How long is the filament on a spool?

When loading a gcode file into Pronterface, it gives an estimated length of filament used. However, filament is sold by weight. Does anyone know how much filament is on, for example, a 5lb spool of 1.75mm PLA?

It would be nice to know, for example, if I have used (X) amount of filament from a spool, then I have (Total - X) left on the spool, and so I could immediately know if I had enough remaining to complete an object.

Obviously, I could measure off a few meters of filament and weigh it, but I thought that someone might have already figured it out.

Also, how accurate is the length given in Pronterface? I assume it should be exact, but is it?

Thanks.

The faberdashery site says for 1.75mm PLA "100 meters is about 300g or 241cc".

Therefore 100 meters = 0.661387lb.

Therefore 755 meters = 5lb.

Andy

Skeinforge can output a report saying exactly how many grams are extruded in the print. You can even punch in your cost of material and it will calculate how much it will cost in plastic.

Ok, thanks for the info. I use Slic3r, so the Skienforge option doesn't help, But if I use 750 meters as a guide, I shouldn't ever run out.

Does anyone know how accurate the Pronterface length estimate is?

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Does anyone know how accurate the Pronterface length estimate is?

I think it is very close. If your e-steps/mm is off, this will of course introduce error. But I never bothered to measure its accuracy down to the last centimeter.

Slic3r also writes the length and volume of filament needed as a comment on the last line of the G-Code file. Pronterface independently reports a very similar value (Slic3r's 3317.5 vs. Pronterface's 3316.48 mm on a thing I'm printing right now).

Pronterface's initial time estimate is pretty bogus, though. I wonder how it's calculated...