Sunhokey Prusa i3 Z lead screw question, sorry for noobness

So I have had my printer runnign for a couple months now and I am trying to figure out how to get rid of banding I am seeing in the Z axis. I have come across the RepRap calculators but I am not sure what my leadscrew pitch, pitch presets and gear ratio is in order to find a good layer height to set the printer to.

I currently run a .2mm layer height.

Thanks so much,
Chris

You tried using the 8mm presets? Don't get confused between lead screw and acme rods/screws(?). I don't know how to measure the pitch other than using calipers though

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sarf2k4
You tried using the 8mm presets? Don't get confused between lead screw and acme rods/screws(?). I don't know how to measure the pitch other than using calipers though

What are 8mm presets, presets in the calculator? ACME screws dont come with the printer correct? Not sure on the difference between what comes with the printer and the ACME stuff

That depends on some suppliers/sellers, some of them does ship them with acme rods, I guess this one much better than lead screws due to prone on being bent (a bit)

And yes, the presets from the calculator, unless you're using imperial lead screws, since you're using .2mmm layer but there's banding. What is your printer and link please? Maybe can find some info from there for your lead screws.

If you know what lead screws you're using already, kindly check this guide of calculating the steps/mm [reprap.org] then you go to prusacalculator to get optimum layer height

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sarf2k4
That depends on some suppliers/sellers, some of them does ship them with acme rods, I guess this one much better than lead screws due to prone on being bent (a bit)

And yes, the presets from the calculator, unless you're using imperial lead screws, since you're using .2mmm layer but there's banding. What is your printer and link please? Maybe can find some info from there for your lead screws.

If you know what lead screws you're using already, kindly check this guide of calculating the steps/mm [reprap.org] then you go to prusacalculator to get optimum layer height

This is the exact model I bought [www.3dprintersonlinestore.com]

That is definitely acme rods or known as trapezoidal rods too. I don't know how to tell the rod spec actually since it may come either metric or imperial. I'm sorry I don't know much about z axis rods supplied by sunhockey.

Maybe you could go a wee bit of a hard way, try printing in a layer height of .21-24mm and see the results

I'm sorry, I really do

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sarf2k4
That is definitely acme rods or known as trapezoidal rods too. I don't know how to tell the rod spec actually since it may come either metric or imperial. I'm sorry I don't know much about z axis rods supplied by sunhockey.

Maybe you could go a wee bit of a hard way, try printing in a layer height of .21-24mm and see the results

I'm sorry, I really do

I was just looking through the spec sheet on the site I linked and it says T8 lead screw, but I am not sure what I can get from that

3D Printer T8 300mm Z Axis Lead Screw 8mm Screw Pitch

Specifications:

Material: 304 stainless steel
Diameter: 8mm
Length: 300mm
Pitch: 2mm
Lead of thread: 8mm
Length: 300mm

Pretty much standard fare on fleabay.

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Viper97
3D Printer T8 300mm Z Axis Lead Screw 8mm Screw Pitch

Specifications:

Material: 304 stainless steel
Diameter: 8mm
Length: 300mm
Pitch: 2mm
Lead of thread: 8mm
Length: 300mm

Pretty much standard fare on fleabay.

So in the Optimal Layer Height Calculator on [prusaprinters.org] I am not sure what to select for Pitch Presets. I put in 2mm for Pitch, but dont see a T8 choice

I'm still confused on how the acme rods spec were used for example tr8*8-4 in here [openbuildspartstore.com] . There's not enough explanations about the short form version of specs, I guess your's is 2mm pitch

Seeing how good acme rods are, I am thinking of changing into it too but I should just try the anti backlash first

I'm guessing around 400 for the z-axis at a quick glance. That's what I've programmed mine for to start with the intent to adjust that number during calibration (Working on the Prusa I3 Steel).

If you calculate the lead and pitch (8*2=16) I believe that means that in one complete revolution of the motor the height will change 16mm.

Look at the stepper and driver. Mine has a 1.8° step angle with 32x micro-stepping Or 360/1.8 x 32 steps/rev = 6400 steps/rev so — 6400 steps/rev x 1 rev/16mm = 6400/16 steps/mm = 400steps/mm.

I'm probably wrong but this is what I found on the subject. Please correct me if I'm wrong.

Edited 3 time(s). Last edit at 08/11/2015 04:41PM by Viper97.

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Viper97
I'm guessing around 400 for the z-axis at a quick glance. That's what I've programmed mine for to start with the intent to adjust that number during calibration (Working on the Prusa I3 Steel).

If you calculate the lead and pitch (8*2=16) I believe that means that in one complete revolution of the motor the height will change 16mm.

Look at the stepper and driver. Mine has a 1.8° step angle with 32x micro-stepping Or 360/1.8 x 32 steps/rev = 6400 steps/rev so — 6400 steps/rev x 1 rev/16mm = 6400/16 steps/mm = 400steps/mm.

I'm probably wrong but this is what I found on the subject. Please correct me if I'm wrong.

I think you are right on. How do you I find out what my Micro stepping is?

A4498 = 1/16th DRV8825 = 1/32 Provided of course that all the jumpers are placed correctly (three jumpers per stick).

Edited 1 time(s). Last edit at 08/11/2015 05:24PM by Viper97.