# Using a "home" size convection oven for mug sublimation



## eagleact

Does any use a regular home size convection oven for mug sublimation? I bought the largest convection oven I could find around here. It worked ok. It seems thought the mugs in the front did not sublimate as well as the mugs in the back. It is my speculation the oven does not have good enough air flow. Also our vendor said we should only have to add a minute or two to go from one mug to 6. We found we had to almost double our time.

I also need to find a way to produce mugs in a more efficient manner. So l am planning on buying a home size oven to put in my office for sublimation. No I will not let any one use it for food!

Can any one recommend what it time and temp if I buy enough wraps for say 12-20 mugs at a time?
Or any other guidance if you have used a home oven?

Thanks.
Brent


----------



## bratdawg

Unless you are going to have help unwrapping mugs, I wouldn't suggest doing that many at a time unless you're using a conveyor oven. otherwise you may still see a difference between the first one unwrapped and the last. That being said, there are many counter top convection ovens that do mugs very nicely.

While you do need to increase the time for multiples (generally 30 seconds a mug or so), you also need to be able to maintain a steady temperature. Just like knowing what temp your flat press is really at, you need to to do the same with the oven. Oven thermometers are easily available and not expensive.

Hamilton Beach makes a "pizza" convection oven for just under $100 that works very well with 4 to 5 mugs at a time. One thing to help retain heat, particularly when the door is opened is to use a pizza stone on the bottom. Also, remember to allow some room between the mugs and the oven walls to allow the air to circulate and place your mugs upside down.

HTH. Good luck.

Steve


----------



## eagleact

We need more volume than the little ovens provide.
The only conveyor heater I have found is is a huge investment. Hix makes ones that is around $17000 with the cooling tower.
Looking for something in between!
Thanks.
Brent


----------



## mgparrish

eagleact said:


> We need more volume than the little ovens provide.
> The only conveyor heater I have found is is a huge investment. Hix makes ones that is around $17000 with the cooling tower.
> Looking for something in between!
> Thanks.
> Brent


Brent,

Might look into the larger microwaves that are combo units ... microwave and convection oven combo. Of course we don't _microwave_ the mugs, but the more higher up models include traditional convection heating.

I have a Daewoo combo unit that I got years ago and holds five mugs at a time and has the advantage of full digital control and a rotating carousel which helped keep the mugs heating consistant no matter where I located the mug.

As Bratdawg mentioned variances in mugs will be presented if doing too many mugs at a time so perhaps you can find a few combo units that are larger than "toaster ovens" but not as big as a full oven. 

Then scale your production into a few of these ovens being careful to "stagger" the loading of them in the seperate ovens so that not all the mugs are completed simultaneously, or have more than one operator so you can tend to multiple ovens concurrently.


----------



## eagleact

Interesting. I like the rotation. I think that would help tremendously.
Thanks!


----------



## jleaspencer

I have a question it might not go with this topic or does, but when putting the sublimation image onto the mug or a dog bowl or any product that can be used, do we need mug wrap or can i just use heat tape to keep it in place on the product.. what i am saying what is the wrap really for? Are they to keep the paper from burning, or just extra pressure... and can i use just heat tape without a mug wrap or any wraps..


----------



## mgparrish

jleaspencer said:


> I have a question it might not go with this topic or does, but when putting the sublimation image onto the mug or a dog bowl or any product that can be used, do we need mug wrap or can i just use heat tape to keep it in place on the product.. what i am saying what is the wrap really for? Are they to keep the paper from burning, or just extra pressure... and can i use just heat tape without a mug wrap or any wraps..


You should use a wrap.


----------



## freebird1963

mgparrish said:


> You should use a wrap.


I have been wondering this too. So why ? Have you tried any w/o the wrap ? I don't have any sub mugs otherwise I would. 
I'm curious more than anything.


----------



## STPG Press

Because, PRESSURE.

The wrap puts a certain amount of pressure across the transfer paper. You can't do that with tape.


----------



## mgparrish

STPG Press said:


> Because, PRESSURE.
> 
> The wrap puts a certain amount of pressure across the transfer paper. You can't do that with tape.


Agreed.

Another point would be that surface is not a perfect sphere, there is always some irregularity, so just taping might not be tight in those "void" areas or less than perfect curved surfaces. So the transfer is not tight or maybe even touching in all places.


----------



## freebird1963

I know voids and pressure and all that the question was about TRYING it and seeing if it really made a difference and if so how much,
not the theory that we are all told when we get into sublimation. 
I have yet to find one article or KB that states the amount of pressure needed, like 1lb 5 lbs or 1000lbs of pressure or torque.
So do you really know or regurgitating the info of what we all been told.?

What we are normally told is EVEN pressure not HOW MUCH pressure.

Lets look at some people doing shirts who say the lay the press lightly on them when pressing. Not much pressure there is there. ? 

So how much pressure is ACTUALLY needed ? 

If I had any coated mugs I'd try but all I have are uncoated at this time.


----------



## STPG Press

I know where there is a full warehouse of blank mugs. Order tonight and you can have them on your doorstep within days. Try it and report back to us. 

Only thing I can tell you is to try. We can theorize about it, ponder it, even argue about it. We generally know what the best practices are for almost any sublimation process. Sometimes we vary them, but seldom do we stray far away from them.

Who knows, you might be the next great Sublimation Whisperer. 

Cheers!


----------



## freebird1963

Whos we ? You and the shadow ? I do know the shadow knows but not sure about you . 

If I only needed mugs today so I could get them in a few days. So sad, Oh well another ship has sailed in the night without me on it. 

In theory a bumble bee and helicopter can't fly did you know that. Guess good thing some folks aren't engineers or inventors 

Thanks
Living outside the box


----------



## mgparrish

freebird1963 said:


> I know voids and pressure and all that the question was about TRYING it and seeing if it really made a difference and if so how much,
> not the theory that we are all told when we get into sublimation.
> I have yet to find one article or KB that states the amount of pressure needed, like 1lb 5 lbs or 1000lbs of pressure or torque.
> So do you really know or regurgitating the info of what we all been told.?
> 
> What we are normally told is EVEN pressure not HOW MUCH pressure.
> 
> Lets look at some people doing shirts who say the lay the press lightly on them when pressing. Not much pressure there is there. ?
> 
> So how much pressure is ACTUALLY needed ?
> 
> If I had any coated mugs I'd try but all I have are uncoated at this time.


So I would say that it's not the act of pressing hard into the coating, it's a matter of enough pressure to get the paper covering the surface as evenly and completely as possible. By the way I am an Engineer, here's a concept that will blow your mind and it's well proven ... nothing actually really "touches" 

I don't think much pressure is needed, but there has to be enough to adequately make sure the paper "forms" to the substrate.

When I do tiles in order not to crack them there is very little pressure. My nomex felt is very soft, just soft enough to allow the paper to "form" into the bevels.

But on a wrap that material is semi-rigid so I think the pressure is really a question of getting the wrap material to conform to the surface allowing the paper to sit uniformly. 

But I think your question is academic, unless you can dampen the paper then place on the mug (which would fubar the ink) it's not going to conform on it's own just with tape. 

One possibility would be if the "tacky" paper that some use for poly material sublimation could work on the mug then perhaps it "self conforms" when heated and could fill in the irregularities. Or if the "tacky" is inherent and not activated by heat.

Ceramics really do have irregular geometry.


----------



## bratdawg

As others have mentioned, the Wrap is to provide even pressure. The general rule of thumb with the Cactus Wraps, is to finger tighten the bolt and then just another turn or so with the nut driver.

As Mick from Cactus used to say (may he rest in peace) is that you just need to have intimate contact with the transfer.


----------



## mgparrish

bratdawg said:


> As others have mentioned, the Wrap is to provide even pressure. The general rule of thumb with the Cactus Wraps, is to finger tighten the bolt and then just another turn or so with the nut driver.
> 
> As Mick from Cactus used to say (may he rest in peace) is that you just need to have intimate contact with the transfer.


Hi Steve!

To your point, it's important to follow what you mentioned otherwise the wrap life will be shortened, I know this from experience.


----------



## bratdawg

mgparrish said:


> Hi Steve!
> 
> To your point, it's important to follow what you mentioned otherwise the wrap life will be shortened, I know this from experience.


Thanks Mike, that is correct. Most think you need to tighten as much as possible, but the wrap will weaken and tear.


----------



## teodorc

@On-topic

I bought a convection oven, that heats both on top and bellow. It's one of those types that you use in the kitchen, we sometimes make frozen pizza or lasagna in it. It won't affect the mugs. It costed us about 150 USD.

The problems we found are the following:

- Different mugs, different time. Not like in the heat press where 3 minutes are ok for any mug.
- If you make the mistake to open the door you are screwed. You lose about 50 degrees Celsius on the opening.
- It's very hard to unwrap all those mugs at once. They are very hot because of the longer time they spend in the oven and even the best protection gloves will let the heat in and burn your hand.
- You have to be willing to lose about the same money you spent on the oven with mugs until you get the correct times for different quantities of mugs.

Some tips:
- Buy an oven thermometer to be sure of the temperature.
- Be careful to not overcook them because the print will transfer on the silicone wraps.
- Be sure you have enough orders to keep it running. The initial heating can take a while.

We ended up abandoning the oven because we could not get the correct settings and ended up in using more heat presses bought from china.
If you do 12 mugs in the oven, it's about 13 minutes.
With 3 heat presses you do the same amount of mugs in the same time. (3 mugs/3 min.)
But of course, it depends on the jobs. When it comes to full prints an oven may suit you better.


----------

