Direct Color Systems DCS 1800 BG - Clear ink looks yellow/brown

[chevrolet]

We purchased a Direct Color Systems DCS1800BG a couple of years ago.

We recently had an order for a batch of ADA signs. The braille dots were spec'd as clear and the back side of the acrylic was to be painted white. We've printed ADA signs in the past but had not printed clear braille for some time. This time, the braille dots did not print perfectly clear. They had a yellow/brown look to them that was amplified by the white background.
We logged a call and was told to check the clear ink's date code. The ink was 5-6 months past DCS's recommended life. We disposed of the ink, purged the system and installed new ink.
Same problem.
We do not think we were printing yellow/brown dots using the ink that came with the system many months back.
Our DCS Support Ticket has been closed. DCS was unable to help. They checked with the ink manufacturer, who said the ink was unchanged. The DCS rep said, yes the clear does have that look but some of the discoloration will go away with time. Unfortunately, this is not an explanation I want to relay to my customer.

Anyone have a source for third party inks?

 

[CanuckSigns]

if the background is white, can you not print the braille the same shade of white for a "clear" look?

 

[chevrolet]

Good solution.
However, we are going to have to stick to clear. Clear is spec'd and they've recently bought into clear printed beads in place of clear raster beads.

 

[TEN]

We have a DCS 7200. Clear braille when printed normally has a slight amber color discoloration, it is clear-ish, but not crystal clear. This clears to nearly crystal clear after about 2 days. I did not believe it either until I saw it for myself. On our machine there are two clear channels, one shares a two color-channel damper with yellow and the other with black. 3 or 4 times a year or so we start seeing either clear braille that has a distinct yellowish tint or clear braille that has a slight blackish tint. There are longevity issues between certain plastics used in the machine and this ink set. The dampers start leaking internally and allowing the yellow or black to pollute the clear as it is being printed. We replace those dampers and it clears up.

 

[CanuckSigns]

I'm curious, how long does it take to print the braille? We use the raster method and I always assumed the printed braille was a very slow process. Also how is adhesion? Can the beads be picked off easily?

 

[netsol]

chevrolet,
is it not an issue of older in still in the lines, after changing the cartridge or whatever the ink come in?
if we had "bad" or outdated ink (where it was actually visible, i would think we Wold do some sort of ink fill routine, a flush or print so many square ft to get the old ink out of the lines and past our dampers. i realize this is different equipment /technology but the principle is the same, i think

 

[TEN]

I'm curious, how long does it take to print the braille? We use the raster method and I always assumed the printed braille was a very slow process. Also how is adhesion? Can the beads be picked off easily?

We used the raster method before the DCS printer. A Xenetech rotary engraver drilled the holes for the beads and raster beads were inserted by hand with the braille pen. Raised pictograms and text were laser cut from 1/32" Rowmark and applied by hand. With the DCS we print all of the braille and tactile elements and have the capability to add other design elements to the sign. ADA signage varies but for a 6" x 8" sized ADA sign our process is, any flat printed colors on the face would be printed first, a second file is created and printed for the braille, clear or colored and a separate file is created and printed for the raised elements. Our 7200 has a bed size of 23.8" x 48". Most often we are only printing braille and tactile features onto colored Rowmark material. I'm 'estimating' the braille pass would take about 30 ish minutes on a full bed and the tactile pass would take about 75 ish minutes. Print time varies depending on what is being printed. We have found that adhesion is very good on Rowmark and Duets materials. Acrylics vary and most require adhesion promotor. Even a material like Optix DA we would most likely use a promotor. Braille printed on Rowmark material would take a very determined fingernail to pick off. Adhesion on clear coated brushed aluminum with promotor is very, very good.

 

[chevrolet]

Sorry for the delayed response, I must not have linked activity to my email properly.

CanuckSigns - We bought the machine to see how it would work to supplement or replace work we were doing on the 4'x8' MultiCam raster process.
We can only print 3 signs (8" x 8", spec'd size) at a time on the DCS 1800 machine. Depending on the content of the tactile/braille signs, 45 minutes to an hour for the 3 signs.

NetSol - We were careful to follow the manufacture's procedure for purging the lines. The 'old' ink was not the problem. Just a victim of trying to find the problem.
DCS states the inks are viable for 12 months from Date of Manufacture.

Ten - We did a lot of experimenting to see what type of materials had the best adhesion. We also experimented with adhesion promoter and mixture strengths.
Not too much luck with the promoter. At low mixture strengths it did not seem to help and at high mixture strengths it caused problems with the appearance of the surface.
We have good adhesion with no promoter on Optix non-glare.

Thank you for your responses.