[ Closed ] Filament Extruder - Convert pellets to filament (Page 48 of 58)

Looks like the hopper is the same, the funnel is different. Do you mind posting a STL/CAD file?

About masterbatch: It's pretty easy. If the instructions call for say, 50:1 ratio, then take 1tsp of masterbatch, mix with 1 cup pellets:

then stir:

Then, spool it up:

and print:

Here's a finished hopper, Filastruder filament.

Printed at 90mm/sec perimeters, 113mm/sec infill. Pretty fast for a Solidoodle.

Hard to really capture in photos, but the coloring is definitely consistent. Just like the OEM black parts on the Solidoodle.

This is how we bag plastic BTW

Ha, I was confused until I looked at the image again. My dad found that in a house he bought. I do plan on using it eventually. I feel it is important to let your employees know they are safe. They also don't want to be the one to reset the date.

Thanks for the demo Tim.

This question/suggestion is probably more for OSP.  I know you guys are looking into getting various colours of ABS masterbatch.  The link Tim posted a while back called for a ratio of 1%.  The suggestion above is 2%, so presuming these numbers are consistent in general for masterbatch, then the 2oz bags you sell in your store will do about 2.5kg of filament.

How about offering a rainbow selection of masterbatch (either in store, or on KS)?

Thank you for the suggestion. Once the KS end, we will be doing an overhaul of our inventory and will be adding much more. So you can expect to see color packs and other arrangements.

Typical masterbatch ratios are between 25:1 and 100:1.

Rob (OSPrinting) is meeting with a masterbatch sales guy late this week. I'm sure they'll offer colors if they can!

Sure, but that takes, like, 5 minutes!  When I do this I usually pull some plastic out of the barrel with tweezers.  As it cools it becomes like taffy and snaps back behind where the threads are so I don't need to worry about it interfering with screwing on the nozzle.  I especially do this when changing bolts in the plug that I tapped.

Here's some pics of my beta.  What kind of variation are folks seeing in filament diameter?  This table top was only about 30" off of the ground. I think there was a lot of interaction with the pile of filament on the floor, preventing uniform pull at the extruder tip.  Here's some quick data I took at 200C marking off 1 minute of filament.  Suprisingly, motor current did not seem to increase with motor voltage and ranged between 260mA and 300mA.  No real correlation between Motor Voltage and filament thickness.

Motor        Filament               Thickness  (mm)
Voltage     Length (Inch)         Min         Max
12            11.9                     1.67       1.73
13            12.5                     1.70       1.75
14            13.8                     1.60       1.75
15            14.4                     1.63       1.77

Pics below shows the funnel Tim printed up for me with filastruded filament.  Not too shabby.  Pipe slot was cut exactly to spec, but ended up a little too close to the flange when the hopper was added.    Using T nuts and washers allowed the hopper to be placed closer to the flange.  Next time I would preinstall the pipe in the flange and measure out where to place the slot.

Used an 11/32" x 3/8 drive socket with a 3/8" brass strip to engage the D shaft section of the gearbox.

Had 0.030" of run out on my pipe flanges.  Didn't want to dink around with shims or offseting the wood supports so I cheated and trued the surfaces on the lathe.  Screwed the flanges onto the pipe and chucked the pipe.  Worked great.

Another way that would have worked would have been to drill oversize holes for the motor mount and attach with fender washers so it can be moved around.  Center the gearbox shaft by sighting down the inside of the pipe.

The pellets appeared to jam where the auger entered the pipe going to the heater assembly inside the tee.  I had a discussion with a friend about the problem and he suggested a solution so I am going try it out tonight.  I will let you know if if it works or not.

Bob Teeter

Every report I've seen has been just about +/-0.03mm @ tav.
The slot is a bit close to the flange, depending on how tight you get the pipe, and whether you notch the hopper for the nuts. The t-nuts are a great idea!

Did you not have a 9mm socket and washer (key) in your kit? I might have run out when shipping yours, it was one of the last ones.

I think you're the first to lathe the flanges! I intentionally left the design unconstrained, so perfectly flat flanges aren't a requirement. Cool that you have the materials to do it, though!

Hey Dennis - Agreed.  My bad.  I was thinking propeller torque in air proportional to RPM^2.  This ain't air.  This is ultimate goo.  Reynolds Number <<1.  Torque is proportional to RPM.  Motor Rs=13 Ohms (=> stall current @12v ~900mA).  Io~90mA.   Nominal observed operating current ~260mA @12V.  Ideal motor voltage 12-0.260*13= 8.62V.   Motor output efficiency is only Pout/Pin = (8.62*0.17)/(12*0.26) =46%.   Set up and solved the first order motor equations.  Based on the 12V data, assuming internal pressure is proportinal to RPM and extrusion rate is proportional to internal pressure, the predicted filament rate at 15V was 14.7 in/min vs 14.4; predicted motor current 307mA.  Will re-measure.  I was just eyeballing current expecting an RPM^2 effect with good motor efficiency.  Didn't want this to get off topic and turn into a math-fest, but not bad for a kitchen timer and some sharpies.