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Re: ESP8266 on Prusa i3? - 9 years ago

Maybe the latency problem could be mitigated by increasing the size of the move buffer in the firmware?

by Ezrec - Developers

Re: Converting the existing firmware to work for the powder printing process - 9 years ago

Glad to see I'm not the only one! I have finished the software (host and printer side) for my powderbed printer: BrundleFab It uses a (very slightly) modified GCode, and is easily driven by Pronterface or other G-Code senders. The software is in three parts: Software - Host-side software for converting from STL to GCode (with an intermediate SVG slicing step, like UV resin printers) Firmware

by Ezrec - Powder Printing and Selective Laser Sintering

Re: Xssink Boxd 3d printers - Good or Bad reviews anyone? - 9 years ago

Yes, the 'we only have a CAD picture and a grainy YouTube Video of someone trying to put together the frame" level of professionalism was why I held off my purchase. Things I'd expect to see on the Xssink/DIYTechshop page that would make me a bit more comfortable to buy from them: * Full parts list of what is in the shipped kit (especially the 'upgrade your i3' kit) * Video of an assembled devi

by Ezrec - General

Re: What do you think is the next great push in the RepRap Community - 9 years ago

An easy to use, low material cost powerbed printer, that is capable of printing full-color parts as strong as current FDM parts. That's the tack HP is following with their current powerbed design, and I wish them the best of luck. With a cheap, strong powder bed system, you greatly expand the library of printable parts - no support framework needed for your parts.

by Ezrec - General

Re: Xssink Boxd 3d printers - Good or Bad reviews anyone? - 9 years ago

I am also waiting for someone to report a review. Or even some pictures of calibration objects.

by Ezrec - General

Re: Servo motors on Prusa i3 - 9 years ago

misan: Thank for the PDM Corp URL - very good information! /me bookmarks...

by Ezrec - Stepper Motors, Servo Motors, DC Motors

Re: 12 x 12 x 12 printer 25% off first 20 Grand opening sale! - 9 years ago

QuoteRogue45 Just bought your 8i kit. Excited and will be posting a review! Hoping for a great experience! I'm also interested in the 8i - I'll be awaiting your review!

by Ezrec - For Sale

Re: Servo motors on Prusa i3 - 9 years ago

I'm working on a similar project - I'm working on using a Adafruit Trinket Pro (ATmega323) for my ink sprayer control for my powder bed - Y axis is a DC motor + encoder (600 DPI) with a InkShield. The DC motor is velocity, not position, controlled which makes it simpler to manage - I just bump up the PWM if going too slow, bump down if going too fast. For accurate fast positioning, you will nee

by Ezrec - Stepper Motors, Servo Motors, DC Motors

Re: Open Source DC or BLDC controller - 9 years ago

I'm using a stack of Arduino shields DC motor control, firmware at https://github.com/ezrec/BrundleFab-firmware It is very big and bloaty, and the DC motor control is very experimental, but the Axis_DCMotor.h class contains all the magic. I'm working on velocity control at the moment (for accurate multi-axis movements), but it's still a work in progress. I'm using the Adafruit MotorShield V1 o

by Ezrec - Stepper Motors, Servo Motors, DC Motors

Re: TFT GCode visualization - 9 years ago

For a point of reference, an unoptimized sketch with just the visualization support (null axes, no SD card) clocks in at approx 28K flash, 3K ram. I should be able to squeeze that onto a Atmega328P device (Arduino UNO), and hang it off the TFT as a GCode pass-through device. If I get that working, would anyone be interested in something like that as a Rep-Rap add-on? (You'd plug it between yo

by Ezrec - Developers

Re: Stepper motor alternative ? - 9 years ago

Quote691175002 [What measurable advantages does a DIY servo have over a stepper motor? All I'm seeing is additional cost and complexity. Advantages (for me) are one and one only - exploring DC + Encoder motor control with parts I have laying around. I only had two steppers on hand (for my Z and E powder axes) , so I cobbled something together from what was in my parts bin. Although it is fun

by Ezrec - Developers

Re: 320X240 LCD on Ramps 1.4 - 9 years ago

Yes, but it prints too - I'm using DC motors + encoders for my X and Y axes, and pretty much had to roll my own firmware. I had this TFT laying around and the code space on my Mega, and a few hours...

by Ezrec - RAMPS Electronics

Re: 320X240 LCD on Ramps 1.4 - 9 years ago

This Adafruit 2.8" model uses the same driver chip. You should be able to easily use their Adafruit_GFX library to talk it, regardless of the pins on the RAMPS you connect to. If you have any interest in adding a UI to your system, let me know, I'm working on a visualization system for a similar TFT model (Adafruit 1.8") for BrundleFab

by Ezrec - RAMPS Electronics

Re: Stepper motor alternative ? - 9 years ago

QuoteMachineHum Quote691175002Gearboxes introduce a disgusting amount of backlash until you start paying 200$+. Truth... Yes, and optical encoders and a good control system takes all that backlash out. I have a gear motor with a rubber grommet driving a fishing line belt system, and I get 250 micro resolution on that axis without even trying hard - it's all about the encoder when working with

by Ezrec - Developers

InkShield Improvements - 9 years ago

I recently blew the MC34063A on my InkShield, but I had some MC34063Es laying around. Unfortunately, they ran hot enough to cook and egg, and would burn out within a few minutes. After close inspection of the InkShield schematic and the datasheet, I found that I could reduce the current draw, but keep the same output voltage by reducing the output current by a factor of about 10 (from ~400ma to

by Ezrec - Powder Printing and Selective Laser Sintering

Re: Stepper motor alternative ? - 9 years ago

I would invite anyone interested to take a look at my firmware for my powder bed printer. I am using a mix of DC+Encoder (X and Y axes) and stepper motors (Powder(E) and Part(Z) axes) in my firmware. Very C++ish, I know, and I need to add 2D kinematics (currently it's only an axis at a time, which isn't an issue with powderbed), but it should be a start. I use a very non-PID system (ramp up, t

by Ezrec - Developers

Re: Plastic Droplet Generation via Piezo - 9 years ago

Ok, understood. Alternate concept: use SLA resin as the binder for powder bed, and cure with UV light. The SLA resin has a very low visocity (lower then wax, IIRC) and should be able to be ejected via a piezo (maybe even thermal) printhead. The trick will be make sure the actual printhead is well shielded during the UV curing pass, but colorants should be able to be added to the SLA resin for

by Ezrec - Plastic Extruder Working Group

Re: TFT GCode visualization - 9 years ago

Ah, M105 only. Now it all makes sense.

by Ezrec - Developers

Plastic Droplet Generation via Piezo - 9 years ago

I came across this successful DIY printhead experiments documented on the wiki (http://reprap.org/wiki/Scratchbuilt_Piezo_Printhead), and I was wondering if anyone (in any industry) has successfully used piezo printhead to generate plastic droplets? I know that Tektronix/Xerox's Phaser wax printers used a 'hot' piezo printhead to eject wax (I have one of them sitting around at home gathering dus

by Ezrec - Plastic Extruder Working Group

Re: TFT GCode visualization - 9 years ago

For your panel, what printer firmware is it expecting to talk to? The firmware for your panel seems to assume a JSON reply format (which I would like to use in my powder bed printer), but I don't see that documented anywhere.

by Ezrec - Developers

Re: axes move only one direction in hbot config - 9 years ago

For H-BOT, you need to reference the H-BOT equations: dX = ( dA + dB )/2 dY = ( dA - dB )/2 So if you want to 'swap X and Y axes', you need to reverse the DIR of only *one* stepper. Reversing both steppers will, as you found out, just reverse the direction of the existing axes. Edit: Remove emoticons.

by Ezrec - Developers

Re: axes move only one direction in hbot config - 9 years ago

* Verify that the DIR line to the stepper controllers is actually toggling when you change direction (config issue, usually) * Verify that you have not cross-wired the stepper: ABCD. not ABDC or BACD, otherwise you can get odd results. * Did you do a clean build of Marlin after the config changes? (no .o files anywhere before the build!)

by Ezrec - Developers

Re: TFT GCode visualization - 9 years ago

I'll do an analysis in a bit (I have a STM32 I can try it on) but off the cuff that should be much more than enough code/data space.

by Ezrec - Developers

TFT GCode visualization - 9 years ago

For my powder bed printer, I find it useful to have an on-board visualization system of the model that has been rendered under the powder. I think this might be generally useful. I used the Adafruit ST7735 for my project, but the codebase should be readily adaptable to any full color TFT. Time lapse video of the visualization system running: And before you ask, yes, that is a 3D projection w

by Ezrec - Developers

Re: Centrifugal laser sintering - 9 years ago

Ok, interesting idea. Here's how I would rough & ready prototype it for liquid SLA: * Materials: ** Vertcal centrifuge (1m diameter so we don't have to go so fast) with water-tight sides *** The sides should be high enough to contain all the SLA fluid for a full build when the centrifuge is stopped (to prevent spills on a power outage) ** Hall sensor + magent on centrifuge or optical encode

by Ezrec - Powder Printing and Selective Laser Sintering

Re: Reprapper's new filament - Copper PLA - 9 years ago

Out of curiosity, is this electrically conductive in any fashion? If so, what is the resistance per mm or cm of the 1.75mm filament?

by Ezrec - For Sale

Re: Generating color BMP slices out or STL or ABM - 9 years ago

I use 'repsnapper' to output a directory of individual .svg files (one per layer), then use this shell script to convert to PNG: #!/bin/sh SVG_DIR="$1" for d in `ls ${SVG_DIR}/*.svg | sort`; do convert -border 10 $d `basename $d .svg`.png done

by Ezrec - General

Re: Feedback Wanted on Working SLS/SLM 3D Printer - 9 years ago

Suggestion: Get a fuser unit from an old laser printer, affix it to the leading edge of the powder wiper, and run the fuser unit as you do the powder wipe. If you get the fuser temp correct, that should 'relax' the rasterized nylon enough so that the edjest curl down before the powder is applied.

by Ezrec - Powder Printing and Selective Laser Sintering

Re: Microwave sintering - 9 years ago

SIS - that's the same as the announced HP powder bed printer that uses the ink bar and thermal fuser, right? I'm working in a similar vein, but on a sugar powder bed that uses sugar and binder, and will use a halogen lamp to fuse/dry each layer after printing. I'm working on a design where the part z layer has multiple powder passes, since the binder shrinks the powder thickness when applied and

by Ezrec - MetalicaRap

Re: Stepper motor alternative ? - 9 years ago

I'm using DC + Encoder on my powder bed printer - DC + Encoder is pretty sweet for constant velocity (the printhead axis) systems. My Y axis is a geared DC + Encoder (hacked up ball mouse optics on the fishing line drive) and is slow enough that inertial overshoot isn't a big issue.

by Ezrec - Developers