Press speed for die cutting
We are wondering if press speed plays a part in die cutting. We are working with a windmill and cutting a 43 pt chipboard coaster. We are wondering if a slow end speed 2300 works better than a faster speed 3500+. We are wondering if the speed plays a role in the die passing through the sheet in any different manner or if speed is no real factor
II always run my platens slow. Better to keep the sheet together with less nicks in the die.
i have done long runs where there is a straight cut on the gripper part. So i remove that blade, i can then increase the speed of the press and cut that straight cut on the guillotine as a stack.
Thank you for the feedback. We are not sure if some of the impression strength comes as a result of speed ( i.e. press momentum) or if speed has no true effect. We are cutting a 43 pt chipboard and want to both cut while the same time not over stress the press, the die or me the operator. We view cutting chipboard as running at full speed into a brick wall. We don’t know if it is best to sneak up to it ( slower speed) or slam into it ( higher speed). We just don,t want to look back on this as a should a, could a, would a, after the fact.
Speed should not change the impression. The cutting rule should penetrate about 93-97% of the stock you are cutting/the die rule should not pass through the stock and hit the die jacket. If hitting the die jacket you are hurting something. Get your die cutting help from die cutters.
I ran Hidies commercially for many years. Adjust your impression so that it only just cuts the stock, and to make a nick the best way is to use a piece of old cutting rule and and a small hammer
I don’t think the platen of a windmill carries much momentum as compared to, say, a Kluge. I never really noticed an increase or decrease in pressure (when changing speed) during numbering. Numbering has very minimal contact area thus the impression is sensitive to pressure differences.
With a thick stock like that, you may see the press “load up” before cutting. This is where all the “slop” in the machine is taken up before the cut actually happens.
i would prob use an LCB cutting rule. Long Center Bevel. This provides some pressure relief by reducing the separation between die cut piece, and scrap or skeleton.
Thank you all for the feed back. We don’t lay awake at night thinking up silly questions to ask though it may seem like it. It is our goal to be the best we can at what we choose to do. We click our heels together and ask the wizard ( you folks). You are our heart, courage and brains.
It is stated in the manual that the machine applies the same impressional force no matter the speed… I’ll try and find the page at some point, but I remember reading the sales pitches and factoids in it about impressional strength and how the machine makes the same motion no matter how fast it was going etc etc etc….
In my believe its not a matter of increased impressional force due to speed, the speed affects the stock or paper thats why if possible remove the cut closest to the gripper, and make that straight cut on the guillotine. its a matter of motion that affects the paper swinging around, and also makes an even stack on the delivery table. whithout pieces of paper flying around and jamming the press and the make ready.