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Daveb
27-05-2011, 01:21 PM
Hi!

I'm printing some mugs with a black ring around the top and bottom of the mug, and a couple of images and some text in the centre.

I've backed the rings away from the edges as I was getting fading on some of the prints. Got to the point where the print was coming out clear and sharp. Went for a celebratory cup of tea, and when I came back noticed that there was a tiny bit of bleeding on 1 or 2 parts of the rings, and on 1 mug some very slight bleeding on the text. It is just a tinge, and it doesn't show up on photo, but it is noticeable in real life.

Could it be because I am not pressing for the right time - too short or too long?

Should I be cooling the mugs in water as soon as I remove the paper?

With the mug press, should I let the temperature drop to the resting temperature before putting in the next mug?

All advice welcome!

Dave

NASH
27-05-2011, 01:32 PM
dunk the mugs as soon as they come out of the press in luke warm water

Daveb
27-05-2011, 02:12 PM
dunk the mugs as soon as they come out of the press in luke warm water
Nash,

Good news, bad news. The ring didn't bleed, but the mug cracked :D

My water was the warmer side of luke warm, so I'm not sure why that happened.

I noticed that the bleed area is more or less in the same place each time. I'm thinking it might be a cool spot on the wrap. I've lowered the hight of the mug in the press, and moved the handle as far to the the right as I can, I'm going to try upping the pressure a bit, and extending the press time.

What do you think?

Dave

Lee
27-05-2011, 02:16 PM
I always dunk with the paper attached for 20 secs or so straight after pressing, never had a cracked one yet, so not sure what could have caused that - perhaps you using too much pressure, but Im sure one of the 'oldies' will know '-)... The dunking or cooling down should stop any bleeding though...

Paul
27-05-2011, 02:25 PM
if you dunk your mugs you will in 99% have some crack ones ;) sometimes they dont crack just like that. Sometimes you can hear funny sound like a "ping" this is cracking inside the mug. So mug dont actualy need to falling in bits.

Dave, Do you taking paper of stright after mug is out of the press?

NASH
27-05-2011, 02:40 PM
Dave i press for 180 seconds at 180* whip the paper straight away and dunk in luke warm water and i`ve never had a cracked mug, but i must say i use mugs from BMS. Could it be the mugs rather than what you are doing?

Daveb
27-05-2011, 02:45 PM
I always dunk with the paper attached for 20 secs or so straight after pressing, never had a cracked one yet, so not sure what could have caused that - perhaps you using too much pressure, but Im sure one of the 'oldies' will know '-)... The dunking or cooling down should stop any bleeding though...
Nash,
Dropped the pressure a little, but also dunked with the paper still on. It gave me a good result, now to do a few more to check that it wasn't a flook!
Dave

Daveb
27-05-2011, 02:50 PM
if you dunk your mugs you will in 99% have some crack ones ;) sometimes they dont crack just like that. Sometimes you can hear funny sound like a "ping" this is cracking inside the mug. So mug dont actualy need to falling in bits.

Dave, Do you taking paper of stright after mug is out of the press?
Paul,
Usually I do take the paper off straight away and don't dunk. Really I am just trying to overcome the black ring bleeding slightly as the mug cools - could too much pressure be causing this?
Dave

Daveb
27-05-2011, 02:56 PM
Dave i press for 180 seconds at 180* whip the paper straight away and dunk in luke warm water and i`ve never had a cracked mug, but i must say i use mugs from BMS. Could it be the mugs rather than what you are doing?
Nash,
My mugs aren't from BMS - but my next ones will be.
I had raised a query on here before as to how much variation in a batch of mugs was to be expected. I've noticed that the pressure can vary noticeably between mugs, because of the slight variations in diameter. Also, when I touch 2 mugs side by side, I can see gaps and bumps of up to 1mm between them - slightly more at the top and base. The sides are slightly waved instead of straight. Is this reasonable?
Dave

John G
27-05-2011, 04:30 PM
Where your mugs from?

I don't dunk - I put a fan on the work bench set to cool and just place the mug in front of it after taking the paper off. By the time the next mug is ready the first ones cold.

I used to dunk but as Paul said, they ping a little - and that cannot be good for the mug.

Paul
27-05-2011, 05:00 PM
I used to dunk but as Paul said, they ping a little - and that cannot be good for the mug.

and it can not be good for the person who got hot tea in it :) if fall in bits in somone elese hands :)

Daveb
27-05-2011, 05:05 PM
Where your mugs from?

I don't dunk - I put a fan on the work bench set to cool and just place the mug in front of it after taking the paper off. By the time the next mug is ready the first ones cold.

I used to dunk but as Paul said, they ping a little - and that cannot be good for the mug.
John,
The mugs are my first box. I got them off eBay, from Coralgraph. I had no complaints about them to be honest, but I want to try the RN coated ones off BMS next.

I wondered whether minor variations in the mugs could have been at the back of my problems, and there seems to be an improvement now that I adjust the pressure slightly if necessary to suit the individual mug.

I'm still waiting for someone to confirm or deny that minor variations in mug dimensions are normal.

Dave

NASH
27-05-2011, 05:07 PM
and it can not be good for the person who got hot tea in it :) if fall in bits in somone elese hands :)

I`m not saying this could not happen but i`ve been doing mug for 3 years and i`ve not had one back from anyone yet.
Maybe i`m just one of those lucky ones

NASH
27-05-2011, 05:14 PM
I'm still waiting for someone to confirm or deny that minor variations in mug dimensions are normal.

Dave[/QUOTE]

The one i use from BMS always been sent to the same pressure, but i do preheat the mug on a radiator in the winter months and in the summer place them on my film processor to heat the base up

Paul
27-05-2011, 05:16 PM
Nash. I am saying IF you got that ping noize then you may have a complain. not only coz you dunk them. I did it too.


Dave. I had a mugs from coralgraph, BMS, subli-nation and some other from ebay. they all ping ;)

swimwivsquid
27-05-2011, 06:31 PM
I have always dunked my mugs in warm water and haven't had a problem. I would think that its better for the mug to break at that stage than in someones hand full of coffee. I would think its a defect in the mug or using too cold water.

Paul
27-05-2011, 06:55 PM
same here. Mate asked me to do some mugs for hos company. I dunked them as me too preffered that they brake before they live my room ;)

mrs maggot
01-06-2011, 12:32 AM
i had one bleed at the weekend, i had a good look at it, and then noticed the teflon sheet i have between the press and the mug had a crease in it - sorted.

i dunk, but will be trying the fan method, as i like the "cool idea"

Daveb
01-06-2011, 10:22 AM
i had one bleed at the weekend, i had a good look at it, and then noticed the teflon sheet i have between the press and the mug had a crease in it - sorted.

i dunk, but will be trying the fan method, as i like the "cool idea"
Mrs Maggot (really?), Interesting use of a teflon sheet. Do you tape it over the sublim sheet, or attach it in some way to the heat blanket? Dave

Daveb
01-06-2011, 10:38 AM
Nash. I am saying IF you got that ping noize then you may have a complain. not only coz you dunk them. I did it too.


Dave. I had a mugs from coralgraph, BMS, subli-nation and some other from ebay. they all ping ;)
Paul,
My only 2 experiences with dunking were, first one, after removing sheets, put mug in fairly hot water (say 50C) and it cracked - it didn't just ping, you could see the crack afterwards. Second one, without removing sheets, made a hissing noise, didn't crack or ping, but the sublim sheet stuck to the mug - maybe I dunked too long 20 secs? In both cases, the mug was completely submersed.

To be honest, unless it is an integral part of the process, I would rather skip the dunking - anybody out there a confirmed non-dunker?

Wiith dunking the amount of fast heat drop, from +180C straight into water between maybe 20C to 50C, is a large drop. The sudden temperature change causes the fast contraction that causes the pinging and even cracking. In normal use, boiling water is only 100C so you just don't get that same amount of change.

As I understand it, the idea behind dunking is to stop any further sublimation by dropping the mug temp down below the temp required for sublimation to happen. Maybe if I set my press to a lower temperature, it would cool naturally below the sublim temperature just by standing on a tray? Does anyone know the sublim temperature, and/or a reliable way of checking the press temperature? According to my settings, I am pressing at 185C - I'm thinking I will drop the temperature when I do my next batch, maybe in 5C steps, down to say 170C.

Dave

mrs maggot
01-06-2011, 10:38 AM
its a small bit, which just sits inside the mug press, its in my old press which had quite a mucky blanket when i bought it, i think the person who had it before had put paper the wrong way round a few times, i did not want any marks on the mugs - so i just cut a small bit to fit inside the press

Daveb
01-06-2011, 10:50 AM
Laura (just noticed your tag),

I'm quite keen on this teflon tip, cutting plain paper and taping it around the mug is a bit of the process I wouldn't miss!

Do you just leave it loose inside the blanket, stick it down in some way?

Dave

mgibbs
01-06-2011, 11:41 AM
Subli-Nation used to sell pre-cut paper in packs of 1000 for wrapping round the mug or putting inside the wrap.

An extra cost but quite labour saving.

Not seen them since they folded though (no pun intended) :)

Mark

John G
01-06-2011, 11:45 AM
The Ricoh printers mustn't put as much ink down as the Epsons as I've never had the need to use paper to protect the mug blanket - it never bleeds through!

Kaz
01-06-2011, 12:19 PM
Neither does mine John.

NASH
01-06-2011, 02:48 PM
Thats strange i have an epson and mine never bleeds through

Lee
01-06-2011, 04:10 PM
Ditto...........

mrs maggot
02-06-2011, 10:53 AM
as i said, this press was 2nd hand when i had it, and its very dirty, however the teflon inner sleeve works, as did not know how to clean the pad otherwise. Dave it just sits inside, i dont attach it to the mug, it just sits between the press and the mug - tbh i probably dont need it anymore, but its just in there now lol

Daveb
02-06-2011, 12:31 PM
as i said, this press was 2nd hand when i had it, and its very dirty, however the teflon inner sleeve works, as did not know how to clean the pad otherwise. Dave it just sits inside, i dont attach it to the mug, it just sits between the press and the mug - tbh i probably dont need it anymore, but its just in there now lol
Laura,

Many thanks I will give it a try. I use ordinary copy paper at the moment, cut and taped outside the subli paper. This will save me the cutting and taping.

I have noticed a feint image on the copy paper when removing it, so I guess that would have gone onto the blanket otherwise. The teflon will save that, and some time.

Dave

Daveb
02-06-2011, 12:39 PM
Might be a bit late in this thread to query definitions, but ......

When I said "image bleeding" at the start of this thread, I meant the image that had been transferred onto the mug looked like it had bled (like the ink had run a little) in one or two places on the mug itself. Is this correctly called 'bleeding'?

When the image/ink comes through the subli paper and out towards the blanket, is that called 'blowing' or 'bleeding'?

Well, I am new to this ;o)

Dave