Getting smoother routes

what type of bit do I need to get these lines crisper and the floor smooth?

I think this is more of a settings problem than a bit one

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I am using the recommended cut settings what needs to change?

I would be interested in this as well. All of my V-Carve text work comes out pretty crisp and clean but all of my 3D work done with Vetric takes a good 10 minutes with a brush to clean up. These have mostly been test cuts on poplar so I have questioned if it’s the soft wood causing the issue.

Soft wood is harder (pun intended) to work with :wink:

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first of all are you 100% sure your artwork is crisp?
If you did a software trace of a bitmap image you could easily end up with jaggy lines, which would make your cutting result true to the source material.
Second check if EVERYTHING on your machine is 100% tightened. Could be some play in your axes.
maybe compare aggressive cutting depth to a very light pass and see if that makes a difference.

This hobby is all about eliminating variables and trouble solving. Get used to it :sunglasses:

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I’m curious what speed you’re running this at? The other thing is you may do a final pass taking just a minuscule amount (thousands of an inch) and/or reversing the direction of travel. Not sure if you’re using an up cut or down cut or just a straight bit. Surprisingly, sometimes a two flute straight cutting bit will produce better results than some of the solid carbide in my experience. You could also play around a little bit with speed. Best advice I can give is test, test, test. and keep accurate notes.

Make sure everything is firm and that you’ve minimised backlash (any free movement of each axis) as much as practicable without overtightening things.

One source of machining marks on the floor of your cuts, can be from a misaligned axis, so you’ll need to make sure your Z axis is vertical - something that’s perhaps not as easy or intuitive as it sounds.

One method is to clamp, tie or temporarily glue a stiff piece of wire to an old bit. The wire needs to be bent at 90 degrees at the tip of the bit, extend for a foot or so and then be bent at 90 degrees in the opposite direction at the end. You’re trying to make a stiff “pointer” that you can rotate around the axis of the machine’s shaft BY HAND to show any error in your Z axis (imagine if the tip of the pointer was a pen, rotating the chuck of the machine would draw a large circle on your table).

Lower the pointer until it just scrapes across a sheet of paper on the table. Rotate it 180 degrees and check the distance between the pointer and the table. Ideally, you should be able to have the gap between the tip of the “pointer” and table remain constant through the whole 360 degrees. The point at which the “gap” is greatest, is the direction that the very top of the Z axis would need to be moved. When adjusting it, you’d need to move the Z axis sufficiently to close HALF the gap between the pointer and the table.

I know it sounds fiddly, but it can make a big difference if things aren’t quite square.

Another suggestion would be to use the thickest, sharpest, downcut spiral bits you can - thick bits means less flexing, sharp downcut bits tend to produce nice crisp edges.

Another worthwhile suggestion is, once your cut is finished, to rerun the same cut again before you’ve moved or adjusted things. This works really well for simple cuts, but isn’t always practical for really long and complex cuts (unless you’ve plenty of time).

Then there’s always sanding, and sanding, and sanding…

For a smooth “floor” use a fishtail bit.

drawing is smooth all wheels on markerslide are snug router speed is set at 1 I did reduce the depth of cut from 1.2 to .7 its running a test now will see what happens

What I have done in the past is use a downcut bit. I find the upcut and straight bits tend to tear at the softer woods instead of shearing. As it was mentioned before you can rerun the project a second time but change the depth of cut to the full depth. So you make one final clean up pass.

Good writeup. If you’re not into fiddly wire (which does work, mind you) you can build/buy a Traminator, just a more exact method

or you can build your own tramming gauge. like @DavidWestley mentioned, it’s just a bit to fit into the collet, and a bar that attaches to an indicator gauge. You can build these for around $20 with a cheap amazon indicator gauge.