Generating tactile drawings.

[Linux for blind general discussion]

[ Sorry; hit send before I was really ready.  -r ]

Here's Wikipedia's take on swell paper, buried in a page on tactile graphics:

> Swell paper has a special coating of heat-reactive chemicals. Microcapsules
of alcohol implanted in the paper fracture when exposed to heat and make the
surface of the paper inflate. Placing black ink on the paper prior to a heat
process provides control over the raised surface areas. ...

-- https://en.wikipedia.org/wiki/Tactile_graphic

> ... how do you transfer images from the normal paper to the swell paper

I used a multifunction device (fax, printer, scanner) as a copying machine.
The reason I did this is that the ink in my normal printer smeared on the
rather slick surface of the swell paper.  I guess the ink in the copier comes
out a bit dryer...

FYI, any device used to process swell paper needs to have a reasonably
straight paper path, to reduce the risk of jamming, damaging the paper, etc.
Also, the ink needs to heat up significantly when exposed to the bright
light in the expansion unit.  Carbon-based inks seem to work well for this.

- Rich Morin