Join our Premium Membership now and save with Xpres, Listawood, Ink Experts, Ink Express and more! Just £10 per year.....Click the Membership link above.....

User Tag List

Similar Threads

  1. Vinyl Not Sticking
    By reens80 in forum Vinyl & Flock
    Replies: 3
    Last Post: 05-12-2018, 12:36 PM
  2. Replies: 11
    Last Post: 16-01-2014, 08:24 PM
  3. vinyl backing sticking to tee shirt
    By plugy in forum Vinyl & Flock
    Replies: 7
    Last Post: 13-06-2012, 05:24 PM
  4. Vinyl not sticking
    By plugy in forum Vinyl & Flock
    Replies: 10
    Last Post: 29-05-2012, 11:56 AM
  5. Does this look like vinyl/flex to you
    By mrs maggot in forum Vinyl & Flock
    Replies: 9
    Last Post: 11-02-2011, 01:25 PM
Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. #1
    Junior Member
    Join Date
    May 2020
    Location
    Stockport
    Posts
    16
    Downloads
    15
    Uploads
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    MDP hot flex vinyl not sticking

    Good afternoon,
    I am hoping by posting this we can get to the root cause of the problem i am currently having.
    Its to do with MDP hotflex vinyl not sticking to the cotton t shirts.
    I have looked through various old threads and posts today to try and find anything out of the ordinary i am doing.

    Context
    I have been asked to print some stag do t shirts for someone at work by the end of next week.

    Materials
    I have bought pink 100% cotton vauleweight t-shirts from MDP, bought this week.
    I am using hot flex vinyl from MDP, bought this week.
    Heat press is an ink experts 50x40cm flat bed clam press.

    Process
    Place the t shirts onto the lower platen (not threaded as most medium and large t shirts don't particularly stretch over it)
    No seems or anything in the press area.
    Pre press the t shirt for a few seconds to take out moisture, front and back.
    Press the vinyl onto the t shirt with a thin Teflon sheet on the top, for 160 degrees, 15 secs, hot peel.
    Remove film and re press again for a further 5 seconds with a Teflon sheet on the top.
    Turn the t shirt over and do the same with the text on the other side.
    Hang up on a hanger and the next day put them in a carrier bag to take to work.

    I have given the t shirts to my friend to try on, and the letters on this particular one basically fell off in front of me.

    Totally embarrassed (and slightly stressed) I said I would re do them all.
    Theres a couple where the edges of the letters are not fully stuck.
    Although last night they looked completely fine.

    Can you see if there's anything wrong with the procedure?..

    Should I stretch the t shirt straight after the pressing??
    Is it the pressure, being too light?


    When removing the film, on this particular t shirt i do remember i had to do it a couple of times as a couple of the letters were peeling with it.
    So i re pressed, adding a 1/3 or 1/4 turn to the pressure setting.
    But it looked fine before taking into work this morning.

    Any advice would be appreciated.

    image 2 set up of press-shirt-sheet etc.jpgimage 1 of letters.jpg

  2. #2
    Senior Member
    Join Date
    Nov 2015
    Location
    dorchester
    Posts
    1,246
    Downloads
    0
    Uploads
    0
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Have you got the heatpress set to fahrenheiht by mistake? Or is the heatpress faulty?
    I used to use Hot Flex as my go to vinyl. The only time I had problems was when they sent cold peel by mistake.

  3. #3
    Junior Member
    Join Date
    May 2020
    Location
    Stockport
    Posts
    16
    Downloads
    15
    Uploads
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thank you PW66,

    I have checked and double checked the settings, set to degrees C, all ok.
    Heat press is only about 2 years old if that.... Only gets used once a week for my own little projects.

    I have previously done checks with a heat gun to check the temp across the top plate (basically comparing it to my old cheap press)

    Checked my emails/receipts and it says Hot flex Ultra.
    I actually picked the vinyl up from the MDP shop, but im not able to tell visually if its flex, hot flex etc by eye.

    So i am pointing to either incorrect supply of vinyl
    Or pressure being used.

    I'm afraid of leaving scorch marks - but maybe im too light on the pressure perhaps.

    Plus where possible i will thread the t shirt over the bottom platen and see what happens with any peeling overnight.

  4. #4
    Junior Member
    Join Date
    May 2020
    Location
    Stockport
    Posts
    16
    Downloads
    15
    Uploads
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    This morning it seems on this XXL t shirt, the vinyl is easily peeling off with very little effort.
    This particular shirt was the one with the letters falling off yesterday.
    Doing a pull/stretch test with a little bit of force is lifting the letters....

    Yesterday i threaded the t shirt over the press again and gave each side a press again, so it seems this particular shirt is still not allowing the vinyl to stick as it should be doing.

    The other 4 shirts seem relatively ok, some very slight peeling at the edges, concerning but not my biggest issue right now.
    But a stronger pull test on these medium and XL shirts may lift the letters off.

    Having done a slight pull/stretch test Pull test XXL day after printing.jpg

  5. #5
    Senior Member
    Join Date
    Nov 2015
    Location
    dorchester
    Posts
    1,246
    Downloads
    0
    Uploads
    0
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Possibly a faulty batch? The issue I had with cold peel instead of hot peel was probably a picking error in the warehouse so didn't show on the invoice.

    Are you printying front and back? If you are without threading the shirt it could be that the second pressing is effecting the vinyl from the first pressing. I would say the only way around that would be to do a 5 sec tacking press on the front (without peeling) and then flip the t-shirt over and press the back print for the full 15 secs. Go up to 165c and increase the pressure.

    Did you do a wash test? Some vinyls stipulate no laundering within 24 hours of pressing.

    The best way to check if it is faulty vinyl is to cut a small piece and apply it to a waste t-shirt. If it sticks ok to the test shirt then it is the double pressing causing the issue.

    The only other thing I can think of is have the t-shirts been pre washed? I have had an adhesion issue in the past using second hand t-shirts that have had fabric conditioner applied by the customer before printing.

  6. #6
    Junior Member
    Join Date
    May 2020
    Location
    Stockport
    Posts
    16
    Downloads
    15
    Uploads
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Hi,

    Yes i am printing front and back.
    I was printing the back of the shirt first (as they were all different text).
    Pressing, peeling and then giving the vinyl an extra 5 secs or so re-press.

    Then turning the shirt over and applying, pressing the front, same procedure.
    Not threading the shirt, on either side, just laying flat on the press when doing front and back presses.

    Then moving onto the next shirt, rinse and repeat the above process.

    Ive not washed the t shirts and have printed on them straight from collecting them from MDP.
    They havent been washed after a press either.

    I will do a test t-shirt later today after work.

    All helpful advice, I really appreciate it.

    Just very frustrating as you can imagine.

  7. #7
    Senior Member
    Join Date
    Nov 2015
    Location
    dorchester
    Posts
    1,246
    Downloads
    0
    Uploads
    0
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Is the problem only effecting the first side you print? If you are not threading the shirt then the first side you print is effectively being pressed for 40 secs, which is why I suggested a tacking press for 5 secs before flipping the shirt and adding the second print. That will reduce the time the first print is being overpressed for.

  8. #8
    Administrator Justin's Avatar
    Join Date
    Sep 2009
    Location
    Derbyshire
    Posts
    10,354
    Downloads
    7
    Uploads
    1
    Mentioned
    41 Post(s)
    Tagged
    7 Thread(s)
    Have you checked with MDP? In your photo the material looks like a matte finish? Doesn't look particularly like garment vinyl so maybe worth a check. Just playing devils advocate but it is the right way around isn't it?
    Membership scheme now available - Just £10 per year - Regular Supplier Discounts and Special Offers!

  9. #9
    Junior Member
    Join Date
    May 2020
    Location
    Stockport
    Posts
    16
    Downloads
    15
    Uploads
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Im heading to MDP tomorrow hopefully.
    I have been in email contact with their customer service dept asking if there's a possibility of a picking error (it was Friday afternoon after all when i bought it).

    They asked me to do another one in the mean time as per the instructions etc.
    So now I have printed a new one, step by step from their own instructions, and increased pressure to medium-high like their email asked.
    pre heat t-shirt
    I threaded the t shirt over, pressed for 15 secs, and during the hot peel, the letters began to peel with it. (see photos).

    So hopefully this rules out the pressing double sided issue, and PW66 is correct, im not helping matters by pressing the first side for about 40 seconds.
    So that is one lesson learned i hadn't thought of.

    So i will head there tomorrow and take a sample with me.

    How vinyl looks when hot 160 degs 15 secs.jpgLetters peeling off during hot peel.jpg

  10. #10
    Junior Member
    Join Date
    May 2020
    Location
    Stockport
    Posts
    16
    Downloads
    15
    Uploads
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Just to provide an update on this.
    I got some new hotflex vinyl from MDP to eliminate this being the issue.
    Printed one or two more t-shirts but still having issues, so im now leaning towards the heat press being the issue.

    I have checked the pressure using a piece of paper and ensuring there is some resistance when pulling it from a closed press.Heat press temp check.jpgIMG_20250213_155248.jpgIMG_20250213_155340.jpg

    Set the heat press to 150 degrees C and when it reaches this temp, i have taken a reading in all 4 corners and the middle of top plate.
    Mixed readings from 114 (top left), 112 (top right), 123 (bottom left), 114 (bottom right) and 121 (middle).

    Press the heat press down for 10 seconds and then i wanted to see what temperature was being transferred onto the bottom half.
    Back left - 80 degrees, Back right - 73 degrees, Front right - 76 degrees, front left - 70 degrees, middle 77 degrees.

    The top plate i would have thought would have been higher and not 20-30 degrees lower.
    I assume the teflon sheet will absorb some of the heat being transferred but not sure what readings i should expect.

    So maybe i needed to press at higher temp setting.

    Should i increase the temp until the top plate reads 140-150 degrees?
    Who knows.

    Anyway, not sure if this helps anyone but just wanted to share my experience in case anyone has same/similar issues or further advice.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •