Fan. Perspex case. Glass Bed. Acetone part finishing. (Page 1 of 2)

I figured that I should contribute to the community as it's been a great source of information for me. Rather than split all this across multiple posts I figured I'd just cover a number of topics at once - hence the title.

#1: Fan addition.

I took the Lawsy/Ian Johnson design (http://www.thingiverse.com/thing:30828) and modded it slightly to allow for the larger neodymium magnets I got from amazon (http://www.amazon.com/gp/product/B001KV … 00_s00_i00). I hooked up a 40mm fan also from amazon (http://www.amazon.com/gp/product/B000RD … 00_s00_i01).
Fan Front: http://www.flickr.com/photos/jenninaj/8 … hotostream

I tied the cable off to the main loom of the print head
Fan side: http://www.flickr.com/photos/jenninaj/8 … hotostream

Power was via a Zalman varible speed controller left over from one of my many computer builds.
Controller: http://www.flickr.com/photos/jenninaj/8 … hotostream

I got power directly from where the wall adapter brick is wired to the arduino (I'm sure someone will comment on the sanity of this).
Power connection: http://www.flickr.com/photos/jenninaj/8 … hotostream

I've got the whole thing running well now and use it on thin areas, like the antennae on the brain slug (http://www.thingiverse.com/thing:33325). I try to persuade myself that it makes a difference but the jury is still out on that one.

#2: Perspex case.

I didn't buy a case for my SD2, as I thought I'd want access from multiple directions. With the hot summer I fired up the ceiling fan and noticed that my bed temperatures fluctuated. So, rather than build a complete case I got some perspex sheeting and ripped it into 12" x 12" squares. I attach the sheets to the printer with some of my handy neodymium magnets from project #1. The result is an enclosure that I can quickly get to any side of the printer but in general use is quieter and doesn't have the temperature fluctuations.
Perspex: http://www.flickr.com/photos/jenninaj/8 … hotostream

#3: Glass bed.

After tearing my kapton tape for the zillionth time (mostly by being impatient and spanner-handed) and being frustrated with the indentations from the screw holes in the heated bed showing in my prints, I decided to go with a glass bed. I got the 2.5mm glass from Home Depot and cut it to 5.75" x 5.75" with a glass cutter. I polished the edges to stop me losing a finger (or something more valuable) and clipped it to the bed. I'm really pleased with the results on the prints and it's way easier to get them to release. I cycle the temp from 100 C (printing temp) down to about 60 C and the prints either release on their own or take a little persuasion with a sharp knife (now I don't have to worry about slicing any tape). I would recommend this to any SD2 users out there.
Glass bed: http://www.flickr.com/photos/jenninaj/8 … hotostream

#4: Acetone part finishing.

I've played with brushing or pouring acetone over the parts and while this works well to bond the layers it can leave unsightly brush marks and/or a white cloud on the print. I wanted to try acetone vapour and small scale tests in a jam jar (sorry, wifey) were promising. I pondered how to scale up for larger prints but didn't want to go for any powered/heated system as I know how much 'fun' a vapour fire can be...not to mention hot fumes for eyes and lungs.

I finally settled on the following: a clean gallon paint can from Home Depot (just a couple of bucks), some paper towel, the ever-useful neodymium magnets, and some scrap metal.

I put the towel around the inside wall of the paint can and hold it there with the magnets (so easy to position and to replace the towel). The scrap metal was bent at each end to hold it up out of the liquid acetone. To prime the system you simply pour in some acetone, hold the lid on gently, and shake. The towel becomes wet with acetone which means the vapours are more evenly distributed around the entire can. Also, the towel draws more acetone up by capillary action and again this keeps the vapour pressure more even.
Paint Can: http://www.flickr.com/photos/jenninaj/8 … hotostream

Because the parts can be soft after the acetone treatment I added another piece of scrap metal as a tray I can put the part on and lift the part in/out with. I used scrap with holes in to help the vapour get up and around the part (the scraps are simply nailing plates that Home Depot sell for connecting timber sections together and are a few cents each).
Tray: http://www.flickr.com/photos/jenninaj/8 … hotostream

I typically leave the print in there for 30 mins if the garage is about 72F and longer/shorter time as the temp goes down/up.

Once I'm done with the bath I just tap the lid down and the acetone stays in there without any loss.

You can see some examples of smoothed parts below
Cthulhu before and after: http://www.flickr.com/photos/jenninaj/8 … hotostream
Cthulhu red and yellow: http://www.flickr.com/photos/jenninaj/8 … hotostream
Metropolis: http://www.flickr.com/photos/jenninaj/8 … hotostream
Duck: http://www.flickr.com/photos/jenninaj/8096960984/

Comments and thoughts welcome.