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Moineau stepper extruder - 12 years ago

Hello everyone, I'm currently developing a paste extruder based on the Moineau pump principle. In theory that design should work well as an extruder, as it has completely non-pulsating output and can pump pretty much anything. Running it with a stepper motor should allow controlling the extrusion just like in a hot plastic extrusion head. Here's what I have so far: Exploded view. From the bottom

by ttsalo - Paste Extrusion Working Group

Re: Thoughts on Fill Algorithms - opinions welcome - 12 years ago

I think that designing uniform fill patterns is a dead end. What really is needed is a fill pattern with continuously variable density. That way you can have very sparse infill inside large hollow spaces and have it become thicker and stronger near stress points. Many designs programmed with OpenSCAD have a ton of sharp angles produced by the combining of primitive geometric shapes with CSG, an

by ttsalo - General

Re: SF41 producing mystery 100% infill layers - 13 years ago

Thanks for the advice! Turns out it was the "infill in the direction of bridge" setting in the Carve tab. I increased perimeter shells to ridiculous amounts (20) but still got the mysterious 100% infill layers with just one perimeter shell. Turning off the "infill in the direction of bridge" got rid of those and produced the expected sparse layers with still partial full infill in the areas where

by ttsalo - Skeinforge

Re: Different nozzle shape = long slot? - 13 years ago

jbayless Wrote: ------------------------------------------------------- > There's actually no need for a servo, if you use > two print heads and are willing to lay down > parallelograms instead of squares. I mentioned > idea like this a while ago but I haven't tested it > yet. Hoping to get around to that this year... But if you're going for two print heads, why not just have two

by ttsalo - General

SF41 producing mystery 100% infill layers - 13 years ago

So I printed Yoda and he ended up pretty ugly... One problem was that Skeinforge produced lots of unnecessary 100% infill layers. These appeared in groups of 2-8 and had only one perimeter shell each. I couldn't see any logic to when these appeared. Sometimes there was lots of overhang at the same level but sometimes not. Also the fill direction didn't rotate like on the usual solid surfaces. O

by ttsalo - Skeinforge

Re: Does RepRap Assemble Itself? - 13 years ago

sarahsliefie Wrote: ------------------------------------------------------- > Johnyradio, what is your goal with this rant? it > seams a bit confused. Are you wanting to point out > that we have not reached that goal stated on the > web page? Is it to point out the evils of possible > self replication? All you seam to do is point out > that we have not reached that one goal yet.

by ttsalo - Developers

Re: Constant high-speed printing - 13 years ago

richrap Wrote: ------------------------------------------------------- > I read back Nopheads blog post on Knurled v > Hobbing and it may actually be worth using > Knurling rather than hobbing when you use a bigger > drive wheel, the contact area will be much greater > and as long as you can apply idler pressure across > a section or a few points the knurling may cause > less

by ttsalo - General

Re: Mendel-parts Gen 6 'Marlin' firmware feedback - 13 years ago

droftarts Wrote: ------------------------------------------------------- > Hi ttsalo. Could be the extruder motor skipping > steps, or like Buback says, the filament is > running through the heater so fast that it isn't > staying hot enough. Turn up extruder potentiometer > and/or increase temperature. Could also be the > gcode not transferring fast enough - I'm thinking > ab

by ttsalo - Firmware - experimental, borrowed, and future

Re: Constant high-speed printing - 13 years ago

nophead Wrote: ------------------------------------------------------- > Are these numbers real or is the acceleration > limiting the max speed to nowhere near that? I > find them hard to believe. I have no idea about the ridiculous 1000+mm/s numbers, but I did some test prints at 150mm/s and here's a video: 150mm/s with Orca and Marlin I checked the timing from the video and when the

by ttsalo - General

Re: Mendel-parts Gen 6 'Marlin' firmware feedback - 13 years ago

I also found some problems. Trying to print this Kort nozzle at 150mm/s speed caused the extruder to just sputter uselessly when trying to print the round part. At 50mm/s it worked perfectly fine. I don't know why it didn't work at 150mm/s, the curve is pretty gentle and it should be able to run the extruder pretty much at constant speed while tracing it?

by ttsalo - Firmware - experimental, borrowed, and future

Re: Mendel-parts Gen 6 'Marlin' firmware feedback - 13 years ago

It's really nice, so much smoother than the FiveD firmware... Here's a video I made of it printing pretty fast: Orca with Marlin

by ttsalo - Firmware - experimental, borrowed, and future

Re: Orca review - 13 years ago

Traumflug Wrote: ------------------------------------------------------- > How is it about rigidity? Is this Orca thing > stiffer or even weaker than a Prusa/Sells Mendel? > I'm asking, because I'm always after an machine > capable of hooking up a Dremel-like tool, for > replicating PCBs. A fresh Orca user reporting here. I have no experience with other RepRaps, but the rigidity o

by ttsalo - General New Machines Topics

Re: [Slightly off-topic:] Wealth without money? - 13 years ago

The first-world nations are already far on their way from the industrial to the post-industrial age, with three quarters or more of both workforce and GDP being in the services sector (i.e. not in the production of material goods). In the future that share is only going to increase. The real battleground is going to be in the intellectual property, not the Marxian physical "means of production".

by ttsalo - General