Cut failed at the 80% mark

[Jeremy92 (Jeremy)]

at about the 80% mark the y axis got off track up about 1in and x axis off to the right about 2.5in.
for info carbide create/ motion is up to date. i do use windows for design and transfer to a macbook pro using a usb drive.

[WillAdams (William Adams (Carbide 3D))]

Another consideration is Climb vs. Conventional Milling and tooling engagement — where possible avoid slotting and add geometry and cut as a pocket

Making vacuum hose adapters

While cutting up vacuum extension wands for this is expedient, it’s a bit problematic given that Shop Vac recently filed for bankruptcy, was bought at the last minute, and production hasn’t caught up. I need a receptacle for the Sweepy 2.0 dust fitting — one option would be to purchase one from Woodcraft, but Carbide 3D sells blocks of HDPE: which looks to be just barely big enough for things to fit. Measuring the hose fitting I get a diameter of ~63.5mm — offsetting that twice we arrive at…

and/or

Adding geometry to cut as a pocket with a finishing pass

One technique which is often suggested to avoid slotting is to add geometry around a part which one wishes to cut out and cut as a pocket down to tab depth — here’s one technique for that. In this case, the project is a bevel gauge which will be cut out of 0.0625" (~1.5mm) thick aluminum: [bevelgauge] Due to the narrowness of the angles, an 0.03125" endmill has to be used, so after importing and scaling the file (we will be cutting out one which is 3") we select the perimeter and offset it tw…

and consider leaving a roughing clearance and taking a finishing pass.

Best Bit for full cut through

One which has a cutting flute length equal to or greater than the thickness of the stock — pretty much any tool should work. Big thing is the toolpaths — if cutting out, rather than just cutting a slot: [image] Offset to the outside by endmill diameter plus 10% or so: [image] [image] [image] Then cut as a pocket: [image] down to tab height or the penultimate pass: [image] then move the contour down to below the pocket and start cutting at the bottom of the pocket: [image] and…

[Bozo (Bozo T Clown)]

One guess among many possibilities: the material looks thin. It may have been secured well around the perimeter but not in the interior and this allowed the material to flex (up) when the upcut bit engaged that area. As the material flexed up, the bit was ‘grabbed’ by the material and this caused enough radial force on the bit to pull it off the intended toolpath with resulting lost steps at the stepper motors ( this will often pull the bit down in Z as well, making later cuts too deep). These lost steps effectively introduced an offset to the remaining cut.

A few things to try:

• If the material is thin, you could try using double sided tape to secure it better.
• Reduce the tool engagement by decreasing the depth of cut or feed rate.
• Use of a down cut bit may help since to will tend to push the material down rather than lift it.

Cheers.

edit: after staring at your posted images, I do not think the explanation above is correct. If it were, then there should be a cut engaged in the material which is at first correct and then drifts off. I do not see this in your images.

[Bozo (Bozo T Clown)]

Can you post the c2d file or the Gcode used to cut the sign when the problem occurred?

[Bozo (Bozo T Clown)]

My second guess is that something interfered with machine movement during cutting of the s in Partners (maybe a clamp got tangled up with the dust boot causing lost steps). From that point forward the cut was off. If the file is posted, the toolpath may help confirm this.