# light image on ceramic mugs convection oven



## personalazeit (Nov 5, 2009)

I have a stone in my toaster oven sized convection oven. Sometimes I get good results, and sometimes the image comes out light. As of now, I owe my customer 5 mug replacements (out of 15) because the image came out light on them. I don't know at what point in the process they were getting made because I had a helper who didn't really think the image was that bad... oh well, anyway, today I went in to make 1 at a time. Usually, I only make 1 mug at a time, then I occassionally make a bunch. This isn't really a debate on a mug press vs my oven because the oven used to work so well for me, but it was the heavier duty mug wrap with the screw on thingy... then I had to switch over to the clasp style wraps that aren't as thick as the heavier screw on one. (at one point, I ordered more mug wraps and those are just what came, so that's why I have more of those now). ANYWAY... My oven seems to hover at 425, and the last mug I did was for 12 minutes. So, today, I did 1 mug for those settings... still light. SO I thought, maybe too much time, then I did one for 8... WAY too light.

I don't have a ton more mugs to waste. Anyone who is using a smaller toaster oven? Anyone using those clippy style mug wraps? What are your successful settings?

I do have a temp gauge inside the oven so I know that I am aware of the temp differences of the oven. I'm really fast and opening and closing the oven door.

I am so thankful for any input you all may have!
Thanks!
Tracey


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## personalazeit (Nov 5, 2009)

My husband is thinking that since it is really cold in my shop, about 45 - 50 degrees that the mugs are probably colder going in the oven, so ill go a bit longer and see if that helps.

12 minutes too light in splotchy areas
8 minutes way too light all around

I'll post my updates.


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## sben763 (May 17, 2009)

When I did mugs in the oven I would pre warm them with a ceramic heater. The mug should be between 70-85 before setting the transfer on mug. This was directly from the supplier


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## personalazeit (Nov 5, 2009)

Thank you sben763, I just did a prewarm, but not that hot, I hope we're onto something then! First test is in right now, except my oven was at like 375 so now I may be too hot, going for 12 min on this


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## Cracked Egg (Aug 10, 2009)

I do 400 degrees at 12 minutes in my convection oven. However, I use the screw on-type of wraps because you can control the 'tightness' when wrapping the mugs. This setting is for 15 oz mugs. I do not do any 11oz.

Your oven may be too hot.


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## personalazeit (Nov 5, 2009)

I'm trying the wrap you're talking about now, it's the only one I have and I never had these problems with that wrap. It's when I went to JDS and just ordered 10 wraps, I didn't even notice, but they shipped me those clippie style ones. I called them and asked why, they said, they discontinued the screw on ones? Anyway, I lowered my oven to 400 and am trying right now for 12 min.

As for my other 2 samples, mixed results... I have 2 sides to my mug, 1 side is a photo, the other a logo. The first test, the photo came out light, but the logo very nice... the second test, just the opposite. I really feel like the oven has inconsistent areas or these wraps are CRAP!

I've wasted 4 mugs this morning. If this test also has issues, I will just start testing on wasted mugs. Stay tuned!


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## personalazeit (Nov 5, 2009)

Now I have too many variables... I just tried the wrap with the screw on. I used to always have good results with that one, but that was when I did stuff at home in my even more unreliable oven I cook in (which I don't do anymore, I have since learned...) anway, still light. I'm attaching photos. I'll describe per pic post.

These pics is the mug I just did with the screw on wrap @400 for 12 min.

So... if I do a test mug next with only this wrap... longer or shorter on time?

Also, should I turn off the convection feature? My oven at home was not convection, is that causing the inconsistencies?


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## personalazeit (Nov 5, 2009)

I did another test... too light... I'm upping the oven temp again. It's really cold in my shop, this last mug, I watched the oven temp drop down to 375~378 for the entire 12 min, so I'm trying to find the sweet spot so when I open the door, and the mug temp being colder... it evens out to 400 for the duration of the 12 min.

I'm also thinking of turning off the convection, any thoughts on that?

When I used my oven at home, it was not convection, just bake.


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## personalazeit (Nov 5, 2009)

Just for reference purposes, here is a good logo, and a good photo, but both of these examples, the opposite of the mug is light (2 different mugs), both of these were with the silicone clip on wraps with 3 sheets of paper for insulation and bleed protection.


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## personalazeit (Nov 5, 2009)

Making a little bit of progress. I had to switch back over to the silicone snap wraps just because I have more of them and when I was using the screw on one, my results were light every time and I at least was more in the ball park with the silicone ones.

So, currently, the convection feature is off
400 degrees
14 minutes

I've done 1 minute increments from 12 to get to where it's looking good. Right now, I'm doing another test with both sides, so fingers crossed.

Also, the oven has to get about 25 degrees hotter to account for the drop in temp when I open the door. I'm starring at the temp gauge inside to try to figure out how to keep the temperature consistent.

I'll post my final settings when I'm done with all this mess!


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## personalazeit (Nov 5, 2009)

Ok, so that test looked good... doing the real thing now.


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## personalazeit (Nov 5, 2009)

No exciting news to report... the last real mug, the photo looks ok, passable, but the logo, slightly light... so next test, I'm back to 13 min.

This is extremely frustrating. I wish I knew what variable is killing me here.

It's been 7 hrs of testing, I think I'm done for now.


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## sben763 (May 17, 2009)

Is it possible the mugs you are using the problem? If the coating is uneven or not thick enough cod be the issue.


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## personalazeit (Nov 5, 2009)

That's certainly a possibility, they're from JDS and they typically have good products I thought?


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## LEO (Oct 10, 2006)

Convection oven:

*Try setting it at 425*
* Place mugs on top of oven to warm bottoms as the oven comes up to temp.
* open door quickly and place mugs with space around
* 1 mug 15 minutes
2-3 mugs 16 minutes
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I have also placed unusable ceramic tiles in bottom to hold heat.

LEO


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## personalazeit (Nov 5, 2009)

That is definitely the direction I was headed last night.

2 questions:

1. should i get rid of the stone, or place stone on the bottom of the oven? currently the stone is on the rack, and the mugs on the stone.

2. convection mode or not?


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## LEO (Oct 10, 2006)

definitely CONVECTION.

The stone may be the problem.
I didn't zero in on that in your post.
I don't know what kind of stone you are using but I use dye sub tiles which have chips etc... or broken ones.
Piled 2 deep.
Helps retain the heat so oven doesn't have to cycle quite so much.
Also have ALWAYS done 15 minutes but add a minute when doing 2-3.
LEO


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## personalazeit (Nov 5, 2009)

OK! I put the stone at the bottom of the oven below the rack, below the 2 other lower heating elements... turned the convection back on... 12 minutes! YES! I'm back in business, THANK YOU!!!


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## personalazeit (Nov 5, 2009)

oh... ALSO 425 the mugs were pre-warmed on top of the oven.


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## LEO (Oct 10, 2006)

GREAT ! 
Consider lining the bottom with tiles.
I also have 2 blank mugs upside down at the back...
one on each side...to help hold more heat.
Also 15 Min... especially if there is alot of black in the image.
LEO


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## Humerus (Nov 10, 2012)

Glad to hear you figured it out! I was thinking it might have been the stone also... Might have been an airflow issue since that's a big part of convection. I also use the clippy silicone wraps and do tons of mugs in my convection oven, don't have a stone or tiles or anything and I do 3 mugs in 10.5 minutes. The temp is correct, too, not sure why this particular oven makes 'em so fast because my old oven was at 14 mins for 3.


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## bratdawg (Jul 17, 2012)

Sorry I didn't see this sooner, but glad to see you're back on track. The pizza stone should definitely be on the bottom, with the mugs upside down on the rack. This allows the air to flow around the mug and up to the bottom. Also be sure to allow some room around each mug for the same reason. With the Cactus Wraps, we recommend 400° for about 15 minutes and increasing the time for multiple mugs.

Steve


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## syndeez (Jun 24, 2014)

I am a newbie and have learned so much just from Personalazeit's posts. I am glad to see that all worked out. I have been researching whether to get a Mugpress or Convection oven. I am liking the oven more and more as I read these threads. Bratdawg, can you please tell me the convection oven you are referring to with the pizza stone. Personalazeit, can you please show me a pic of how/where you placed the stone....TIA


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## bratdawg (Jul 17, 2012)

syndeez said:


> I am a newbie and have learned so much just from Personalazeit's posts. I am glad to see that all worked out. I have been researching whether to get a Mugpress or Convection oven. I am liking the oven more and more as I read these threads. Bratdawg, can you please tell me the convection oven you are referring to with the pizza stone. Personalazeit, can you please show me a pic of how/where you placed the stone....TIA


Hi Cynthia,

The particular convection oven we use here (though as a distributor we don't really do production) is a Hamilton Beach 12" Pizza Oven. They are usually available at Walmart, Target etc or perhaps on Amazon.

The pizza stone easily fits below the two bottom heating elements. It has enough room to do 4 or 5 mugs at a time. Feel free to contact me if can be of further help. 

Steve


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## syndeez (Jun 24, 2014)

Bratdawg.......thx so much for your quick reply. I am off searching some more about this oven. I will hold you to your word of further help (if needed) I appreciate you....thx again


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## yinzer (Nov 12, 2009)

Is this the Hamilton Beach oven you use?

Hamilton Beach Countertop Oven with Convection - Walmart.com

Or this slightly more expensive one?

Hamilton Beach Large Capacity Counter Top Oven, Black - Walmart.com

They both appear to have the same dimensions. Are they tall enough for water bottles also?

(hopefully links are permitted)


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## bratdawg (Jul 17, 2012)

Unfortunately ours does not seem to have a model number listed, but both of those are about the same size. Not sure the second one is convection, but not a problem if it maintains the heat well. The pizza stone definitely helps, but in both cases do yourself a favor and get a good oven thermometer and don't rely on the knob settings. Ours is off by a good 30 to 35 degrees!

Steve


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## Brian (May 18, 2007)

Question!! Why use a convection oven that takes 15mins. when a mug press takes 4mins? Is there an advantage?


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## mgparrish (Jul 9, 2005)

Brian said:


> Question!! Why use a convection oven that takes 15mins. when a mug press takes 4mins? Is there an advantage?


More even heating. You can also do more than one mug at a time to eliminate the time disadvantage if the oven is large enough.

Many presses "shock" the mug thermally so you have to dunk the mug in warm water to "check" the migration or might not handle some mugs very well.

I can usually get closer to the handles and/or top/bottom using wraps. I have both wraps/oven and a mug press, 2 actually. The mug press is nice at events or on demand retail for live production.


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## LikensEretailing (Mar 6, 2015)

use only one piece of cover sheet for protection


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## LikensEretailing (Mar 6, 2015)

I only cook my mugs for 11 min at 400


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## mgparrish (Jul 9, 2005)

LikensEretailing said:


> I only cook my mugs for 11 min at 400


 Cook time depends on the mug, mug size, coating type, and how many mugs being cooked at once in the oven.


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## bratdawg (Jul 17, 2012)

mgparrish said:


> Cook time depends on the mug, mug size, coating type, and how many mugs being cooked at once in the oven.


Just to add to Mike's comments, I would also suggest a good oven thermometer so you can be sure what temp your actually using. Many units are off by a considerable amount and temp will also affect time.

Steve


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## mgparrish (Jul 9, 2005)

bratdawg said:


> Just to add to Mike's comments, I would also suggest a good oven thermometer so you can be sure what temp your actually using. Many units are off by a considerable amount and temp will also affect time.
> 
> Steve


 Very good point Steve.


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