful, I have to do it the same way every time! I Z zero to the top of the material… BUT, if I’m cutting a perimeter that is going all the way through, I zero to the bed, raise the bit up the DESIGN thickness and re zero. This way leaving VCP set to zero to the top of material still works and I don’t have to remember to keep changing my setting in VCP.
SG

[Walt_S]

Walt…
It looks like the Vectric thread has hashed out the issues well…
Here’s another wrinkle… Because I’m old and forgetful, I have to do it the same way every time! I Z zero to the top of the material… BUT, if I’m cutting a perimeter that is going all the way through, I zero to the bed, raise the bit up the DESIGN thickness and re zero. This way leaving VCP set to zero to the top of material still works and I don’t have to remember to keep changing my setting in VCP.
SG

THIS is what I'm trying to accomplish. The Vectric thread has gone a thousand times over my head at this point.

I want to leave the settings in VCP at Z 0 to the top of the material. If I have to change it to the bottom each time for a profile cut I WILL forget.

I want to zero off the spoilboard...using the touch plate.

I want to then tell the SB control software how thick the piece is.

So after I zero, the machine raises up and stops.

Now, this is where I'm stuck.

Do I tell the machine to "go to" Z 0 (which will now be the top of the spoilboard), go to the "Zero" tab, select "Z Zero" and then enter into the "Zero" setting box the thickness of my material, as a negative number, for example -0.71? If I do this my Zero setting is now reading -0.71 with the bit at the spoilboard, and if I raise up to "0" the bit is at the top of the material. Sounds right in theory, but want to make sure before I ruin something.

[EricSchimel]

Walt, what Simops said is spot on....

You don't (and probably shouldn't) ever put a negative number in your material thickness in Aspire.

If you want to zero off of your spoilboard, do so with your zero plate and make sure that you have that set in Aspire in your material setup. If you want to zero off the top of your material do that with your zero plate as normal and make sure that it's set in Aspire.

30529

Screwing this up can result in two outcomes: You drive the bit into your table or work piece and ruin both your bit and your work, or at best you do a bit of air cutting. Trust me I've made the mistake several times of of not having Aspire match where I've zero'd.

So what you want is this: You never want to touch the setting in Aspire so you don't make that mistake, I get it. However, no matter how you slice it, you're going to remember to have to an extra thing. That "thing" is either remembering to have Aspire set to where you actually zeroed, or remembering to jog up your Z and zero there. I'd go with making sure that your zero plane matches what's in Aspire, it's more intuitive and it's the way things are "supposed to work".

I ALWAYS double check that where I've zero'd matches what I have in Aspire. It's part of my mental "pre flight check list" now. If you're that paranoid about forgetting, you could even ad an extra reminder into the starting script that makes you push the start button twice or something so that you remember.

[Gary Campbell]

Walt...
Due to the variations in responses in the Vectric thread, you may have been confused. Here is where:

"I want to leave the settings in VCP at Z 0 to the top of the material. If I have to change it to the bottom each time for a profile cut I WILL forget.

I want to zero off the spoilboard...using the touch plate."

You CAN NOT do this. Its simple.

If you wish to set the Z datum (z zero) to the spoilboard you must also set the Z datum to material bottom (spoilboard) in Vectric material setup. There are no other operations required, design exactly the same, no negative numbers, everything is the same. You don't need to tell the machine anything about the thickness, it doesn't care.

All that is required is that you enter, in your Vectric material setup, an accurate material thickness.

Don't try and make this complicated.

[Walt_S]

Thanks all!

Thanks Gary! That thread got waaayyyyyyyy over my head and way too many different options, and I didn't even want to get into different machine control software there as that just would have confused the issue even more.

As for all the other things over there, I'm doing very basic, simple, small, personal, one off signs. Nothing that requires 0.00000001 accuracy. I don't mind using the touch plate, for me it's easy and works for my purposes. My eyes don't. I'll never be to the level of needing much more in my lifetime.

Anyway, I will try using the zero to bottom in VCP. I always measure my material in several places with digital calipers so I have an accurate thickness to go from. I appreciate your simple and straightforward response after everything over there had my head spinning.

[Walt_S]

One more question. When I set the zero location in VCP to bottom and set the Cut Depth, say my piece is 0.71, can I put in 0.725 just to be sure? Will that, instead of cutting into the spoilboard like if I zeroed off the top, air cut just a fraction instead? Reason I ask is when I set materil thickness to 0.71 and cut depth to 0.725, even setting Zero to the bottom, it warns me that it will cut through the material.

[Gary Campbell]

Walt...
Yes you can, in fact you should. That warning will always occur on a proper outline cutout. It warns that you will cut thru, isn't that what you want to do?

[Walt_S]

Gary, lol, yes. Just wanted to make sure I was thinking the right direction (up not down). Thank you.

[jerry_stanek]

If you do this it will not air cut but cut into the spoil board that is why it is called a spoil board.

[Walt_S]

If you do this it will not air cut but cut into the spoil board that is why it is called a spoil board.

So then what is the purpose of zeroing off the spoilboard? I can cut into the spoilboard all I want zeroing off the top. Now I'm back to square one if that's the case. :/

[jerry_stanek]

If you zero off the spoil board and have surfaced your spoil board when you input the material and tell your software to cut the material thickness it should just cut your material. I always tell it to cut .001 more than the material and it just scratches the spoil board

[srwtlc]

Walt, you're over thinking it and wandering too close to the tall weeds. ;-)

It sounds like you do a lot of surface work, be it v-carving, pocketing, etc. in your projects. Just continue to z zero off the top of material at the machine and also in your job setup in VCP/Aspire. Always keep these two things the same. If you mix the two, you'll have issues, believe me! When it comes time to make a profile cut, just set your depth of cut to be at least the thickness of your material or just a small amount more so that you're sure to cut all the way through. No need to change anything at the control software. Now get out there and make some sawdust (of the proper size chip of course)! ;-)

The main purpose for zeroing off the table surface would be for those that do a lot of sheet goods or parts where you want to have a consistent thickness of material left over, such as a dado for cabinet parts that when assembled, will add up to the proper cabinet width. If you were to work this way and do some v-carving on the part, you would have to set the exact thickness of your material in VCP/Aspire, not nominal, otherwise your v-carving could be too shallow or deep. With zeroing on the material surface, your v-carving will turn out proper each time and you can just set a nominal job thickness and set your depth of cuts so that you at least cut through.

I work most of the time zeroing off the part and just set a nominal job thickness like 0.75", knowing that it may be a bit more or less and then just be sure my cut depth for a profile cut is deep enough to cut through.

[Keith Larrett]

If you typically zero to the top of the material, on those occasions where you create a file requiring you to zero to the spoil board, just create a note to remind yourself.

Edit > note > "Don't forget to zero to the spoil-board before running this file!!!!!!"

If you start the note with a period '.' it will automatically open when you open the file.

[knight_toolworks]

Walt…
It looks like the Vectric thread has hashed out the issues well…
Here’s another wrinkle… Because I’m old and forgetful, I have to do it the same way every time! I Z zero to the top of the material… BUT, if I’m cutting a perimeter that is going all the way through, I zero to the bed, raise the bit up the DESIGN thickness and re zero. This way leaving VCP set to zero to the top of material still works and I don’t have to remember to keep changing my setting in VCP.
SG
I have automated this. I have a adjustable screw connected to my z plate and i level it with the table. I made a little program where the machine jogs over to it zeros on it like normal waits for me to enter a thickness and then it refer's at that hight.
that way if something happens i can rezero without moving the material to get to the spoiloard.