Duplexing and Potdevin efficiency

Hi guys,

I’m doing a lot more duplexing for business cards. I was getting way with spray mounting my 2 sheets. The second sheet was not printed and more for a color accent, so I could spray 2 parent sheets together then cut for the job.

I have a client with multiple employees that want front and back printed. Naturally, I would print both sheets separately and glue them together. But with printing 4 up for a 2000 card order, thats a lot of cards to glue. I can imagine that Potdevin would be cleaner than spraying, but I would still have to align everything by hand. Atleast this is what I’m observing on videos online. I’ve never seen one in action in person. Is there a more efficient way of doing this?


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Print both front and back on the same side of the sheet (work and turn) with a gutter between them. Score in the middle of the gutter, glue and then fold. If you scored accurately the sides will align perfectly. This will also reduce the number of formes / plates needed. I did this with my own business cards.

Michael Hurley
Titivilus Press
Memphis, TN

A perf that creates a square fold is handier for this, as a creased or scored edge will bulk up and not lie flat under whatever weights/clamp you use.

A cut score would work also

I would like to point out- in the least smart alec way possible- None of the above address assembling two pieces of different paperstock with increased efficiency using a glue, potdevin or otherwise.

Also the scoring method has the grain running the same way on both sides. We like to run the grain the opposite way on the second sheet, like on a sheet of plywood. I think duplexing is a lot like letterpress in general - inefficient.

Although, I am curious about Moo Cards and their “Quadplexing.” They must have some quick and precise way to do that.

Duplexing different paper stocks has its own problems. If the two layers are not of equal weight or absorbancy, they will curl as humidty changes.
Any experienced bookbinder knows this. If you want to laminate a thin sheet to board you must put an equivalent layer on the opposite side for balance. In the long run, warps occur otherwise.

Quadplexing is the (Grain direction) stacked crosswise (to prevent pull). On small stuff it ‘d not a huge problem but it get’s interesting around 5 x 7 inch.

RyanHowell, Moo prints digitally. I think they have the stock mounted large, cut down after, print digitally.

They must have some way to do it post-printing, though. They print on HP Indigo machines, which can only print up to about 18pt at most. They say the Luxe cards are 32pt.

Good point- In that case I have the sneaking suspicion that they probably just hire cheap labor and use hot glue potdevins/carefully line up against straight edges/over print the run to assure quantity.

If it were me I’d make a vacuum bed to hold one sheet down that carried glue, against some 3-point tabs that were at least 3-4 times the thickness of both sheets, and then lay the other one down/smooth out.

But in any case with duplexing you just lose a lot more- it’s quick indigo digital so printing 30 more sheets on a 60 sheet run only takes more time and a bit more ink and a bit more labor, but if you have an employee working for you who just does glueing then you’re set up.

These are all assumptions on my part, mind you.

I wonder what would happen if we applied the same cheap-labor sling-it-out approach to letterpress. Would that dull the artisan, hand-crafted appeal? Does anyone even care about that?

Letterpress has mainstream appeal these days, and with that, in our experience, has come a lot of price competition. Along with that, many people want solid reverse backgrounds, thick paper and printing on both sides. I’ve been trying to figure out just what to do about that, and I haven’t figured it out yet. I do know that running the slow, old Potdevin myself is surely not the solution.

Set up a two sided tray (rather like a jogger tray) the size of the sheets you want to work with. With two people (ideally) have one person running stock through the Potdevin while the other lays in the other stock into the “corner” of the tray. If you using a glue with some positionability, you should be able to lay up a square stack.

Ideally you would roll out each set to avoid getting bubbles into stock and then get the sets under a book press (or equivalent) as soon as possible). If you are doing very large quantities, you may want to get a set of squeeze rollers to press the sheets together after you get the initial glue position.