Using iStenopad overlay as a mold

[Mirabai Knight]

Does anyone here have experience making things with silicone molds?
We've been talking about how replacement steno keys are egregiously
expensive ($7 per key!), but I know that many people would like to
make custom steno keytoppers for their n-key rollover qwerty
keyboards. I'm wondering -- if I somehow lubricate my iStenopad
overlay (http://www.istenopad.com/overlay.asp) and then fill the wells
with some sort of liquid medium that hardens and cures on exposure to
air, could that be an easy and economical way of making new steno keys
for use in custom keytoppers? I paid $45 for the damn thing (plus $10
shipping) and it's a completely failure when used as intended
(http://plover.stenoknight.com/2012/02/istenopad-overlay-bust.html),
but I'd like to get some use out of it if possible. If this turns out
to be fairly cheap and non-labor-intensive, I could make a few hundred
keytoppers and sell them to Plover users at a low cost, with maybe an
extra dollar added to funnel into Plover development. What do you
think? Anyone have any ideas on what fill material and lubricant to
use?

[Tcepsa]

For the medium to make the keys out of, there are some acrylic epoxy
options which I don't know much about, but apparently it's a two part
mixture where you combine the two and then have a certain amount of
time before it cures during which you can pour it into a mold of some
kind. It generally cures into a hard plastic, though I'd imagine you
can get softer varieties. The biggest catch is that I'm not sure how
easy it would be to get it out of the mold, but the keys of the mold
look shallow enough (and flexible enough) that you could probably just
pop them out.

Alternately, if something a little squishier would be acceptable, you
could try Sugru ( http://sugru.com/about/ ) or its DIY alternative,
Oogoo ( http://www.instructables.com/id/How-To-Make-Your-Own-Sugru-Substitute/
) which is basically just silicone caulk and corn starch. It seems
like those would be more amenable to being pried out of a mold after
they'd cured. That having been said, there may be a hazard in trying
to make silicone keys with a silicone mold. I seem to recall hearing
somewhere that you run the risk of fusing them together (something to
do with them both being silicone) but I could be completely wrong.
Maybe try just a little bit on an unimportant corner to make sure
nothing untoward happens first?

All that aside, how do you see these working as keytoppers for an n-
rollover keyboard? Standard steno keys look like they're rather
larger than regular qwerty keys, so if you just set the steno keys on
top of the qwerty keys it seems like you'd have issues with multiple
(undesired) simultaneous keypresses, and also you might not be able to
get all of the steno keys onto the keyboard in an appropriate layout.

Finally, I'm interested in a set of these if you end up making them,
since I'm planning on trying to build my own steno keyboard and had
been wondering what I'd do about the keys. (If you don't end up
making them, I'll probably try to do it myself freehand ^_^ )

[Mirabai Knight]

Looks like these are recommended for silicone molds:

http://www.sunbeltmaterials.com/por_a_kast_chart.htm
http://www.sunbeltmaterials.com/mold_release_agents_chart.htm

I figure once we've got the keytoppers we can just affix them to our
qwerty keyboards with heavy-duty mounting foam, just like Abigail's
famous stenohack:
http://plover.stenoknight.com/2010/04/abigails-brilliant-stenohack.html

[Tony Wright]

I have cast steno keys (just as an experiment) out of this:

http://jbweld.net/products/jbweld.php
(JB Weld)

Using this to make the mold:

http://shop.hobbylobby.com/products/amazing-mold-putty-698290/
(Amazing Mold Putty).

I mixed up Amazing Mold Putty and formed it over an upper and lower
key of my old, antique manual writer. Once it firmed up, I removed the
mold (it's highly flexible but durable once hardened, like rubber).

Then I mixed up JB Weld and poured it into the molds I made. A few
hours later, out came beautiful steno keys you would have thought came
from an old writer. JB Weld sets up into a material that feels more
like stone, actually, than plastic. It's hard as hell.

You could also pour that casting acrylic that Tcepsa was mentioning
into the same kind of mold. It would definitely be more cost effective
for a large run of keys than JB Weld.

--Tony

[Margaret Synnott]

I would definitely be interested in buying some of these. Is it time
for a Plover Store? :)

Mags