Many of you have been trying out applications on all kinds of substrates which we think is awesome!
A common question we receive is how to apply on items that include “Do Not Iron” or “Cool Iron Only” on the tag.
(These tips will also work for applying on heat-sensitive fabrics like rayon, 100% polyester, silk, or any other material you’re unsure about.)

Our first piece of advice is:

1. Don’t Apply Unless You Have An Extra to Spare

If the tag specifically calls for no iron or a cool iron it’s most likely because the material will discolor under high heat. Sometimes the discoloration is temporary. Other times it’s permanent. If you have a project you really want to do and you’re willing to run the risk of irreversibly ruining the item, it’s best to have at least one duplicate item as a backup. However, if you’re in a pinch, you can test press an inconspicuous area of the garment like inside on the back.

2. Use a Heat Press

Did you know most iron settings are actually a range of temperatures? When you hear the little tick from the iron you know you’ve reached the highest temperature in your setting and it will cycle back down to the lowest temperature in the setting. For most projects, the variance in temperatures is not a problem, but when working with heat-sensitive fabrics the regulated, accurate temperature on a heat press is your best bet. Additionally, achieving proper pressure with your home iron is not as accurate as a heat-press. Proper pressure is important for every project, but especially when we’ll be reducing another part of the application process. Which brings me to tip #4!

3. HI-5 is THE material you need!

Forget all your worries and personalize your garment with HI-5. The great thing about Siser HI-5 is that it only requires 120°C and 5 seconds application giving you the perfect setting for the most common polyester-based fabric. The low temperature and the quick time prevent unpleasant glossiness effect or fiber damaging. You can choose among a captivating range of colors all VEGANOK, laboratory tested, and certified for baby clothing, home textiles, and decorative fabrics.

4. What if you don’t have HI-5 on hand?

As you know, most of our materials can be applied at a temperature of 150°C. Our heat application settings, listed on the Siser website are what we suggest for the best application, but they can be adjusted to fit your project. If you want to use a material which is not the HI-5, you can try to lower the temperature and increase the pressing time.

We take for example StripFlock® Pro: even if it typically takes 15 seconds at 155°C to be pressed, as an alternative you can press it for 25-30 seconds with a lower temperature (do not go below 140°C).

5. Use A Heat Transfer Cover

We recommend a heat transfer cover sheet when pressing heat-sensitive materials. Heat transfer cover sheets offer delicate textiles a layer of protection from the hot upper platen. If you don’t have a cover sheet you can use parchment paper or the shiny side of the multipurpose paper.