Need Help Suction cup marks on material

[MGB_LE]

We have had an ongoing problem with fresh boards of Sintra, expanded PVC, PALIGHT, arriving with invsible suction cup marks that reveal themsevles when printed over. We can't see them before printing, but they ruin the print. We can flood print white underneath to hide them, at the expense of slower printing and higher ink cost.
Surely we're not alone in this. What feedback does the group have around this issue?

 

[MGB_LE]

Here are examples of other deliveries of board with similar issues. These look like suction cups used to move the boards around or stack them on pallets.

 

[Kripted]

Have you tried wiping it down with Isopropyl before printing?

 

[DL Signs]

Make sure you let your vendor know there's an issue too, see if they'll correct it.

 

[MGB_LE]

Have you tried wiping it down with Isopropyl before printing?

Yes, we have wiped the board before printing, and still seen the defect.

 

[MGB_LE]

Make sure you let your vendor know there's an issue too, see if they'll correct it.

The vendor has replaced the material each time this has happened. We just hate the wasted time and ink.

 

[MrDav3C]

Is it worth seeing if this disappears on its own over 24hrs or with heat?

 

[MGB_LE]

Is it worth seeing if this disappears on its own over 24hrs or with heat?

It does not disappear. The samples I used in my photos were weeks old examples.

 

[DL Signs]

Went through this before I retired. We ordered 10+ pallets of sintra at a clip, and had so many problems with marks, scuffs, and other contamination issues. We went through countless suppliers, and finally found one that supplied us with stuff so good that we could just unseal a pallet and it could go straight to print. Don't remember where we finally got it from (I know one supplier was 3A composites, might be the one), but there's good stuff out there. Maybe start looking for at different suppliers and manufacturers, because you sure can't make money like that. When you contact them, let them know what problems you're dealing with.

 

[MGB_LE]

Went through this before I retired. We ordered 10+ pallets of sintra at a clip, and had so many problems with marks, scuffs, and other contamination issues. We went through countless suppliers, and finally found one that supplied us with stuff so good that we could just unseal a pallet and it could go straight to print. Don't remember where we finally got it from (I know one supplier was 3A composites, might be the one), but there's good stuff out there. Maybe start looking for at different suppliers and manufacturers, because you sure can't make money like that. When you contact them, let them know what problems you're dealing with.

That's really useful. I will look into them.

 

[Humble PM]

3A - you pay a premium, but I don't think I've had a bad product from them in over a decade (and I've occasionally bought cheap, and paid the price).