[ Closed ] Filament Extruder - Convert pellets to filament (Page 28 of 58)

i found a 20mm 3/4" stainless barrel nipple for 2.75gbp so about $3.50 ?? just not sure how long they are..goto give them a ring and find out

to be honest there isnt alot of detail on the web site?...its made of 316 grade stainless

they do 3/8" 10mm...1/2" 15mm and 3/4" 20mm but no info on length, wall thickness/shedule type
i`ll send them an email now and see how quick i get a reply

until i know what the i/d is i wont know what auger to use?

will post answers on here when i get a reply

what dia pipe do you use on beta 2?

listed as 150lb pipe fittings if it helps at all??

well the reply was.....

" The barrel nipples,we stock are sch40s 316 stainless steel.

We do make them to any lenght you require, in sch80s, sch160 or xxs.

Please can you advise what sizes you are interested in and we shall give you uor stock lenghts. "

sounds promising

I've been reading through that book for awhile, and Google books hasn't stopped me yet which is good.

Something it said about cooling gave me a thought-  the coiling that the filament always does coming out of the extruder may be caused by the fan.  The fan is quickly cooling the underside of the filament, causing the bottom to shrink more quickly than the top, bending it downward.  If there were two fans blowing toward each other, I wonder if it would extrude straighter and be easier to manage.

Yeah, I just read this in another book I skimmed through today. The pros use a fan duct that goes all the way around the filament and blows a ring. I'm not sure standard axial fans build enough static pressure to blow much through one of those. I'm willing to try!

I think the filament curves more because it comes out of the die at an curve, so as its cooling, it's setting in the form of a curve. I say this because the coils on the ground have about the same radius as that 90 degree curve coming out of the filastruder.

You guys are doing great work on here! Read the whole thing. Going to invest in one of these! Thanks for adding me to the list Tim. One question for you all. I am looking to extrude at 3 mm and was wondering how you all knew that a #52 bit would extrude at 1.75 mm. That is all I can find across the internet. I have no problems starting small and working up.... but that would be incredibly time consuming. Any help is appreciated!

Thanks for the info

hi,

Have almost got the extruder made, am now turning my attention to the motor.

From a previous post you said you needed 1-3RPM at 40 in-lbs (4.5Nm), so far I can't track a DC motor down in the UK for less then £80.

I was thinking of using stepper motors as they can be high torque and low rpm (and a constant rpm) but still no luck. Even stepper gearbox are expensive.

Which leads me to my last idea, use a 3.5Nm stepper i already have and 3d print a 2:1 set of gears and make a box out of 6mm steel. Which should (if the gears hold) work.

if anyone has any idea it would really help.

Tom

It's asking a lot from plastic gears. Make sure the diameters are as large as possible to reduce tooth load, the gears as wide as possible to reduce tooth load, and that you print in PLA, as it's harder than ABS.

Since you're using a stepper, you might be able to get away with just spinning it slower and not using a gearbox. This will obviously reduce output.

Did you buy the hotend or whole extruder?

I just had the hotend. I think my issues were because I didn't fully tighten the brass barrel into the PEEK. There's nothing inherently bad about their design.

I have heard bad things about their extruder, though.

I've heard it jams and strips filament easily.  There is a bolt and plunger for tension rather than a spring.  The plunger can't adjust for variations in filament diameter the way a spring does, so you have to get the tension just right.  Haven't heard anything bad about the hot end though.

Forum posts on it:

http://forums.reprap.org/read.php?1,172178,172178

Review:

http://www.buildlog.net/wiki/doku.php?i … provements