Sign project, yeah I know, another v-bit carve :)

I’ve had my CNC for a while now but I’m finally getting around to using it now that I have space in my new house. I specifically built a “Nerd Room” in it. The architect had no idea what that meant :slight_smile:

Anyway, I made a sign for my wife and now I see what everyone’s talking about. I now have 5 more to make for her friends.

I know it’s not the most exciting project ever, especially compared to the boats, arcade cabinets and speaker enclosures that I’ve just been reading through, but baby steps, right?

I got some really old oak from a guy in town who was tearing down an old fence he had. It’s cool that right below the dark beat-up surface is still really nice wood.

I made my MPCNC a bit on the big side and I was able to cut the whole sign in one go using a 60 deg V bit. However, the wobble in the middle was definitely noticeable and some of the middle letters weren’t as clean as I’d like. I also didn’t do a finishing pass for the thicker part of the FALL letters as I haven’t quite figured that out yet. I just used a chisel to clean it up and then stuck a little white paint on to make the letters pop better.

I recently figured out how to make the Happy letters thicker in Inkscape, so that would have made the bit cut deeper. I’m hoping I could do the next one without needing to paint it as I like the pure wood look better.

Hopefully I can start posting more exciting projects soon :slight_smile:

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Looks great!!! You are your own worst critic.

The pointers I can give you from these pics. You have a very large build…that just means you need to take it easy. I know it doesn’t seem like it when compared to doing this by hand but you are taking HUGE cuts with that verly large diameter VBit (typically we use a 1/8"). That means your build is pretty good. V bits doa lot of cutting with the tip that has an extremely low RPM so essentially you are just dragging it through the material much lighter passes are need as compared to an endmill. You can use carve, and set the setting for a 4th of your overall depth, and the machine will cut the letters in multiple passes and much less torque. So the depth per pass to lighten the load and the finishing pass to polish the edges when you are done.

1- This is depth per pass, divide your total depth evenly. So if you are doing 15mm total, try 5mm per pass, or 3.
2- The finishing pass should always be the total depth to give the best edge, if it is really deep you might need to slow the machine down to compensate.
3-This is how to set the finishing pass thickness. Should be small, typically we cut less than 3mm at a time so I do a 10th of that or a little more. The idea is thick enough to contain all the imperfections, but thin enough to impose very little load on the router so it cuts extremely accurate.

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Thanks that’s really helpful. I was doing 1mm depth per pass which took forever but maybe that’s why I got some kind of results in the middle still. I need to put in some support posts in the middle too I think, or just do a series of mills very close to the origin and move the board each time.

The issue I had in the end was that there was a central ridge in the wider parts of the FALL letters as the V bit cut on both sides of it to cut to the edges. What process do you normally use to clear out that ridge (easily seen in the middle of the Ls)? I just used a chisel and did it manually but I wouldn’t mind swapping bits and doing a second pass of some kind. Or doing that first to clear out most of that internal cavity so it’s easier on the V bit.

What process do you normally use to clear out that ridge (easily seen in the middle of the Ls)?

You can increase the maximum carve width.
This whole video is worth the watch but 8:50 mins in is exactly your issue. Mostly Printed CNC Part 12 ESTLCAM V Bit Carving - YouTube

Thanks @Bigburlybug! That’s exactly what I needed. I haven’t cut another one yet b/c I need to find another piece of wood but after previewing it in Estlcam, that appears to be what I needed. Thanks again!

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