what press are you using?
whose mugs are you using?
where did you buy your kit from?
I am hoping that the answer to the above 3 questions isn't ebay, ebay and ebay
If the transfer paper isn't taped in position really tight to ensure 100% contact you will get blurring and if they are cheap mugs they may not be completely straight sided or they may have flat spots on the circumference which again means you don't get 100% contact = blurring. The coating could be uneven - the odd thick patch can cause problems as can a thin patch. It is just possible that your press doesn't apply even pressure all over the mug especially if it is a £50 ebay special. Its hard to quantify how much pressure you need to apply and if you are using cheap mugs you will almost certainly need to adjust the pressure for each mug - drop the mug in pull the tensioning lever/handle over if its much harder than normal, release the tensioning lever and knock the pressure control (usually a nut of some kind) back half a turn. If the pressure is a bit slack give it half a turn more pressure - have a bit of a practice with a cold press so you are quick and confident at adjusting pressure on the fly. Alternatively buy good quality mugs from a supplier who will back up their products.
my process is (using a Listawood Genie press, Ricoh printer and TMT, Tru Pix or Xpres paper)
1. pre warm mug - optional but very useful, especially if printing close to base, rim and or handle, especially with black text or images and essential for full bleed top to bottom.
(
http://www.amazon.co.uk/Andrew-James-El ... teppanyaki) this seems to be the preferred method of warming mugs. Some people never pre warm some people always pre warm!
2. put mug into pre heated press for temp and time recommended by mug supplier, monitor the countdown on the timer with a stop watch (mobile phone stop watches seem to be very accurate) just because it says 180 seconds doesn't mean it actually does 180 seconds of cook time consistently! You may then need to jiggle the time to get the balance of under or over cooked.
If you have a good quality infra red spot thermometer you can try to keep an eye on the cooking temperature - put a sacrificial mug into the press, cook it, measure temp on inside wall of mug, whip it out quick and immediately measure the temperature of the element - somewhere in the middle. Cool your sacrificial mug and repeat - are the readings the same within a couple of degrees each time?
3. as soon as the time is up remove mug and immediately remove transfer paper
Its up to you whether you dunk, stand mug in front of a fan or just leave it to cool at room temp. Just make sure that you don't have your cooling mugs any closer than an inch apart. I find sitting them on top of my metal filing cabinet works a treat! If I am printing a one off that needs to be boxed and out in double quick time - customer waiting usually, then it gets a very quick, naked, dunk, quick visual inspection, quick wipe with a cloth to dry it, in the bag, in the box and its gone. The secret to peeling the transfer straight from the press whilst its still hot is to grow the nails on your first two finger a bit longer so you can pick the edge of the tape off easily without scorching the end of your finger ;o) Again its one of those things that takes a bit of practice (and a few burnt fingers) to get confident with.
Never come across anyone dunking with the paper still on as Nik suggested but if it works for him, then why not. I would have thought it might be a bit messy with bits of wet paper everywhere. The thing to remember is that ideally you want that paper off as soon as the mug comes out of the press so that the transfer process is stopped in its tracks - no ink being trapped in the upper surface of the mugs polyester coating as it cools and the surface closes up.
The important thing with sublimation is consistency. The variables of time, temp and pressure need to be kept consistent - near enough very often isn't good enough and use quality stock - there is a reason those mugs on ebay are 40 or 50p each in case quantities!
regards
Arthur
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