Router bit not milling full depth

[beemsquar2]

Most of my tooling is 1/8th, so I have a 1/8th collet - Simples!

Have you measured the tool stick-out before and after cutting? a 1/8th tool in a 3mm collet may just not be gripping properly, especially if it is not fully inserted in the first place..

The collet I'm using is a 3-4mm collet, so I would have thought that it would easily hold a 3.175mm bit. I haven't tried measuring the bit, but I will have a another test tomorrow and see.

[beemsquar2]

What method are you using to zero the Z height before each cut?

Hi Kitwin, I'm using the same method I use for all bits I lower the bit onto a thin piece of paper and set it when I can just move the paper, but it's not pinched. Not the best method I know, but it seems to work well enough. I would love to by a zero setter at some point.

[routercnc]

There are 4 categories of possible issues - electrical, mechanical, software, and 'user'.

I think with your experience that rules out user. As it is OK with other router bits that rules out electrical.

As it occurs with this specific bit then mechanical as other have suggested is possible, the obvious one being slipping up inside the collet. This can be checked by touching off before and after the cycle (paper is fine by the way). If it is this then get a 1/4" collet. Just personal preference but I always match the collet diameter exactly to the tool diameter.

The other one is software which should be considered further. I like Boyan's suggestion of copying a good tool in the library and editing the data to suit the faulty tool.

If that is no good then you can try cutting out a simple square in some scrap, one with tabs, and one without (screw the stock down through the square to avoid damaging the cutter when it breaks free). Ask for the usual 15.6 mm depth in a 15 mm part or whatever and see if the software is getting hung up on the tab part creating a bit of odd code.

I used a sister product called Vectric Cut2D many years ago but have long since migrated to F360, even so I don't remember anything like this.

[JAZZCNC]

Zip up the G-code file and post it. The G-code should tell you everything.? If it says 15.6mm in the code and you have touched the tool off correctly then the length of the tool makes no difference provided it's longer than 15.6mm and you have Z travel enough it should go through the material.! If not then it can only really be slipping in the collet because the other tools are cutting correctly so it's not a mechanical or controller issue.

[ngwagwa]

I find Camotics useful for checking gcode https://camotics.org/

[beemsquar2]

Thanks for all the suggestions guys, it's really appreciated as I've been stumped on this one, I will try some tests today and see if I can post the code here. I will try and set it up as another tool too and cut with and without tabs as when I did a test cut to half the depth of my material it was perfect!

[cropwell]

Hi Kitwin, I'm using the same method I use for all bits I lower the bit onto a thin piece of paper and set it when I can just move the paper, but it's not pinched. Not the best method I know, but it seems to work well enough. I would love to by a zero setter at some point.

My zero setter is a piece of brass bonded to acrylic. The brass/acrylic was turned on the lathe to make the faces parallel and a 4mm hole drilled in the brass for a wire to connect it to the BoB.

I have a macro for Mach3 which lowers the bit (earthed, in my case through the spindle) onto the brass and when it touches it retracts the tool 10mm and sets the tool to Gauge thickness + 10mm, so zero is top of material, bottom of gauge.

If everything weren't packed away whilst I am refurbing my workspace during lockdown, I could send you a copy of the macro and instructions, assuming you use Mach3.

Cheers, Rob

[beemsquar2]

Cheers Rob, if you ever get it out again, feel free to send the macro, that would be very useful!

I ran a few tests today, but I'm still confused. I measured the bit before and after a cut, with and without tabs, it's definitely not the bit slipping. I had 19.06mm before and after. Out of the two cuts, the one without the tabs was better with only 1mm remaining, the tabed cut had 1.6mm remaining. I copied my whiteside compression bit, which I know works, changed the pass over and bit setup to match the 3.175mm bit and ran it again. Still no difference. I even tried making a pocket 11mm deep and it was perfect.
I am at a loss as to what is causing it!
I will try and post the G code tomorrow to see if someone can see any issues with it, but as far as I can tell its correct. I might try just for sanity sake to run the g code for the 3.175mm bit with my whiteside bit in a piece of scrap to see if that cuts through the material to the 15.6mm depth, which might rule our the code.
The only way I can get it to cut all the way through is to set the Z height at 1.6mm below the actual z height of the material, so I know it can cut through.

[JAZZCNC]

I was tired last night so I blaming that for not thinking of this before.!! . . Check the tool table to make sure you haven't got an height offset entered for that tool number. It's about the only other thing it could be if it's not slipping and the code is correct.

[paulus.v]

This is strange. If you want to post the Aspire file as well I can look into it. What post processor do you use? The Mach2/3 Arcs? I can generate another g-code with a custom mach3 post processor to check if it makes any difference.

Check if after finishing the job the Z0 is at the same correct height to rule out missing steps on the Z axis.