There are multiple light source units and single point light sources. Obviously, single point light sources control the light better and are advised to be used for more detailed film exposure. Multiple units scatter light and attack the films from multiple angles creating "undercutting" that reduce screen accuracy.

Both work, single source is better.

Posted in Frank Lee Blog

A tight seal between the screen, film and the exposure unit glass it critical to prevent "under-cutting". Under-cutting is when light creeps around the dark areas of the film positive and exposes the emulsion beneath it to light.

Frankly, that is complete failure to the system. Keep your blankets in great shape and achieve the best seal possible.

Posted in Frank Lee Blog

The tighter your screens are the brighter your prints will be. The tighter your screens are the less squeegee pressure is required to print properly. How much pressure do you think it takes to push ink through a screen anyway?

Tight screens improve registration by reducing or preventing "screen roll" (the pressure wave of mesh that rolls up in front of the squeegee much like a wave in the ocean), allows more ink to sit "on top" of the garment where it belongs rather than being smashed through the weave down to the platen (which helps fend off sublimation in more ways than one), reduces the need for massive squeegee pressure (which most printers apply), and finally lets you set your squeegee angle at a more proper upright position of 65 to 75 degrees allowing you to properly use the business end of the blade (the edge).

Frankly, using less expensive frames that do not achieve higher tensions (over 25 newtons) are costing you money, not saving it.

"Time is money, so don’t waste either".

Posted in Frank Lee Blog

Roller frames allow you greater control and the ability to re-tension. Aluminum frames are good and hold tension for as long as the mesh does not stretch but it eventually will and requires a stripping and re-gluing process.

Wood frames absorb water and solvents and have the lowest ability and shortest useful lifespan.

Roller frames are best.

Posted in Frank Lee Blog

There are many shapes and sizes and all are designed to "sheer" the ink from the mesh and transfer the ink to the garment. I’m not going to get too deep here as there is so much to cover and the manufacturers will send me tons of letters defending each size, shape durometer and such.

I use 70 durometer square edge squeegees with 2" or less of blade extending from the housing. Set at angles between 75 degrees and 65 degrees this does the job perfectly for textile printing. Proper screen tension (tight) and proper squeegee pressure does the job of "sheering" the ink. Do what you will, but this is how I would set up your press if I were at your place.

Take a look at high-end squeegees such as the "constant force squeegee". Its blade is so small and it’s angled at 65 degrees (close to it). Clamped into the printer at 90 degrees and the rubber is auto set to the proper print angle. Yes, I know it takes a very level platen to take advantage of this great idea (not all can), but hey, right is right and if we can’t create a perfect environment now at least we know what we are shooting for. Strive for it in every way you can but take from this information as it is intended. That crazy shaped housing is focusing the pressure down the tip of the blade where it belongs.

Frankly, the next time you see your blades doing the "limbo" on press back off the pressure as you are not helping yourself.

Posted in Frank Lee Blog