Tangential Knife/Drag Knife?

Hello All

I Have a Tangential Knife Router. Less Helped with The Post For My Machine and I now have the Post Set Up and It is working very well.
I did purchase the Drag knife Plugin thinking that this was the closest plug in to my application.
Tangential Knife Is a Rotary C axis Knife and Does not require the Same Moves that a drag Knife does.
But I do like the Drag Knife Operation and tools. As Of now I have found the Best way to set up a job is to Just use the plasma cutting version and Change the name of the tool to tangential Knife.

Is there a better way of setting up sheetcam for Tangential Knife? It just doesn’t feel right creating the job in the Plasma version and the Drag Knife plug in feels better even though I’m not able to get the cut paths I want with it. Customers will be using this and I am Working on the best way to instruct them to set up sheetcam for Tangential Knife. It would be nice to possible have a Tangential Knife tool with the Drag Knife Plugin.

I did try setting up the Tangential knife with the machine type set to router. But being a router, the Tools and whatnot are catered towards spindle and router bit operations.

Attached some picture of Some Practice cuts I’ve done so far and my Post
Any Help would be much appreciated.



Centroid Tangential Knife.scpost (13.2 KB)

I didn’t create tangential knife tools/operations because I don’t have that many customers with tangential knife. I generally just recommend using milling/routing tools.
Do you sell many tangential setups? It wouldn’t be that difficult to create knife specific tools and operations. The worst bit would be coming up with the graphics and icons.

Just when you were thinking about winding things up. Another project…

Heh. Yeah, no shortage of projects.

I Did end up just using milling/routing. When I run the post Processor it doesn’t like the tool to have zero Spindle speed and gives a warning. But that’s no big deal I guess. And the Gcode has Some Spindle speed 0 commands.

Graphics for a tangential knife tool and operation would be nice. And to have no spindle speed or spindle type tool options.

I’m planning ahead but there will be quite a few in the next year.

I’ll investigate what I can’t modify on my end.

Give this version of the post a try. It had a lot of spindle stuff that was not needed. I’m not sure why it was left in there.
Centroid Tangential Knife.scpost (12.6 KB)

Thanks for the help Les :sunglasses:

As of now I have the Post set to Lift at the height of the Material. I Could have a set DIstance for the Z to lift to but I’d like for the post to never need changed. If it always lifted to 10mm and a thicker material is used then the user would need to edit the lift height in the post.


When I set the lift to the material thickness then i fudge the material thickness to the height i actually want the material to lift which is a couple mm above my material.

Id like for the Lift height to be a defined amount above my material thickness. That way I don’t have to fudge the material thickness and the post won’t need changed for a different material. The Post would always lift the defined distance above my material thickness and be right on the money.

Any idea on how I can make this happen?

Setting Zero at the Top Of the Material Gets around my issue. I think Setting Zero at the Bottom of the material was a non convential way of going about it anyways. :mrgreen:

If you find the calculation in the post that is used when liftclearance is false then you should be able to add a constant value to the material thickness there.
I didn’t look at the post, so I’m not sure what the calculation looks like.