Had another thought about the problem you are having, (there’s always more than one way of looking at things in this game) and have thought of a couple of other ways the problem could be solved.1/ A frisket bar could be used to steady the sheet. This is a bar that is affixed between the platenand type/block. It steadies the sheet as it comes down into the lays for printing. It is usually a vertical bar with a “T” fixture that can be taped into position to get as near as possible to the image area causing the problem. This is commonly used to alleviate slurring problems that occur when a sheets remains “stuck” to the block or type matter. Most Heidelberg machines have a bar under the chase area specifically for this purpose. On hand fed C&P’s however I’m not sure this feature is available.2/ Type-high solid bars (block or 1em leads) can be run outside of the trim area on the job to assist in spreading the ink and provide support when the inking rollers come over the image area.Hope this helps, but please note some of these ideas are from a different era and may/may not be applicable to what you are doing today.

Have you considered running your solid colour on letterpress? To do this without showing impression you could print the solid from a wood or metal- based plate (.918 thous high from memory) leaving plenty of bleed around the edges so that the heavy edge of the blockprint is later trimmed off. The rest of the solid would then have no discernable pressure mark and (dare I say it) probably produce a stonger print than offset (thus matching your front side print).To print a solid on a letterpress platen machine can be tricky because the forme/inking rollers don’t really have adequate coverage for the amount of ink required. To get around this problem you can “double roll” the ink rollers to build up extra ink. The action of double rolling I’ll have to explain based on an automatic press but similar principle would apply with a hand-fed machine. On an automatic- platen type- machine your first sheet passes into the lays, the impression handle is pulled on and the print is taken. The minute the platen goes on impression for the first print the suction air on the feeder is turned off stopping the second sheet from going through to the lays. Then the Impression handle is thrown off as the first sheet goes to the delivery. Whilst suction and impression are off, the inking rollers return to the ink distributing drum for a second hit of ink thus producing twice the amount of ink as normal. It takes a bit of practice to get into the rythym of pushing buttons and pulling handles and if its a long print run you’ll swear your arms have ended up longer than they used to be but the print result can be well worth it. Because a lot of ink is being carried on the paper it is advisable to add either a paste drier or cobalt drier (depending on texture of paper/board) to your ink. It would be advisable to run sheets into the delivery in small piles using an anti set off powder to stop sheets marking each other or if no powder available rack the job out in single sheets on a drying rack/or bench.

If your machine is a clam shell platen; packing usually consists of one piece of card (about business card thickness) taped to the platen surface, 2/3 sheets of newsprint, or something of a similar thickness, another sheet of card then an oiled- manila top sheet. The card affixed to the platen is designed to ensure that when you spike two holes through from the top sheet, ( to position your make ready) there is no movement.These packing densities are based on a Heidelberg automatic platen and may differ for your machine but the basic principle should be similar. As Cleanwash mentions starting light with the filler sheets and building up to the required thickness is a good way to go. As you adjust your packing you will notice by looking at the back of the paper (holding it up to the light gives a clearer picture) that the impression may be uneven. If heavier at the top the platen is usually over packed if heavier at the bottom it’s under packed. The trick then is to balance the packing in tandem with the impression lever (if your machine has one) to get a perfectly level overall impression. Once even you can then patch up any lower areas with a make ready .Hope this helps. If you need any assistance with make ready please don’t hesitate to ask.

Looking at your pics it could be to much impression overall. Ideally the impression should be just kissing the paper not squeezing to heavily into it. Maybe a fresh packing and less pressure might solve the problem.Ink may also be an issue. There used to be (I’m going back quite a few years here) an ink called G Man which was very stiff and less prone to ghosting and bleeding on edges. As to what an equivalent would be called now I really wouldn’t know but it used to be used in label printing a bit so someone in that side of the industry may be able to help.

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