# Hotflex Vinyl not sticking



## brooky (Oct 5, 2009)

ive been using hotflex vinyl from MPD for about 9 month and done about 500ish t-shirts but seem to have a re-occuring intermitent problem with the vinyl not sticking or not sticking properly.

i have read all associated posts and checked temperaure of heat press and it seems ok, about 2deg differenace over the plate, and pre pressing for 5-10 secs. 

generally when i switch the press on and do about 4 shirts i have no problem, but then it starts with the odd letter lifting when i remove the carrier? 

I have rechecked the temperature and it is still as set. 

When doing polo shirts, ie with a rougher fabric, you can clearly see a differeance between the letters that have stuck properly and the ones that dont, ie the properly stuck ones have the texture of the fabric, the others still feel smooth. 

is there anything i am missing?


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## 5'9" (Sep 21, 2009)

im having the same problem! also with MPD...


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## torodesigns (Jun 24, 2007)

Increase the pressure of the press . . . my embroider was running into this problem because her pressure was set for rhinestones. When I told her to increase the pressure for therma-flex or heat applied vinyl . . . she was totally happy that it was adhering to the shirts. So increase pressure and maybe bump up the time. for a once color design I do 18 -20 seconds . . . rub the graphic then peel. hope this helps.


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## 5'9" (Sep 21, 2009)

thanks increasing the time i think did make a difference, there still are little bits not sticking which i only know how to sort out with a second press once the backing is removed..


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## sjidohair (Apr 9, 2008)

I do the 20 sec press as well, and a final press once peeled, make sure and cover with protective sheet when post pressing, 
MMM


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## brooky (Oct 5, 2009)

the increased pressure seems to be helping, thanks, did 8 shirts tonight, 6 spot on, the last 2 slight problems on 1 letter on a 250mm square so nearly there, just a little more fettling i think, its always puzzled me as it does not seem consistent


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## brooky (Oct 5, 2009)

the plot thickens, most of the time it now works perfectly, but the odd colour just wont stick at all. is there a shelf life of this vinyl, is there something that affects the glue?


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## [email protected] (Aug 11, 2009)

I also use mdp and always have a problem with Navy Blue it never wants to stick, i tried xpres and used their ultra cut but it is exactly the same stuff both are made by politappe.de in germany. I personally think its a shelf life thing or the adhesive is not applied evenly when manufactured, must admit though the cool flex stuff works great everytime.


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## [email protected] (Aug 11, 2009)

oh also i press mine for 30 secs and the results are a lot better than using the rec time.


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## brooky (Oct 5, 2009)

[email protected] said:


> oh also i press mine for 30 secs and the results are a lot better than using the rec time.


the only colours that dont stick at 17 secs are white (sometimes) and dayglo yellow, all the rest seem perfect? in fact 17 secs is a little long for the silver.


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## c_invent (Jan 25, 2010)

Hello,

We are having the same problem to.. but I'm having the problem with more than one colour... it seems to be black, white & blue. They are the only ones I have tested.

I press at 160oC at 15secs (at mdp recommend) I phoned them up yesterday and they rang the supplier of hotflex and they had said try it at 170oC for 20secs so I have done this but still having the same problem....

If the shirt has also been washed before does this cause it a problem to? the shirts I'm printing on to are 100% polyester.

one last thing, if there is just a corner sticking up what can I do to stick this down as re-pressing it doesnt seem to work.

many thanks in advance


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## drtydave (Feb 8, 2009)

I've had problems before. One thing you have to take a good look at is your reliability of your heat press. Now i have used cheaper heat presses and use an IR thermometer to check the actual temp. I found it was out by 10 -15 deg at some points and that accross the platten it was varied. So basically your heat press may be giving you the wrong temp readout or the platten is uneven in places (common on value heat presses unfortunately).


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## retro_lad (Jul 6, 2010)

Don't know if this is still relevant but I've had similar experiences with Hotflex (white) on Blue 100% cotton T-shirts.
I found that by going over the vinyl (with parchment paper covering) with an iron on full heat. It really helped glue down any edges that were sticking up.
I also have a cheap press with uneven heat distribution. However I have an IR thermometer and I could see that the press was still hot enough when I was pressing the vinyl.
I'm going to throw them in the wash and see what happens.

I think the key process to follow is:

1) Don't treat the manufacturer's guides as 100% correct. Go hotter and press longer if you need too.
2) Once you've peeled the backing off, press again with parchment paper covering the vinyl. Do it until you are happy all corners or sharp edges are done.
3) Try to make notes on the various settings you use. It will probably help you achieve the correct settings that your setup needs to work well. More importantly if you've runined two t-shirts because the press wasn't hot enough or dwelled for long enough. Then it's silly to make the same mistake again. I've been on quite a learning curve, and I still know very little. However I tell myself that making mistakes is fine. Making the same mistakes isn't.


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## [email protected] (Aug 11, 2009)

just an update i now use magic touch premium flex and have had no problems with it at all, i personally think it was uneven heat distribution with my old clam press, cause since i upgraded to an adkins press everything seems to press better!!


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## Kim_t2_au (May 24, 2010)

Have you checked the temperatre on different parts of the press? I found mine is actually cooler in the middle than around the edges. I guess the element or whatever must be circular in shape or something like that. Also, when you repress to catch those bits that didn't afix the first time, it might be worth actually moving the shirt slightly incase there is a difference in the pressure across the press. Hope these thoguhts help.

Kim


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## vadan (Mar 9, 2010)

We use MDP hotflex no problems. 20 secs at 180. Tried all colours as we made sample wall charts for a local printer to show his clients.

Could it be the press is no getting hot enough or uneven platen, cold spots?

Will keep an eye on this from now on and report any change.

Speak to them about this they could have suggestions to help.


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## Froob (Aug 27, 2010)

With the garment vinyl from MDP you shouldn't pre-press it at all, neither the garment or the garment vinyl. It's a straight on application.


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## vadan (Mar 9, 2010)

Froob said:


> With the garment vinyl from MDP you shouldn't pre-press it at all, neither the garment or the garment vinyl. It's a straight on application.


May I ask why?


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## Froob (Aug 27, 2010)

Of Course, It's how the vinyl is designed, with the exception of Nylex which you do pre-heat. All the other flex materials you iron with the liner straight on, and job done, no pre-heating needed. It's pretty much standard these days with garment films.


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## sjidohair (Apr 9, 2008)

I always prepress my Garments to get excess moisture out, 
when applying all heat press vinyl, reg and glitter and holographic
MMM


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## vadan (Mar 9, 2010)

Froob said:


> Of Course, It's how the vinyl is designed, with the exception of Nylex which you do pre-heat. All the other flex materials you iron with the liner straight on, and job done, no pre-heating needed. It's pretty much standard these days with garment films.


Hmmmm i'm pretty sure most vinyl printers would disagree. Even imprintables warehouse recommend prepress to get moisture out and they are pros. 

We prepress all garments.


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## fub (Oct 2, 2010)

I've just had this problem too. Answer seems to be lower heat and definitely a shorter press time. I used 10 and 190 degrees and it worked perfectly. If the application vinyl starts crinkling up then you've pressed too long and too hard. I got the tip from another forum when I was at the point of throwing the vinyl out the window having wasted two shirts and lots of vinyl on what seemed an impossibly steep learning curve. Much happier now.


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## pew36 (Jul 17, 2011)

I have been trying 30 secs at 185c

Get some letters not sticking down.....it seems to be there are lots of contradicting advice on the matter. 

Personally I feel pretty bummed about the prospect of having to hand iron rogue bits because my heat press might be rubbish

Do folks think it is better to go hotter for a shorter time?

What is actually happening in the process? Is the vinyl melting into the shirts or is some glue released?

What are the consequences of over cooking?

I had a shirt crinkle a bit but that seemed to be from not enough pressure as it never happened again since I upped the pressure


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## funkytshirts (Jul 26, 2010)

Try letting the vinyl cool before pulling the backing off !


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## pew36 (Jul 17, 2011)

i tried that a couple of times and it makes the peeling of the backing even tougher. if i peel straight away it slides right off

besides, it isnt like im pulling the backing tape off and there is a battle of adhesion between the shirt and the backing tape, the vinyl is just plain not attaching to the shirt. irrespective of how long i leave the shirt.

and it isnt the heat process because i have since tried additional heat and repositioning the vinyl. its like either the vinyl is in patches not sticky or heat resistant.


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## pew36 (Jul 17, 2011)

i also did a shirt where i used a scalpel to ease the non stuck vinyl bits onto the shirt, then put grease proof paper down and heated that part again, and the vinyl just wasnt applying itself to the shirt.


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## mukka01 (Mar 31, 2013)

Hi 5'9 i use the same vinyl you are talking about, i press using a geo knight dk20 with medium to heavy pressure at 15 seconds. I did try what you do only 10 seconds and after cooling it is easy to peel off. 160* for 15/17 seconds med/ heavy pressure works a treat, only thing i can think of is uneven heat on your press, worth spending more on good quality press, try above settings and it should be fine,, also hot peel. Hope this helps.. Newbie to the forum, hi to all.


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## mukka01 (Mar 31, 2013)

Pew36... Seriously sounds like a pressure issue.... If you are certain that the heat is 160* and pressing for 15-20 sec then it will be down to the pressure, medium heavy pressure, light or not enough pressure will be useless,,,,


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## mukka01 (Mar 31, 2013)

All i use is hotflex from MDP. I have zero errors with it and i have been using it for the past yr. I press at 160* for 15 seconds, i supply kebab shops and they go through serious rough and tumble and cleaned daily, i have not had a single item returned regarding the vinyl. I am certain the fault people are having is nit the product but the press, cheap presses are a complete waste of money, i use a geo knight 20x16 and it gives heat all the way through out the platen, people do not realise how important the press is, it is your main piece of kit, it is not the vinyl it is the press, MDP are really helpfull and i have well over 500 sheets of hotflex and i know without any doubt i can produce products that will last. Please try and purchase a branded press, read reviews stay away from garbage on ebay kits, i would not pay £50 for them.


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## MissChris (Apr 24, 2013)

Sorry for bumping an old thread!

I have had this problem before - I had black hot flex from MDP and it would not even weed properly from the backing. It was horrible then would not stick so I ended up binning it.

I have recently done a large order using their Golden Yellow Hot Flex which felt Ok. It would not stick very well but eventually got round that with some of the methods mentioned, however I recently had the customer contact me to say that the majority of the lettering has fallen off. I am absolutely shocked and embarrassed!

Have done this exact order before and had no problems at all. So very annoyed that a return customer has now had such a terrible experience. I am trying to find the cause before completing other large orders.

Could I have had a dodgy batch of Vinyl? or Should I be getting a new Heat Press?


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