nicking on small saddlestich books

[Mike C.]

Anyway I can prevent nicking on a 48pp plus cover, 60# text with 120# cover, 5.5x4.5 saddlestich book? have tried everything from new resharpened knive to brand new knives to changing the cutting angle of blade, and we are still getting a nick on head and foot. It is a Muller Presto saddle sticher. Any suggestion would be great!

 

[LoganBlade]

change the blades? most nicking i find is the blade is damage. IF the nicking is in teh same spot then I think that might be the problem

 

[apalko]

It may be a little late for this job, but you could try printing a cover with the opposite grain direction from what you have now. It often helps.

Here's another tip that could help you to salvage customer production samples for the job.
Trimming Thick Saddle Stitched Books
It's not a perfect scenario but it might save the job. Or if it's a short-run job you certainly can use this technique.

Unfortunately when you reach a saddle-stitched book thickness of about 1/8" or so, (and it seems you are there) the odds of getting a nick at the spine go up substantially.

 

[ondemandbindery]

A quick way to tell about the condition of your blades is set your timing and face cut as if you are trimming a large book. This will put the book position in a different place in the trimmer and if done properly you can probably get to a spot in the blades which have minimal wear. This is a quick way to see if you truly have a blade problem. Unfortunately, this most likely will not be the case......

I have seen many an hour burned down in a Bindery to tackle this problem you are inquiring about. And the list of what you have tried is that and more from my experience and at the end of the day nothing really made a huge difference. So why does this problem seem to exist more on smaller books versus a larger format say for instance like a magazine size? I personally believe it is the aspect ratio in regards to the amount of clamp holding the book. The chipping is from the book in a fight between blade and clamp IMO. There is just not enough book under the clamp to be held in place. Someone else may chime in here and speak differently and if so I would like to hear their story...

And if you are processing a moderate to high page count as Andre said this risk will certainly increase also. One thing I have noticed that has made a difference is when signatures are run through a Pressing Unit on a folder. Removal of air helps with chipping and backs up my theory about the clamp fighting the blade.

To be honest what I have seen in most cases where the customer is sensitive about this is the Samples are cut on a Flat Bed and the bulk of the project is processed through Binding. Your problem unfortunately is just the nature of the beast....

Good luck,
JW