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I'm wondering if your printer is set up with one axis backwards. Find a model on thingiverse with text (the LasVegas sign comes to mind), slice it and view the sliced model in pronterface. Is it reversed? Print it. Is it reversed?
by
raldrich
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Slic3r
j_andberg Wrote:
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> Hi Matt:
>
> The z axis turns only one way, and a fraction of a
> turn for each layer, at that.
Not any more - slic3r has a "lift" option, which raises Z by a fraction when retraction is needed, to combat strings.
There is also no
> idler. I was having trouble with the x belt having
> excessive fricti
by
raldrich
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General Mendel Topics
teru,
Your best toolchain is:
1) Any 3d software that can generate a manifold .stl file.
2) slic3r
3) printrun
4) marlin
I'm unsure if marlin supports techzone's thermocouple interface. With the "bit-bang" serial communications they used, most software engineers agree that it's a really bad idea, and most of the modern firmwares don't support it. You may find it easier to just invest in a th
by
raldrich
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Huxley
I think a "laser" optical mouse may be able to track unmarked filament - they do a fine job of tracking something as nearly featureless as frosted glass.
by
raldrich
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Plastic Extruder Working Group
I've been thinking about mounting an optical mouse camera (or two) onto my extruder, with the intention of using it to detect both missed steps, and slipping filament, so that both conditions can be reported in pronterface.
It occurred to me that with a bowden extruder, the same camera could be mounted at the hot end, and used to measure (and possibly correct) hysteresis, improving retraction.
by
raldrich
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Plastic Extruder Working Group
There are designs for a "sliced wooden" version of wade's extruder on thingiverse. The tricky part will be getting gears for it. Honestly, your best option would be to buy an extruder kit, either on ebay, or from a vendor.
Also, note that extruder kits usually don't include the hot end, so you might want to check out makergear's store.
by
raldrich
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Plastic Extruder Working Group
MakerBot MK7:
Length: 11mm
Outer Diameter: 12.5mm
Hob Diameter: 10.65mm (Smallest diameter at the tops of the teeth).
Hob Center: 7.45mm (Measured on the lock-screw end of the wheel).
Bore: 5mm
Arcol 11x5:
Length: 13mm
Outer Diameter: 11mm
Hob Diameter: 9.1mm (Smallest diameter at the tops of the teeth).
Hob Center: 9mm(Measured on the lock-screw end of the wh
by
raldrich
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Plastic Extruder Working Group
If adjusting the pots doesn't get you a comfortable motor temperature, you need to look for possible causes.
First, disconnect the belt, and see how smoothly the Y axis moves. If it's difficult for you to move it, then loosen up the smooth rod mounts, and reposition them so that it's easier to move.
If it moves smoothly and easily, then look at the firmware settings - acceleration could be set
by
raldrich
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Huxley
I went with a different approach on mine - since all of the horizontal threaded rod was cut longer than necessary, I made my frame an extra 15mm wide. Makes getting the full 200mm print width fairly easy.
by
raldrich
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General Mendel Topics
miso Wrote:
> All of those are multiplatform, so running any of
> them on Linux can be just as much "windows habit"
> as running Google Sketchup.
There's a world of difference between running a multi-platform application, and running a Windows application under Wine. The multi-platform application is designed to run in the environment that it was compiled for. The Windows application
by
raldrich
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General Mendel Topics
Z stabilizers only make sense if your z screws are perfectly straight - in which case, they're there to fix the bad alignment in your coupler.
A better approach is to use a more flexible coupler, and thinner (more flexible) leadscrews.
I have two printers, both of which use aluminum flexible couplers. One of them uses 1/4" acme leadscrew, and the other uses 5/16 threaded rod.
The one which us
by
raldrich
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General Mendel Topics
Double-check the pulley. With the motor powered, is it easy to turn the pulley a small amount back and forth? If so, tighten the set screw.
Double-check your belts. They should be tight enough that when plucked, they make an almost musical note (think bass guitar).
With the motor turned off, slide the carriage back and forth and feel for tight or rough spots. If the axis rods aren't perfect
by
raldrich
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General Mendel Topics
Either backlash or missed steps can make it very difficult (if not impossible) to calibrate.
For measuring backlash, LashMaze is quite useful.
For calibrating X and Y, I print a 100mm x 100mm x 1mm hollow square, and then measure it both for distance and for square, while it is still on the printbed, and before it has too much of a chance to cool.
For calibrating the extruder, I remove the noz
by
raldrich
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General Mendel Topics
Tom,
You might check to make sure that your hot end's melt chamber is clean. I've had a buildup of cooked plastic on the walls of the melt chamber produce similar problems.
by
raldrich
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Plastic Extruder Working Group
A word to the wise - before investing in any prebuilt printer or printer kit, log in to the #reprap IRC and ask for opinions about the vendor and their products.
by
raldrich
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General Mendel Topics
@Lanthan:
In the context of the original post, your stance on bridges is an overreaction, although I agree with you that not all of PrusaJr's changes to the design were well advised.
My concern about the Prusa parts repository is that more and more it requires a finely tuned printer and highly knowledgable operator to print usable parts.
In particular, the "Friction fit" x-ends can be tremendo
by
raldrich
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General Mendel Topics
nefermu Wrote:
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> Is it possible to use extruded Al structure with
> prusa electronics, software, firmware, etc ?
MendelMax is a Prusa, redesigned with aluminum extrusion. Electronics, software, firmware, and the x-axis all can be moved from an existing mendel (Sells or Prusa) without modification.
by
raldrich
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Extruded Aluminum Frames
martinprice2004 Wrote:
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> I think the part is supposed to be printed with your bridging
> parameters adjusted correctly, so the printer speeds up across the gap eliminating the sag.
To adjust the bridging parameters, you need to reduce Speed/Bridge Feed Rate until the ends of the bridge filaments adhere properly, and then reduce Speed/
by
raldrich
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General Mendel Topics
If it's clogged with ABS, you can clean it out by soaking it in acetone.
If it's clogged with PLA, you can clean it out by soaking it in caustic soda (Lye, drain cleaner, etc...).
Of course, you should remove any PLA or ABS parts from the nozzle before soaking it.
by
raldrich
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General Mendel Topics
One concern will be that whenever you're extruding, you're imposing a rotational force around the axis of the feed roller, which could easily cause our cheap linear rails to flex and/or bind. Even if it doesn't cause binding, it's likely to cause the nozzle to move horizontally, at least a tiny bit.
by
raldrich
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Mechanics
I ran into the same issue, I suspect that there's an older version of OpenSCAD that works, but the latest one doesn't like to import it's own work.
Looking through the sources, it appears that there are many places where the subtractive geometry is exactly the same size as the additive geometry, which can cause those kinds of errors.
by
raldrich
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General Mendel Topics
criswilson10 Wrote:
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> Linear bearings work better than bushings, but they also usually cost 10x more.
That isn't necessarily true. In my experience, LM8UU linear bearings wear out, and become quite noisy after a short period of time, while IGUS bushings wear quite slowly.
If you were referring to v-groove style linear bearings, then I'
by
raldrich
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Mechanics
I think that answers the question as to why they were so noisy. You need to assume that they're completely unadjusted, and turn the current down before you power things up.
by
raldrich
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Huxley
6/32 SAE nuts apparently don't have a standard size. I've got 2 of them here with different outer diameters. A small one that measures 5.4mm across the flats, and a larger one that measures 7.88mm. Go figure.
by
raldrich
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General Mendel Topics
It sounds to me like you've got all of the electronics you need for a SphereBot, a 3D scanner, or a laser engraver.
by
raldrich
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General Mendel Topics
I was having a tremendous amount of trouble with part strength, and eventually tracked it down to a bug in sfact. Under certain circumstances, it was retracting more than it was replacing. This would happen more often in the infill, but sometimes also exhibited as gaps in the exterior shell.
Updating to the latest sfact daily, and switching to the "Olddimension" module resulted in much stronge
by
raldrich
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Plastic Extruder Working Group
billmi Wrote:
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> It seems to me a hardwood like cherry or oak would
> do well - cheap and easily available in block or
> rod, low thermal conduction and good heat
> tolerance.
TechZone tried that approach - the problem is that oak is shot through with little pores, that allow plastic (Particularly PLA) to permeate the part. Once
by
raldrich
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Mechanics
From a legal standpoint, nothing is food safe, unless it is documented as food safe.
From a practical standpoint, you can't trust colored PLA to be food safe, because you've got no idea what dyes and binders were added to it.
You might argue that natural PLA would be food safe, except that you can't guarantee that the guy who extruded the filament didn't just finish cleaning his extruder with M
by
raldrich
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Polymer Working Group
It'll probably be another week before I'm ready to post another sale. I need plastic to show up before I can start the next set (I used up my ABS supply with the last set).
by
raldrich
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Plastic RepRap Parts for Sale
DeuxVis: TechZone's tip manager ended up being one of those fantastic ideas that turned out to be seriously flawed. The problem isn't the hardware, it's that the serial communications between the extruder controller (or monolithic board) and the "tip manager" are very poorly written.
It takes 40ms to read the temperature from the tip manager, and for most of that time, the "OneWire" library tha
by
raldrich
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Huxley