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Salute to the Moderator, and a Happy New Year - 16 days ago

Be well, be inventive, be thoughtful.

Re: Wrong Z height after long print, Z-shifting - 5 months ago

Interesting. I've recently noticed that the latest bugfix prints all of the axes on a 1 inch test cube 0.008 inches (0.200mm) too big. Reverting to a bugfix from April 2023 makes the problem go away.

Re: Bed temperature offset and stabilization - 5 months ago

QuotePCLoadPLA I confirmed the temperature with a bimetallic hot-plate thermometer as well...I trust it, but it responds very slowly so I had to use the IR gun to measure the stabilization. If the thermistor were in the aluminum, instead of the heater, the PID control should compensate for at least some of the offset and "lag" between the heater and the top of the aluminum. For now I will just

Re: Bed temperature offset and stabilization - 5 months ago

What you describe is not only common, it's unavoidable physics. You are heating a 1/4 inch thick aluminum plate from the bottom while it radiates heat into the environment from the top. Because there is no such thing as a perfect thermal superconductor ( a heat pipe or thermal plate comes close), there will always be a temperature difference between the heat source and the print surface. The PE

Re: Water Measureing Sensor - 6 months ago

We need more information. What are you trying to measure? Water temperature, water quantity, water quality, water pressure, water pH...? Assuming it's water temperature, given your thermistor attempt?

Re: thermistor calibration - 6 months ago

QuoteVDX ... you can try with fluid metal with a low melting temp. I like . A bit expensive, but clean, transparent, good to 400C or so, and doesn't amalgamate to electrical leads like liquid metal. Also see for more than you want to know on platinum RTDs. Hope this helps.

Re: Hot/Cold swap Nozzle idea - 7 months ago

At least in the US, the patent system is totally out of control. In fact, it's so bad I have twice accomplished "reverse patent trolling". It works like this. I make a thing, and publish it for all to see and copy. A patent troll contacts me and says that I am violating their patent, and they are going to take me to court. I invite them to take me to court, and advise them that the very likely

Re: PID tuning failing for larger bed? - 11 months ago

Where did the PID coefficients come from? They look a bit...odd, shall we say. And why are you limiting the bed power to 50%? My last thought is that a bad thermal sensor, or a thermal sensor with very poor thermal coupling to the bed, or a thermal sensor with flaky or intermittent wiring could easily display those symptoms.

Re: VDE-200 (Schnekenstruder Rev. 2) - 1 year ago

Quotecyber_v1 It looks like the 1.60mm bore won't work as the knife then intersects the filament on all sides. I also don't really understand how it may work since the part is totally symmetrical and it can't "prefer" to which side to push the filament. Yes, and a nut intersects its bolt on all sides. Yet observe, grasshopper, that it goes up and down the bolt when either is rotated. Or sometim

Re: VDE-200 (Schnekenstruder Rev. 2) - 1 year ago

Quotecyber_v1 Quoterq3 Quotecyber_v1 Hi! I'm curious about this design; do you mind sharing the model or explain better about how the titanium insert was made? I don't really understand how it can have an internal bore of 1.60mm if the filament diameter is 1.75mm. The design is basically a swashplate, with the friction of the bearing balls providing the drive ratio between the inner hollow drive

Re: VDE-200 (Schnekenstruder Rev. 2) - 1 year ago

Quotecyber_v1 Hi! I'm curious about this design; do you mind sharing the model or explain better about how the titanium insert was made? I don't really understand how it can have an internal bore of 1.60mm if the filament diameter is 1.75mm. The design is basically a swashplate, with the friction of the bearing balls providing the drive ratio between the inner hollow drive shaft, and the outer b

Re: An Optical Filament Sensor That Actually Works - 1 year ago

Quotelooxonline What was the reliability like with movement detection. I notice that you are looking for even just a single value difference between the two averages. It seems like ADC noise alone may be able to generate that. I am struggling to understand how movement of the filament would produce a different value across the ADC when the filament tolerance is around 0.005mm diameter these days.

Re: Need for a Bowden extruder for a faithful servant. - 1 year ago

Mike, it's not a bowden, but this is what I've been using on my delta for several years now. Other threads in the tech forum have more details and thoughts. Rip

Re: An Optical Filament Sensor That Actually Works - 1 year ago

Quotelooxonline Did you ever have any issues with filament dust messing with the ADC readings and causing false triggers? Nope.

Re: An Optical Filament Sensor That Actually Works - 1 year ago

Quotelooxonline Am I right in thinking that you needed to cut two slots in the guide tube at the base for the LEDs to shine through? No. If you look at the printed circuit board, the filament goes through a small hole across which the LEDs shine and detect. The guide tubes just guide the filament.

Re: My custom watercooling setup - 1 year ago

Re: How variable does air cooling need to be? - 1 year ago

I use two 12 volt blowers in series on the 24 volt PWM signal. This gives me control from 5-100% PWM. Although PETG is often advertised as needing no cooling, I find that the difference between 15% and 20% cooling speed can make or break bridges. So yes, fine control is very useful, and why would you Mike, of all people, think otherwise? There should be pico-Pascal control of the air flow versu

Re: Is there any way to compensate for bed thermistor error? - 1 year ago

The only method I can think of is to modify the thermistor_11.h file in Marlin/source/module/thermistor. The last column in the file is the temperature reported for each ADC reading.

Re: A rebuildlog for a Delta printer - 1 year ago

Mike, I have used my IPhone with the "Vibration" app to get resonance readings for both the bed and effector on my delta, running Marlin with Input Shaping by Tom Brazier. It worked oddly well, although the current input shaping is NOT delta compatible, since it only deals with the X and Y axes. The take away is that the IPhone has a pretty darn good accelerometer, and the app I mention uses it p

Re: CNC vs 3D Print - 1 year ago

Quoteleadinglights A medium-scale way of doing the bearing carrier is to make up a jig that could be fitted in a lathe chuck so that each of the bearing mounting surfaces and internal threads could be cut before turning the block 120º to turn the next position. Old-fashioned (pre-CNC) machinists would make 100 of these before breakfast. Nice to see that your project is ongoing. Mike That won't

Re: CNC vs 3D Print - 1 year ago

Quotedekutree64 Initial printing tests are not looking good. Lots of underextrusion, especially at the start of each line. Retract moves were failing entirely (vibrating in place) until I lowered the max velocity to 3mm/s, and still sometimes failed to de-retract. 2mm/s doesn't visibly skip, but apparently is still missing some steps. It's also back to not following the helix after retracting, p

Re: CNC vs 3D Print - 1 year ago

Quoteyet-another-average-joe An idea about drilling the shaft... With a drill press (fixed part, spinning drill bit), the drill tends to deviate. Moreover, drill press chucks usually have a huge runout. With a lathe it's the opposite : the drill tends to auto center, even without center drilling, or with a poorly aligned tailstock. It's a fact, experienced it many times, never understood why... R

Re: CNC vs 3D Print - 1 year ago

Quotedekutree64 I see no reason to use metal at all anymore. Tom Brazier's style of carrier with integrated hollow posts is a thing of beauty. With a bit of trial and error you can get it to print out ready to use, no cleanup needed (attachment Carrier.jpg). With a belt printer you could just put a bucket at the end and print more than you could ever sell So the only difficult production steps

Re: CNC vs 3D Print - 1 year ago

QuoteVDX ... want you compare 3D-printing vs. lost cast molding from 3D-printed wax parts? Made something for one of my sisters this way - the "master" was resin-printed, then copied into wax, then LC-molded ... was around 3-5 Euros per part for 100 pieces: I've considered lost print molding, but once you're into hundreds of parts, CNC machining gets to be quite reasonable. At least for my si

CNC vs 3D Print - 1 year ago

Attached is a photo of bearing carriers for the VDE extruder, against the NEMA14 motor I am currently using.. One (on the left) is CNC machined from 7075-T6 aluminum, at $60 each in lots of five, by hubs.com. The other (on the right) was 3D printed in 316 stainless steel by JLCPCB.com, at $8 each. Shipping was $3, and much faster than expected. Both parts were fabricated from the same STEP file.

Re: Surface uneven - 2 years ago

Two thoughts come to mind: 1) The nozzle temperature is too high? I have printed some brands of ABS at 220C. 2) The filament is "wet", and needs to be dried? ABS is notorious at absorbing moisture during storage.

VDE Extruder Video - 2 years ago

Tom Brazier, a gentleman in Great Britain, has a YouTube video on his home-made version of the VDE-100 extruder. Tom has been instrumental in tremendously improving Marlin, particularly as regards fixing very old issues of ADC readings, his introduction and implementation of MPC (Model Prediction Control) for much better control of hot end temperature, and his recent work on movement shaping in

Re: prusa ir filament sensor not working on skr 2 board Marlin 2.1.1 - 2 years ago

Quotebigrip Tried a new sensor but it still doesn't work. tried the firmware from the skr2 github page, doesn't work. does anyone have an idea? Many filaments are infrared transparent, even if they look black to the human eye. Try triggering the sensor with something completely IR opaque, like aluminum foil, if only to see if the sensor is actually "working".

Bloviating on Temperature Sensors - 2 years ago

Well over a year ago I designed, fabbed, and installed a linearized amplifier based on the TI OPA388 operational amplifier for a PT1000 RTD. Attached is the reason why, which includes links to Texas Instruments' excellent design spreadsheet, and simulation software. The zipped Gerber files for the board are also attached, as is a discussion of the amplifier component values. I often get calls an

Re: Building a CoreXY : machined or printed parts ? - 2 years ago

Nice!