digital prints and shrinkage

[gabagoo]

I went to see a manufacturing plant that I do a lot of interior signage for. As I walked through the plant to look at this new project I passed by many of the signs I have made. usually info signs yellow and white backgrounds with black copy on 1/8" pvc. To my dismay I was sort of taken back by the amount of shrinkage I see along the edges. I would say about 1/16" inch of white was around each edge. before digital we used vinyl cut and assembly but never remembered seeing shrinkage anything like that.

So, although no one is complaining about it...well I hope not anyways..... Where do I go from here in regards to this shrinkage. Pretty much all digital 3mls I have used do shrink... I need to be competitive and can't see going to cast as that means also going to cast laminate which is going to bring the cost up significantly. I suppose I can ask the client which way to quote it, but in most cases they don't need more info to add to their already stressful lives and that could mean they move to another supplier who does not ask those types of questions and just gives them 3ml anyhow.

How do others here approach this matter?

 

[MikeD]

I've been reading about calendared films lately, and specifically this issue. One thing I've read is that different plasticizers play a role in shrinkage; polymeric plasticizers are more stable than monomeric plasticizers. I picture it like burying a string in the mud- it can be pulled out easily. Then bury a tree with lots of branches in the mud- it doesn't come out so easily. I think that's a good analogy for describing monomers and polymers.
A calendared film with polymeric plasticizers will have more dimensional stability than a regular calendared film, and will not cost as much as a cast film, but will be a little more than regular old calendared film.
Calendared films with polymeric plasticizers are usually called by names like "High Performance Calendared."
Good Luck!
MikeD

 

[gabagoo]

I've been reading about calendared films lately, and specifically this issue. One thing I've read is that different plasticizers play a role in shrinkage; polymeric plasticizers are more stable than monomeric plasticizers. I picture it like burying a string in the mud- it can be pulled out easily. Then bury a tree with lots of branches in the mud- it doesn't come out so easily. I think that's a good analogy for describing monomers and polymers.
A calendared film with polymeric plasticizers will have more dimensional stability than a regular calendared film, and will not cost as much as a cast film, but will be a little more than regular old calendared film.
Calendared films with polymeric plasticizers are usually called by names like "High Performance Calendared."
Good Luck!
MikeD

so let me ask you...for interior signage, what do you use knowing that the 3ml will shrink away from the edges revealing the substrate. I personally think in most cases it is no big deal as no one is looking for it that way...but I suppose on a receptionary display or something that is possibly wayfinding it could be an issue over time

 

[Gino]

You'll either need to leave a border or put some edge capping over it. It all shrinks, including the cast. Maybe not as much, but for the cost difference, it shouldn't.

Remember all the threads and discussions about outgassing, laminating too soon or too long after the print comes out...... ?? No matter what binder your machine uses, the inks have to penetrate the vinyl to a certain degree and when they are heated up, they eventually start..... or at least try to return to some of their original shape and size.... then add on top the natural sequence of vinyl shrinkage, especially when inks are introduced, regardless or water-based or solvent, they have some bearing on what will happen over the next year or two to your vinyl adhesion. Anything that dries or cures.... shrinks.

One of the two reasons we moved into flatbed printing. Absolutely no shrinkage. Even George Costanza can't say anything about it.

 

[Mosh]

I do lots of safety signs, I always put a white boarder on them just for this reason, even yellow caution signs. Nature of the beast, but after doing it this way for 8 years (used to cut vinyl or screen), not had anyone complain.

 

[Jester1167]

Calendared vinyl starts its life as a big ball and gets rolled between multiple rollers. The space between the rollers gets smaller and smaller until it gets to the desired thickness, then they add the adhesive and liner. It's natural state is that big ball and it want to shrink back. If you have a few odd colors of calendared vinyl that have been around for years, look at how much it has shrunk on the liner. I have seen the really cheap stuff shrink as much a 3/32" on a 15" roll...

Cast vinyl is sprayed on a webbing in a liquid state and cools, then they add the adhesive and liner. Good cast vinyl will shrink so little that you will only notice it during removal. You will see a little hairline of dirt and adhesive around the edges after removal.

Coroplast and PVC are low energy products and are probably compounding the issue. For long term signs we always used cast vinyl. If money is an issue and calendared has to be used, you can incorporate the sign blank color as a border in the design. The thicker the border the faster you can install them because you don't have to be as tight with your registration. You will still end up with the adhesive dirt ring around the graphic though.

 

[MikeD]

I'm not sure exactly what to recommend. For our "signage" type products, it's not really a concern for me because they are all short term.
I was looking into different films and shrinkage while trying to learn about wrap films and ended up using cast, but I have some test parts applied in the real world (we used our own cars that we drive everyday,) with various film combos for partial wraps using different grade calendared films with various laminates ranging through regular calendared, "high performance calendared" and cast. I know some of the parts will eventually fail, but the experiment will give me real world answers in regard to compatibility and durability.

I can say that I have a decal that was printed on an unknown calendared film and laminated with an unknown cast laminate that I made about ten yrs ago and the vinyl shrank and the laminate did not. There is a clear border of laminate around the cut of the decal. It was applied to a painted metal door.

I know you don't want to laminate or use cast. Wish I could be more helpful!

 

[TyrantDesigner]

Few years ago I had to do a lot of interior mall signage. About the only thing that seemed to stop the shrinkage of calendared prints was sealing the edge with paint (was doing a lot of gatorfoam at the time so edge painting was essential) for pvc ... I have no idea. You could technically use any sort of edge sealer for wraps and it should prevent the pulling from the edge for a while ... but that stuff is kind of rubbery so it wouldn't last long before tension ripped the sealer and the gap would show. otherwise, the issue comes to using cast vs calendered which you already described. ... since it's pvc ... one option is making sure the substrate and the edge of the print are the same color so it visually doesn't look like it is an issue. other than that I would just set proper expectations and hope for the best.

 

[Mosh]

I never have curling problems, just a little 1/16" of the PVC shows after a year or two. Using cast helps, but cal keep the costs down and work fine for indoor. Like I say, never had a complaint after 1,000's of signs.

 

[ddarlak]

i have done this many times and it looks great.

over print the image by an inch all around.

cut the corners strategically so it folds perfect and fold over the flap to the back of the substrate.

it gives a great edge look and you don't have to worry about shrinkage.

 

[Biker Scout]

Cost of the cast vinyl should be an insignificant part of the overall price of the sign. Especially if you want to keep this customer happy, and still make the sale.

Let's say you both agree on a price per sign, say $50, if you are installing 20 signs in his facility. Let's call the sign dimensions 12" x 6" for the sake of the example. That would take 2 signs to equal 1 sq. ft.

A decent quality air release (calendared) vinyl can be had here through one of the forum's merchant members. We'll use theirs for the example.

.19¢ per sq. ft. for the vinyl, and .14¢ for their lamination = .33¢ per sq. ft. (16.5¢ per sign)

You mentioned PVC... OK, I like black for mounted signs. One 4x8 Black Komatex is about $35. What's that about $1.10 sq. ft. We can get 64 of those signs per board, (.55¢ per sign)

I never heard of ink costing more than .25¢ per sq. ft., so let's use that. (12.5¢ per sign)

What are we at? .84¢ in materials cost. Now let's add production/shop overhead. Shouldn't take more than an hour to make these signs if you're set-up properly. But let's add 2 hours. I'm guessing a decent in-shop rate would be about $30 per hour to cover insurance, utilities, labor etc... that comes out to $1.20, that brings us up to $2.04 per sign. (I way over estimated the cost of ink per sq. ft., so let's just call it an even $2)

Now, let's talk about upgrading to a brand name cast material with super aggressive adhesive: OraJet 3951HT (High tack for low energy surfaces like plastics) $1.26 per sq. ft. laminated with OraGuard 290 at .68¢ per sq. ft. ($1.94 per sq. ft. or .97¢ per sign)

Now if we go back to our example sign on calendared, it was going to cost us $2.00 per sign, leaving $48 profit for the shop. If we upgrade (to keep customer happy, give us peace of mind) then we are only adding .81¢ to the cost of the sign over what we were initially charging. That still leaves us with $47 profit per sign. All without having to increase the cost of the sign to your client.

How is it that you are not going to make any money by offering a superior product? Are you so close to your margins that your business model dictates giving away your work just to keep busy? Or is it just greed and not serving your client's best interests?

 

[gabagoo]

Cost of the cast vinyl should be an insignificant part of the overall price of the sign. Especially if you want to keep this customer happy, and still make the sale.

Let's say you both agree on a price per sign, say $50, if you are installing 20 signs in his facility. Let's call the sign dimensions 12" x 6" for the sake of the example. That would take 2 signs to equal 1 sq. ft.

A decent quality air release (calendared) vinyl can be had here through one of the forum's merchant members. We'll use theirs for the example.

.19¢ per sq. ft. for the vinyl, and .14¢ for their lamination = .33¢ per sq. ft. (16.5¢ per sign)

You mentioned PVC... OK, I like black for mounted signs. One 4x8 Black Komatex is about $35. What's that about $1.10 sq. ft. We can get 64 of those signs per board, (.55¢ per sign)

I never heard of ink costing more than .25¢ per sq. ft., so let's use that. (12.5¢ per sign)

What are we at? .84¢ in materials cost. Now let's add production/shop overhead. Shouldn't take more than an hour to make these signs if you're set-up properly. But let's add 2 hours. I'm guessing a decent in-shop rate would be about $30 per hour to cover insurance, utilities, labor etc... that comes out to $1.20, that brings us up to $2.04 per sign. (I way over estimated the cost of ink per sq. ft., so let's just call it an even $2)

Now, let's talk about upgrading to a brand name cast material with super aggressive adhesive: OraJet 3951HT (High tack for low energy surfaces like plastics) $1.26 per sq. ft. laminated with OraGuard 290 at .68¢ per sq. ft. ($1.94 per sq. ft. or .97¢ per sign)

Now if we go back to our example sign on calendared, it was going to cost us $2.00 per sign, leaving $48 profit for the shop. If we upgrade (to keep customer happy, give us peace of mind) then we are only adding .81¢ to the cost of the sign over what we were initially charging. That still leaves us with $47 profit per sign. All without having to increase the cost of the sign to your client.

How is it that you are not going to make any money by offering a superior product? Are you so close to your margins that your business model dictates giving away your work just to keep busy? Or is it just greed and not serving your client's best interests?

I did the math on using cast over the calendered and the material cost is about double...Now it is true that to do this will result in better quality signs and I may just try it out and see. I also like Mosh's idea of leaving a white reveal around the edges...

 

[Biker Scout]

By my example above, it's clearly more than double the cost...(like 3X) but remember, it's only one component. Double the material costs does not equal double the sign cost.

Yes, the better way to make the sign is to leave 1/8" to 1/4" border around the print, showing colored substrate. BUT laminate the whole sign, not just the print portion. Polycarb would be my first choice going into a manufacturing facility.

 

[Biker Scout]

One thing I should point out is that small shops without a lot of inventory on hand face this problem every day. They can't outright afford $2000 worth of materials just to get a roll of cast laminate and vinyl. So they see the cost of the materials vs. how much potential job will yield, and end up printing on whatever they already have in the shop and use most often. Sometimes, people try and roll the cost of the materials into the price of the job. The reality is that it's not the customer's burden to shoulder the cost of the entire roll of vinyl for $1000 sign order. Either get a business credit card, or just suck it up and get out there more and push your business. Even if you only made $940 on this job, you still have 620 sq. ft. of premium materials on hand for the next job. Eventually, it's free material and you can add the cost of the materials into your profit side. It's called the cost of doing business.

 

[gabagoo]

One thing I should point out is that small shops without a lot of inventory on hand face this problem every day. They can't outright afford $2000 worth of materials just to get a roll of cast laminate and vinyl. So they see the cost of the materials vs. how much potential job will yield, and end up printing on whatever they already have in the shop and use most often. Sometimes, people try and roll the cost of the materials into the price of the job. The reality is that it's not the customer's burden to shoulder the cost of the entire roll of vinyl for $1000 sign order. Either get a business credit card, or just suck it up and get out there more and push your business. Even if you only made $940 on this job, you still have 620 sq. ft. of premium materials on hand for the next job. Eventually, it's free material and you can add the cost of the materials into your profit side. It's called the cost of doing business.

I am not sure who you are directing this statement too. I may be a small shop, but I always keep a lot of stock on hand for anything I may need it for. I just wonder what the hell calendered vinyl is good for anymore lol

 

[Biker Scout]

It's obviously not directed to you specifically, because I've never been to your shop. But I have had to broker out jobs many times when my printer was down or whatever, and I see this very often. Some shops don't want to print on what I have spec'd out (for my clients) because the rolls of material are too expensive and they don't stock it. Optically clear lamination comes to mind... really pisses me off when shops offer window perf, but don't have an inch of optically clear to save their lives.

Anyway, I agree... If there is a better alternative out there, I like using it. I consider calendared to be for short term usage. (even if the manufacturer claims a 6 year outdoor life)

 

[Gino]

I am not sure who you are directing this statement too. I may be a small shop, but I always keep a lot of stock on hand for anything I may need it for. I just wonder what the hell calendered vinyl is good for anymore lol

We use VERY little of it at all anymore. It's far cheaper for us to produce a sign flatbed printed, even it's only one color.

Guy/girl wants a 2' x 3' 2-sided Cor-X, plywood, aluminum, whatever kinda sign. Once the artwork is decided, it takes a minute or two to send it to the rip, another minute to rip and now it's ready to print. 2x3 will take 10 minutes or so to print both sides. Gang it in while you're doing a similar substrate and you've just cut out the cost of vinyl, cutting time, weeding time, application tape, measuring, applying and cleaning off any guidelines..... for two sides..... not to mention it drooping over and touching itself and having to cut another one. Sheesh, it's really a no brainer, once you have the right tools..... or just sub it out.

 

[Ditchmiester]

This intruiges me as well. What other Cast Vinyl would be recommended besides 3951HT? Do any other companies make a high tack cast vinyl?

 

[Biker Scout]

There are a couple of different brands that offer "low energy substrate" aggressive adhesive. I just went with the most expensive I could find for the sake of illustrating that the cost of the vinyl shouldn't really matter. It's the end use and customer satisfaction that should be the ultimate end goal.

I believe 3M, Convex, Arlon, Avery and possibly some off brands like general formulation and briteline have something they would consider being appropriate for plastics, like PVC. Just refer to their material usage matrix, that most offer either in their catalog or online.

 

[gabagoo]

We use VERY little of it at all anymore. It's far cheaper for us to produce a sign flatbed printed, even it's only one color.

Guy/girl wants a 2' x 3' 2-sided Cor-X, plywood, aluminum, whatever kinda sign. Once the artwork is decided, it takes a minute or two to send it to the rip, another minute to rip and now it's ready to print. 2x3 will take 10 minutes or so to print both sides. Gang it in while you're doing a similar substrate and you've just cut out the cost of vinyl, cutting time, weeding time, application tape, measuring, applying and cleaning off any guidelines..... for two sides..... not to mention it drooping over and touching itself and having to cut another one. Sheesh, it's really a no brainer, once you have the right tools..... or just sub it out.

I have access to a flatbed printer and the pricing is very reasonable...however, I don't want my business going to the point where I am reduced to being a sign broker. I don't mean to insult anyone who is one...more power to you.
I realized years ago, before I owned a digital printer that I had little to no control on how things were being printed...ie. Resolution, colour control etc.... Possibly in the future we will all have flatbeds as we all seem to have printers and vinyl cutters...but until that day I really need to keep production more or less inhouse.