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Layer height as an integral number of Z steps - 2 years ago

Hi, Not really a reprap question, but I'm not sure where else to ask... I'm trying to get the absolute best possible quality print for a project on my Creality HALOT ONE resin printer. It occurs to me that (as with XYZ FDM printers) it would be better to set the layer height as a value that equates to an integral number of steps of the Z stepper motor. e.g. if Z steps are 880/mm (1 step = 1/880m

by frankvdh - Printing

Re: Get a PhD for doing RepRap Research - 3 years ago

What's fully funded in terms of monthly stipend? Enough to live on comfortably?

by frankvdh - General

Re: Hotend Heating Failure - 3 years ago

Quotefelystar When I used a multimeter to measure the voltage on the RAMPS hotend connection something weird happened, because the temperature started increasing and the printer worked well. I managed to print the radial fan adapter again using the mounted radial fan I printed at the beginning. However, when I went back to do another print right after this one finished, I started getting the sam

by frankvdh - General

Re: linux command line conversion of .stl to a 2d image? - 3 years ago

OpenSCAD can be run from the command line, and provided with a script that reads an STL file and even rotates and positions it. I don't know if you can get it to save a screenshot. However, I think you could have a Java (or whatever) program read an STL, generate the script for OpenSCAD, run OpenSCAD, and then take a screenshot.

by frankvdh - General

Re: Any clever technique to detect bowden problem before blowout? - 3 years ago

The Bowden connectors are really pneumatic tube connectors. They certainly shouldn't pop out under pressure. Check that the little plastic piece is lifted up... pressing it down releases the teeth in the connector to remove the tube. Some people use a small spacer under the tab, because it might get pulled down and release the tube when printing. It might also be that the teeth have ripped up t

by frankvdh - Mechanics

Re: New printer problems - 3 years ago

Try using the M119 command to read the endstop states. (Assuming Marlin Firmware).

by frankvdh - Reprappers

Re: Extruder gear slips over the filament - 3 years ago

If the motor is turning and filament is not moving (or moving intermittently) and the motor is NOT cutting a divot in the filament, then you don't have enough tension on the extruder spring. When it is adjusted properly, it will leave small tooth marks in the filament. NB that too much tension is also bad. However, there can be a multitude of reasons for the feed to jam... your hot-end is too ho

by frankvdh - General

Re: Valved Bowden - 3 years ago

Quotethe_digital_dentist How does it add control? I believe the concept is that the lost control due to drag and bending inside the bowden tube is regained by including a small stepper at the extruder. This seems reasonable to me. When you push filament into a curved bowden tube, some of the force you apply goes into bending the tube, and the bending allows more filament to be inside the bowden

by frankvdh - Plastic Extruder Working Group

Re: 5v laser and other questions - 3 years ago

OK... I'm at the limit of my electronic knowledge here. I don't know what kind of laser diode drivers these cheap Chinese laser modules have. But I do know that the one I bought (and they all appear to be the same) described the 5V input as "TTL". And I do know what that means. Just trying to save the OP from destroying his device.

by frankvdh - Firmware - Marlin

Re: 5v laser and other questions - 3 years ago

QuoteVDX .The power is defined by pulse-length - so 0-5V analogue input to my drivers "set power"-input will result in pulse-lengths from 5 to 500 Milliseconds ,,, The input isn't analogue in the voltage domain. It's digital (TTL)... 0 or 5V. The analogue aspect is, as you say, in the time domain (PWM). The OP was talking about generating a 5V signal by using PWM to modulate the 12V fan output a

by frankvdh - Firmware - Marlin

Re: 5v laser and other questions - 3 years ago

There is a 5V TTL signal that drives the transistor that switches 12V for the fan. Use that as the TTL input to the laser. Do not use PWM to approximate 5V.... this will generate a 0-12V square wave which will probably destroy the TTL circuitry in the laser. FWIW, I have an AliExpress "5500mW" laser. It will run at full power for maybe 5 minutes of normal on/off use. After that it intermittentl

by frankvdh - Firmware - Marlin

Re: Quick change hotend - 3 years ago

QuoteAndy1989 Printermods have just released a kickstarter for a quick change tool head that does exactly what I'm looking for! Yeah, but you can buy an entire 3D printer for the price of one of their quick-change heads.

by frankvdh - General

Re: Why you should power off when unattended - 3 years ago

Yeah, but this failure wasn't due to poor heat dissipation. There had to be a pretty good short circuit to peel up a layer of the board. And, as I said, this was the Z stepper on a laser cutter, so not actually doing any work.

by frankvdh - Safety & Best Practices

Why you should power off when unattended - 3 years ago

This was the A4988 Z stepper driver on my laser cutter as I found it after cutting. My control board is, as recommended by the manufacturer, mounted vertically on the gantry, not covered at all. When I replaced this stepper driver, everything worked as usual, so no fuses were blown. NB that the Z stepper is only used for focussing before cutting, not at all during the cutting operation. So I g

by frankvdh - Safety & Best Practices

Re: Extruder temp drops while printing - 3 years ago

Those axial fans are better at sucking than blowing. For blowing, you want a radial fan.

by frankvdh - Printing

Re: Extruder temp drops while printing - 3 years ago

Yes, the radiator cooling fan can just be wired direct to the power supply. There's no benefit (apart from noise) in turning that off. Ideally you want fine (about the same size as the extruder nozzle) jets of air aimed at the tip of the nozzle to cool the filament to solid as soon as it is extruded. Ideally, you want those air jets to be able to flow away freely to take the heat away.. You mi

by frankvdh - Printing

Re: Look for the best information - 3 years ago

There are far too many practically unprintable objects out there. (It used to be same with programming... every high school kid and lab technician and salesman would create programs that *almost* worked, but were so fundamentally flawed and impenetrable that they were never going to ever work). So, as a general rule, I never print something if the designer doesn't have a photo of the actual print

by frankvdh - Printing

Re: Extruder temp drops while printing - 3 years ago

Do you have a part cooling fan that is perhaps blowing on the nozzle or heater block? What happens if you pause the print? Does the temperature rise again? Another thought (although you seem to have already covered it) is that there's a bad connection somewhere in the heater wiring, so there is intermittent power supply to the heater as the hotend moves around. Can you put an LED in parallel wi

by frankvdh - Printing

Re: Quick change hotend - 4 years ago

That's interesting. What I do nowadays is to use 2 4-pin connectors for the hotend... one for thermistor and heater, the other for fans. This is more to make it easy to unclog or otherwise work with the hot-end than anything else. I have opposite gender connectors on each connector so I can't accidentally plug the fans into the heater/thermistor. The fans could probably be serviced by a 3-pin co

by frankvdh - General

Re: My 6 input (5+1) mixing hot end - 4 years ago

Quoteleadinglights I see that you use cable ties to hold your silicone tubing as I used to untill I found that I had to cut off the cable tie every time I released the pipe. I have some releasable cable ties

by frankvdh - Developers

Re: Help Needed - Custom Built 3d Printer - 4 years ago

QuoteBalajiS 1. Still Y Axis after few hours moves/Jitters slowly in diagonal... When things go wrong after a period of time, usually the problem is heating or cooling. If your Y axis motor or (more likely) stepper driver is overheating, it will skip steps and make the horrible graunching noise you describe, and of course the carriage won't move in that axis, or only move in one direction. Try h

by frankvdh - General

Re: Patents - 4 years ago

QuoteVDX ... the original intent of patents was to avoid double- or multiple-inventions worldwide, while the essential invention and infos around were already known otherwere. Patents were never and are not worldwide. They are on a country by country basis, and you cannot get a worldwide patent. You need to get a patent in every country where you want protection from copying. However the Patent

by frankvdh - General

Re: Filament measuring thingy - 4 years ago

An idea I have for a post-retirement project is to use capacitance to measure the cross-sectional area of filament. People may be aware of capacitance fuel gauges, which are common in cars nowadays. The principle on which they work is that the capacitance between two plates varies depending on the dielectric of what's between and around the plates (theremins are similar). In the article I read, t

by frankvdh - General

Re: Patents - 4 years ago

If you have an idea you want to patent, go for it. I'm cynical... a patent is only as strong as the owner's ability to defend it. So a wealthy corporate who wanted to rip you off could do so with impunity. You probably can't defend your patent against infringements in (say) China. As well, patents used to be a way of rewarding people for creative ideas by granting a temporary monopoly. Nowadays

by frankvdh - General

Re: PrintHero SLA 3D printer - 4 years ago

Lots of other people are picking apart PrintHero in the KickStarter campaign comments, so I'm satisfied it's a scam. Stay Away!

by frankvdh - General New Machines Topics

Re: Tablet Based LCD Printer - 4 years ago

My understanding of SLA is that the Z resolution is the thickness of the layer of resin on top of the screen. So you want as thin a layer as possible. The resin is cured by the light emitted by the screen (I guess there's some film on the screen to stop the curing resin from sticking to it) so if you clamp the screen to the bottom of the tank, *all* the resin above the screen will get cured, with

by frankvdh - General

Re: Thingiverse taking it's last breath? - 4 years ago

QuoteOhmarinus I have already coined the term 'palliative care' for Thingiverse, they responded to that one by saying it's not true, but we can all see that it's already rejected and only maintained on a really low level. The cancer of human commoditisation is spreading to TV. Hence the need for people to be logged in to be identifiable. The designers who are the source of TV's value are also

by frankvdh - General

Re: PrintHero SLA 3D printer - 4 years ago

QuoteVDX ... looks like a bigger variant, compared to the common much cheaper "smartphone-display-printers" ... Yeah, except it has a built-in UV LED panel, so uses resin cured by UV rather than visible light. AliExpress sells the same thing (more or less) for about 4 times the price.

by frankvdh - General New Machines Topics

PrintHero SLA 3D printer - 4 years ago

I'd appreciate the views of knowledgeable SLA 3d printer users on this project on KickStarter. It seems like a great deal. Having been bitten once by the ONO/OLO dog, I'm suspicious... at the price and performance, it seems *way* too good to be true. There's also a couple of other red flags that I'm uncertain about, so I'll keep them to myself for now. Opinions please!

by frankvdh - General New Machines Topics

Re: 3D printer hacking (Gcode help needed) - 4 years ago

You don't say what firmware you have on your printer. The interpretation of G-code depends on your firmware. See for a good description of all the G-code commands in all the common firmware versions. QuoteDust "Allow fine control of the extruder motor independently of any movement, and disable all security check that go with it." Can't do it, its 3d printer firmware, this is part of its soul.

by frankvdh - Developers