problems with application tape. vinyl keeps coming off.

[Jill Marie Welsh]

Try a dry app on windows.
If you must use a wet app try Rapid Tac 2.
http://www.rapidtac.com/products/tac2.html
I spray the window, spray the decal (adhesive side after removing backing)
apply, squeegee the bejeezus out of it, then spray the application tape while still on the window, then squeegee it again.
It usually peels right off.
Make sure your windows are sparking clean to start with and also that it’s not too cold or damp out.
Love….Jill

[John Childs]

quote k wrap:

when wet applying vinyl on to windows my vinyl keeps coming off with the application tape. why is this??

That’s an easy one.

There is more adhesion between the app tape and the vinyl than between the vinyl and the glass.

To reverse that situation you have got to apply the vinyl dry, or leave peeling the app tape until things have dried out completely. Sometime the next day would be about right, depending on temperatures.

[Peter Dee]

With a name of "k wrap" this has got to be a wind up!

[Stuart Green]

lol.didnt know what else to have as a username!

[Karl Williams]

edited before the mods do it. 😉

[Ian Muir]

Applying to windows dry can be a problem if you’re not used to it.

Applying to windows in general is a problem at first cos the glass ‘follows ‘the surrounding temperatures more so then metal + when it’s wet and you apply then the water does not escape when squeegying like other substates.

I would suggest feeling your way with it, e.g. spray a little water on the glass (no soap in it) then wipe most of it off until it’s nearly dry, you can tell by trying to press a bit of vinyl onto it, if it bites a little then good, if not then dry it some more until it does bite (careful if you choose to use a heatgun)…

Not exact science but it works for me…. :lol1:

[Jill Marie Welsh]

quote :

(careful if you choose to use a heatgun)

I would say NEVER use a heat gun on glass.
Not unless you feel like replacing a cracked window.
😳
Also be careful of putting large areas of black paint or vinyl on glass.
Not that this has anything to do with the OP.

[Peter Normington]

quote Jillbeans:

quote :

(careful if you choose to use a heatgun)

I would say NEVER use a heat gun on glass.
Not unless you feel like replacing a cracked window.
😳
Also be careful of putting large areas of black paint or vinyl on glass.
Not that this has anything to do with the OP.

Its a bit of a myth that heat guns will crack glass.
maybe if you turned it up to full power and held it within an inch for a few minutes.
Glass is a pretty tough material, if it cracked easily with temperature differentials, then it could not be used in skyscraper windows, or even car windscreens.
Think of a winter morning, ice on the outside and demister going full tilt, does your windscreen shatter?
and before anyone comes up with "a car windscreen is laminated or toughened" it has nothing to do with why it breaks, just do do with how it breaks.

Peter

Not that you should need to use a heat gun on a window anyway 😀

Peter

[Jill Marie Welsh]

I was referring more to older shop front windows.
😉

[Phill Fenton]

Once again Peter you know you are playing Devils advocate and talking rubbish 😕

So how come a number of experienced signmakers can recite tales of when they flood coated a window it cracked – or likewise, when using a heat gun to remove vinyl it cracked.

Presumably they imagined or dreamt it 😕

[Peter Normington]

Phill
can you site these instances?
Peter

[Robert Lambie]

too much heat in one area of the glass does crack it peter.

i wasn’t on site at the time, so don’t know the real story but one of our new guys cracked a customers window many years ago.

one of our customers who is a family friend also broke a large window in the city using a heat gun to remove vinyl. this was only months ago… said he wasn’t using much heat but was heating one area down low on the window. one minute all was fine, next a big bang and the window had cracked. this was a large OLD window which ide expect much easier to break.

applying vinyl ill only do it dry, its the quickest and best way to apply vinyl. especially on glass. as i have said, if it MUST be wet, then rapidtac2 will do it, even then it must be a very light mist of the stuff.

removing vinyl from glass, ill use a blade scraper every time if the vinyl is brittle or slow at coming off.

[Phill Fenton]

Sorry Peter your question makes no sense at all?

Did you mean "Cite"?

[Peter Normington]

OK Rob and Phill
heresay is fine
better stop the sun shining on a window in summer then, otherwise it will shatter.
can you explain why a windscreen does not shatter when the heater is turned on when there is ice outside then?

Peter

[Robert Lambie]

different type of glass peter, different circumstances, different age of glass and so on… bottom line is, none of us are experts but it can and does happen. better to point this out than to say it doesn’t happen though mate.
personally, we have already footed the bill for a customers window as a result of one of our guys, once bitten and all that… not just hearsay. 😀

[Phill Fenton]

The heat from a heated window element is miniscule in comparison to a heat gun.

Likewise – when the sun shines on a window on a sunny day most of the radiation passes through the glass and heats up the room.

If the glass has an opaque film applied – the energy does not get into the room but is absorbed by the glass – resulting in the glass heating up and thermal expansion causing cracking. On modern skyscrapers, frames are designed to allow for thermal expansion. Older buildings – less so 😕

Peter, If you are going to pro-fer advice ensure it is sound, otherwise the advice you give out may cause problems for some 😕

[Robert Lambie]

taken from the web…

quote :

Question – Why do glass tumblers break on pouring hot water
suddenly?
—————————————————–
When hot water is poured into a tumbler there is an uneven increase in the
thermal expansion of the walls of the vessel. If the expansion is uneven
enough and the strength of the glass is not strong enough, the tumbler
breaks.

Vince Calder
=====================================================
This is a simple problem that is not simple to explain. There are two things
to keep in mind. 1) Materials like glass are brittle and cannot bend very
far without breaking. 2) Materials like glass expand when they get warmer.

Simply stated, when the hot water is poured into the tumbler, some parts of
the glass warm up quickly (like the sides which are thin.) These parts
expand. However, they are still attached to the thicker parts of the
glass (like the bottom), which have not expanded. This difference in
expansion sets up strong forces in the glass which can break it.

If you put a tumbler into an oven and warm it up slowly, you do not get this
problem. As the glass warms up, it gets large in all directions. No
stresses.

Thermal stresses are a problem not only for glass, but for thick pieces of
metal, masonry and so on. Almost anything that is fairly stiff and brittle
can have this problem. Large metal parts sometimes require days to cool
down or they will crack.

You may wonder, how can a little bit of heat crack a large, strong metal or
glass object? It is because thermal expansion in solids is a very strong
force.

If you put a solid piece of glass in boiling water, it will expand about
0.02%. Maybe thousandths of an inch. That is not a lot. But if you tried
to prevent it from expanding by putting a large clamp on it, you would need
to squeeze it with a force of 2000 pounds per square inch to completely
eliminate the expansion. The piece of glass does not expand far, but if you
try to prevent it from expanding, it will push VERY hard.

Clearly, if part of the tumbler is warm and part is cold, thousands of
pounds of force can occur, which will break the glass.

[Peter Normington]

OK Phill
your experience is far superior to mine, after all you have written a book about signs.
Your example Rob is extreme differentials in heat which I did say would crack glass

DO NOT USE HOT AIR ON GLASS IT WILL CRACK.

Phill and Rob say so

Peter

[Peter Normington]

quote Phill:

The heat from a heated window element is miniscule in comparison to a heat gun.

Likewise – when the sun shines on a window on a sunny day most of the radiation passes through the glass and heats up the room.

If the glass has an opaque film applied – the energy does not get into the room but is absorbed by the glass – resulting in the glass heating up and thermal expansion causing cracking. On modern skyscrapers, frames are designed to allow for thermal expansion. Older buildings – less so 😕

Peter, If you are going to pro-fer advice ensure it is sound, otherwise the advice you give out may cause problems for some 😕

I did not mention the heating element, I was talking about full heat from the demisting system,
All windows have allowances for expasion, even older ones, thats why putty was used. lead was used in church windows for a similar reason.

Peter

[John Childs]

I believe that a heat gun will crack glass too, but only if it isn’t used properly.

On cold glass, a heat gun can cause a local expansion, if not held far enough away and waved around a lot to heat a bigger area. If not the hot bit of glass tries to expand, and it can’t because the cold bit surrounding it won’t let it. The resulting internal stresses will cause a fracture.

Sun won’t cause a window to crack because the heating effect is a lot more gentle, and spread more evenly across the glass, giving lower stresses.

Windscreen blowers are a lot more gentle than hot air guns because they pass a lot more air through them. In fact the only difference between a hot air gun and a hair dryer is that, although they are both generally in the 1,500 watt range, the hair dryer passes a much greater volume of air. So, same power, but I know which one I would prefer to dry my hair with. (Assuming that I was gay enough to use a hair dryer at all). 😀

There is a difference between float glass and laminated, and you can prove it yourself by trying to twist it. Solid glass, say 6mm, will take a lot more bending and abuse than an equivalent thickness laminated. That’s because, with laminated, the thickness of the actual glass sheets on either side of the laminate is only about 2.5mm. Therefore it can take less stresses before it breaks.

That’s why you can’t use laminated glass in things like wardrobe doors. It breaks too easily when little Johnny runs his toy car into it. In those circumstances you have to use toughened glass with a safety film applied to one side or the other.

[Karl Williams]

I’ve used a heat gun a few times on glass. You just have to do it conservatively. Any numpty should know that to much heat in one place for to long will damage the subsrate either be it glass, perspex or even paint on a vehicle. When a house goes up in flames the windows break because of the heat…use a heat gun to high like I said and bang goes the window. I can’t understand the argument as it’s a general law of physics…..heat can destroy anything. Christ, even railway sleepers bend on a hot day.

[John Childs]

Oh yeah, I forgot……

On similar lines, borosilicate glass (Pyrex) has a coefficient of expansion of something like 30, as compared to the 85ish of the float glass used in windows and most bottles.

That’s about a third of the expansion in Pyrex, which is why it’s safer for use in ovens.

[Karl Williams]

quote John Childs:

Oh yeah, I forgot……

On similar lines, borosilicate glass (Pyrex) has a coefficient of expansion of something like 30, as compared to the 85ish of the float glass used in windows and most bottles.

That’s about a third of the expansion in Pyrex, which is why it’s safer for use in ovens.

And pyrex cracks straight away if placed cold water. So it’s the same as taking the glass from one extreme to the other. To much heat…bang. Hot pyrex glass to gold water….bang. It’s just a case of using your noddle and taking care.

[John Childs]

quote Karl Williams:

And pyrex cracks straight away if placed cold water. So it’s the same as taking the glass from one extreme to the other. To much heat…bang. Hot pyrex glass to gold water….bang.

I’ll take your word for that Karl.

The kitchen isn’t my area of expertise. 🙁

The dining room is though. 😀

[Karl Williams]

quote John Childs:

quote Karl Williams:

And pyrex cracks straight away if placed cold water. So it’s the same as taking the glass from one extreme to the other. To much heat…bang. Hot pyrex glass to gold water….bang.

I’ll take your word for that Karl.

The kitchen isn’t my area of expertise. 🙁

The dining room is though. 😀

Yes John. Not long after I met Cheryl she went to great effort to make a lovely meal. We both served it up. Then like a complete and utter knob I put the Pyrex dish straight in the sink. Lets just say that’s the only thing that went bang that night. 🙁 🙁 🙁 😳 😳 😉

[Martin Pearson]

Karl, can you delete your post on the first page of this thread please, nearly went into shock when I read it !!!

[Karl Williams]

quote Martin:

Karl, can you delete your post on the first page of this thread please, nearly went into shock when I read it !!!

Why’s that then Martin?

[Martin Pearson]

Ask Robert at signuk next year, he knows how I started in the sign business 😉

[Karl Williams]

quote Martin:

Ask Robert at signuk next year, he knows how I started in the sign business 😉

No…Sign-a-rama?……You?

[Phill Fenton]

quote Peter Normington:

All windows have allowances for expasion, even older ones, thats why putty was used. lead was used in church windows for a similar reason.

Peter

If you examine the cracked glass on a window that has been installed using putty you will normally find a nail at the point where the crack began. This is because glaziers used small nails to hold the pane in place before fitting the putty and often either forgetting or not realising to remove the pins again once the putty had dried. As a result the pins that have been left in place do not allow the glass to expand and the crack results.

Sorry Peter – I was having so much fun last night I just had to re-surrect this thread :lol1: :lol1:

[Phill Fenton]

quote Karl Williams:

quote Martin:

Ask Robert at signuk next year, he knows how I started in the sign business 😉

No…Sign-a-rama?……You?

That was funny :lol1: :lol1: :lol1:

[Stuart Miller]

quote Peter Normington:

quote Jillbeans:

(careful if you choose to use a heatgun)

Its a bit of a myth that heat guns will crack glass.
maybe if you turned it up to full power and held it within an inch for a few minutes.
Glass is a pretty tough material, if it cracked easily with temperature differentials, then it could not be used in skyscraper windows, or even car windscreens.
Think of a winter morning, ice on the outside and demister going full tilt, does your windscreen shatter?
and before anyone comes up with “a car windscreen is laminated or toughened” it has nothing to do with why it breaks, just do do with how it breaks.

Peter

Not that you should need to use a heat gun on a window anyway 😀

Peter

Heat guns will crack annealed or laminated glass, do not use them.

There is a difference as to why Annealed/Laminated glass cracks more easily than toughened

Toughened glass is made by heat treating which seals any cracks in the glass (particularly around the edges) and changes its properties. It also produces a smooth sealed edge to the glass and is made to a specific size. It is very unlikely to crack from thermal stress induced by a heat gun.

Laminated glass on car windscreens can be more of a problem and can not take high heat from a heat gun. There are many instances where window tinters have cracked laminated glass. Winscreen demisters are not very high heat and not concentrating on small spots.

Most shop windows in my experience are single glazed annealed (basic float glass) or laminated glass.
Laminated glass is usually just two layers of annealed glass with a thin plastic layer in between.
Annealed glass is very likely to crack when heat is applied due to thermal stress as the edges of the panes contain many micro cracks from the way it is cut to size. The larger the pane the more likely the glass will be under stress and it is known that there are maximum sizes a pane can be before the likely hood of spontaneous propagation of these cracks can occur even without any heat. Building regulations and glaziers do take into account the largest pane size being used to reduce this risk this.

Thermal stress where heat is concentrated on a small area compared to the size of the pane is much more likely to cause these already existing tiny cracks to propagate.
As window tinters we are therefore advised to never use heat on annealed or laminated glass, but toughened car glass no problem.

Having said all that I did have a problem area with a frosted graphic sticking on a hairdressers window which suffered from constant condensation. I didn’t dare use my heat gun but gentle warmth from a hairdryer did save the day. Just dont get the glass hot.
Stuart

[Phill Fenton]

quote Peter Normington:

OK Rob and Phill
heresay is fine
better stop the sun shining on a window in summer then, otherwise it will shatter.
can you explain why a windscreen does not shatter when the heater is turned on when there is ice outside then?

Peter

Would you believe it. I was driving in to work this morning in the Mondeo. The temperature was -3 outside. The screen had already defrosted yet about halfway to work the windscreen spontaneously cracked. I wasn’t hit by flying debris or anything, but the car was just starting to get warmed up properly when the glass broke.

I’m not crowing or anything…. to be honest I’d rather have been proven wrong than have a cracked windscreen 😕

[Peter Normington]

yes I would believe it Phil
but it was nothing to do with the heat, otherwise all the cars in Scotland would have suffered the same fate, you either had a previous stone chip that developed, or a even though you say you were not hit by debris, like a stone, how do you know you were not?

Peter

[Phill Fenton]

The crack is internal – the outer layer of glass is as smooth as a babies bum 😕

[John Childs]

quote Phill:

The crack is internal

Anybody been wiping the screen whilst wearing a diamond ring?

An old favourite from my days in the trade. 😀

[Peter Normington]

Phil. I have no idea why your screen cracked,
but it was not due to temperature differentials between the outside and inside, otherwise it would be a common occurrence, and it clearly is not. You do seem to be one of those people that sh1t happens to though, according to your recent posts.,
I feel for you,

Peter

[Phill Fenton]

quote John Childs:

Anybody been wiping the screen whilst wearing a diamond ring?

That’ll be Alison then 😕

But given Peters reassurances that thermal shock is not to blame – what on earth could have caused the crack to appear whilst I was driving at a temperature of -3C (external) with my cars heater blowing at maximum heat internally onto the front screen?

[Peter Normington]

Phil
I do a lot of work for a national windscreen company,
I will give them a call in the morning, and ask if they can shed any light on your incident.

Peter

[Gwaredd Steele]

Just to add that I’ve never had a window pane crack on me whilst using a heat gun. I think common sense is the key to using one & if it’s very cold, you obviously have to gradually warm the panel up evenly.

As Peter says, if you concentrate heat in one area for a long period, you’re asking for trouble.

On a similar note, I’ve also never had a cracked windscreen by pouring warm water on it when frozen contrary to popular belief/myth. Now if you were to tip boiling hot onto it, that would be a different story & the same level of stupidity as pouring hot water into a cold glass tumbler.

It’s all about thermal expansion folks :rabble: 😉

[Gavin MacMillan]

-3? Is it a girls car…? It was minus 15 here at the coldest and no cracked windscreens… I don’t really care though just wanted to sound like I can handle the cold even though I never went too far from the comfort of a heater!

[Phill Fenton]

Yes it is a girls car – it’s Alisons. I usually drive the van but had to take the car to work that day :lol1:

[Phill Fenton]

Well the man came and fitted a new screen today. On closer inspection there was a slight stone chip on the outside that is suspected of causing the crack.

Alison has now been absolved of all suspicions of causing the crack. Her defence of "I don’t have any diamond rings – they’re all cubic Zircona you cheapskate" has been accepted as a suitable alibi 😕

[John Childs]

quote Phill:

Alison has now been absolved of all suspicions of causing the crack. Her defence of "I don’t have any diamond rings – they’re all cubic Zircona you cheapskate" has been accepted as a suitable alibi 😕

Is it safe for me to raise my head above the parapet now then? 😀

[Phill Fenton]

Not really – you’re accused of mudslinging (puppy-eyes)

[John Childs]

quote Phill:

Not really – you’re accused of mudslinging (puppy-eyes)

OK. Message received. :peek: