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leethesign
08-08-2010, 06:42 AM
Mornin' all.......now here's a question for the techies. I've been pondering this for ages and the more I think about it, the more confused I get and the more my brain 'urts.

I'm getting varying results from my mug press, ranging from "That's O.K." to "Another one for the bin" and I think one of the problems is controlling the time/temp.

Can anyone tell me - when the press reaches temperatur and the mug is put in to cook is the press intended to hold that temperature for the cooking time, or is it designed to cook as the press cools?

My press goes up to about 220º and then the temperature startsto drop until it reaches 140º, when it then starts to heat again.
The only control I have on it is a timer - there's no way of adjusting the temp.

The answer is probably soooooo obvious, but I seem to be having several senior moments - the sun must have cooked my brain!

I'll go and lie down in a darkened room for a while - if anyone can answer this I'd be extremely grateful........

bms
08-08-2010, 08:52 AM
I presume the press temp drops to 140 (from 220) when you put in a new mug to print? Can't think why it would drop otherwise.

This would probably be normal (although it is a long drop). The temp drops because the blanket is hot and the new mug is cold, so the heat needs to transfer to the ceramic and at the same time the press starts to heat the blanket again. 220, though, is too high a temp.

You need around 3 minutes at the normal temp of 180/190 degrees. Too hot a temp will cause the colours to darken a little as will excessive time.

If you can't control the temp then this may be awkward. I'd try 3.5 minutes from the time you put the mug into the press. That way you should get a reasonable transfer - if the press is getting up to 180 degrees in around 30 - 45 seconds from when you put the mug in and the temp drops. How long are you pressing for at the moment?

leethesign
08-08-2010, 09:02 AM
Thanks for the reply Martin,

I'm just off to my other day job at the mo - (I'm a Sunday a.m. DJ on a local radio station 9.00 - 11.00 your time) - I'll reply in full when I get back, but if I remember correctly, the press takes about 4 minutes to heat up from cold. I'll put it on and time it. Once again, from memory, if I put the timer on from a cold start for 180 secs, the press only gets up to about 160º. Anyway, I'll run the tests later this a.m. and get back to you again. Cheers again.

If you fancy listening in it's an internet based station called "Radio Baywatch" and it's at:

http://www.baywatchonline.org

and there's a link to the radio from there. I'll play yer a request!

John G
08-08-2010, 11:54 AM
If your blanket is dropping in temp because of cold mugs - warm the mugs beforehand. I do this at winter times as my unit doesn't have any heating so the mugs are freezing cold and the press really drops down when putting a freezing cold mug in.

A little blow heater pointing towards a few mugs at a time brings them upto to temp in no time - pop a warm mug into the press and it won't drop so much in temp. This works aslong as your press isn't designed to drop in temp. Another solution would be to skip the press and buy a new one :D

Cheers John

leethesign
08-08-2010, 12:51 PM
Hi John,

The last thing we're worrying about is cold mugs - the temperature in the workshop is nearly 40ºC at the moment!

The main question still is: is the press meant to hold the temp at 190 or whatever for the cookng period or is it meant to cook whilst the temp is dropping - provided it doesn't drop too much.

I've just checked again and when it's at 190ª I put a mug in and then the temp starts to drop....to about 135ª and then starts to go up again. By the time 3 mins are up,it's back to nearly 190ª. Does this seem to be normal behaviour?

John G
08-08-2010, 01:12 PM
As explained in previous post - you mug press temp will naturally drop in temp when putting in a mug as the mug is at room temp and the press is at 190 degrees. I only warm my mugs in winter but a few peeps on here say this isn't needed.

My press drops down too - this is until the mug gets up to temp.

Cheers john

Justin
08-08-2010, 03:17 PM
Just for a comparison. My press is set at 185c, when I put a mug in it drops to 150c and then takes around 80 seconds to get back up to 185c. After 180 seconds it's cooked fine ;)

leethesign
08-08-2010, 03:32 PM
Thanks guys - all clear now. I had too much information to start with....

I've done one using your guidelines and it all seems o.k. now.....thanks all for your advice.

If this mug press doesn't get it's act in order and start working properly I'm going to ask for my tenner back! :lol:

busybusybee
21-09-2010, 02:48 AM
Im having this same issue, idle temp of 90 cook temp of 180, machine bleeps when at 90, i put mug in i press go, up to 180 then 180 second timer, cup comes out too dark,if i try putting the mug in directly at 180 then press go for 180 seconds i get a drop in temp then it builds up then it cools down, the cup comes out not as dark as before but still dark, any ideas? cheer's.

Andrew
21-09-2010, 10:13 AM
When you say to dark are you meaming scorched? If the mug goes in when the press is at 180c then 180secs should be roughly correct. I tend to do 190c myself but all these things are trial and error. Whichever way you do it the mug needs to be under full heat for about 90 secs if that makes sense.