Trimming perfect bound with high bulk paper

[CostaRicaPrinter]

Hello everyone,

I've read some posts here that others have the same challenges we do when trimming high bulk paper - the spine crushes. I'm just curious. How do commercial, large run, printers trim their books? They obviously aren't placing spacers in their guillotines! I have several books on my shelf that must have been large-run productions, and they don't have crushed spines. I'm curious. Please help me out!

BG

 

[lfelton]

Hello everyone,

I've read some posts here that others have the same challenges we do when trimming high bulk paper - the spine crushes. I'm just curious. How do commercial, large run, printers trim their books? They obviously aren't placing spacers in their guillotines! I have several books on my shelf that must have been large-run productions, and they don't have crushed spines. I'm curious. Please help me out!

BG

3 knife trimmer

 

[CostaRicaPrinter]

Hello Ifelton - It doesn't seem to me that a 3 knife trimmer would avoid the problem. The trimmer still has to hold the book, and the spine would still crush. I'm talking about books of an inch or more thickness with very "soft" paper. Thanks! BG

 

[lfelton]

The clamps don't work the same way as a standard guillotine (on our trimmer we have to change clamp plates for certain book sizes) and neither do the knives, although you can get a similar result if you are careful on a guillotine. On a standard guillotine the clamp has to hold the book over the spine to trim top and bottom. You CAN prevent the guillotine from crushing the spine by making a pad from greyboard the same size as the book block less a bit for the spine. The knives also cut in a specific direction to avoid snagging the spine. Again, you can get much the same effect by turning the book over between top and bottom cuts on a standard guillotine.

 

[CostaRicaPrinter]

Yes, we make thick pads for our guillotine, and we cut the right direction. Our final product is good, it's just slow! I understand that trimmers could be set up so as not to crush the spine. You've answered my curiosity! Since we do short run books of many different sizes, I suppose we'll plod along with our guillotine. Thanks! BG

 

[davarino]

That's the reason so many books in the recent past were produced as untrimmed, spine-glued signatures. The purchaser would either hand slit the sides or take the book to the town bookbinder to trim out individually and case in.


This was a very common situation less than 30 years ago with any book printer printing on "papel editorial" in the second world... still the norm in the third world. And 50 years ago it was the norm except for trade edition books in most of the world.

This is one example of advance of technology (perfect binding) and non-advancement (papel editorial) conflicting with each other. Good first-world paper is great for perfect binding. You may wish to reassess whether your processes, materials, and customers' expectations match.

Best wishes.

 

[CostaRicaPrinter]

Hello Davarino,

Yes, you are right. We get great results with bond paper. The high bulk "editorial" is good for export though - because most of our clientele is outside Costa Rica. Shipping is almost half with "editorial". Also, we found a pile of old "editorial" paper, and ran it recently. It didn't have any of the garbage on it like our last batch. Maybe the supplier got a bad batch of paper. We are going to make a small purchase to see. Unfortunately on ONE place imports papel editorial. !! Grrr. Thanks! BG