Final tool pass slightly raised

My last project had an issue with my final 1/8” flat end mill was slightly raised compared to my other two tool passes. File was built in Vcarve Pro and gcode exported using Vcarve (Shapeoko processor with tool change).

So, is something off with my Bitsetter? The other tools were dead even in their depth. You can see the small webbing area between with the uneven depth.

(did you forget to attach a pic ?)
It could be lost Z steps, what Z axis do you have and could you post more info about your toolpaths and feed and speeds ?

I didn’t forget to attach a pic, it’s just the forum is not working properly at the moment.

(just testing image upload)
image

Weird…maybe try editing your post / re-uploading the pic ?

image

Looks to be fixed now? Here’s the image.

I’ll post other data shortly! Thanks

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Maybe also check your BitSetter manually to see if the plunger movement feels smooth.
To rule out (or incriminate) the BitSetter you could maybe try and do a series of tool changes (using Change Tool button) with your various cutters, without running any job, and jog manually to stock surface each time to check whether it’s at exactly Z=0 each time, or slighty offset.

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Ok, cool. I’ll do some testing. Thanks!

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Here’s my 1/8" endmill speed and feed. I did not adjust anything outside of this in CM. My first tool, which I used to the clear the bulk, was knocked down to 50% speed rate in CM, as my initial test on some hardwood caused lost steps. This seemed to work really well.

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Yeah nothing wrong with those settings, so checking the bitsetter behavior outside of a job is probably a good next step

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What size shapeoko and which z-axis? Is the bed fully supported? What size was your clearing bit? I assume it was a 1/4" endmill. Did you use upcut or downcut endmills? Did the raised portion occur in a certain spot or across the whole work piece? I have dealt with a similar issue before.

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1” planing end mill (ran at 50% feed), then 1/4” End mill for 2nd pass (100% feed). Both those are dead even. The 1/8” is the issue (100% feed). Leaves a small “ webbing” between lettering or designs.

I have XXL with Z-plus. I run bit setter and a bit runner. I have additional supports under the bed of the machine. Flex isn’t an issue. The stock is jointed and planned to exacting thickness before going on the XXL. Have t track on top original waste board and a threaded waste board on top that, all of which have been properly flattened. Also the spindle is trammed (Makita)

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Thanks for the info. I have had my issue originate from some flexing before and eliminated that as best i can (down to v-wheel flex). I asked about the upcut vs. downcut because I have had a similar issue where if I was pushing a higher-ish chipload on say a 1/4" upcut and then switched to a 1/8" downcut (with also a higher chipload) that it would cause just enough deflection due to the opposing cutting forces to cause an identical issue to what I am seeing in your pictures. (But your post info says your not pushing that chipload very high, so probably not the issue.) I have also had an issue where a 1/8" clearing followed by a 1/16" clearing are spot on, and then step down to a 1/32" bit for a detail pass (all endmills used were downcut) that actually goes just a smidge too deep. I “remedied” that by setting the 1/32" pass to cut .002" less in depth compared to the other clearing paths. Might be able to do the opposite in your case and program the 1/8" bit to cut a bit deeper to remedy the problem

edit: And you might be surprised by the amount even the best secured xxl can flex/deflect with the thin sheet metal axis plates and vwheels. easily seen if you jog an endmill down into the wasteboard without having the router turned on (that is with an HDZ or ZPlus, belt drives just skip teeth)

Thanks for the reply! Oh yeah, anything is possible, hah. Both bits are upcut bits. I’ve yet to test different end mills as Julien suggested. Hopefully tonight. Have another project to run, so I’d like to get her dialed in beforehand.

I’m fairly new to using Vcarve Pro, so my initial thought was I missed something there, but nothing seems to be out of order. So bit setter was my next guess. I’ll report back any bitsetter discrepancies.

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Ok, got some time to test. It’s not bit setter. I used new bits (same bits as previous job, but unused) and it’s dead on 6mm above Z zero. But! Looking at my endmills, my 1/8” end mill had a small amount of buildup caked on the end. If something like this was present during the bit setter stage, that could possibly explain the difference?

I’ll make sure to give my bits a good once over and stiff brush before throwing them back on the spindle.

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Possibly. I use acetone on a cloth to wipe the endmill tip (careful, sharp edges…) whenever I cut through tape & glue and there is some residue caught between the flutes at the tip.

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