This is a simple guide to how I surface my CNC spoilboard using Vectric VCarve.
First, let me start with their are a dozen different programs that you can do this with. I chose Vectric’s line after going through a few others, Easel and Fusion 360, just to name a couple. To me it is the most versatile, with the least hassle. This concept, really works for most softwares though.
I should also add, if you watch my video you will notice I am using Aspire. Aspire IS VCarvePro with 3D modeling. You don’t need the extra features of Aspire to be able to do this. Flattening your spoil board in this manner is super easy.
Step-by-Step CNC Spoilboard flattening with VCarve
- Boot up your Vectric software, whether it be VCarve, VCarvePro or Aspire (I do believe the lower levels below VCarve will do this too). Cut2D, and Cut3D should work.
- Create a new file. I set my dimensions to the exact dimensions of my cutting surface area. For my Onefinity CNC, that is 48″x 32″. I then set my Thickness at .75″ as that is the thickness of my MDF spoilboard. This thickness, it arbitrary as we are only skimming the top. Make it single sided, Z-zero to the material surface, and standard resolution. Click OK.
- Next, click the “Draw Rectangle” tool and a new window will pop up. Set the Anchor Point to your preferred location, I like bottom left. Make the corner type “Square” and then set the size to your spoilboard dimensions. I personally like to set an extra play in my dimensions so I do 48.3″x 32.3″. The concept being that your bit will have more overlap on the surface board making it a truer flat. Click Create. Close.
- Pick the Transform Mode tool and select your Rectangle. Click the Alignment Tool and click Align To Material (Center). Close.
- Go to the far right and click on the Toolpaths pullout. Click the tiny Push Pin icon, this will keep your Toolpath pullout from dropping back out.
- Click the Pocket Toolpath. I make two distinct different spoilboard flattening files, one that takes a decent amount, one that just takes the surface. As you get better, you will see the advantage of the latter.

Pocket Toolpath
Make your setting for the initial (deep) toolpath the following.
- Start Depth 0.0 inch
- Cut Depth 0.025 inch
- Tool (select your surfacing bit – I use the Amana Tool RC-2265)
- Double Click on the bit to pull up the bit information screen. Under the cutting parameters, I reduce my bit from 80% stepover to 55%. This means the bit will pass over the same area more. Normally I don’t mind a higher stepover, but it this instance, I want my spoilboard perfect. Lower stepover helps ensure it is flat. You could also increase the Feed Rate for 100imp on this bit, but for me I generally don’t. Slow is Smooth, Smooth is Fast. Click OK.
- Passes. One pass is all that is needed. You can Raster or Offset. I Raster on the 0.025 file, Offset on the 0.01 file (helps me visualize the different files. No Raster Angle, Profile Pass – Last.
- Ramp. You don’t need to ramp, but honestly why not. It will give you a split second to hit STOP if you make a major mistake and see it as the program starts (for instance, your XY coordinates are way off). I ramp for 1 to 3 inches.
- Pocket Allowance, 0.0. No need to check “Use Vector Selection onto 3d Model.”
- Name your file. I try to be as descriptive as possible. 48×32 spoilboard 0.025 RC2265
- Click Calculate.
I am an affiliate marketer, but I only suggest tools I actually use and like. I will not suggestion something that is no good.
With that said, I love Amana Tools and the RC-2265. You can read an article about spoilboard flattening bits I wrote, HERE.

Preview Toolpaths
Honestly, you don’t need to do anything here. I do normally watch my file run sped up to about 75% speed, but really you just need to verify the end product, and with a spoilboard it will just be a flat surface. Press the play button. If it is correct, you can click Close.

Save your Toolpath
Once everything is set up. All you have to do is Save the file.
- Click the Disk (save) Icon. For a file this simple, I always just do the Selected toolpath.
- Make sure your machine is selected.
- Make sure your Post Processor is selected. I use GRBL (inch) (.gcode). It is one of the older and simplest Post Processors, and it doesn’t fail me.
- Click the Save Toolpaths button.
- A Windows Save As window will open, select where you want it located on your USB or Computer and click Save.


Congratulations, you just made a Spoilboard Flattening file!
Now go back and make the same file, but instead of 0.025, do one that is 0.01 inch. Having both will come in handy, I promise. I will post the entire video showing start to finish, HERE.
Make sure to check out the rest of my website and blog! My store has many of the common items I personally use and the WHY behind it.
Have a great one!
Royce
Hill Country CNC & Woodworking is an affiliate marketing business, but it is one with ethics and morals. We only promote the items that we use in our daily business. Let’s help each other! I will give you my experience (and discounts sometimes) and you can help me grow.
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