On 10/8/2011 12:03 PM, Richard wrote:
On 10/7/2011 10:46 PM, DougC wrote:
Eventually I got a 2' x 4' piece.
But not before ordering another one from somewhere else, so soon I'll
have two.
Oh well, I'll use both eventually.



What I need to do is transfer a pattern to the acetal for engraving it
by hand, using a dremel router with a 1/16" mill bit. CNC engraving is
not financially practical here--and for the patterns I need, a stencil
will not work.

I had assumed on getting full-size pieces of adhesive paper, inkjet
printing the patters on them and sticking them on. Cutting right through
them, then peeling off the pieces. Is there a better way? My concern
here is that the adhesive paper might stick too well to the acetal.

I know that heating adhesive-back labels with a heat gun helps them peel
off easily, but the acetal is thermoplastic itself. There's also
solvents that weaken the glue, but they also might harm the acetal.




I also have to buy a home-PC printer for this. I had assumed it'd be an
inkjet, as they print on the widest variety of materials. The higher
cost-per-page of an inkjet is not really a concern here. If there's a
better method involving a laser printer instead feel free to say.

I use my HP laser printer to make printed cutout patterns on balsa
sheets for my little airplane projects. The latest cook-up is for
rubber powered jets. A few of the guys are actually building rubber
powered fan jets (!) but I copped out with a replaceable nose plug, one
with a prop, one for show, on my peanut (13" wingspan) 707.

While working up the plans for that and a Constellation, I found that
the toner on a printed page transfers very nicely with acetone or
lacquer thinner. At least to balsa sheet.
I just taped it down so it couldn't move and do a quick wet wipe.

No idea how that would work on acetal. But if it can stand up to a short
exposure to solvents, it's not hard to test.

I had also read that an iron could transfer inkjet ink somewhat off a
regular printed page onto other materials--but the ironing time was a
big long--5-7 minutes--and I think the acetal itself would be at risk
for damage from that.

Sinkscreening would work but would be a whole 'nother mess on its own.

"Asking the manufacturer" would probably get me a referral to a place
that sells $20,000 4' x 8' flatbed inkjet printers that can print
directly onto the sheet.

It looks like the easiest way is just printing on the full-page decal
sheets and sticking them on. I was concerned about the paper tearing
into shreds during removal, but the stick-on label that came on the
sheet seemed to peel off pretty easily & cleanly.

There is also clear sticker "paper" (plastic really) that would likely
not tear as easily, but then it would also be harder to make sure it was
all removed, just because it would be more difficult to see.