Difference between the 1.75 and the 3mm hot ends???

I'm completely new to RepRap and actually devices like this but am very excited to do such a project. What's the advantages/disadvantages of the sizes for the hot ends???

1.75mm requires less torque to extrude (less pressure).

Thats really the only major difference in terms of performance. However depending on your location it might be easier to get 1.75mm or 3mm filament.

Ps. Its the nozzle diameter which affects resolution.

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Thanks for the response.

I guess I'll try the 1.75mm then if that's better resolution. Ultimately, it's gonna be some great experience for me regardless.

Nathaniel,

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I guess I'll try the 1.75mm then if that's better resolution.

That's a common misconception. What Joe was trying to tell you in his Ps. is that the hole in the tip where the melted plastic comes out is what dictates the printing resolution not the size of the filament going in.
Also, I don't think anybody has mentioned yet that 1.75mm filament has to be fed 3 times faster into the extruder than 3mm to get the same flow rate at the tip. Larger nozzles printing at higher speeds could have a problem with that.
Just so you know: The original application for 1.75 filament was this http://blog.reprap.org/2011/03/reprap-universal-mini-extruder.html . So if you plan on using some sort of a mini extruder then 1.75 is a necessity, However if you plan on running it through a standard type nema 17 extruder like wades it's more a waste of horsepower than anything else.

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Blog

Bruce Wrote:
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> Nathaniel,
>
>
>
> That's a common misconception. What Joe was trying
> to tell you in his Ps. is that the hole in the tip
> where the melted plastic comes out is what
> dictates the printing resolution not the size of
> the filament going in.
> Also, I don't think anybody has mentioned yet that
> 1.75mm filament has to be fed 3 times faster into
> the extruder than 3mm to get the same flow rate at
> the tip. Larger nozzles printing at higher speeds
> could have a problem with that.
> Just so you know: The original application for
> 1.75 filament was this
> [blog.reprap.org]
> ni-extruder.html . So if you plan on using some
> sort of a mini extruder then 1.75 is a necessity,
> However if you plan on running it through a
> standard type nema 17 extruder like wades it's
> more a waste of horsepower than anything else.

1.75 requires less torque, so you can turn the current down on the stepper.

1.75 requires more steps for the same flow, but in reverse this gives better flow control especially with a small nozzle.

This is all Chinese to me right now but I know eventually I'll get it.

Appreciate the help!!!

Here in NZ 3mm fillament is cheaper than 1.75mm, so much so that it's a no brainer to use 3mm

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Experimenting in 3D in New Zealand

I bought a prussia with no extruder and electronics off ebay.
I also bought the parts for a wade extruder and lulzbot hot end.
I also order a set or RAMPS electronics. All the bits should be here by early next week.

I have a few Kg of 1.75 makerbot filamant.
Should I buy some 3mm or should I build the extruder for 1.75mm?

If I should build it for 1.75 what do I need to change?

I'm more itnerested in fine detail than speed, so I think the 1.75 gives me more lattitude for small build heights without
shreddign filamant, is this correct?