01 Mar 2010, 01:23
When I do full color magnetics, I print it first on the versacamm, laminate, then transfer to magnetic material. Recently however I have had a set come back to me that shrank. The vinyl shrunk causing the magnetic material to shrink also, leaving bubbles and just an awful looking sign. It took about 2 months for this to start happening. Does anyone know why this is happening and what I can do about it.
02 Mar 2010, 11:31
It's your vinyl shrinking-no matter what you do, you are using a cheap vinyl with high shrinkage rate and the lamination is pulling with it. I see this on 'full' color prints, because the ink shrinks as it dries and cures-causing a pull. You end up with 3 layers of vinyl-the cover of the magnet, (which you have no idea what type of vinyl it is) plus your printed vinyl and then your laminate. I do a lot of magnets with digital print now, and I use either Shinerite white (Fellers) or Oracal white with the gray backing-I use 3 different types of Oracal (3621 gloss or 3651), including the RA (rapid air release) and have not had any problems with it. The laminate is Oragrad 210G. Maybe thicker than most of you use, but I don't do any vehicle wraps and this thicker laminate hasn't failed me yet. Even for printing multicolor letters, laminate, then cut each letter-it has held up and no sign of shrinkage.
You need to match your vinyl to laminate- cast vinyl to cast laminate, calendered to calendered to get good success.
There are some printable vinyls that are known for years to shrink like crazy, Avery and Mactac are two of the worst.
Only thing I can recommend is change vinyls, and if you can get sample yards of several different types, print a full color image of a ruler at 100% so you have a guide to measure, along with some other designs, and do this on each sample, laminate, and stick it down to some magnetic material. Setup a galvanized steel 'sign' outside where vandals can't get to it, facing the sun...and put your magnets on there. Check them every month with your ruler and you'll soon spot which vinyls are shrinking. Throw out that vinyl and only buy the one that works for you!
02 Mar 2010, 11:33
I forgot another thing that works for me-if you can't let the printed vinyl sit overnite to 'cure' (and do anyshrinking from the ink) then go over it with a heat gun before laminating. This heat will 'set' the ink and help prevent shrinking Don't heat enough to bubble the ink or vinyl-just enough to get it warm to the touch.
Also, for full color prints, don't do a 'bleed' beyond the cut line. You need 1/4" of unprinted vinyl to also help prevent the shrinkage around the edges.