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Discuss any sort of mechanical stuff here: positioning systems, gears, extruding methods, etc.
Re: Differences between types of extruders - 11 years ago
@Pacca, The problem with the motor that you linked is that they're rather cheaply built, with sintered bronze gears, and have 2 failure modes. The first is that if you use the same acceleration settings that you would use on a Nema 17 motor, one of the small bronze gears will break when retracting or replacing filament. The second (and IMO, worse) is that in some of the motors, the interferencby raldrich - Plastic Extruder Working Group
Re: 3mm hobbed bolt and extruder with 1.75mm filament? - 11 years ago
Polygonhell Wrote: ------------------------------------------------------- > I'm using a standard Wades extruder and a generic > hobbed bolt on 1.75mm filament without issues. > Unless the bolt is hobbed so deeply the filament > doesn't touch the idler, I can't really see how > it's an issue. It can be an issue if the extruder body is designed with tight clearances for the filamenby raldrich - Plastic Extruder Working Group
Re: Direct drive extruder - 12 years ago
For 3mm filament, you'd do better with a gearbox motor such as (Nema 17 stepper) or (tin-can stepper)by raldrich - Plastic Extruder Working Group
Re: Introducing Akimbo - a redesign of the Mendel. - 12 years ago
The extruder is currently a minor variation of my RCX extruder, which uses a stepper motor with a built-in planetary gearbox, drives the filament using a 12.7mm hobbed wheel, and is well documented on Thingiverse. I'll soon be modifying the extruder's design to use this stepper instead, as it has a stronger, metal gearbox, is electrically a better match for the drivers and voltages that we use,by raldrich - General Mendel Topics
Re: asking for rail binding opinions - 12 years ago
I've found that even with LM8UU bearings, a high degree of accuracy in the linear rods is necessary - they'll move if your rod isn't well aligned, but they'll wear out quickly and/or cut grooves in the rods. On my latest build, I've used a hybrid approach - LM8UU (or printed equivalents) on one rod, and a pair of roller bearings on the other rod. With this arrangement, precise alignment of theby raldrich - General Mendel Topics
Re: Oversize Mendel Prusa - 12 years ago
QuoteI'd like to see a derivative that has either only one top bar or wider spaced bars.by raldrich - General Mendel Topics
Introducing Akimbo - a redesign of the Mendel. - 12 years ago
Thing, (and thingiview) at Sources at Akimbo is a redesign of the RepRap Mendel, designed with increased build area, dual extrusion, easier assembly and increased rigidity in mind. Things to like about it: 1) If you opt for a single extruder, it's easier to attain the full 200x200 build area, than on previous designs. 2) Taller build height - if you limit X travel at the top, the eby raldrich - General Mendel Topics
Re: RepRap it's self going commercial, too? - 12 years ago
Quotejohnrpm One of the main things that attracted me to the Reprap community was, Wealth without money although I don't see it so much now, I think we should be in either of two camps, open source/hardware or commercial, keep reprap or a new foundation for open source/hardware and let others who want to be commercial go some place else. If all of the reprap designs were licensed for non-commerby raldrich - General
Re: tech zone - 12 years ago
Their website has been down for months, so if they're still in business, it's under a different name. As for support - there's plenty of folks in IRC ( ) that can help. For myself, I'm happy to say that the only parts that remain of my TechZone (laser cut) mendel are motors, rods, nuts and bolts - nothing that they actually manufactured remains.by raldrich - General
Re: new thingiverse update from attorney - 12 years ago
QuoteRegardless, I hope that this issue dies down because I can't imagine there is a truly satisfactory outcome for all. I don't believe MBI are being malicious, simply that they haven't been very good at interacting with the community on this issue. I agree with you - imo, the clause in question probably was written by the most junior of partners at MakerBot's law firm, and should never have paby raldrich - General
Re: Can I print my own timing pulleys? - 12 years ago
The most common source of backlash on a printer is having the printed timing pulley work loose, and start spinning a bit on the shaft. Believe me, the cost of manufactured pulleys is worth every penny.by raldrich - General
Re: Polycarbonate printing - 12 years ago
Personally, I consider my own outgassing and decomposition products to be more hazardous.by raldrich - Polymer Working Group
Re: Prusa Jr. Chastises & Leaves THINGIVERSE >
< - 12 years ago
For those of you who haven't been following the discussion, the issue is with Section 3.2 of the new TOS; in particular, the last sentence. QuoteYou agree to irrevocably waive (and cause to be waived) any claims and assertions of moral rights or attribution with respect to your User Content. The upshot of this is that Thingiverse (and MakerBot) are attempting to give themselves the right to doby raldrich - General
Re: Techzone Huxley redesigned / modified parts. - 12 years ago
From what I can tell (trying to visit techzonecom.com) - they're gone now anyway, but DuexVis is right - RAMPS, Sanguinololu, Teensylu, or Printrboard are all far superior electronics.by raldrich - Huxley
Re: Techzone Motor runs HOT - 12 years ago
The only thing I can think of on the board which can cause a motor to always run hot is the adjustment pot. It's possible that it just isn't working, and current is never being limited - or, it's possible that you simply haven't turned it down far enough. If there's no setting for the pot where the motor stops turning at all, then the pot isn't working - resoldering it may help.by raldrich - Huxley
Re: Source of 8mm rods - 12 years ago
I found that MicroTek flatbed scanners were my best source for scavenging 8mm precision ground smooth rod. Each one contains a single (approx 400mm) length of 8mm smooth rod, which appears to be stainless steel (non-chromed), ground to better precision than drill rod. You'll also get a small power supply, some fairly useless electronics, an optical endstop, glass and switches. The glass is tapby raldrich - General Mendel Topics
Re: Fabbing a Circuit Board with Electrodeposition - 12 years ago
I normally wouldn't suggest chinese plastic, as it doesn't seem to print particularly well, but is a conductive ABS, which might conduct well enough to copper plate.. Soldering to it would be an entirely different problem.by raldrich - Plastic Extruder Working Group
Re: thereprapkitstore.com Prusa Mendel construction Notes/Discussions - 12 years ago
I've never thought that using a "thin wall" object to calibrate extrusion was a particularly good plan. What you really want to know is exactly how much plastic is going into the extruder, and to know that, you need to calibrate your extruder's steps/mm so that when you tell the extruder to feed 100mm of plastic, exactly 100mm of plastic goes in (I usually do this with the hot end off, so that Iby raldrich - General Mendel Topics
Re: how to affix makergear hot end? - 12 years ago
If you want something more substantial than wood, Hotends.com sells an aluminum mounting plate.by raldrich - Plastic Extruder Working Group
Re: thereprapkitstore.com Prusa Mendel construction Notes/Discussions - 12 years ago
jonathanbyrn, If your extruder's drive motor is mounted directly on the carriage (rather than on the end of a cable as in a bowden extruder), then extra length on restart should be zero. Paint a mark on your extruder's main gear, and watch it carefully as it retracts and replaces the plastic. If it doeesn't replace as much as it retracted, then reduce your retraction speed (in slic3r, sfact orby raldrich - General Mendel Topics
Re: SAE configuration file? - 12 years ago
I think mostly because the people who maintain the github don't live in either of the two countries that still use SAE measurements, and have learned to strongly discourage the use of SAE parts.by raldrich - General Mendel Topics
Re: Botmill and the end of the world. - 12 years ago
There are certain phrases that I cringe to see in IRC - "I bought a kit" is one of them. The issue is that the people who are making the kits assume that the people who are buying the kits bought a kit only because they didn't want to spend the time tracking down the parts themselves. Once you make that assumption, then leaving out documentation follows naturally - "It's a Prusa kit - use the Pby raldrich - General Mendel Topics
Re: sae prusa mendel which stl github files to use? - 12 years ago
The latest sources for the prusa in github don't distinguish between SAE and metric - instead, they are designed to work with either. I suggest, however, that you avoid 5/16 smooth rod, and spend the extra couple of dollars on metric smooth rod - you'll appreciate why when you price 5/16 linear bearings vs 8mm linear bearings.by raldrich - General Mendel Topics
Re: Slic3r and J-head hotends - 12 years ago
Sublime Wrote: > I have found almost the exact same thing. I am > using the flow rate modifier in Marlin which > reduces the steps per mm on E and it is really > obvious when you change layer heights. With slic3r 0.8.4, I tried the obvious experiment, and sliced a 40mm cube with no skirt, and 100% infill, at .1 layer height, and .25 layer height. Both reported a filament requiremenby raldrich - Slic3r
Slic3r 0.8.4 support reactions - 12 years ago
I just tried using support on one of my "basket case" models, and have some reactions: 1) Rectilinear support created a comb like structure, with none of the teeth of the comb supported by anything except their connection to the print bed. The drawbacks to this are: a) The "Teeth" of the comb were entirely unsupported, which resulted in some of them being knocked over by the print head. b) The fby raldrich - Slic3r
Re: [project] Heavy mendel, a self replicating 3Dprinter/mill/PCB engraver - 12 years ago
Quote- Precision doubling belt configuration inspired by Madkite's design : You should test it with and without the block-and-tackle pulley design. The consensus in IRC is that the added complexity of the design, additional belt length, and increased friction, is likely to introduce more backlash than the added mechanical advantage will remove. So far, that's all just opinion, because I haveby raldrich - General New Machines Topics
Re: theories on sticking/not sticking? - 12 years ago
Buback Wrote: ------------------------------------------------------- > Why does the plastic stick to a heated bed and not > at cold bed? (like nophead's experiments with > glass beds) > > Another critical property is ease of release. > > Has anybody tried a coated bed? I'm envisioning a > spray on coating that adheres to the bed and > plastic (perhaps with differentby raldrich - Polymer Working Group
Re: What to look for in a hot end? - 12 years ago
1.75mm Pros: Requires less torque, so works with a direct drive (gearless) extruder. Requires more steps/cubic mm of extrusion, so produces more precise extrusion. Cons: Costs more (by volume) than 3mm filament. With a bowden extruder, print quality is compromised because the filament is springier. Personally, I use 3mm filament, and see no reason to pay tby raldrich - Plastic Extruder Working Group
Re: warning: don't buy cheap motors for your reprap! - 12 years ago
Sounds your acceleration or speed settings are too high for them.by raldrich - General Mendel Topics
Re: Mini Hyenas - 12 years ago
Once Arcol's finished shipping the indigogo hyenas, he'll be adding them to his webstore.by raldrich - Plastic Extruder Working Group