Frosted Mugs Craking

[Ricky]

has anyone got any tips for sublimating onto frosted mugs? i am warming the base in my heat press, and heating up to 170oc using a very light pressure.

i have successfully done 3 Mugs this morning following what i said above. i have now opened a new box of Mugs, from the same supplier and once they are in the heat press for about 60-90 seconds they crack/shatter


any help would be great. i now only have enough mugs left for what i need to do so dont really want to start changing the temperature as it worked fine before

cheers
Ricky

[James990]

Interesting, I have only ever had one crack and that was because I was stupid enough to put it down on a cccold surface, forgetting that it was still hot, instead of putting it down on the cooling place that I use.

I usually put them fully in the heat press for about 30 seconds before putting the transfer paper on and then put them back in to do the business so to speak. 180c and 180 seconds

James

[Ricky]

Hi James i have just tried it the way you suggested heating up the full mug rather than just the base and it worked!! well the 1st one has........

[Ricky]

ok two worked fine, then the third cracked again am i missing something? surly if two where fine i cant be doing anything wrong? :s

[pisquee]

Are we talking about the glass mugs here?
They usually crack because of a difference in temp between the base and the sides - they base needs to be warmed through fully to match the temp that you will be heating the sides - so don't take them out the press for the pre-press until the middle of the base feels hot, maybe even leaving them on a hot radiator, or putting them in your oven before hand would help?

[Ricky]

yeah the glass mugs. i have lowered the temperature to 160 now and warming the mug fully for 30 seconds which seems to be working