David,

I use an HP 1200 to print on the accuart2. The area surrounding the image needs to be darn near black with no light coming through.

The exposure unit I have is the Letralight (sp?) also and like UCONNDAVE said, exposrue time is 3 minutes. My rapid mask has sat in a box since the end of last October. Since I was moving I did not even bother to unpack the blaster, so shelf life is not the issue. I think maybe you just need a longer exposure time for the rapid mask.

I tried using the 2 mil and the 4 mil, neither had a blow out. I just could not get them to lay flat.

As for the adhesion, I did not use the misting methon, but that would work well for placing the image.

My wife Lisa who is much more patient than I, could not get the resist to lay flat either.

Chuck,

The black border around my image was about a quarter inch on each side. After the exposure, I cut the darker part of the border to allow for an easier removal of the carrier sheet.

Dave,

I didn't bother to change my settings because Photobrasive has recommended settings of 30-35 psi. I have my system set at 30 psi.

I also use 180 grit silicon carbide for my blasting media.

Chuck,

It wasn't me saying to use 3 min, we use 4 and it works fine. Very difficult to overexpose RapidMask.

Dave

David,

How close do you hold the nozzle from the media? You might want to try 6" and back off on the pressure.

Dave

David,
I tried blasting these with 33psi as recommended by Photobrasive. When I turned the pressure down to 27psi, I got a much nicer etch.....

Probably nothing but the standard inaccuracy of the pressure gage. Minor wear in the nozzle or venturi mixing area can make large differences also.

Philadelphia, PA (Really Bensalem)

Harvey's Sub Page When you finally understand it completely... it changes.