print quality issues

My reprap has terrible quality. It seems to print way to much plastic and squishes everything down. I started getting better results with the extrusion multiplier set to 0.65 but that's really low and sometimes there isn't a constant stream of filament. I've noticed that even though I click to raise the extruder 1cm or 10cm or what ever, it never reaches the specified amount. Could this be because I had to use standard threaded rod and not metric? I really need my printer up and running with good accuracy (I know it's a rep-rap but it should be better than what I'm getting) Any body willing to make suggestions feel free but I really need someone that can email me on a constant basis to help me out a lot as I go through. Specific details of the printer can be provided if needed

Here's what I'd do in your situation.

First, I'd make sure all the mechanical relationships in the machine were right. That means making sure the frame is bolted tightly together, belts are tight, moving parts are moving freely throughout their allowed ranges, pulleys are firmly attached to motor shafts, etc.
Next I'd check the wiring and make sure everything is connected properly with adequate gauge wires, etc.

Once I'm sure the machine is set up to function properly from a mechanical and electrical standpoint, I'd start modifying the firmware in the controller to match the machine's capabilities. You have to set maximum speeds, accelerations, build envelope, motor current and steps per mm in all three axes and the extruder, temperatures, endstop function, etc., the method of which depends on the controller/firmware you are using.

Have you done any of this yet?

Edited 1 time(s). Last edit at 02/28/2015 07:36AM by the_digital_dentist.

I have gone through the basic set up in the sprinter file on the arduino interface. I haven't gone through the entire program to change every tiny thing only because the set up of my printer didn't require yet. I'll go through the whole thing later today. I'm also having a layer strength problem, most of the layers aren't bonded very well. Is this a temperature issue? Thanks for the help

Quote
Trexter67
My reprap has terrible quality. It seems to print way to much plastic and squishes everything down. I started getting better results with the extrusion multiplier set to 0.65 but that's really low and sometimes there isn't a constant stream of filament. I've noticed that even though I click to raise the extruder 1cm or 10cm or what ever, it never reaches the specified amount. Could this be because I had to use standard threaded rod and not metric?

Regarding the Z movement, if the threaded rod you are using is not the same as the design called for, you can adjust the Z steps/mm to compensate. Another possible explanation for the reduced Z movement is that you have the Z acceleration or Z max speed set too high.

The reduced Z movement, if it is causing the layers to be thinner than commanded, also explains the apparent-over extrusion. But you may have the extruder steps/mm configured too high. Have you calibrated it?

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

If you haven't calibrated the machine you will naturally have all sorts of printing problems and they will continue until you calibrate the machine. Calibration includes adjusting motor currents, setting maximum speeds and accelerations, steps/mm for all axes and the extruder, running PID autotune for the bed and hot-end, limit switch functions, bed leveling and zeroing, etc. You may find that most of the problems will magically disappear after you calibrate. If they don't, post here for assistance.

Can someone help me with the calibration? I'm great with building the thing and making it work but the fine tuning and computer adjustments are not my specialty

Well, after a few YouTube videos and some Googles. The results ate great! Thank y'all