tips on diy filament extruder

Guys i know that this is not the proper place to ask but i am desperate so i could use some help. Getting to the point. Last september i ve started to build my do it myself filament extruder . The first machine was a bad one so two months ago i started a new one using a lathe this time.

I am able to extrude some filament but at this moment i am stack as i cant produce the right diameter. Explaining what i am saying i am trying with and without fans for cooling. In any case i am getting difference in diameters as the filament drops on the floor. I have the extruder 1.3 meters above the floor and i am getting from 1.70 ( when it is hanged by its weight ) and 1.8 when it hits the floor .

So i would like to know if any users around here use their own filament extruders and how do you handle the hot filament that is coming out of the nozzle. Any tips would be more than great ..!

be well guys.

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Delta Printer
Duet 0.8.5 firmware 1.19

what you want is a puller, you measure the diameter as it comes out, then stretch it to make the filament thinner. The construction manual for the lyman extruder may give some good ideas: [www.thingiverse.com]

thanks man for the tip. so there is no alternative to that i suppose ?

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Delta Printer
Duet 0.8.5 firmware 1.19

Just move your extruder to a higher position or make a smaller nozzle would help in getting the correct diameter. Lots of info to be found on the filastruder forum about this

Edited 1 time(s). Last edit at 04/03/2016 05:55AM by Frans@France.

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Frans@France
Just move your extruder to a higher position or make a smaller nozzle would help in getting the correct diameter. Lots of info to be found on the filastruder forum about this

i had it closer to the floor and then i raise it up a bit. it didn't help . also i had 1.35 hole and then i went to 1.7. that didn't help either. the filastruder forum doesn't have diy builts ( or at least i didn't found any ) buy only the the filastruder extruders.

anyway i ll disassembly that today to see what is going on and then i ll get back to you.

i also printed and assembly a puller but it didn't help either as it is to fast for the extruder, even in it's lower speed with pulleys that reduce 10:1 the turning rate.

i am so tired of this built. The funny thing is that my first build which was awfull produced better than my second one. My second oone has been build to a lathe but it didn't helped.

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Delta Printer
Duet 0.8.5 firmware 1.19

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Gaou
i had it closer to the floor and then i raise it up a bit. it didn't help . also i had 1.35 hole and then i went to 1.7. that didn't help either. the filastruder forum doesn't have diy builts ( or at least i didn't found any ) buy only the the filastruder extruders.

Nothing about the filastruder that can not be used for your own extruder when using the same gravity based width control technic. If you're extruding ABS then nozzle size, temperature and height is important to get to the final width including correct placement of the fan and controlling the stability of the temperature. Also your type of ABS and it's specifications like flow rate will influence the optimal settings.

Using a puller will only work when using a much larger nozzle so that there is something to pull into a smaller width. The lyman uses a 4.5mm nozzle. A puller will allow for higher production rates then gravity based extruders but are harder to control.

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Frans@France
The lyman uses a 4.5mm nozzle.

i didn't knew that. what diameter the filastruder use ? and if you don't mind asking what do you use?

when i started i started with 1.2 going up to 1.5 that i drilled today. in the past i even used 1.35 1.25 1.45. but i saw that this is not so important as it changes as the temp change .

anyway i ll see today the 1.5 and some changes i ve done and i ll post again.

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Delta Printer
Duet 0.8.5 firmware 1.19

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Gaou

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Frans@France
The lyman uses a 4.5mm nozzle.

i didn't knew that. what diameter the filastruder use ? and if you don't mind asking what do you use?

when i started i started with 1.2 going up to 1.5 that i drilled today. in the past i even used 1.35 1.25 1.45. but i saw that this is not so important as it changes as the temp change . .

Filastruder is using 1.58mm (source:[www.soliforum.com])

I started with a lyman v5 and rebuild it completely.

Edited 1 time(s). Last edit at 04/05/2016 02:10PM by Frans@France.

With any filament extruder you will need to discard the first few feet of filament. The diameter won't be consistent until the conditions of extrusion reach a steady state. Once it has started to coil on the floor, is the diameter consistent? It works best if there is enough open space below the extruder that it can coil in a circle with the nozzle at the center. If there are table legs or other things under the table for the filament to bump into, it will have a hard time maintaining diameter.

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IanJohnson
With any filament extruder you will need to discard the first few feet of filament. The diameter won't be consistent until the conditions of extrusion reach a steady state.

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IanJohnson
Once it has started to coil on the floor, is the diameter consistent?

No it isn't . i am getting at this moment with current setup from 1.68mm-1.76mm

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IanJohnson
It works best if there is enough open space below the extruder that it can coil in a circle with the nozzle at the center. If there are table legs or other things under the table for the filament to bump into, it will have a hard time maintaining diameter.

That's my problem and that's why a puller would be a solution . The extruder is sitting in a very tide space so the filament in every 80cm finds different resistance as it hits walls, chair legs etc so i am getting this difference in diameter.

I ll try first of all to make a new puller with lower gear ratio ( the first i ve made was something aabout 40:1 ) to see if it can help as the pulling force would be similar during the extrusion...!

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Delta Printer
Duet 0.8.5 firmware 1.19

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Gaou
No it isn't . i am getting at this moment with current setup from 1.68mm-1.76mm

But +/-0.04mm is well within professional filament specs......Do you want better results?

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Frans@France

But +/-0.04mm is well within professional filament specs......Do you want better results?

what ? is it true ? i want the filament to get to 0.005-0.01 difference . very weird . what are you getting Frans on urs Frans ?

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Delta Printer
Duet 0.8.5 firmware 1.19

the filament i buy has a tolerance of +- 0.03mm, most are +-0.05mm tolerance

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Gaou
what ? is it true ? i want the filament to get to 0.005-0.01 difference .

Then you would be close to the stratasys usd200,- filament specs and no the standard usd 20,- rolls

looking forward to your objectives for the roundness

Edited 1 time(s). Last edit at 04/08/2016 01:03PM by Frans@France.

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Gaou
what are you getting Frans on urs Frans ?

I'm stuck at +/- 0.1mm (high/low not std. dev.) at the moment but that's for an extruder speed around 9,000mm/min for 1.75mm. Searching for improvements for some time now before increasing extruder speed any further.

i haven't had any filaments except one chinese abs. at that time i meausre it and it was somethign about +/- 0.04. my first extruder was at +/- 0.06 . Thats why i left it and builded a second one . I wanted to be more accurate...!

But if that's the case guys then i ll stop looking around and try to archive some small improvements as probably i would loose my time trying to do the impossible.

Be well guys thanks for ur tips .

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Delta Printer
Duet 0.8.5 firmware 1.19