Should I use a raft when I generate the gcode?
Yeah, probably. We've had a number of problems with things being too thin for the 'resolution' of the printer. This has led to scoring of the table, and ripping up of the plastic cover. Unless you already know your item is not gonna do that, use a raft. Just pull it off after building before it completely solidifies.

I can't find the icon, where's the executable?

You will have to have write access to the usb device. Check with the hackerspace mentor if you have trouble.

How long does it take?
The most often asked question has two answers: "a long time" and "not so long". For most objects, rather a lot of time is spent bringing the temperatures of the nozzles and table up to the appropriate values. The thing spends a lot of time (for small objects, over half of the time) just sitting there warming up. Once it starts actually laying down filament, its much more fun to watch, since something's actually happening.

Print Problems
If you find that the heads are moving so fast that they are shaking the item off its position on the plate (this seems very common the smaller the item is), slow down the "Travel Rate" on the heads (in the "generate GCode" menu item.)

The default is 30. We've had good results setting it to anything from 20 to 40. Faster speeds mean faster finishing (presuming it finishes). We've found that making the feed rate the same value as the travel rate a good rule of thumb.

Also, change the "Feed Rate" from 30 to 20 if you change the "Travel Rate" to the lower rate. This also cuts down on shaking, but still allows the device to 'grow' properly.

However - setting the speed/feedrate too low can give the item time to warp during building. So you have to be careful. The warp problem is most common on wide but not too tall objects. Note also that the feedrate and travel rate are remembered from the last user's settings, so you pay attention. (At least, after the first time it messes up :-)

Head Cleaning(of the nozzles in the makerbot, smart-XXX)

Here is the procedure for cleaning the nozzles -- if the heads wig-wag back and forth to build your cool-thing, but nothing comes out, that may well be because the nozzles are clogged.

Wipe them both with Nail Polish remover and paper. WARNING: Nail polish remover is FLAMMABLE! Do not perform this wiping while the nozzles are hot.

Open the ReplicatorG program and select the manual controls for the makerbot.

Set the Left and Right Extruder temperature to 220C.

Once they reach that heat, press the forward button above the temperature box in the program and watch the plastic come out in a little thready thing. (Do this for both nozzles)

If nothing came out, CAREFULLY remove the black tubing that is hiding the filament above the nozzle assembly (it should not have to be forced. The little plastic ring it feeds into does NOT come out.) Press the forward button in the control box of the replicatorg program and at the same time feed in the filament with your hand for the extruder you are working on (Repeat for second nozzle)

If things still aren't working, it is possible that the spool of filament has stopped feeding filament properly (the time this happened, the filament been crossed over itself by improper unspooling and rewinding by an exhuberant civilian). In that case, you'll have to unload and reload the filament. Obtain the help of a Hackerspace employee. You'll (or said employee) will have to unload the filament (using the "M" button and the up-down-left-right buttons on the makerbot itself to get to the 'unload' filament section.)

Once the filament is unloaded (this procedure is also obviously useful when changing a filament to a different color), pull it back through the tube to the spool. Get things a-right (note which way the filament unspools from the roll before changing things), then feed the filament through the little tubes, and back to the above-mentioned nozzle assembly.

Use the "M" and the up-down-left-right again to get to "load filament", let the filament load, and repeat the 220C-and-forward-button procedure to make sure plastic is melting and flowing well through the nozzles.

Once the plastic thread is coming out, replace the black tubing.

Once everything is coming out properly, just close up the manual control window in 'replicatorg' and you're done.

The various filaments do not operate super correctly at the default temperatures. We have found that white (beige) filament works better at 210C, red at 215C, and black at 220C, and white (actually white) at 225C. You may have to tweak temperatures to get your object to build. Things seem to work better if the table temperature is 120C (the default is 110C.)

The 'use raft' checkbox should be carefully considered, especially if the object being built is not tall, but is large (e.g. "embossed" logos.) It does use more filament, but our experience is that its use in the not-tall-object situation winds up saving filament from failed attempts. Tall but thin objects (that may not stand on their own during build) should use "full support." Tall but sturdy items probably don't need a raft.

For large objects, we've (and others) found that the temperature of the air can cause the bottom of object to curl up during building (with the resultant possibility of the object moving away from where it should be during build.)

There are two solutions -- one is to 'pause' the build in the replicatorg program (but not for long!) and tape the edges down, then continue. This is most easily (but most dangerously done -- and is therefore recommended under any circumstances) done with the 'raft' feature turned on, since the object's raft will be larger than the object, and easy to get to. DO NOT USE SCOTCHTAPE OR ANYTHING LIKE IT TO DO THAT! Use the 'klapton' tape. Use a small amount of one of the thin rolls. REMEMBER THAT EVEN THE PLATE IS HOT; HOTTER THAN BOILING WATER. Thus, although this procedure is described (for educational purposes) is positively discouraged.

Another solution is to simply get two thin devices (for instance, the x-acto blade and the file) and just hold the edges down carefully while the object is built. This can be a little hard on the hands, after a while, but it does in fact work. Again, using the 'raft' feature is handy.

The other solution is to put plastic covers on the sides of the makerbot itself to cool stop air moving through the build area and cooling off the object too quickly during the build procedure. The crack Hackerspace staff applied this fix, which seems to have some effect. (Actually, that's three solutions.) Anthony Velazquez figured much of this out

I'm trying to 'emboss' on both sides, but the bottom side isn't great It appears that gravity has an effect in this sort thing. 'rafting' can make it better, or sometimes not -- it depends on the geometry you're using. Sorry to not be very helpful, but its a complex issue, it turns out.

It doesn't look very good -- the edges are all wonky, for instance. It is increasingly apparent that the 3d printer has characteristics analogous to pixilation in 2d images. The closer one gets to the resolution of the extruded filament, the worse things look. Bigger is better. Also, if you get things too thin, they get optimized away entirely when converting from geometric descriptions to squeeze-this-there descriptions.

The raft is stuck on solid! It is also apparent that for thin items, a raft pays off. But you have to remove the raft before the item solidifies entirely after fabrication. Otherwise you can wind up with a waffle look to the bottom of your thing. This problem does not occur with the "full support" vertical supports, because your object is not resting on them, but will with the raft.