extruder

hello

I'm building my first 3d printer.

I'm using a arduino mega2560 running marlin firmware

The question I had I want to build an extruder with this: [www.ebay.com]
it has 0.1mm nozzle diameter and I want know that which is the best gear ratio to get the best quality printed parts?
And which is the best value what I have to write in to the marlin (configuration. h -> step per mm unit, extruder )? When this value is near to 0 or better when this value near to another value?
My English knowledge not the best so please pen clearly.

Edited 1 time(s). Last edit at 01/27/2015 12:18PM by simonekfia.

0.1mm nozzle is pretty thin ! If you're not skilled enough, thin nozzles can drive you mad. May I suggest to try a .4mm nozzle first ? Any Wade extruder for J-Head or E3D V5 will fit. Usualy it's around 10-40 ratio for the gears, but it does not matter if it's a bit different. Just calculate the good values during the setting.

The formula is : wade : e_steps_per_mm = (motor_steps_per_rev * driver_microstep) * (big_gear_teeth / small_gear_teeth) / (hob_effective_diameter * pi)
Attention, because hob tooth may come inside the filament, an experienced calibration is needed after.

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

Okay I read about that but when I calculate e_steps_per_mm (I attech a picture about the result) how can I decide which result value is the best for me? I know that I have to this number in marlin.ino. If I use the smallest value in marlin, the printing quality can be better ? or it doesnt matter?

You can't "decide" about values. Steps per millimeter are calculated values, to match your hardware. If that values are not set properly you will have print quality issues, whatever the value is set too low or too high. That value must be calculated the most acurately possible. It's a machine, not coocking. You can't adjust values like salt and pepper in a soup. You just want the right values for the components used in your machine. To get the right value, use the calculation formula in my previous message.

Believe me or not, but print quality first depends of the right calibration of your machine. Neither too much nor too little. The maximum reachable print quality depends of the overall build quality of your machine. But this commes later. The first goal is to make the machine works fine. It's a difficult job. You need to accomplished this quest with a standard 0.4 nozzle before to go further. When you'll get it right and aquired some skills in FDM 3D printing, then try smaller nozzles if you think you realy need it. To me a 0.3mm is pretty enough (and long enough !). Keep in mind that a cheap chinese printer will have some wobble that exceeds any nozzle diameter size ! To get high quality prints, you need high quality components for your printer (and a high quality budget through...). All matters in a 3D printer, like in any machine. If you have a cheap car, don't expect to win competitions with it, even with a competition exhaust, or custom parameters in the injection calculator.

IMHO, you're talking about 0.1mm nozzle with no experience of what difference nozzle size makes. Maybe you want to own the best possible machine. Good. But does it realy matches your needs ? 0.1mm nozzle does not mean you will reach 0.1mm precision on your printer. Not at all. If you realy need ultra fine precision. Don't go on a FDM machine, and go for a SLA printer. Decreasing drasticaly nozzle size will brings a bit of improvement whereas exponentialy increase printing time. If you don't need ultra fine details like 0.1mm walls on your part, you don't need a 0.1mm nozzle. The thinner it is, the fragile it is. If you want fine detailed small scale figurines, go for a SLA printer. Anyway, if you want a high definition printer, save for a high definition budget. There's no halfway.

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

This.

If you have a wade extruder, count the teeth on the gears, and use the appropriate ratio in order to set your steps per mm.

Regardless of the calculated value, because it won't come out exactly right (Though if you use correct values that match your hardware, it should be close) you will want to do a final adjustment. Triffid Hunter's calibration guide (http://reprap.org/wiki/Triffid_Hunter%27s_Calibration_Guide) is a good read, and you should.