[kaneda7777]

Hi i have just read online that to properly cure a shirt in a professional way you MUST use a conveyor dryer... and not do a long flash cure...

can someone explain to me why this is so?

Whats different by using the conveyor rather than a 60 second cure on the flash dryer.

ALSO

my second question is what do i need to make my own plastisol transfers?

many many thanks everyone

PEACE

 

[RichardGreaves]

To properly cure a water base or plastisol textile ink, you need to heat the ink and shirt so they both go to 320°F. Water base takes longer because you have to evaporate all the water, (sometimes 75%), THEN heat the resin 320°F.

You've asked an equipment question, but you have to consider the variables like ink color and thickness. Anything relating to time is RELATIVE to all the variables.

Transfers
Print plastisol ink on transfer paper and only partial cure to a gel temperature of about 220°F MAXIMUM. Higher temperature and the ink will not hold on to the shirt well when you transfer.

Buy Scott Fresener's book, "How To Print T-Shirts for Fun and Profit". There is a whole chapter dedicated to it.
http://screenprinters.net/product.php?pid=b-htp

 

[kaneda7777]

so can you not do that on a flash dryer?

 

[RichardGreaves]

That's my point. Don't focus on the equipment. Any equipment, and heat source - MoM's oven, pizza oven, Black & Decker paint stripping gun, Master Appliance heat gun, flash unit, heat transfer press, hand iron - If it can get the shirt and ink up to 320°F. Check the spec on your actual ink. Every degree more is wasted, and can harm the shirt over 370°F.

Focus on the temperature.

 

[kaneda7777]

so is there any point in having a conveyor dryer then? is it just usefull for huge volume orders?

thansk again for the quick reply man

appreciated

 

[treadhead]

Yes..you can use a flash unit which is what I use.

The advantage of the conveyor is speed. But, since I only have a 1 station / 4 head machine, I rarely out pace my flash unit at the moment. My next step would probably be to add another flash unit if I added more stations. This would allow me to flash a shirt while I am printing another..which I can't do at the moment. After that, I would start thinking about a small conveyor unit.

 

[Solmu]

so is there any point in having a conveyor dryer then?

Richard laid out what you need to achieve to cure the ink.

From there it's just a matter of "Can my equipment adequately achieve this?". Or from the other direction, "I need to achieve production goal X - what equipment will accomplish this?"

In the case of some flash dryers the answer is yes, with others it's no (potential problems: cold spots, too small, too inefficient, etc.). But that's up to the individual equipment and needs at hand.

Not surprisingly, conveyor dryers are better at it than flash dryers are. They're also potentially overkill.

Richard is trying to teach you the whys and hows so you can answer your own questions. If you understand the process, you won't need to depend on other people's generalities of "flash bad, tunnel good" because you'll know what you need.

Understanding the process is far more valuable than other people giving you one size fits all answers.

One of the good things about screenprinting is that it's measurable and scientific. Empiricism takes out the guesswork.

 

[RichardGreaves]

Logic for a conveyer dryer

so is there any point in having a conveyor dryer then? is it just usefull for huge volume orders?

Speed. You drop your shirt on the belt and get back to printing. Yes, speed costs money.

Stand still, and stare at a traditional clock. 10 seconds to load and print. Now stand still for 60 seconds. Be careful. Too long and the shirt starts to burn. Not enough and the ink starts to crack on the Mayor's t-shirt after the 5th wash.

Conveyor speed can be adjusted so each shirt leaves the oven when the ink IS COMPLETELY CURED by the IR energy moving completely through the ink film to the shirt.

If you have a small budget and lots of time none of this matters. As soon as you get bored staring at the wall while you wait, you will start saving up for an oven.