One major difference between the various types of Oracal vinyl is the adhesive strength. It determines what type – 631, 651, 751, and 951 – you should use for your crafting project. Oracal 651 has a clear, solvent-based adhesive that the company describes as permanent, making it good for outdoor applications. But will it stay there forever if you stick it to a surface?
Is 651 A Permanent Vinyl?
Oracal calls the stronger glue on 651 vinyl “permanent,” and it can stick to uneven surfaces and stand up to any type of weather. Despite the name though, 651 isn’t permanent – it’s just stronger and harder to remove than Oracal 631 vinyl. It is also thinner, allowing it more flexibility and conformity to surfaces. Almost all Oracal 651 colours will last outdoors for six years or longer (though some options, like metallic colours, might last a shorter time).
When Is Oracal 651 Appropriate?
Oracal 651 is often called outdoor or sign vinyl because it is popularly used for outdoor signs. It is a strong enough adhesive to survive all outdoor weather conditions. It is waterproof, making it great for any project that you will wash or have exposed to the rain, like coffee mugs and work vehicles.
While you can use 651 for interior surfaces, it’s not ideal. Getting the tough adhesive off your walls can cause damage. 631 is the ideal vinyl for any project that you need to remove easily without damaging the surface underneath. But if you’re having trouble getting the 631 to stick to a surface like unfinished wood, try switching to the 651. The stronger glue works better on surfaces that aren’t perfectly smooth and flat.
Oracal 651 even works for custom boat decals! Some people might find themselves confused by this, but it’s a good way of illustrating the usefulness of all Oracal’s vinyl. Crafters sometimes call Oracal 751 and 951 cast vinyl “marine grade” because they work better over contoured shapes and can wrap large areas like boat hulls. Cast vinyl starts as a liquid that the manufacturer pours into a flat casting sheet to make a thin vinyl. The thinness and flexibility of the material allow 751 and 951 to stick to a wide variety of surfaces longer than 651.
But 651 applied to a boat isn’t going to fall off when it hits the water, just like how 631 isn’t going to fall off an outdoor sign after a week. It won’t last as long as 751 on a boat, but it’s still useful. Every Oracal vinyl is incredibly durable, but crafters will find that some are more durable than others. The key is to know which one is best for your specific project. Whichever one you choose, they are all compatible with most die-cutting machines, including Cricut and Silhouette!