Wednesday, 25 July 2012

I'm currently trying a 2mm thick piece of acrylic sheet as a build platform. I like the idea that it is lighter than the glass, so in theory it should have less inertia when the platform starts and stops. And ABS seems to stick quite well, but on one occasion I tried wiping the sheet with acetone. Unfortunately this enabled the ABS to stick pretty much permanently. Hey no warp though!
Time will tell how the ABS stands up

Monday, 9 July 2012

A Sticky Situation

Well lately I have been experimenting with ways of anchoring parts to a glass printing platform. Kapton tape, for me, had limited success as it would lift at the models corners allowing for warping. It's also very easy to damage when removing models, requiring constant re application. Blue painter's tape gave similar results.

So I tried a mixture of acetone with some pieces of ABS mixed in an empty nail polish bottle. Spreading this out over the glass plate worked quite well, except, like the Kapton tape, with larger models it pulled away from the glass at the corners.

Next on the list of thing to try. Clear nail polish !  I originally bought these cheap from a store to use the bottles. The clear seemed like it would be the easiest to clean. But I decided to apply the polish direct to the glass before tipping it out. Damn this stuff stinks ! My room soon started to smell like a beauty shop.

I selected a particularly troublesome part that is large and flat, hit print and sat back to watch. The first few layers came out and stuck really flat to the glass. All looked good, so I left it to do its thing. When I came back I was greeted with a nice flat model that had virtually no lift on the corners. SUCCESS I thought ! So I removed the glass plate and proceeded to remove the model. Well this is where the problems started. I managed to get under the edges, but as I worked towards the middle the part became harder and harder to remove. Eventually the model popped off, but when I looked at the plate there seemed to be something missing !! Sure enough there was a thin layer of the glass plate still stuck to the middle of the part ! OK, so it looks like I have found the ultimate adhesive for printing direct to glass. Next I am going to try adding some acetone to the polish to thin it out a little, hopefully making it easier to remove prints, but still hold down those pesky corners.

Here is the piece of glass, showing the sliver taken out. Unfortunately it also broke getting a subsequent model off.