I'm still around, but have not been active here for quite a while. I have a working RepRap printer, and use FreeCAD, to generate STL files, Cura to make G Code, and Proterface to run the printer. I'll be glad to help. Johnby JohnDH - New Mexico, Albuquerque - RepRap User Group
I solved my adhesion problems with ABS on glass by using a stick of 'Elmer's Washable School Glue' . I make like I'm going to mount a photo on the glass by smearing a thin coat of the glue over the area to be printed, being sure about the edge areas. I do this before each print. After the print I wait until the bed is below 50C. Then I can usually just pull the part off the glass with a twist ofby JohnDH - Reprappers
A basic problem in porting Arduino 3D printer code to a processor running a Linux operating system, is how to establish a non-blocking serial communication between G code reading software and the low level code that parses the G code to drive the motors and extruder heaters. ur3dchef - can you explain how you achieved non-blocking serial communication? Johnby JohnDH - Controllers
While I'm going the Beaglebone Black route, my end objective is a stand-alone 3D Printer system. The $45 BBB with a WiFi connection, the Printer Cape, and a 4.3" TFT LCD touch display, will fit in the space of my present SmoothieBoard controller. Initially I will use the WiFi link to import G Code files, but I hope later to do the STL file to G Code conversion on board. No PC required. The two oby JohnDH - Controllers
Detailed information on the two Beaglebone Black PRU real-time processors can be found hereby JohnDH - Controllers
The Beaglebone Black at $45 has two PRU microcontrollers built-in that can be used for real-time control, and there is provision for code on the main processor to talk with the PRU processors.by JohnDH - Controllers
I use 8" square mirror from Joann's craft store in Albuquerque ($4). The mirror is about 3mm thick, and I've used my current one for 3 months without a problem. The bed heater PCB is spaced about 1/4" above my top bed plate, and the space between is packed with strips of high temperature pipe insulation from Lowes. The insulation cuts down on heat loss from the bottom of the heater PCB, and aboutby JohnDH - New Mexico, Albuquerque - RepRap User Group
been a while since I posted. Now have my Mark II machine working solidly. Spent a couple of months switching from a Sanguinololu controller to a Smoothieboard controller. Got everything working end of March, Spent most of April cleaning up the wiring and making test prints. I have put some images where you can get to them by link. The printed parts were sliced by Cura, using it's 'raft' featureby JohnDH - New Mexico, Albuquerque - RepRap User Group
I have recently discovered a good alternative to ABS Juice, that is 'Elmer's Washable School Glue' The stick form allows you to put down a nice even coating while the glass is cold. It sticks, as good as, if not better than my best ABS Juice effort. I say 'best' because most of the time the ABS Juice mix is not consistent. I add more ABS, or more acetone in a very non-scientific way. Part reby JohnDH - Printing
With a lot of help from the Smoothie software crew, and Alizier21, I am now printing up a storm with my Smoothieboard controlled printer. I had two major stumbles: 1. Homing - Solved the problem by making each homing switch two way switching between ground and V+, rather than relying on a one way switch and the pullup. 2. Bed temperature control. With a M140 S90 the bed would never quite reach thby JohnDH - New Zealand RepRap User Group
I've recently installed the lightweight version of Ubumtu called Lubuntu an an 8 year old Win XT box. I have Tera Term. Slic3r, and Pronterface, all running, but the install of Repetier Host had problems. Part of the dependencies loaded with the install was 'mono-runtime'. Now when I try to run Repetier Host, it reports a System Error with 'mono'. Any ideas on how to fix this would be welcome.by JohnDH - Reprappers
It would be interesting to do a feature comparison spreadsheet for these four boards Johnby JohnDH - New Zealand RepRap User Group
I'm a little far from you guys as I live in New Mexico USA, but when my Smoothie board arrives next Wednesday, you will seem like family! I have been following the Smoothie project for over a year. Last August I gave up waiting for one of Arthur's boards, and made one of my own. SprintBed It is basically a Sunguinololu with the Atmel ATmega644 replaced by a mbed module. The module supports theby JohnDH - New Zealand RepRap User Group
I have had great success using the 'Brim' feature of Slic3r to prevent corner curling. I was printing on an 8" square of frosted glass, but with the extra adhesion with a 'Brim' I was lifting flakes of of the glass surface when the part cooled to room temperature. I switched back to using the mirror that came free with my Bed Heater PCB but started to have the same problem. I'm now working on thby JohnDH - New Mexico, Albuquerque - RepRap User Group
I have finally found a cure for my ABS Corner Curling problem Slic3r has added a feature called 'Brim' that kills the curling problem cold. There is a good write up of this feature at Brim I have replaced my Z-axis SAE threaded shafts with metric (8-1.25mm) and these shafts, that are noticeably straighter, run much more smoother. Had problems with a Hotend bought on Ebay from Poland. There wasby JohnDH - New Mexico, Albuquerque - RepRap User Group
I also have the same problem of "Applied with small brush. the liquid still forming islands", and have been thinking back to my photo film developing days, about 'Wetting Agents'. I find that LFN is still available on Ebay at $8.95 for a ten year supply. Edwal LFN Wetting Agent is a low foam, liquid wetting agent. Just two drops of super-low-foaming, non-ionic LFN in a pint of developer I haveby JohnDH - Reprappers
Thanks Cameron, but are there other dimensions that are considered 'standard'? Is there somewhere that I can look to see what has been agreed as part of the 2012 Standard so far, and what areas are still under discussion? As a Reprap newbie, that has only been involved for 6 months, I can only say that any set of standards would be goodby JohnDH - Developers
In upgrading parts of my Prusa Mendel, I find myself struggling to establish basic dimensions like: a) Pitch between X smooth rods b) Pitch between Y smooth rods c) Extruder Mounting hole pitch d) Pitch between Z smooth rod and motor shaft. If you are going to have standard then you out to start out with a set of basic dimensions. That way if someone designs a new part, it should at least fit.by JohnDH - Developers
I found sugar (One tablespoon raw sugar per cup of water) worked good for things less that 1" high, like a Wades big gear, but on tall things (2.5") like an X assembly end, I had a problem. The center area of the base would stay stuck, but one or more corners would lift, resulting in a distorted part. I switched to ABS juice, which worked a little better but was not a complete fix for the cornerby JohnDH - Reprappers
New X Carriage installed. Going to mount indicator for 'Bed Leveling', as per nophead, before installing extruderby JohnDH - New Mexico, Albuquerque - RepRap User Group
Take a look at this X Carriage Jonas's Carriage I have made one and it is sitting on the bench waiting to be installed. looks great!by JohnDH - New Mexico, Albuquerque - RepRap User Group
Taking advice from the maker of my frame plastic, I used SAE threaded rod and 8-mm smooth rod; however in my wisdom (?) I chose to use 28TPI 5/16" threaded rod. 28TPI = 0357142" = 0.9071406-mm per turn. Taking nophead's point about using an integer number of fullsteps rather than microsteps, for 0.25-mm layer height 55 fullsteps = 0.2494635-mm. Close enough for government work. I'm using a nominby JohnDH - New Mexico, Albuquerque - RepRap User Group
I have only used ABS from the start, and I think it is harder to work with, and there are lots of little tricks to learn, like the right use of fans. I have a 75-mm 12V fan sitting 50-mm off of the bench blowing up on the electronics board. Without it the FET running the bed gets too hot and shuts down the microcontroller after about two hours. With this fan in place the electronics will run allby JohnDH - New Mexico, Albuquerque - RepRap User Group
Hi Glen, On the motor spacing. I have a 1.3mm washer between the big wheel and the body to center the bolt hobbing. But with that in place I had to space the motor back 3mm from ins mounting surface to line up the little and big gears, and this with minimum clearance between the back of the small gear and the motor body. My first print of the small gear came out with fuzzy teeth on one side. Iby JohnDH - New Mexico, Albuquerque - RepRap User Group
Update Complete 1. 27 6-32 plain nuts, and 40 M3-0.5 plain nuts replaced with nylon insert lock-nuts. - No more loose screws 2. Added 16 tie-wraps (One per bearing on outside end) - No lifting bearings 3. New bed top plate (Model Aircraft 1/8" plywood) - Clips holding glass moved away from 'All-Home' position 4. New extruder plastic "Greg's Wade Reloaded Extruder" New Extruder from LutzBot Haby JohnDH - New Mexico, Albuquerque - RepRap User Group
Hi Glen, I really like the way Jonas Kuehling's 'Gregg's Wade Reloaded' extruder is put together. (Got the first link from you), and have for the last few weeks have been trying to get my existing extruder to print the parts. The gears came out Ok but the main body always beat me. last week I gave up and ordered a kit of plastic parts from LulzBot in Colorado for $23. They and theby JohnDH - New Mexico, Albuquerque - RepRap User Group
The quality of my printed parts has been steadily going down hill over the weeks, and this is because the machine has been steadily going out of calibration due to several reasons. As an example of how bad things have gotten look at this image: Note the bearing holder lifting off the bearing on the left. The bow in the Extruder Base and the bow in the X Carriage. Also note the "leaning Tower ofby JohnDH - New Mexico, Albuquerque - RepRap User Group
Hi The electronics for Reprap is very close to what my day job used to be. (Stepmotor 3-axis motion control). So if you have some specific problems, let me know. Maybe I can help you over a hump? Johnby JohnDH - New Mexico, Albuquerque - RepRap User Group
I am proposing a new project -'Sprintbed' Sprintbed is to be a Riprap controller similar to Sanguinololu, and Ramps, but based on a mbed CPU module rather than an Arduino module. The mbed LPC1768 module uses a 100MHz 32-bit ARM Cortex-M3 CPU, and has a built in USB interface that can be used both to load firmware, and for serial communication. NXP provides free on-line tools for code developmenby JohnDH - New Mexico, Albuquerque - RepRap User Group
I use one tablespoon sugar to one cup of water. I wait until the bed is near 100C then paint the print area. Then when the bed is happy and the Extruder starts to heat I wait until it is about 200C and put on a second coat. Not sure if all this is necessary but it works. If you let the bed cool to 40C the part comes away with a little tug of the hand. Clean up is just with a wet rag. You can alsoby JohnDH - New Mexico, Albuquerque - RepRap User Group