I had the same idea. I was going to use a lego tire on a 200CPS (counts/revolution) encoder but the current arduinos do not have the ability to handle that high of a encoder reliably while printing. I was thinking of of using the STM32F4 Discovery board as my new controller but I am to busy to test anything out. The Davinci printer uses an encoder and saves the revolutions on the eeprom on theby uMinded - Developers
I have a platinum temperature sensor which is a POSITIVE temperature coefficient at zero = 1000 ohms and at 300c = 1191.5 ohms. I can not get the python script to generate a thermistor table without negative values... Anybody lend a hand? (I have no idea what the beta is)by uMinded - General
Stainless steel seems to be the choice nozzle material for all metal hot ends but it is a pain to machine. I can do brass, aluminum and steel. Which one would be the best second choice? Also because stainless has such a low heat conduction you can get away without a PTFE liner, if I change to another metal do you think I should even bother making one without a liner or am I asking for trouble?by uMinded - General
I want to make an extension for my hot end but do not know what size of drill bit to get for 1.75mm filament. I was reading THIS page and the PTFE liner they use is 3/32 and it looks like the J-Head's use a liner with 1/8" ID. What is the best size to drill through my 6mm rod so I do not need a liner??by uMinded - General
I vote for "Cost Reducing Architecture Bot" as the meaning! Question: When the nozzle is moved in the extremes of its coordinates does the end effector rotate at all? Can you use an extruder that has the tip offset from the precise center?by uMinded - Delta Machines
@nicholas.seward - Cool, thanks! Having a fully parametric and scalable version is always the hardest part of releasing a design. For light weight and cheap arms you can use carbon fiber archery arrows, their about $5 for a 30" piece. Have three in a triangle configuration and it would be quite strong.by uMinded - Delta Machines
@nicholas.seward - Have you posted the beta stl's for the Simpson yet? I really want to play around with the funky linkages! I know you running an official beta testing, but how about an unofficial for those who cant afford the $500 in one go?by uMinded - Delta Machines
The official Arduino Mega 2560 R3 uses a NCP1117ST50T3G voltage regulator specified to handle 6-20V but if you got your Arduino from a Chinese factory then definitely look up the datasheet on the specific voltage regulator. My knockoff R3 can only handle 16V maximum! The voltage regulator is circled in the pic attached. Voltage Regulatorby uMinded - RAMPS Electronics
Awesome, I replied to randomly help out and it turns out you helped me out more! lol I got THIS board from ebay to run my extra fans and things. It's pretty handy as I could not find any 5V computer case fans.by uMinded - RAMPS Electronics
Cool, I really need to add that to my Prusa i3 as my bed is always out of wack when moving it around. I was using my servo pins to control all of the cooling fans and an overhead light.by uMinded - RAMPS Electronics
I have the same board, when I used it with a mega 1280 all I did was "M43 S255 P11" to turn on the left most servo pin to maximum. The pins from left to right are D11, D6, D5, D4 Here is the board pinouts: Overview Schematicby uMinded - RAMPS Electronics
I have a ramps 1.4 board originally running with an Arduino Mega 1280 with the FTDI chip. I had fans running off the 12V rail switched off D11/6/5/4 via a simple 2N3904. I have since changed boards to an Arduino Mega 2560 R3 and now none of the PWM pins are switching. I have noticed about 0.81V differential between the 12V neg on the power supply and the 5V gnd rail on the servos header. I measuby uMinded - RAMPS Electronics
Printing problems are better suited for the general section and get faster/more responses. I had this issue with my two printers as my motors are not quite powerful enough and I had the pololu maxed out. I put the little heatsinks on them and added a computer fan and the drivers stopped overheating and skipping steps. If you feel/measure the temp of your drivers that will let you know if your rby uMinded - General Mendel Topics
Are the sources going to be released soon? I am dying to try out this design!by uMinded - Delta Machines
Oddly enough I tried printing an entire plate of Misumi T-Slot corner brackets and they printed perfectly. If I print a small object at 0.2mm it has delaminations yet a full plate is good. I guess I need to stabilize the air around the printer but for the time being I guess I will just wait until I have enough parts to print that I have a full plate.by uMinded - General
Below is the comparison, all the same settings and printed one after another. You can see that on the right hand piece there are gaps in the layers and there is even a whole layer separation in the top hole just like the print in the first post. Bigger Pic 2 things to note: 1) Don't let your cat watch the printer... Its disastrous. 2) If your ABS joice lifts off the glass you MUST replace it orby uMinded - General
I have switched to using ABS joice on my glass surface and that has solved ALL of my sticking issues. I am thinking that the part still wants to warp and after the pressure builds up over a few layers it pulls a layer apart slightly. Do you think that having the whole printer in a heated box would help out? I will post a picture comparing 0.1mm and 0.2mm prints with the same settings sides layeby uMinded - General
I am trying to fine tune my printer so that I can do unattended full plates. Currently I can print a single object such as a minifig at 0.1mm with awesome quality but for some reason the larger prints are not working very well. I have put a ducted fan that blows on the nozzle and is under gcode control. The nozzle is insulated with ceramic and has no problems keeping its temperature with a breezby uMinded - General
I have been using OpenSCAD, CoffeeScad and OpenJSCAD and each have their benefits. What do you guys think about them? Currently the most libraries are for OpenSCAD but do you think one of these contenders will take over??by uMinded - 3D Design tools
I downloaded the latest Prusa Mendel sources from github but I am in north america so I would like to convert the files into 5/16 (8.2mm) rods and everything else SAE. Is there an SAE fork or a setting buried somewhere to convert things?by uMinded - General
I found that on anything smaller than an inch squared required 85% extrusion multiplier but anything larger printed at 85% will have gaps between infill and perimeters. Large objects print great at 100% so I figure my E steps are correct and its probably a similar issue to my heat contraction.by uMinded - General
Definitely ABS, melts in acetone... kind of... It melts but does not mix into a slurry... It is from a new Canadian supplier and not being sold commercially yet so maybe the formula is a bit funky...by uMinded - General
I think I have it nailed! Bigger Picture I got that print by lowering the bed temperature to 100deg, adding a 10 loop brim, a 20 second minimum time spent on each layer, 85% extrusion multiplier, and having a fan blowing on the print the entire time. I am going to pick up a clear storage tote when they go on sale and put the whole printer inside. Have a false bottom for all the electronics anby uMinded - General
OK, some progress: Clogged nozzles suck... I have done several test prints and have found that reducing the extrusion multiplier by 15% makes the layers stay in the places their meant to be. I did not know that ABS swells so much when hot. Now I have a strange problem of things imploding somehow... That is suppose to be a 20x20x10mm calibration cube at 20% fill. You can see that the middle lby uMinded - General
I calibrated my E steps for PLA at 0.25mm layers. If the two filaments are the same relative diameter the layer thickness should not matter. Thats what I was wondering about "Packing Density" as if its like Slic3rs "Extrusion Multiplier" that makes me think that ABS changes shape when heated much more so than PLA. If my E steps will change between the two filaments then I think it might be a gooby uMinded - General
UPDATE: I have insulated under my heated bed and used RP Iron Man's tip on a piece of cardboard on top while heating and I can get to 110 bed temp in <5 min and sustain it all print now. I also rubbed a glue stick on the kapton tape and the print stuck really well. After the bed cooled to 50deg the part popped off by itself. Now I just need to get extrusion temperatures and things right. Iby uMinded - General
Thanks for the massive reply! I was planning on getting a bunch of clear storage totes this weekend any ways so I will look for a 16" cube one and that way I would have easy top access. I am printing on borosilicate glass (pyrex) and I find it does not transfer the heat nearly as well as tempered glass but it is nearly indestructible even when rapidly cooled. When you guys say 125deg and 110degby uMinded - General
yea I am having problems keeping be bed over 90deg while actually printing. I am going to put some insulation under it tomorrow and try the print again. Also will try clean my kapton off really well. I will let you know how it goes, thanks!by uMinded - General
I have a solid 8" piece of kaptop. I should have 110deg measured at the bed? I am also extruding at 220deg.by uMinded - General