Why is my Stamp solid?

This is the most common problem of all and there are two causes; too much light in the manufacturing process or your artwork is letting light through.

To find out which problem it is, use the negative supplied with the kit (which is guaranteed to be black).  If this makes you a perfect stamp then your negative was at fault, if this stamp is solid as well, then your process is at fault.

1. Negative problems- there are three simple checks to find out where your problem lies:

i. Did you send a Black and White file to be printed as opposed to greyscale or colour file?
Printing is a binary process, it will either drop ink down or not, you should make the distinction of whether it will print or not, be clear. To do this select a black and white file, if you choose a greyscale file for the negative the light will decide which parts to fill in and which to leave liquid.

ii. Did the printer print in Black and White as opposed to Colour?
If you have printed in black not colour the black ink will stop more light, colour or worse of all greyscale will let more light through. In some cases the CMY black will stop more ink than the Black ink in UV exposure units, you should experiment to see which of the two is better. It also worth checking that your black ink is not empty (printers will default to print in colour if the black is empty). Check your printer head is not blocked (usually you see white lines running horizontally). If you are using a laser printer check the artwork looks black not grey, your printer may not be delivering enough toner, try to enhance with white spirit and a hot air gun.

iii. Have you blacked off the area around small negatives?
It is good plate making practice to always cover the bed of your exposure unit with black, either negative or solid black. We recommend that you use strips of black card or old negative to surround your negative. This will maintain the exposure times whatever the size of imagepac or negative. If you don’t do this and you use very small imagepac you will get more light coming round the sides of the negative and bouncing back in your exposure unit and filling in the floor- so there will be less plate relief.

2. Process errors:
This can be that your first or second exposure time is too long, the first one is the most critical as the whole of the imagepac is open to the light. Ensure that you have positioned the negative at the bottom on the first cycle and at the top on the second cycle. Make sure that you do not delay in washing it out as light can easily polymerise a half exposed and active imagepac, after washing it out you can pause as there is no time issue any more!