Hi!
My name is Roey, ans me and my friend are right about to finish our hardware phase in our Multitouch project.

We are currently stuck with attaching the sketch paper to the acrylic ( without having air between them when it’s flipped over..)

note that we don’t have a silicone layer on the acrylic…
any advice?

Thanks!

--

http://www.touchproject.net

hey… there is no perfect solution for this kind of application as i used a similar setup myself for my prototype… the way i did it was >> apply a layer double sided tape along the entire edge of the acrylic ... and press it hard so there is no gap for air to come in ... (dont peel off the other side of the tape now) .. now use a lint free cloth to clean / wipe the entire surface .. (make sure your surface is not kept on a table / surface that can earth it) .. idea is to have some static charge on the surface..

now if you apply your film.. due to the static it clings nicely to the surface .. now remove the paper from other side of the tape and roll the film on top ... the reason this stays is that there is almost vaccum between the film and acrylic .. and if you seal off the edges properly with double sided tape… it should remain that way ... since air wont seep in.

but gravity takes its toll sooner or later .. so if you dont plan to use your surface for a long duration then keep the surface upside down not allowing the gravity to work on your film.....

hope this helps!!!

cheers!!!

I wonder if anyone has tried using the spray contact adhesive (creates a post-it note amount of stickyness) to attach tracing paper to glass/acrylic sheets when used in a DI setup?
Going to look into getting some over the next couple of days, but if someone has tried it and it definitely doesn’t work would be good to save the trip to the shop to get it!

cheers!

I was thinking that same thing. But it might just refract IR light.

My friend and I were also thinking about an alternative to the loose sketch paper on top of that screen.

We had the idea of roughening up the top of the plate by using sandpaper. Would this be possible?

Thanks!

p.s.: we are using rear IR illumination.

Ico - 10 June 2008 03:12 PM

My friend and I were also thinking about an alternative to the loose sketch paper on top of that screen.

We had the idea of roughening up the top of the plate by using sandpaper. Would this be possible?

Thanks!

p.s.: we are using rear IR illumination.

This could work but you might be disappointed with the result for a few reasons:

1. it would be difficult to get a result that does not show the overlap of sanding
2. you might be disappointed with the viewing angle of your projection with this method, depending on how much you sanded.

I would recommend trying it on a smaller piece to see how you like the results.

Ico - 10 June 2008 03:12 PM

My friend and I were also thinking about an alternative to the loose sketch paper on top of that screen.

We had the idea of roughening up the top of the plate by using sandpaper. Would this be possible?

Thanks!

p.s.: we are using rear IR illumination.

NO! It will glow with IR refractions and be ruined.

Ok, thanks for the advice. We’ll try it on a small piece.

Tinkerman, I suspected something like this already, that’s why I asked. Thanks a bunch!

Hi!
just wanted to update you guys on our progress…
(and BTW thanks for all the advice!)

we eventually made a silicone layer, and on top of it put a 120 gram sketch paper , and then the Rosco Grey.

here you can see the final result…
(on some occasions it seems to miss the blobs, - but its only due to the face that the Rosco is just lying on the display… ( not fastened in any way) and i didn’t want to apply to much power on it so it might fall…

Enjoy!

http://www.touchproject.net

Roey and Itamar