design specifications
The following is a selection of helpful information covering pre-press guides and production guides for covers, jackets, spines etc. Additionally you may access our customer ordering site at claysonline.
Guide to digital prepress
At Clays we use an Esko Digital PrePress system for all plates. All data received is converted into our own format for imposition and storage purposes. All output is direct to plate.
Prepress equipment
We use eight Compaq workstations through which we process your orders to produce a factory works instruction and your data, to produce plates. The network, which includes six platesetters, is supported by five servers. All data is archived and can be retrieved and manipulated for future reprints in any size.
Digital data
We accept digital data in the form of pdf files. Digital data can also be supplied on discs, as email attachments sent via your account controller, ISDN line - 01986 895031 or via our ftp.
How to login to Clays ftp site on a pc
Enter the ftp site address in the address bar of your browser, ideally IE. (Note: Firefox, Safari & Opera browsers will not work)
ftp://clays.ftpstream.com
If you’re not automatically prompted for a username and password, choose 'login as...' from the file menu. Enter your username and password, if you require a username and password you can simply request this by contacting your account controller. You can now copy the files by "copy & paste" or "drag & drop" in to the window.
How to login to Clays ftp site on a Mac
If you’re using a Mac you can access as follows:
> Click on GO menu
> Connect to server
> Enter ftp address ftp://clays.ftpstream.com and click connect
> Enter username and password
> You can now copy the files by "copy & paste" or "drag & drop" in to the window
Submitting digital data
Before submitting any digital data please ensure you have read through the details in the PrePress Guidelines section (below). Include a copy of our order information form (Microsoft Word, 40kB) with all data.
Prepress guidelines
Covers
See the Prepress Guidelines for more information about how to supply data to us.
Printing conditions
sequence: black - cyan - magenta - yellow
densities: black = 1.8, cyan = 1.4, magenta = 1.35, yellow = 1.00
Please note: All proofs to match for colour should be unfinished.
Paperback cover dimensions
Trims:
2mm tails
3mm foredge
8mm between heads
Laydown:
head to head
spines aligned with each other
centrally placed
non-bleeding lettering or design withdrawn 4mm from trim lines
spine width equals book bulk
Paperback Cover Layout
Download Clays Paperback Cover Layout

Cover for case
Printed Cover For Case Dimensions
Allow 18mm all round for casemaking turnover and extend the image that needs to bleed into this area.
Download Clays printed cover specs - Flat back

Download Clays printed cover specs - Rounded backed
Jackets
Printed jacket dimensions
min. flap width: 70mm
max. flap widths for standard format:
large crown: 109mm
Demy: 115mm
Royal: 130mm
Allow 3mm trim/bleed all round. Maximum jacket width, including flaps is 600mm
Maximum flap widths for all other formats should be no greater than 20mm less than spine to foredge trim size. Any image that is to bleed beyond the front fold should be extended by a minimum of 10mm.
Download Clays jacket specification
NOTE: Diagram to be used in conjunction with "Design" information available on web site. Any jacket design which finishes on foredge edge of board (i.e. image/colour does not extend to create colour turn ins).
Please consult with your account controller before proceeding with artwork.
Additional information
Blocking/embossing
Jackets - maximum blocking/embossing width is 530mm
Covers - no restrictions as regards to area
Spine widths for covers & jackets
To calculate the spine width for a cover or a jacket please enter the book specification into our spine width calculator.
Guidelines for brasses and artwork
We’re able to accept files for artwork or use sharp definition laser copy or bromide paper. Make up artwork to correct size and positioning as for final case design.
Supply each blocking colour as separate artwork and complete as one piece for spine and front of case. It is recommended that spine rules and spine panel widths are 5mm over theoretical width to allow for possible variation in extent or paper bulk. These can then be cut down to final size once final bulk is known. i.e. paper book block + 9mm for the case round + 5mm extra. Spine text lettering should be no wider than the calculated paper bulk (use lowest likely page extent).
For solid panels surrounded by blocked rules, panel depth and width should be 1mm less than the outer dimension of the rules. This helps register of the rules over the panels and also avoids the panel colour bleeding under the rules. Don't forget to send a layout of the artwork marked up for colour and positions required from edge of final case.
Stickers
Specification:
General requirements: self-adhesive labels, roll-fed; label spacing min 2mm
Reel width: 290mm max. (a) we can accept reel widths of less than 290mm but please make as large as possible.
Reel core: 44mm (b)
Label width: 6 - 55mm (c)
Label depth: 12 - 40 (d)
Label placement tolerance: app 1.0mm.
Stickers per reel: please supply as many stickers per reel as possible, i.e. if the quantity is 6,000 supply one reel of 6,000 in preference to 2 reels of 3,000.
Orientation of labels on reel:
Self-adhesive labels, roll fed
Sticker spacing min 2mm
Guidelines for cover designers
There are certain variables that can affect components during production and though on their own they can be small, they can combine to affect the final cover design on the trimmed book. It is useful therefore to follow some basic guidelines:
Type and non-bleeding images such as logos, flashes etc., should be withdrawn 4mm from book trims.
Spine bulks of less than 5mm should contain no type on the spine.
Spine type on thin books between 5 and 10mm should be 2mm smaller in height than the text bulk. This will help to avoid wraparound type when bound.
Logos and type for wider spines should be sized to give 2mm minimum space either side of the image. This should be increased to 3mm on spines exceeding 30mm.
It is worth noting that spines on sewn books can be between 1mm and 2mm larger than their unsewn equivalents (refer to production if unsure).
Avoid fine serif type reversing from four colours.
Fine reversed rules or keylines in solid colour should be minimum of 0.25mm in thickness.
Kiss fit images need to be spread/choked to give better fit in final printing.
Large panels of black solids will generally have a 50% tint of cyan beneath to provide best density, underlying colours should not total more than 120%.
Avoid high percentage tints printing within large areas of solid colour. 60-70% tint will give better definition.
Do not reverse out foil blocking areas from the print image (unless a drop shadow effect is required). This will assist blocking register.
If fifth colour match is not 'crucial' it is worth considering producing this from four colours.
Be aware that Pantone colours are not always accurately matched by four colour process.
Be aware that Pantone colours starting with a 'C' are for coated paper and a 'U' are for uncoated papers.
Printing black from four process colours should be avoided where possible, especially on spines or trim edges.
Matt/silk lamination over large areas of dark colours is prone to showing a degree of scuffing and marking during the book production process.
House stock
Paper
Our papers are described in terms of weight and calliper. The weight of the paper is measured in grammes per square metre (gsm). The caliper or thickness of the paper is measured in microns or thousandths of a millimetre.
Please contact us for a full technical specification if required.
Minimum/maximum text paper weights
The minimum weight on which we can print is 28gsm. The minimum calliper is 33 microns. The maximum weight is 90gsm and the maximum calliper is 180 microns.
Click here to download clays paper range.
The paper items shown are invariably available for immediate use.
These same products can also be purchased in non-standard reel sizes and/or different grammages and volumes to suit Customer requirements based on Mill lead-times, typically 4-6 weeks.
Please contact your account controller for more details.
Printing & binding
Standard sizes of trimmed paperbacks and cased book blocks unsewn sewn (height x width, mm) (height x width, mm)
A Format 178 x 111 178 x 114
B Format 198 x 129 198 x 132
Demy 216 x 135 216 x 138
Royal 234 x 153 234 x 156
Margins and bleeds
We would recommend a minimum margin of 6mm of white space between the text and the trimmed edge or gutter, on all four sides. Generally we do not recommend bleeds on web printing; however in some circumstances bleeds can be accommodated (for example by using oversized reels). Please contact us for more details.
Extents
For the most cost effective production, final page extent should be divisible by 48 for A and B formats, and 32 for Demy and Royal formats.
Supplying pdf data
We will always process an initial test disc if requested - please ensure the test includes any pages containing half-tones, tints etc.
Do:
provide files as pdf. embed all your fonts.
use high resolution images in the pdf file.
supply no more than one component per disc.
Don't:
use colour images in a file intended for black and white work.
use Adobe 3 or TrueType fonts.
leave errors uncorrected.
supply application files - the Barco system will only accept pdf files.
use lines less than 25 micron in thickness.
Putting the files together
Supply a list of files and the pages contained within them use Order Information Form.
Use logical file names.
Use multi-page files.
Ensure blank pages are blank.
Provide pages in consecutive order.
Supply pages as they will visually appear on the printed page i.e. if printed portrait, should be supplied portrait.
Save as single and never double page spreads.
If proofs are supplied they must be output from the final pdf file. They may be used for reference in the event of problems or queries but will not be checked for content.
If you have compressed the PDF files, please state what compression software was used, and if possible include the decompression software.
Save onto CD/R, 3.5" Floppies, ftp or email.
Details
All pages should be the same size and same reduction or enlargement factor should be applied.
For bled pages the typesetter must set up the page size and include an allowance of 5mm all round.
For production of half tone screens use: 150 Ipi for web; 175 Ipi for sheet fed.
Mechanical diagram tints to be minimum of 7%, going up in steps of 10%, to maximum of 70%.
Generate all images as black and white originals for black and white work, not monochromed colour images.
Material in Hebrew and Arabic script must be supplied in reverse page order.
Job make-up
Job must have a minimum of 3mm bleed.
Type and non-bleeding images such as logos, flashes etc, should be withdrawn 4mm from book trims.
Number of colours in digital data match Publishers orders.
Trim sizes are correct.
Spine size is correct for cover/jackets/cover for case.
Job has both trim and spine marks.
Data has been supplied as or PS.
Finishing Data (cover/jackets/cover for case)
Must supply a separate finishing file for each finish (e.g. spot UV and foil = 2 files).
Finishing data must be in one colour only and solid (e.g 100%K).
Finishing data must fit colour area exactly.
Supplying data checks
Correct number of files have been copied to CD (e.g. colour file and spot UV = 2 files).
Correct number of proofs supplied including finishing (e.g. colour file and spot UV = 2 proofs).
After writing CD please check that CD is then readable and contains the correct files.
View final data to check that all is OK.
or PS data has been copied to CD.
Pre-press guidelines - colour
Data suppliers colour rules
All digital data should be supplied in format:
Provide files in.
Ensure number of colours matches print order (i.e. The black text and tone are combined, not as separate colours).
Include colour proof from the file.
Embed all fonts.
Supply on CD/R, or via fto or email.
Postscript or file to contain high-resolution images.
Use logical file names.
Must supply separate printing, blocking and spot UV files.
Blocking and spot UV - one colour only please.
Must be a composite image.
Please supply trim and spine width marks.
Please don't use Adobe 3 or true type fonts.
Please don't leave errors uncorrected.
Please don't supply application files.
Please don't use lines less than 25 microns.
We can extract data from ftp sites.
Images must be supplied 'upright' so that files do not need rotation.
Pre-press guidelines - halftones
At Clays we use cold set web presses. Halftones can be successfully printed on text paper, however, wherever possible, halftones should be avoided in the first or last sections of the book (first 32 or last 32pp) as a certain amount of "set-off" (i.e. ink transferring onto the page facing the halftone) is inevitable due to the binding process. This will be particularly noticeable on hardback titles, if the illustration or tint is particularly dark or if the illustration is facing the title page or a blank page. If you have a title where positioning of halftones on these pages is unavoidable, please contact your account controller to discuss.
For printing on text paper the screen ruling should be 150 lines per inch. For printing as separate illustration sections printing on coated paper the screen ruling should be 175 lines per inch.
Please contact us for confirmation of the three curves required for halftone screening and for any other details.
Pre-press guidelines - reprints
Titles previously printed at Clays. Supply corrected pages on disc or via e-mail instead of camera ready copy.
Email files should be addressed to your account controller.
Correction pages must be supplied as single page files (e.g. cor-p123).
Pre-press guidelines - logical file names
It is important that files are named correctly. Please use the following styles when supplying data as we need to be able to identify the file from its name.
Text: Should have the page range or chapter in the name. E.g. prelims.pdf or I_X.pdf/chapter1.pdf/ 001-020.pdf
Endpapers: e.g. title-ends.pdf
Illustrations: e.g. title-illus01-16.pdf
Colour: E.g. title-jac.pdf/title-cov.pdf/title-cfc.pdf
Finishing data: e.g. title-foil.pdf/title-emb.pdf/title-spotuv.pdf
















