Double Sided Lawn Sign Printing on FB700

It's coroplast... They are never cut square. Print the first side, cut, then load individually.

 

Coroplast is normally 96 1/2” long, cut the 1/2" then your sheet will be square.

 

Need to make sure you have square material. We print double sided on Matraplast without any issues.

 

I'm not sure about the HP user interface. When we print a 4x8 sheet, we flip and move over the starting point to the amount that is shown from the first print for the white space (.125 to .225"). This works very well for us. Does the HP user interface allow you to adjust the starting point for the top/back and left/right on the starting point for the print?

If Harbor Sales is in your area then you can purchase square sheets from them.

 

I'm running some full sheet 18"x24"s right now and this is how we do it.

We create two 48"x96" files in Illustrator (or whatever layout program you use) They each have 10 of the panels copied and pasted on them accurately butted up to each other.

SIDE A file has a .25 point light grey stroke/cutline around the 18"x24" perimeter of the signs. SIDE B has NO stroke color applied to the boxes.

Lay your coroplast on the table with a little hanging out past your origin point. Print, pull off table, trim only that front edge to square your material, flip it over, align the newly squared corner on your origin point and print SIDE B.

Boom!

 

You can usually order square cut coro for maybe $1 more/sheet. The amount of trouble it saves attempting other methods is worth it.

 

Square up the material

 

Having the same exact issue. I am bringing in some square cut material to see what kind of difference that makes.

 

Are you running full sheets with 10 signs ganged up together?

If so, a 4'x8' is usually almost an inch or more longer than 96". Just place the front edge of the sheet past your origin point of the print, print your first side, then trim that edge square. Flip the whole panel over, align that squared corner and then print the second side.

Should be pretty close if you trimmed carefully.

 

There's a lot of good ways to do it already mentioned. But what I do is this...

- set it to print centered on the sheet (on the printer not the RIP)
- set it to measure every load, using the "minimal" setting. Minimal will only measure the leading width and find the starting edge, which is what you want in this case.
- print the first side and eject to input side
- flip the sheet over in such a way that you are using the same leading edge of the coroplast....this step is the key. Because it's centering based on the measurement it took from the leading edge, and since you are using the same leading edge it will center in the same location for the back side (I dare say almost perfectly in my experience)
- print the back side, keeping in mind you will need a second print file exactly the same as the first but with the signs rotated 180 degrees.

I actually developed this method for printing 2 sided PVC with a large amount of small units (full bleed with borders in the design) ganged up on a 4' x 8' that will then be cut on a CNC router but later found it great for yard signs. The reason it works is because it's centering to the same leading edge on both sides of the coroplast and not measuring for skew. This way the left/right/trailing edge can be skewed all they want, and the sheet can be of varying widths/lengths from sheet to sheet (typically they are closer to 97", sometimes over 48" and never square or consistent) because all loading/centering is done based on the same leading edge. The biggest disadvantage to this method is it requires and extra cut during trimming because it's now leaving roughly 3" on the left/right instead of 6" on one end. But it will line them up nicely and if that's what it takes for a successful print then one extra trim is no big deal. I like this method because it's basically fail safe once it's set up properly. I've tried buying "square" sheets for an additional cost and they are more square but not square enough to accurately line up bordered, full bleed prints from front to back on a full sheet . Hope it helps!

 

I always wondered this for the FB.
Is it faster to print double sided 4x8 sheet of coro (10 - 18x24) then cut
or feed in (10) 18x24 precut sheets?

 

Also just took a second look at your picture....you can also flip every other sign with a design like that. So that the pink on the bottom buttes up to the pink on the bottom of the next sign, then the white on top of that sign buttes with the white on the top of the next sign and so on. Making it so that it's pink to pink and white to white, making subtle misalignments null during trimming.

 

Full sheets all day long, then trim them in between print loads. Using production speed, 600 x 300 I can output 400 finished signs a day (comparable to "express" mode on newer models). Same job using precut sheets is about 300 a day or a little more, if you have a good operator who doesn't leave a lot of lag between loads. Not to mention if using pre cut sheets and full bleed designs you are going to have a whole lot of ink on the belt to clean up. The biggest time saver on either method is setting it to measure only the first load if you can get away with it i.e. well designed signs that don't require tight tolerances. But if you have to measure every load then you are losing a ton of time with N-UP printing pre cuts.