Problem with dies

I have a problem with dies, it was not important but in this case i´m having several problems.

My question is the following, when I´m cutting dies and i want to make them with trims i have a problem after the roughing, where the material breaks, there appears some material, here in spain we call to it hair, the way i use to remove that material is when I´m finishing the die, I entry in the piece with a circle tangent before the profile, the radius of the circe is around 0.5mm, but it is not enough yet, becouse still appears a small line, what happens is that when my customer uses the die in his pieces appears that line, the material of this dies is hard steel, but it happens to me also with tempered steel.

I cannot feel anything touching that line, also it´s not posible to measure it becouse it seems hat there is not anything there, but when the die works the line appears.

Can anyone help me?

I use an ONA AX machine with Bercocut wire.

Thanks in advance for your help

Best regards

If your die opening is symetrical try X/Y mirroring your skim passes so that their entry is on the opposite side, this should eliminate the entry mark.

We cut a lot of dies on our Charmilles Robofil machines, and we use Berco also. We never enter on an arc and never have a problem with entry marks after a few skim passes, even without mirroring them.

Perhaps the tangent points of your entry arcs aren't meeting?

It would also help to know what kind of die you are cutting. Blanking, extrusion, form, shave, etc.

it´s a extrusion die for cupper.

In my final piece it´s almost posible to see any mark, the only thing you can see is a small line, i have measured it an the deep of that line is around 6 micron(excuse me we speak in mm)a very thin mark but in the final work it makes the pieces not wrong but yes with a mark.

thanks for your reply

roonie, I'm gathering that the line in the die opening is deeper than the rest of the profile (negative stock). This comes from (most likely) when you enter and exit on an arc, the entry and exit arcs both come tangent to the profile at the same point. This means that this specific point on the profile is being passed over TWICE as many times as any other point on the profile. I would try this: Enter and exit starting the arc .381mm (.015") off center from the theoretical tangent to the profile, but use a .421 (.0165")radius when coming onto and off of the profile. If there is a line of negative stock, increase the entry-exit radius, and if there's a bump of positive stock, reduce the entry-exit radius. The tool path will appear to be leaving a slight bump of positive stock in the die opening, but considering that this point will be passed twice as many times as all other points, it will have more overburn, and the slight gap in path will actually produce a flat section where you will not be able to see or measure where the wire entered or left the geometry of the die. I've used this method for the last 17 years, and it works. Good Luck!

Sounds to me like incorrect placement of your G41/G42 command I have never run the machine you are running but, Im betting there is some sort of offset code that the machine uses try moving your G41/2 code up one line in your cut file