help with heat press problems

[davest]

Hello.

I am new to Dye sublimation, I am using a Epson WF3010, I have just tested sublimation to mugs which has turned out fine, I am having problems when I try and put an image on a tshirt, I am using Sublimation tshirts which are 100% polyester on the outside and 100% cotton on the inside, when I press the image on the Tshirt it comes out faint, I have tried a few tshirts all with the same effect, 1 of the tshirts which I was using to test images, did put a faint image first but then when I placed a new image over the top the next image was spot on, the temp on my press is set at 360 for 80sec. I have also pressed a blank jigsaw, when I first pressed it it did not work so I closed the lid again and left it for another 80sec and it turned out great, what am I doing wrong, at the moment I am just testing hoping to take things further, any help and guidance would be greatly appreciated. thankyou to anyone who can help.