Perfect bound book bodies have a wave/wrinkle after being bound

[brian@cec]

Perfect bound book bodies have a wave/wrinkle after being bound. Not every one, not every run. This particular book it happened 1 out of 10 times, randomly throughout the run of 200. We use a Standard Horizon BQ-270. Any Ideas ?

 

[effeegee]

Can't really tell from one picture. One location? flyleaf only? Is there is any consistency to the location and extent into the book? Had a serious jam on the machine?

Most likely cause is the spine is moving sometimes in the milling or nipping station and one possibility is the clamp may not be closing fully or evenly sometimes obvious if you can pull one end up more easily than the other. If it is always on the same side (in relation to rotation of the milling blade) the spine is moving in the milling station. Look to see if the spine is a little twisted too - it may be disguised by a uneven glue thickness. Try just milling spines to different depths if you can see unevenness … will be exacerbated by bluntness dragging rather than cutting.
Another possibility that the nipping station is set too hard or high - squeezing the book up when it closes and appearing when it is unevenly clamped.

 

[Eighty7]

Another thing to check on the BQ-270 is for a sheet metal support on the lower front clamp of the carriage clamp. It is made somewhat like a piece of angle iron, but it is made of thin steel. It's maybe 3/8" in height and the full length of the front of the carriage clamp.

It is held on by four screws and is visible (and removable) when you put the carriage clamp over the nipper/cover clamp station, you have to get on your knees and look under the carriage clamp.

Essentially, this piece of sheet metal is an expendable item that is meant to bend or get mis-aligned if an improperly loaded book block gets through to the nipper. Once bent or mis-aligned, book blocks don't clamp well when the cover is clamped on as this sheet metal piece is a lower extension of the carriage clamp.

The part is called a sub-plate and is available from your local Standard Horizon service provider.

 

[jwurts4]

looks like nipper timing to me......or too much glue on your side supports in your saw station (built up from rebinding books).

 

[typenut]

Make sure the grain of the stock all runs in the same direction

 

[cosmo]

its just the way the operator is loading the book in

 

[WhatsInaname]

Not sure if you found a solution - but we are having this same issue on both of our small binders, all of a sudden. They are PBS 6000's.