MDF and Small letters

Ok the sign looks great, BUT you can see on the T of trade and the M on mark the bit more less ate them. Spindle speed is set on 4 pass depth .015 step over 34% IPM 50 PPM .20 using a 1/8 end mill.DSC02561DSC02560DSC02562

Why use 4 on the Dewalt? You should be at one.

And that font might just not carve well.

I’d try lowering the Dewalt speed for sure.

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So the rest of the settings look ok?

V-carving would change the look of the sign.
brunswick_lg2

The other option is to use a 1/32" detail bit and run it first, then hog out the remaining with your roughing bit.

Ok I will give that try tonight, building another shed while the weather is warm.

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I have a Tapered 1/32 ball.

I use 1/32" endmills, but the idea would be the same.

It’s a ballnose so unless your software accounts for that, it may not do what you want.

I’d do this as a 2 stage carve.

First stage using a 1/4" bit and then using either a 1/8" or 1/16" bit to get the details. This should allow for letters to not be damaged.

You can also decrease the depth you’re carving. How deep is that going?

I’m suggesting what you are, only in reverse. I’ve found that with brittle things and soft woods, such as cedar and sometimes pine, I get much better detail if I run the detail pass first and then let the larger bit clear the rest away.

You’re relatively unlikely to have a bunch of chipout when cutting a profile but the larger bit can easily tear out a larger piece than you intended, and if that happens, your detail pass after the fact won’t do anything for you.

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Yea what he said…I’ve noticed some of that on cedar.

Just be careful with Easel multi-stage, the last time I did a detail pass, it took some rather generous assumptions that the roughing pass was done first and did some rapids with the bit below the work zero…which is fine if the area had been cleared previously but if not…bye bye bit!

I wish VC would allow 3 stage hogging. There have been times where I needed to use a .25" bit to hog out, but it can’t get into some nooks and cranny’s I’d like it to. Using a 1/8" bit would take all day, but gets into the nooks and cranny’s. I’d like the progression of 1/4 -> 1/8 - v-bit (or similar progression of smaller bits).

You can do it in 2 toolpaths.

1st toolpath is 1/4" large area clearance, regular 1/8"
2nd toolpath is 1/8" large area clearance, Vbit as the regular bit.

Save the 1/4", 1/8" and V-bit Gcode and run those.

How can this be with toolpath #1? It has to know there is a vcarve at the end, but no v-bit is being used. I’d think you’d be in danger of having toolpath #1 clear out some material that would be needed for toolpath #2.

Toolpath #2 would be a v-carve path with clear out bit… no problem there. Wouldn’t you have to define toolpath #1 as a vcarve path, too? I’d think a pocket path would mess it up.

Please elaborate further.

If you use the actual Vcarve toolpath, I believe that the chain breaks down because of that. If it’s just pocketing it’d work.

There might be a method using the Vcarve offset value.

I’ll look a little more into it tonight.

I ran into the chipping issue with cedar. I lowered the height of the letters to 1/16" and it worked out much better

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Depth of final would have been a little under .50 if I hadn’t stopped the run. When I tried to put the .25 in it said it was to big. The 1/8" bit i’m using is a compression up/down spiral. I wanted the letters to stand way out for the sign, going to change it to .25 depth. Glad it was just a trial run, Customer wants it in wood although I don’t know why as it’s being painted.

The only thing I was running on the Rough was the Profile cut though on this. The tear out on those two letters started with the second pass.

Even the preview is showing the chip out on T and M on this one using

Looks like a tracing issue. Was this traced in Easel?