Very interesting. Sugar has been used as a 3D printing medium. Could this be used as a water-soluble support for ABS?by Dale Dunn - Printing
This is definitely too large for timing belts to be lifting the beams in Z. A roller chain would be the thing. (Imagine a motorcycle or bicycle drive chain.) There's plenty of variety in sprockets and chains to choose from, all of it defined by standards and not proprietary. Worm gear reduction will minimize or eliminate power needed to hold position. This much weight will be a hazard, so plan aby Dale Dunn - General
I think all 3 terms have distinct meaning with overlapping skill sets.by Dale Dunn - 3D Design tools
For all the new printed parts and time invested in reassembling the printer, I think you'd get a lot more for your effort by converting to a Prusa i3.by Dale Dunn - General Mendel Topics
Looks like lost steps. Try a touch more current on the stepper driver. Maybe a slipping pulley. Not a calibration issue.by Dale Dunn - Printing
Things get a little larger when warm, so you need to do your Z axis homing when everything is at the temperature used during a print. However, if you're breaking hot ends on the print bed, you may be losing Z steps occasionally. You should probably adjust your Z axis mechanics to limit the force that can be applied downward. For example, the Z axis nuts can separate from my X axis ends if somethby Dale Dunn - General Mendel Topics
Sublime Wrote: ------------------------------------------------------- ... > If the friction in the Z axis is so great that it > will over come the position of the microstep in > favour of the whole step then having microstepping > enabled and using whole steps will not make it > better since at some times it will be in the > microstep position and sometimes it will be in the &gby Dale Dunn - Printing
3200 steps/rev? That must be 3200 microsteps per rev. You get 200 whole steps per rev, and on average those will have good position. The fractional steps are less reliable for holding position, so you get some thick layers and some thin as the stepper attempts to stop near to or far from a whole step. Huh. I got a different number for mm /rev. 12 tpi is 0.08333 inches/rev. Multiply by 25.4 to geby Dale Dunn - Printing
Do those bands wrap helically around the part or are the at the same level all the way around? If they're the same all the way around, then it's not Z axis wobble (though that may still be present and masked by a larger effect). Z banding that's not wobble is caused by slight over-extrusion or layer heights that aren't an even multiple of Z axis full steps. Fractional step positioning is not verby Dale Dunn - Printing
Or add a fan to help cool the stepper drivers. Check for loose pulleys too.by Dale Dunn - General Mendel Topics
Use a flexible coupling and make sure one end of the threaded rod is free. This way you don't need to worry about making a perfect alignment of screws which are probably not even straight. Also, make sure your layer height is an even multiple of a full step on the Z. Fractional step positions are not guaranteed on Z, and this is another cause of banding. But your prints look like you're losing sby Dale Dunn - General Mendel Topics
I think it could be done, but I don't think the added complexity is justified by keeping the machine small until it's printing. There are some pretty straightforward folding designs for portability, if that's why you want to keep it compact.by Dale Dunn - Mechanics
Old post, but just in case: The inverted printer may have some advantage regarding extruder ooze, but that's about it. The table on that machine is going to be very slow compared to the movements of almost any RepRap design. If you're working on the clock, spending a little to build a dedicated machine will save you money very quickly. A VF-0 is just way too big, strong, and slow for a printerby Dale Dunn - CNC Routers, Mills, and Hybrid RepRapping
The Z axis stopped moving after 20mm?by Dale Dunn - General Mendel Topics
Sticky screws? I seem to remember having lost some Z axis moves to unlubricated screws. Usually it would move, sometimes it wouldn't. Simple hex nuts on simple threaded rod will wear and cause random stickiness. Some places the steppers can get started, other places they can't. Once started, traversing the whole axis is relatively easy. I had some bicycle chain lube handy, so I ran some of thatby Dale Dunn - Printing
Layer height looks too high. The 0.35 nozzle should have layer height something like 0.2. Have your seen Prusa's calculators?by Dale Dunn - Printing
The 5/16-18 is preferable for the finer pitch and not being absurdly oversize, but your optimal layer heights will be an inconvenient size. The metric sizes give more sane optimal layer heights and don't contribute to the perpetuation of inch hardware. M5 or M6 can be coupled to the Ø5mm stepper shaft with just tubing and zip ties. M8 is actually a bit oversize and more likely to contribute to Zby Dale Dunn - Mechanics
You'll have to use Skeinforge if for some reason you have to a machine with backlash. Why can't you get rid of the slop?by Dale Dunn - Slic3r
Marco, what you dealt with is a general warping problem, not a problem of distorted overhangs on early layers. The overhangs Axis posted pics of would probably be fine if they were a couple cm above the bed.by Dale Dunn - Printing
New pics at .2 layers and .35 nozzle?by Dale Dunn - Printing
Are you printing at a layer height that is an even number of whole steps for your motor? Microstep positions are not accurate with a screw-driven Z axis (not sure about belt and cable systems on Rostock and Tantillus), so some layer heights will be too low, resulting in too much plastic for the real layer height.by Dale Dunn - Printing
The kinematics of your printer are not significantly different from mine (MakerGear Prusa). Assuming the same or similar electronics (RAMPS with little heat sinks on the stepper drivers), you should be able to turn the current up far enough to prevent lost steps. Since this is a new problem, you might look into whether your Y axis bearings need lubricated. Or perhaps even go so far as to check aby Dale Dunn - Printing
No mechanical downside for the size of most RepRap printers. It doesn't scale up too much without losing some performance to the mass of hte print bed. Incidentally, the first RepRap printer (Darwin) was configured as you describe. The Mendel design was developed in part to address some of the difficulties of that implementation of that configuration. Primarily, Mendel is a simplification. Myselfby Dale Dunn - Mechanics
Some of the slicers are filtering these moves now. Unfortunately, I don't remember which do. Other than that, you can try lowering max acceleration settings in your firmware. For whatever reason, I've not yet had to attach a fan to mine. So I can't offer any advice on how to best connect a fan. I should get around to that someday, so I can turn the current up and accelerate harder.by Dale Dunn - Printing
Only SW premium can do that.by Dale Dunn - 3D Design tools
Look like too much plastic, for starters. How did you calibrate your e steps per mm?by Dale Dunn - Printing
You don't show any evidence of a belt loose enough to skip teeth. Your stepper motor skipped some steps. From accelerating too hard. From short infill moves that result in resonance of the machine. This is similar to accelerating too hard. From the driver current being too high. If the current is too high, the driver's thermal protection will shut it down until the temperature recovers. THis cby Dale Dunn - Printing
This is caused by the extra heat coming from the platform. The same feature 15mm from the bed wouldn't be nearly as distorted. The layer can't cool fast enough with so much heat from below. A fan should help, but I've not yet bothered. So far, I avoid having more than about 30° overhang within about 10 mm of the bed. Of course, layers that don't have time to cool would have the same problem. Maybby Dale Dunn - Printing
billyzelsnack Wrote: ------------------------------------------------------- > Ask him about those links! Are those ball magnets?by Dale Dunn - General
To model warping with FEA, you'd have to run a new analysis for every layer, which would be time consuming to say the least. Results may not be accurate, because it ideally should be running the analysis every time the geometry changes, that is, with every finite amount of extrusion, based on a preliminary G code file. The output (whether by layers or threads) would then have to be sliced again,by Dale Dunn - General