How much filament is on a spool ?

[EagleSeven]

Anyone know about how many feet or yards of filament is on an average 1.kg spool of 1.75 mm filament ?

I'm trying to develop a formula for determining how much filament is needed for different sized objects,
by estimating their surface area, then determining how much is used for those objects by measuring spool weight difference,
before and after printing them.
Then convert weight difference into a length measurement.


Hobbies are Fun !

[Davo]

I'm trying to develop a formula for determining how much filament is needed for different sized objects,

Many slicers tell you how much material it will take to do the print.

With Slic3r, it's the first comment line at the end of the print:

...
G1 X106.227 Y121.710 E2.81031 ; perimeter
G1 X106.077 Y121.332 E2.82745 ; perimeter
G1 X105.966 Y120.941 E2.84459 ; perimeter
G1 X105.892 Y120.539 E2.86182 ; perimeter
G1 X105.865 Y120.158 E2.87790 ; perimeter
G1 X106.094 Y119.942 F1800.000 ; move inwards before travel
G92 E0 ; reset extrusion distance
M107 ; disable fan
M107 T10 ; turn off fans and lasers
M104 S0 ; turn off temperature
M140 S0 ;turn off the hot bed.
G91 ;
G1 Z5.0 ; Drop bed 5mm for extra clearance
G90 ; absolute
G28 X0 Y0 ; home X axis
G92 X0 Y0 ; confirm we are at zero
M84 ; disable motors
M30 ; End ofprogram
; filament used = 4819.4mm (11.6cm3)


; avoid_crossing_perimeters = 1
; bed_shape = 0x0,275x0,275x225,0x225
; bed_temperature = 80
...

[EagleSeven]

Yes, Since the slicer software we use, Makerbot-2.4, does not have that great feature,
is the reason I'm trying to develop my own.

Even if you know how much was used during a print, using software, we Still need to know how much is on a new spool ?
And an easy way to measure how much is Left on a used spool, by using a weight measurement ?
We have many used spools with Some filament left on them
but no way to determine if it is enough left to complete an object.

I searched the internet and have found No lengths of a full 1.kg spool !

[Davo]

Ah. Try http://www.toybuilderlabs.com/blogs/...ume-and-length

Top result from http://www.google.com/search?client=...in+a+1kg+spool

[curious aardvark]

1.75mm abs and pla are around 330 metres. And simplify 3d gives you: volume, length and weight :-)
You have to work out the length of unextruded filament yourself, as it gives you the length of extruded (ie: 0.4 mm versus filaments 1.75). So it's just easier to go by weight.

[EagleSeven]

Okay, Great !
Thanks for the Info !

1kg of PLA =330M
1kg of ABS =400M

I did not realize PLA was that much Heavier than ABS !
Also did not realize spool of 3.mm filament is 1/3 the length of 1.75mm

We will start checking weight of new spools, as we get them,
and mark any that are Not really 1.kg, with their correct weight.
So we can determine how much is left, as we use them, by weight change.

[EagleSeven]

! ! ! First new filament spool weight is 1,216 grams ! ???
(PLA filament)

So, either they added some extra filament or the spool weighs more than normal ?
The spool does look solidly made but don't think there is 200 g there. LOL

New Spools are from Hatchbox, which is very good quality, so maybe they did add some extra filament.

Note: I'm sure the Balance-Scale is correct , since we have calibration weights
BalanceScale.jpg

[EagleSeven]

Now I'm curious how much the Empty spools weigh ??
There are many 1.kg spool designs, with different size center hole , different widths and diameters,
and completely different wall-pattern designs,
which is complicating this even More !

Spool weight difference can greatly effect the calculation of length if there is not much filament left on spool.

Looks like my 'Length formula' is going to include a Lot of Guesstimating . LOL

[Marm]

Well, 1 kg of ABS (or any material) filament at 1.75mm diameter shouldn't be that hard to figure out.

using www.WolframAlpha.com, we see that ABS is 1.07 g/cm3 (median, .9 - 1.53 g/m3 are ranges provided), or .00107 kg/cm3 (.0009 - .00153 kg/cm3)

1.75mm D is a circle with an area of .0241 cm2.

so (1kg)(cm3/.00107 kg)(1/.0241cm2)= 38,779.23 cm or 387.8m. But that's if there is nothing else other than the filament. With the range provided, it will go as high as 461m or as low as 271m.

So you could cut off a 1 meter length of filament (with a volume of 2.41 cm3), find out the density of it by weighing it, and easily calculate the mass of the spool or the length of the remaining filament just from weighing that one meter length, once you know the other value.

You could also use this method to check how close to tolerance the diameter of the filament is, if the manufacturer provides you with the density of their material. If you're really going to get precise, you could use the displacement method to find this out if they don't

[EagleSeven]

Well, 1 kg of ABS (or any material) filament at 1.75mm diameter shouldn't be that hard to figure out.

using www.WolframAlpha.com, we see that ABS is 1.07 g/cm3 (median, .9 - 1.53 g/m3 are ranges provided), or .00107 kg/cm3 (.0009 - .00153 kg/cm3)

1.75mm D is a circle with an area of .0241 cm2.

Thanks for the info,

we are no longer using ABS, too much warping,
but I will try to find the numbers for PLA and HIPS.

But until I can get weight numbers for empty spools , that the filament is on, it still will be only Estimating and not accurate.
We certainly don't want to remove filament from spools to do measurements.