Need Help General Misery with Backlit

[4cpro]

So I just finished this project which on the surface looks like a great project. It's bigger than we typically get but I was happy to get it and was pretty aggressive on the numbers.

Specs:
Quantity: 1350 / 850
8.25" x 28.75"
Contour cut to shape (one edge angled)
Printer: HP 360 Latex
Material: Sihl Vivalux and Diversified Display House Branded

So I printed these panels 24 up (6 across / 4 tall) and cut them to size on my Colex Flatbed. These panels needed to be exact size which I was unaware (nor did I think they would not be). It turns out after printing and cutting all of these, the panels were a little over 1/16" short. There is no frame around these so there was a slight light leak and the entire job was rejected (Insert Misery Title Here). My 1 up sample was perfect. I would have expected if anything the material to stretch longer. It seems that for every 10 feet I ran, it shrank about 1/2".

So I have a million questions pertaining to this job because it turned out to be a nightmare for me. But... thousands of dollars later, it gave me some insight into little details that usually wouldn't matter.

I spoke to Colex who told me the cutter will adjust for stretch based on the position of the registration marks. Well, this makes sense and would explain why every panel was short. Again for a typical print who cares. I expressed by unhappiness with this and they told me I could force the Colex to cut the the exact size and ignore the stretch. This actually worked but then all my panels were cutting crooked and out of center.

My first questions are:
Is this normal?
Would I have been better off running these horizontally, not vertically?
Is there a better material for this that doesn't stretch/contract or is this heat related to Latex?
I ran some with and some without the takeup reel/dancer bar. All seemed to be the same. Does the takeup reel cause more deformity?

So I have other questions but will start here.

The entire project was:
480 run on Sihl Vivalux (rejected by me because we were sent two different lots of material and color was way different on the first two rolls we ran)
1350 pieces run on Sihl Vivalux (rejected by client)
1350 pieces run on Diversified House Brand (accepted but we had issues cutting to size and straight)
850 pieces (second job) run on Diversified House Brand (still issuescutting to size and/or straight)

Needless to say it was a nightmare. After the first job was rejected, we couldn't get any more Sihl Product so had to find someone local that had like 12 rolls on hand. So I just delivered the last of the second job and now need time to reevaluate everything that went wrong (there were alot of things). I ended up printing the reprint 12 up but still had issues.

Thanks for any info. I really need this info to determine if I'm running the right machines, materials etc. As lousy as this job was, the client was happy I made it right and stood behind my product (and stayed here all night running the reprints). Longer runs seem to be getting more common and looking for a machine that is fast and has good quality. Up until this project I've been pretty happy with the HP 360 although the color is questionable at times.

 

[CanuckSigns]

I seem to remember quite a few threads on here about issues with the latex machine printing inconsistent panel sizes due to the heat causing the vinyl to shrink/expand. My guess is that is the case here, when you printed a one off sample, the stretch was insignificant, but as you started running larger runs the compounding effect took over and you ended up with this.

Someone who knows more about the latex machines can chime in with a possible fix or work around.

When you were cutting these out, did they get progressively worse as they went on, or were they consistently off?

 

[Bly]

HP latex will never print consistent lengths. If we have to print on our 360s and have an exact length we print longer using the
scale adjust setting in onyx, then make sure we cut the job on the Zund at 1:1 which reads the marks then will cut exactly the size in the file.

 

[Christian @ Visual Graphx]

How were these used in the final application? Are they slip in or adhesive applied?

Sounds like you need to run less tension on your take up reel and vertical compensation to get the print length closer, also you need to look at possibly adding more cutter dots in between pieces to have more data points for the cutter to compensate better, unless your cutter is cutting even inset on the bleed?

 

[4cpro]

How were these used in the final application? Are they slip in or adhesive applied?

Sounds like you need to run less tension on your take up reel and vertical compensation to get the print length closer, also you need to look at possibly adding more cutter dots in between pieces to have more data points for the cutter to compensate better, unless your cutter is cutting even inset on the bleed?

MY guys at Colex told me to add dots in between the prints as well. I will try that. My issue with 1:1 cutting is the cut was actually not parallel to the print. Almost like one size was stretched more than the other. I tried running prints with and without the take up.

In reality, I'm a business owner who spends more time selling than I do producing. 10 years ago I was Mr. Production but those days are gone. In the the past two weeks each one of my graphics people took a week vacation so I jumped in on the wide format projects to relieve some pressure. I have two graphics people dealing with files and another person running Latex, flatbed and cutter yet no one has seen any of the color, material or cutting problems before? Why do I find all these issues out in a few days.

Material - I was very hands on this job and realized there are issues with our "house" backlit and there are better and more economical options.

Software - Onyx issues which is lack of training (or lack of wanting to know more). I was asking a bunch of questions and couldn't get a straight answer such as... Why does this PDF process on two different computers through Onyx and the color is completely different?

Machinery - Why am I the one to question and find out all these issues in the middle of one project. Has anyone else had a problem with any of this in the last 5 years? Does anyone else have issues with our Colex not cutting evenly across the bed? Does anyone notice that our Duratrans scratches... and so does our gray backed PVC?

So in the end, it's my fault for not managing this. Unfortunately in the heat of battle, sometimes we take the easiest route to get the job done, not the correct route which is asking questions and solving the problem. I just wish my people wanted to know the answer, just because they were curious about their profession, color, materials and possibilities... just because.

I'm going to start looking at a second machine and it sound like the HP Latex isn't the problem, it's a training problem. Being busy is good but its a poor excuse not to do things right.

 

[4cpro]

How were these used in the final application? Are they slip in or adhesive applied?

I have no clue.. I'm actually a sub for a much larger company who is selling them to a display company. This was one part of a much larger project. I do know it will be coming in again so I want to address the issues now. As bad as it was, the client was very happy we made everything right and went the extra 10 miles.

 

[Terrance the Deuce]

Software - Onyx issues which is lack of training (or lack of wanting to know more). I was asking a bunch of questions and couldn't get a straight answer such as... Why does this PDF process on two different computers through Onyx and the color is completely different?

Meaning you have onyx on two computers (thrive?) and are getting different color results from the same printer?

 

[4cpro]

Meaning you have onyx on two computers (thrive?) and are getting different color results from the same printer?

Yes. I can import the same PDF of two different computers and process and get two completely different color. One is correct, the other results are way off. I haven't looked into it yet since we've been dealing with this past project but. I ran some 3M Material that printed light blue on on one machine and a perfect gray on the other. The gray is what I needed but couldn't figure out why the color was so off. Luckily I jumped on the other system and re ripped the same file and its correct. Same File, Same Rip, two different desktops.

 

[Terrance the Deuce]

Yes. I can import the same PDF of two different computers and process and get two completely different color. One is correct, the other results are way off. I haven't looked into it yet since we've been dealing with this past project but. I ran some 3M Material that printed light blue on on one machine and a perfect gray on the other. The gray is what I needed but couldn't figure out why the color was so off. Luckily I jumped on the other system and re ripped the same file and its correct. Same File, Same Rip, two different desktops.

I'm assuming you are using the same profile on both computers and all the same settings. If so, try recalibrating the profile on your main computer. Export the profile and import it to the other computer. Your results should match.