CNC drag knife
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- เผยแพร่เมื่อ 22 เม.ย. 2017
- Drag knife cutter for the CNC machine and a cardboard plane.
DIY cutting tool, Vectric G-Code.
Drag Knife on Grabcad grabcad.com/library/drag-knife-6
Plane on Grabcad... grabcad.com/library/cardboard... - แนวปฏิบัติและการใช้ชีวิต
God bless u kind sir. I was looking for a laser module to cut stencils in my cnc router. God bless you! Keep up the good work!
I have a professional flatboard cutter at home, they use a micro stepper at a 4th axis to spin the blade. In your case its crucial that the retract-height before direction change is perfect! So before direction change lift the blade up to ~0,5mm still into material, go 0,5mm forward and lower it again. You can also setup the new direction on a waste part outside of the material. Another improvment is to create a manual toolpath with splines and add an "overcut" to it - aka start earlier outside the closed shape and end later. If you want to go under the min radius you have to use oscillating blades at aorund ~10° cutting angle
I never used this type of cardbaord before, keep going - cool project!
+Friedrich Kegel thank you for the helpful information! I will use the cutter this way until i have my CNC controlled spindle as 4th axis. And i will check out these oscillating blades you mentioned!
Hi :)
Wow. Pretty neat. Looks like that without spindle orientation, definitely needs a sacrificial spot and some additional toolpaths to orient the knife. Nice work. :)
+gredangeo with more toolpath experiance, i could have perfect cuts, also without spindle orirntation. Its an interesting and nice challange to get it done perfect.
Please, explain me how do you do the spindle orientation? Tks
I use in Vectric, the Drag knife option. Make extra vectors to orient the blade before starting the shape, then the blade will follow the path due the offset from the center
@@3DMeister Oh. That's pretty cool.
nice tool! there are so many things you can do with a cnc! impressive! your video style is improving too! keep up the good work!
+Six tus thank you! Stay tuned for more tools and videos!
I already posted this on reddit! Hope you dont mind!
www.reddit.com/r/CNC/comments/674je1/diy_drag_knife/?st=J1VX6SZ9&sh=37dd140d
+Six tus thank you for sharing!
may be you can do it with tangential knife ?
what music is? awesome video
I like it.
The most expensive paper airplane in the world, A Guinness world record.:)
Hihi, this was one of my trainings projects in machining. After building this first machine ever, i had to learn all the possibilities in gcoding & tooling.
3D Meister
I'm looking forward to receiving my drag knife. Not spending 350.00 US though. Hopelessly insane to spend that kind of money. The engineering just isn't there haha.
Good stuff thanks for sharing! What was your final blade tip offset from center of rotation? Also whats going on with that blade, looks like you have ground down the back edge?
Thanks. I made some tests with the shape of the blade but that was not helpful. The high point of the blade cutting through the material has to be on or behind center, a flat angled blade with the tip further away from the center can be close and e steep blade can have some distance. And the distance also depends on the material thickness
@@3DMeister So the leading edge of the cut (and so the entire cutting length of the blade) needs to be behind the center line, makes sense. If I am understanding what you are saying, then the offset from the leading edge of the cut, to the center line, depends a how steep the blade angle is. I guess in general if it is a very steep blade, and very close, then it becomes a bit less stable and more affected by variations in the material being cut, like I think I saw the blade wobbling a bit in your vid when going sideways over the corrugations. Useful though, and good to think about, thanks again!
Great Video, explain one thing to me, how do you do the positioning of the blade? Does it use a fourth axis? I am looking for everything that is place to do this position but I can not find it, if you can explain me thanks. Thank you.
Thanks. The knife turns freely with the tip behind the center. You can turn the blade with the tip on the material and a xy movement to the desired direction before cutting through. Vectric has a drawknife mode where you can chose some options.
Dragging a rotation device behind center point is called "negative castor" . Same principle used when setting castor angles for a grocery cart and your car. The more negative castor induced, the more the drag angle will want to straighten out. To much however will cause the blade in this case to not want to turn quickly enough in sharp corners, hence why a sticker plotter for example doesn't induce castor at all, but rather relies on cutting blade angle. For thicker media, you would use a 65 degree cutting blade so that it doesn't pull the substrate up in corners. The down side is the blade will need replacing more often since a steeper angle of edge will dull more quickly. This is why most sticker (thinner material) typically suggest using 45 deg blades.
I have a bunch of decorative Stencil designs I created. some are as big as 18 x 24 inches. I want to produce them on 1mil Mylar for strength. They are far more intricate than that plane design though. I'm worried that a laser CNC might burn them but a blade cutter like this could be just the thing.
Yes!, as long as the material can hold the cutout structure or better with a vacuum table. I think laser can create nice and fast cuts with an air stream.
Hello! How does he turn? Software or axis movement?
Only Axis movement maneuvered by the dragknife app in Aspire Vectric Software.
Hallo, Habe jetzt auch Angefangen mit einem Schleppmesser und der erste versuch hat auch schon soweit geklappt. Aber kannst du mir sagen wie man die Anfahrwege beeinflussen kann z.b. wenn man ein Loch ausschneiden will das er von innen an die Kontur fährt und wieder nach innen die Ausfahrbewegung bei mir sieht es komisch aus. Weiß nur nicht wo ich es einstellen kann. benutze auch Vectric-Aspire. Wäre nett von dir zu hören übrigens schönes Projekt sieht super aus. Gruss Frank
Hallo, ich hab das program grad nicht zur hand, aber ich glaub man muss die Vektoren so zeichnen das eine Gerade od ein kleinerer halbkreis zum Kreis geht, der dann nicht geschlossen ist . Lead in lead out sozusagen muss man teiweise selbst zeichnen. und ausrichten kann man das messer auch mit kurzen vectoren ausserhalb.
Hallo, Danke dir für die schnelle Antwort werde ich mal Probieren.
Is that on a vacuum table? Very nice!
No, but I made one. You can see it on Instagram in action.
Will changing the blade to a long thin type help the cutting?
not necessarily, its more about the distance of the tip behind the center related to the thickness of the material to be cut. So that the blade can be guided like a Finn . 45- 40 degree was nice to work with
Sou do Brasil. Como adaptar drag knife na router?
Hello, I use a program called Vectric with a dragknife tool path option, to generate a cutting G-Code
@@3DMeister how to install this toolpath? Where can I find this dragknife toopath?
@@elsonpcelson4671 You need the app Aspire by Vectric the tool path creator is under Gadgets. Also somewhere in Fusion 360. There are add ons or other Applications for sure
There is a machine called xacto knife combined with a ruler and the most sofisticated tool called hand they can do this job in seconds
thats oldscool
Why do you use 3 bearings? Could I get away with one?
Use at least 2. the blade is more stable and the bearings will last longer.
check out Brian Oltrogge on youtube for his dragknife build, he has plans on his website $5, well worth a pint!
Hey if you have the firmware do send it
Hi, this is all i have, you can download the contour, and than make this with Vectric;
grabcad.com/library/drag-knife-6
grabcad.com/library/cardboard-plane-1
I think your gantry is not rigid enough for this operation hahaha
:) haha, you got to know what your machine can bear.
No, I had no imagination about what can be done with CNC, had to try this for the educational purpose.
@@3DMeister Yes that is great! I am looking to make a drag knife for my machine so your video was very helpful. Thanks!
@@filowfulwaffle Super!
Can't talk huh?
I have nothing to say….yet.