Tag Archives: scientific method

Once More, With Rigor

This is a follow-up to yesterday’s post on printing with PLA, where I claimed that the orientation of the painter’s tape on the build platform is important to the stick-to-it-ive-ness of a PLA print.

But is it? Really?

A comment from CymonsGames (who’s doing some great stuff on Thingiverse, BTW) got me thinking. Is this 3d-printing feng shui, or is this a real effect? Does the grain of the painter’s tape matter? It worked once yesterday.

But anecdotes ain’t data, people. Imma test this.

I’ll try and remove as many variables as possible from the experiment, but since my basement clean room is currently occupied by an eldritch horror I’m stitching together from abattoir scraps, I’ve got my Replicator in the living room and ambient temperature control isn’t really possible. It’ll be somewhere between 64° and 69°F.

I made a special model for this print test: it’s just a 30x30x2mm solid with a raised zheng on it.

And some skeuomorphic rivets. Because, rivets.

Most importantly, this model is thin, so I can run this print a bunch of times quickly.

ReplicatorG Settings:
10% infill
.22 layer height
print 240° on first layer, 210° afterwards
HBP: 35°C

I used fresh tape before every print, all from the same roll. The first three prints were with front-to-back tape, the next three were with side-to-side tape. All tape was the same stuff, 3M Scotch 2090-1A ScotchBlue Painter’s Tape.

Minor tip: Make sure you have tape everywhere that you plan to lay down PLA, especially the homing line from the corner of the build platform to the start of the print. If you miss that little detail, your print head may end up dragging a blob of plastic all over your first surface and mess with the print.

Here are the results:

In summary: these tests don’t show much difference in stickiness with different orientations of painter’s tape.

I even mixed up the orientations just to see if I could mess up the print. No good. Every print looked more or less the same except for a little curling on front-to-back #1.

The information contained in that last post is no longer operative. Put your tape on side-to-side, front-to-back, whatever gets you through the day.

Scientific method. For great justice.