I test printed a 16 tooth XML pulley with a pitch diameter of 10.3mm, and a 5mm hole. See attached. This part is a bit too small for my printer. I think a far smaller diameter nozzle is required, but I doubt that it would ever compete with an aluminum pulley.by dean448 - General
Gearotic Motion had detailed designs of T2.5 for 3D printers. Why don't you print them?by dean448 - General
I'm running PLA and when I tried to run home made nozzles it had a tendency to curl up. In the end I believe that its due to a poorly built nozzle that probably has some internal restriction. The factory built nozzle flows great and doen't have a chance to curl up.by dean448 - Reprappers
I have the same board. It connects up on port 5. if I happen to touch any other port and try to connect it won't simply reconnect on port 5. I have to unplug the usb cable, close Repsnapper plug the cable back in, turn repsnapper back on and connect using port5. There were some earlier posts on this with no real answer but the cause is something having to do with the USB driver. I got uby dean448 - RAMPS Electronics
How about a test on something more interesting that a cube? Cable Chain by RotoScan Specifically the Cablechainx4 version. This part has many features that can be measured with a calipers like length, width, thickness, a bridge, two round posts, the flange that makes up the side walls, and what makes this particulary interesting is that the four parts are printed in different orientationsby dean448 - Developers
One approach would be to print about 10 20mm test cubes. But there really should be more discussion around what to test print... Measure the height and widths in random locations. Meaning over different places on the face. Try not to bias the experiment by remembering what it was the last time. Possibly measure them as they are printed, not all at once. Calculate a mean and standard deviby dean448 - Developers
Madkite: I think everyone agrees that the concept looks great but on the claim of increased accuracy can you show any proof of that your parts are more accurate? On such claims It would be real interesting to post the STL for a test part and let anyone who want to print the part and publish dimensions. Accuracy to me is dimensions from top to bottom, squarness, ID, ect. Could be somethby dean448 - Developers
If Design News is considered media hype, this is the kind of hype I can agree with. Design News Start Early 3D printers were highly complex and very expensive, targeting only the largest manufacturers that could afford their several hundred thousand dollar price tags. Not anymore. ............ A recent wave of home printers and service bureaus are opening up the technology to "makers" andby dean448 - General
I don't pay any attention to the self replicating hype. Just one persons opinion, and here is why... I visited a Thermwood rounter facility 15 years back. This company makes industrial routers in the 50K to 150K range. When turing the facility I saw many instances where they were using their designed and built machines, to build the next generation of machines. I also worked in the machineby dean448 - General
I don't believe its possible to compare a cnc milling machine to reprap in the first place. Milling machines are industrial metal cutting machine used by machine shops and fabrication departments in large companies. In order to cut metal they are need to have spindle stiffness up to a million lbs per inch. Milling machines are not for the home, admitting that there are folks who managed to fby dean448 - General
Noobman, thats a great idea to unlock the Z stepper while in Skirt. None of my axis are free during any phase of printing... Do you know how to set that up in the firmware?by dean448 - Developers
FYI. Attached is screen grab of the format used to send temperature readings to repsnapper and that is displayed prefectly in the Current Temp window. Controller sends out a M105 and the board responds with a T:86.00 with parameter 86.00. I hope this helps.by dean448 - General Mendel Topics
You may want to find a way to measure temperature independent to the harware and software. Determine if it is stable or not. If stable and you just aren't getting the readings to show up in Repsnapper, its probably a firmware issue not transmitting temperature back to the board in the format Repsnapper wants to see. I tried but gave up on Gen3 because it either didn't have the power to keep uby dean448 - General Mendel Topics
I could see where a finer pitched hobbed bolt would cause problems. More teeth results in less bite per tooth for a given pressure. Less teeth results in more bite and more gap between the points for the material to not build. I'm not running a wade's style extruder with the bearing, plate and four springs. My design has no springs and is probably running at a much higher pressure. So I agrby dean448 - Reprappers
I used a drill press with an X-Y table used to carefully feed the 3mm tap into the bolt. So you are correct in that it requires some equipment. I would expect poor result if you tried this with a hand drill. I broke the tap and had to chuck it up on the threads, so it is a bit tricky. In the end I wouldn't expect needing to ever replace a hobbed bolt. You may want to try buying one off onby dean448 - Reprappers
Yes, Much deeper, see attached. Also pressure on the filiment is good. I haven't see issues with too much pressure.by dean448 - Reprappers
Since we seem to be talking about other approaches... I do notice some slight vibration in my frame probably due to motor commutation, I'm guessing. a vibration could become a flex if it hits the right harmonics. One concept to consider is to put a small antenna that could absorb/counter the vibration. It has to be farly flexible.by dean448 - General Mendel Topics
I have fans on both sides which are directed just about where the frame is. I don't think this is critical. The whole hot end is insulated. I have a non contact thermometer and measured 36 at the top of the tube when the hot ends is running at 170. The reason I could take these photos is because I had something let go in a previous design. Its amazing that you can get a decent quality priby dean448 - General Mendel Topics
I've been trying print v groove bearings to guild along a 12mm shaft. See attached. The bearing is a 608 skate bearing. I just mocked up a steel plate to mount the four bearings on for testing purposes. The issue is that I can't get the outer surface of the V to run exactly true with the bearing. The as printed part tends to grab as it rolls. I eventually turned the outer V's on a wooby dean448 - Mechanics
Heres the lower end of my extruder using makerbot nozzle, stainless tube and red PTFE liner. The frame has a trough hole in it just larger then the 3/8-24 threads of the nozzle, It threads into a 3/8-24 nut that has a washer welded to an undercut on the opposite face. Screw the nozzle into the nut, through the frame, and it locks the ceramic resistors. The stainless tube is threaded on one enby dean448 - General Mendel Topics
I need to do some work to my extruder lower end over the week end, so I'll try to take a photo then. I started out with gen 3 but couldn't get to work very well so I moved on to Ramps. I actually wouldn't bother with controlling the 12V fan and just wire it thru a switch to the PS. I'ts not a big deal to just turn it on and off as needed at this point. I guess you could leave it on all thby dean448 - General Mendel Topics
I'm running the exact same makerbot lower components on 3mm PLA at 170 without few problems. Instead of a plate I have a frame that houses a pair of ceramic resistors. Tip screws into the frame and the steel tube screws down on to the back side of the tip. The PTFE is totally trapped where only a small ridge remains where the tube tends to swell into I found that the PTFE can't back out of tby dean448 - General Mendel Topics
I understand the feet.. but don't get the need for the frame brace. Is the flex coming from the printed corners? Very high print speeds? Can't be the threaded rods...by dean448 - General Mendel Topics
I run PLA at 170 without a headed bed. Prints fine on foam core board. When the configuration is small, where the head tracks over the same surface frequenty, I need to run a fan or the part gets distorted. To an early post you really don't know the actual temperature but I can't imaging running that high temperature without part distortion. Especially when heat is coming up from the bed.by dean448 - General
Up to version 6.1 that runs on 64 bit windows. I found it to be farily useful but different enough to take time to learn. I have Turbocad and find the 3D to be impossible to manipulate no matter how long I try... maybe improved in later versions for $. I was able to import an Autodesk Inventor format from a parts website that I was able to modify in 123D then post out in STL to my printerby dean448 - 3D Design tools
Just to explain further the difference between a threaded shaft and a belt... a belt is very fast, simple but low torque. In other words you wouldn't be able to drive a CNC wood router with a belt hooked directly up to a small stepper like in the case of 3D printers. The screw can be fast but you need to go to custom designs or acme threads with multiple starts. Either way you loose speed witby dean448 - Developers
Reprap to me means completely self fabricated. Looks like I took the same route as Lantham above. I build a CNC rounter in metal. In order to build that router I had to learn to MIG weld. Both of these fabrication techniques were then appled to my repstrap. Corner pieces, servo plateforms and such were built from 3/4" 7 ply plywood (I didn't use the top grade plywood) Other connectionby dean448 - Developers
You could check that the thermistor is functioning by measuring ohms resistance across the wires. If I recall it goes from high resistance, say 50 ohms to about .5 ohms at functioning temperature. exact numbers arn't important but yes temperature.h converts ohms to deg C. Take a hair dryer and see that the number changes when it gets hot, which says that the thermistor is functioning. Whby dean448 - General Mendel Topics
This post is off the popular track so you might not get a lot of responses. Since you can work in metal, you might be interested to know that I built a 'wades' style extruder using the std wades gears but everything else is made from metal. Like skate bearings in side a 1" square tube holding the 5/16" shaft that has been hobbed and another skate bearing loaded against the filiment. All usingby dean448 - Baltimore/Wash. DC (and environs) RUG