Inventables Community Forum

2 Stage Carve- 2 Problems

New CNCer here. I tried my first 2 stage carve (1/8 roughing bit and 60 V bit), and it looks like I made every rookie mistake. 2 major problems:

2nd Stage- Previous XY0 did not work.

  1. I accidently moved the carriage from the original XY0 location while changing the bit. I did not think this was an issue at first because I know there is a button for “return to previous XY0” location. It did not return to that “previous” location. Why not? Thankfully, I had a pencil mark at the center of the material, so I reestablished my XY0 there.

2nd Stage- 60 Degree V Bit cut too deep.

  1. My first stage went great. The 1/8 bit roughed in the design very well. I was cutting at an 1/8 deep. However, my 60 V bit cut too deep. It went below the depth of rough in on the letters of the sign and cut lines across some of the letters as it moved from the edges of said letters. I z-probed both times for both stages on the surface of the material. I saw on the Inventables forum that the cut depth for the 2nd cut needs to be changed manually before running the 2nd stage (60 degree V bit). Fair enough, but there is no guidance for HOW MUCH to decrease the cut depth. That is, if my roughing cut is cutting 1/8" deep, do I decrease the cut depth by half that amount? One quarter that amount?

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Thanks to anyone for your assistance and/or guidance.

Jason

When you changed your bit, you likely did not put the Vbit in the chuck at the same depth. Using previous xyz0, will start from the zero you did with the 1/8 bit.
In stead, when you choose the detail pass and the screen comes up to probe…re probe with your vbit now installed from a section of your stock piece that is still full height after the rough cut.

Then on the next screen choose use last xy location, and start the cut. It will remember your stock placement.

You can move the xy and z to change bits. The start location is saved. Even if you turn off the machine and detail cut the next day. Just re-home the machine. Choose detail cut, probe the stock, and use last xy location to start.

Thanks so much for the information! I can definitely see how a depth change on the Vbit could lead to issues on the second stage cut. I did a 2nd z-probe before the 2nd stage, but I also clicked on the button for the “previous XY0.” Maybe this is what took me back to the previous Z0 coordinate as well???

This confuses me a little because I did 2 separate z-probes, and the “previous” button seemed to only be for the XY0 (not the Z0). This must be the issue though. What you are saying is the only thing that makes sense.

I’ll try again. If you have any other advice, let me know.

Watch this video and do it to your XCarve

When you move the router by hand you lose the previous location.

This is a 2 stage carve that I did

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Thanks so much for all the info! I will watch all this stuff more carefully this evening, make the adjustments, and try again. Appreciate you taking the time!

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Hello again Russell,

I am still failing at this. I followed your advice on both counts.

  1. I watched the video about locking the motors. I flipped the 3 switches to off inside the and input the $1=255 in the inspector. When I click on “lock motors,” they don’t seem to lock.
  2. Regardless, I changed the bit without moving the carriage. I did the 2nd z-probe and chose “last XY0”. When it started to carve it carved the top left hand corner at the bottom left hand corner of the piece, as if it was using some XY0 from some other piece I cut ages ago.

Think I have to call tech support. The XY0 thing is really NOT working.

I dont know what happened there. If you hit last home position then it should return to that position.
When you turn on the XController you should hear the motors lock. When the XController is on you shouldn’t be able to move anything.regardless if you have it checked off in Easel or not.
Are you setting your home position to the bottom left corner?
Russell

Realize that:

  • Work zero is stored as an offset value relative to Machine Zero
  • When powering up the machine, it will assume this is at Machine Zero position
  • Performing a Homing sequence send the machine to the homing switches, which reset the Machine Zero position. You now have a fixed rerefence Machine Zero point
  • Since you now have a fixed reference point, Work Zero will be persistent aswell and “Use previous…” serve a purpose.

If the machine is not homed any stored offset value will result going to an arbitrary point.

Hi all, I am trying to understand the sequence of events when doing this project, Easel - Copy of Bass Lake Skier Key Rack

I tried to do the whole project with a 60º bit and in the beginning it was awesome until it went horribly wrong. I knew by common sense that this wouldn’t work but did it anyway. The v bit wound up jumping all around in the pine and wiping out the progress along the way. So, now I am wanting to try and do a 2 stage carve some down cut bit prob a 1/16th and a v bit for the detail. Question is, when I do the simulate the straight cuts end up being all v shaped and I am not sure it will cut it properly? Anyone have some advice to get it right the second time? Thank you all!

If you want part to have flat walls, and part to have vbit walls, then you need to split the project into multiple workpieces… this project is a tad more complex, but covers the process you’ll need to follow with the multiple workpieces…

I do just alot of my projects using this same concept, so check out the flat video too. It employs this same method (and I don’t cut off the carving ar the end like I did on this one :man_facepalming:)

ALSO if yoh haven’t already, make sure to do the process in the video Furthee up flipping the dip switches and changing the grbl code to lock the steppers with full power.

Oh and to touch on why the lake carve failed… was anything holding the board down? I see and edge clamp there. But that might have still allowed the board to move… having good downforce really makes a big difference in the board not moving a bit…

Also I would turn off ramping for vbits, only use ramping for endmills plunging deep to prevent them from burning and dulling while they are overheated…and always carve pine using raster in the same direction of the grain… also it looks like your depth might be off. Is this the new z axis with linear rails or the old one with wheels and a circular belt up top?