Does vinyl have a grain or am I mad?

[Robert Lambie]

Unless a purposely created texture film, then no there isn’t a grain as such.
I guess it could be argued that some vinyls like calendered vinyl may have a sort of micro mottling ( made-up description ) on the surface in the direction it is compressed by the rollers but as i say, "not a grain as we know it captain!".

some vinyls do weed better than others though, various things come into play there though… but the trick is down to a clean sharp blade and the correct pressure. if very small text then perhaps cut in tangental mode if available. Always weed top right corner coming at an angle to the bottom left. This is because more letters are open towards the right allowing the vinyl to separate / weed itself easier without lifting leading edges of the vinyl.

[Simon Worrall]

Some air release vinyls have the channels going in one direction in the glue.
Spose this might affect the weeding, although I have never noticed it.

[David Rogers]

quote Robert Lambie:

… Always weed top right corner coming at an angle to the bottom left. This is because more letters are open towards the right allowing the vinyl to separate / weed itself easier without lifting leading edges of the vinyl.

Numbers on the other hand I’ve found tend to weed better from the left as there are more of the ‘problem’ areas on the left…turn your sheet upside down and weed from the right (right handed person).

Back to the ‘grain’ thing, some vinyls do tend to tear cleanly from a sharp corner when weeding – I notice it mainly on metallic callendared vinyl and mirrored gold polyester films. Not a grain as such but it’ll be tearing in the direction you’re weeding combined with the way the material was extruded / rolled out.

Dave

[Phill Fenton]

In cold conditions vinyl becomes very brittle and much more prone to tearing. Particularly if it’s a cast vinyl

[Gordon Smithard]

Thanks for the replies. I use normal polymeric stuff from Spandex (image perfect 5700).
Interesting to read Roberts answer about weeding from top right to bottom left, I’ll try that next time, I usually weed from bottom right to top left for no particular reason.

[George Neagu]

quote Gordon Smithard:

Stupid question but does vinyl have a sort of grain? Reason for the question is that I do a lot of very small fiddly stuff for stencils and when weeding I get better results if I turn the vinyl on it’s side, or sometimes upside down, it’s as if there’s a grain in the vinyl. Or could it have something to do with the blade angle or offset?

You are not the only one, I noticed that too as I do loads of tiny bits.
So I noticed that it weeds better if you weed same direction as the cutting direction. That means it doesn’t catch the small good bits up when you weed.
I don’t know the explanation but turning tangential mode on helps a lot (Mode 2 on Graphtec).

[Gary Barker]

micro mottling :claps:

we noticed with small text weed it straight away don’t leave it, i think the glue try’s to reconnect micro mottling ( made-up description ) back together, also have you tried weeding once you have applied it, sometime this works also.

[Gordon Smithard]

quote Gary Barker:

micro mottling :claps:

we noticed with small text weed it straight away don’t leave it, i think the glue try’s to reconnect micro mottling ( made-up description ) back together, also have you tried weeding once you have applied it, sometime this works also.

I have weeded some after applying and it does make it easier, but the stencils I cut are posted to the customer for them to stick down. I sometimes leave any extra small fiddly bits unweeded for them to weed after sticking down and they have no problem with that.

[Robert Lambie]

quote Gary Barker:

micro mottling :claps:

we noticed with small text weed it straight away don’t leave it, i think the glue try’s to reconnect micro mottling ( made-up description ) back together, also have you tried weeding once you have applied it, sometime this works also.

You could be right with some films Gary, Going back about 6+ years, i remember "a batch" problem with Oracal 651 and this was actually happening to an extent. If i am correct, i think it was more an issue in hot countries but was down to an isolated batch. but just goes to show this can actually happen.

[Phil Halling]

Slightly off your point but, I know from experience that Avery 900 series metallic silver definitely has some form of grain. When wrapping truck / trailer sides, you have to have all drops going in the same orientation off the roll or you will get a striped finish, and if you just get one the wrong way up it will leap out at you.

[Robert Lambie]

100% phil…
It is the same with all metalics mate. Same with colour shift wrapping films, brushed etc.
It is a common mistake i see with wraps posted online. Normally front and rear wings of cars. They do the side doors in one full piece then to save vinyl rotate the half sheet parts on the wings. Take the car outside in the sun and it stands out a mile due to the metalic sheen reflecting in different directions.

Metalics do tear easier when weeding and especially in colder weather, and during application.