Bit out of control

[lukenavarro]

Can anyone tell me why this happened? It was a pocket cut clearing a hexagon shape. Using “the beast” from idc woodcraft. Material was glued down. Material didn’t move.

[TonyMurray]

Couple of questions that help us is what were the feeds and speeds as well as Depth of Cut or DOC. I am sure @WillAdams will also link his go to’s that a lot of ppl fail to do and that is avoiding slotting.

[MadHatter]

What machine?
Depth of cut?
Feed?
Bit RPM?

All of that will help diagnose the issue.

Assuming that it was a single pass, it might just be too deep for your machine and material being cut.

If not that, then maybe check the set screws on your stepper motors.

[gdon_2003 (Guy Donham)]

As the above posters asked we need more info. Likely your machine lost steps and got off course. Likely your depth of cut was too much or you had a mechanical problem. Give more info to get a better answer. Looks like walnut which is a hardwood. It takes longer to take less per pass but by having to start over any time you saved with aggressive cutting was lost as well as a loss of the material.

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

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…

[Redlander (Tim Jones)]

Looks mechanical to me. Belt machine or ball and lead screw?

The more info we know about the machine your using the more we can help.