Mastering The Basics
"It's been my vision and passion since 2006 to help Australian decoration businesses by making heat transfer as easy as possible. Below are the top tips I pass on to EVERY business I work with and help"
TIP 1: The 3 Elements of a perfect heat transfer application
It's fairly simple, enough heat for a few secs with even downward pressure and transfers will stick. Let's look at more specific recommendations for most digital transfers:
Temperature: Range 135 - 155 degrees Celsius
Pressure: Even and moderate
Time: Between 6-12 secs
NOTE: These three elements are inversely related. Meaning if you need to decrease one element, you can often compensate by increasing another... example, if you need to have a lower range temp due to fabric sensitivity, increasing the time will help compensate and bond the transfer.
Tip 2: Is a Pre-Press necessary?
A lot of recommendations by heat transfer suppliers recommend doing a 1-5 sec pre-press before placing down the transfer, this advise is the same as recommending everyone to hand wash inside out in cold water all your clothes, sure it'll guarantee the best quality wash but is it necessary...
Lets first understand why you would do a pre-press, allowing you to make the decision to the day with the fabric and transfer you're applying in front of you.
#1 - Remove moisture from the fabric. If it's humid or you're garments are damp, then the moisture will steam when you first apply heat, this is 'not' good for applying transfers, so if you see steam then i suggest doing a quick pre-press to remove the moisture before applying transfers
#2 - Remove creases. Some fabric just won't lay flat on your press plate, to help ensure no creases gather below your transfer during application, give it a quick pre-press.
#3 - Heat sensitive fabric. Often heat sensitive fabric will 'shrink' when heat is applied, think umbrellas, nylon drawstring bags, some tote bags... giving a pre-press will help stabalise the fabric first before applying the transfer. See below TIP on shrinking fabric for more info
#4 - To lower application time. If you're finding that the fabric is warping during application, then a short as possible application time is preferred, so to achieve this do a quick pre-press, get heat into the fabric so that the transfer adheres quickly allowing you to reduce application time.
TIP 3: First press on a new fabric? Start at the lowest range of temp and work up!
Garments are the most expensive element of heat transfer printing, so to ensure you don't damage any and waste time and money, follow these steps:
#1 - ALWAYS start your temp at the lowest end of the recommended heat temp for that transfer.
#2 - After the first press, check if it's completely bonded the glue or requires more temp or time. If so, increase by 5 degrees or 2 secs.
#3 - The ultimate goal to achieving the Perfect Press, is to apply transfers with as low a temp as possible that perfectly melts the transfer glue and it adheres without any lift or edges.
You’ll never damage a bag, cap or tshirt if you start too low, you can always increase your temp and time… BUT you can ruin a garment if you press too hot for too long, and that you can't fix.
So, start low and then increase your temp and time until it presses PERFECTLY.
TIP 4: The type of 'fabric' matters
The simplest way to understand difference in fabric is to think 'Natural Vs Synthetic' fabrics... ie Cotton Vs Nylon.
So often i walk into a print shop and they don't change their press temp or time regardless of what fabric or garment they're pressing.... cotton tshirt or nylon umbrella. It should just work right? Wrong.
- Cotton: Natural fibre, holds moisture and takes more heat and time to heat up.
- Polyester blend: Synthetic and natural blend. Heats up quickly but can hold moisture as well.
- 100% Polyester:
- Nylon: Synthetic and often thin. No moisture content, heats up very quickly and can shrink if too hot for too long
- Tote Ba: Synthetic and very sensitive to heat.
When applying a transfer, it's about getting the 'glue' upto it's melting temp, now if it's onto a thick cotton then this will require MORE temp and time to heat all the moisture and cotton to get the glue to melting temp Vs a thin Nylon fabric that has minimal moisture and will heat up 'very quickly'.
If you press cotton tshirts at 145-150 degrees for 8-10 secs, i would recommend dropping your temp to 138-140 degrees and 6-8 secs when applying to thin made-made fabrics.
Again, always start lower temp range and increase until you find the perfect settings.
TIP 5: Fabrics 'shrink' when pressed
Shrinking fabric while pressing can cause major problems, especially if your transfer is quite large or the fabric is not 'stretchy'.
Here's how to identify if your fabric is shrinking:
- when you do your press, if the transfer liner is 'bubbly', 'cockling' or 'wavey' then this is because the plastic liner won't shrink but the fabric underneath it is! So the plastic bubbles to compensate but this 'lifts' your transfer from the fabric causing edges to lift and you'll get a 'poor' application.
If you notice this, then you need to do 1 of the below 2 options:
#1 - Pre-Press the fabric. Make sure the time you pre-press for is 'longer' than the time you're going to press the transfer, this will ensure the fabric does all it's shrinking first and is stable when you apply the transfer.
#2 - Short 1st Press, Remove liner, Second Press. This method is useful if you can apply the transfer with a quick press, lightly applying the transfer so that you can remove the liner and then do a second 'longer' press with a piece of fabric, transfer paper or teflon covering the transfer. The second press will give you the best press result and allow the fabric to 'shrink' but not causing application issues.
TIP 6: Transfer not sticking? Too much heat most likely the cause!
It's the common thought, transfer not sticking, i'll increase the temperature, time and pressure.
- 9 out of 10 cases, higher temperature will only make application harder -
Today's transfers are being developed to apply at LOWER temps and times than ever before, it's to protect the garment and make application easy. For a perfect press with the liner releasing easily, the transfer glue needs to be able to drop below it's 'melting temp' point and harden slightly as soon as the plate lifts, holding the transfer in place.
If too hot or pressed too long, the transfer can't cool fast enough below it's 'melting point' and so the liner will lift the transfer. Other issues can also be glue squeezed out around the edges of the transfer or worse become too liquid and pushed too far into the garment no longer bonding strongly between transfer and fabric.
Remember if a transfer isn't sticking easily, check that the application area is flat and free of any creases or raised fabric that will take pressure away from the transfer. Then, think if you're within the transfer application window, try reducing the temp down significantly first (i've seen 130 degrees work like magic where 150 degrees wasn't) and working your way up to find the perfect temp and time.
TIP 7: Hot Bottom.... plate? It happens and matters.
When you turn on your press and do the first press or setup the ideal temp and time, your bottom plate is typically cold. This allows the garment and transfer to cool quickly once the top heat plate is lifted, making transfers apply perfectly.
However after 20x or so presses, you'll find your bottom plate may start getting hot, particularly if you're pressing quickly.
If you find the first 20x presses were perfect, but then you transfers start to lift a little or application isn't as smooth as originally, think of TIP 6 above, as you're now heating the transfer from top AND bottom, and this may mean you need to drop your top plate temp by 5-10 degrees.
Remember if you stop for an extended period of time, you may need to raise your temp slightly again as you get the first few presses done.
TIP 8: The perfect textured finish
Digital transfers are technically plastic adhered to fabric, the challenge is making sure they don't look like 'stickers' and closely represent printed fabric.
The best way to achieve this, is with a quick second press for 3-5 secs after you've removed the transfer liner, the secret being with a thin cotton or polyester covering the transfer.
The transfer in this instance, will not longer have the smooth finish of the plastic liner, but a matte texture as it's moulded between two textured surfaces. The added benefit being if any glue has squeezed out underneath the transfer, this glue often sticks to the laid fabric and visually disappears giving you the perfect transfer look.
NOTE: A second press should not be necessary for good application and washability, it is in most cases purely for visual appearance but it will give you extra assurance of the perfect transfer application also.
TIP 9: Best wash durability after 24 hours.
After heat pressing a transfer, the best washability is achieved 24hrs after heat application. This gives the glue time to completely bond and harden, so if doing any wash testing of a new transfer or garment, make sure to give the transfer a chance to completely bond and wait overnight before giving it the almighty wash test.
NOTE: i would never expect a transfer applied correctly to wash off if washed straight after application, however if you're wanting to know true washability and going to perform say 20-30 wash tests, best to understand the above before starting that process.
TIP 10: Your press, your fabric, your transfer, your day.
Any transfer application guide is simply that, a guide and not a range of perfect working settings. Through practice and acknowledging the details above, you'll find that heat press settings and method can change from one job to the next, or it simply could be the morning to afternoon outside temperature that can have an effect.
Don't set and forget your heat press. Heat transfer is a form of garment printing, just as technical as screen printing or embroidery. It's a beautiful art and trade that can turn ordinary garments into bright and wonderful loveables. It's easy to learn and master, with basic thought and appreciation that it has many variables and a print trade all of it's own.