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Re: New to Duet, coming from Ramps/Marlin - 8 years ago
I can't answer everything, but the Duet is configured differently than Ramps or similar. The Duet uses a config file stored on it's SD card. You can edit this file with any standard text editor. It is done entirely through the use of G codes, in your example accelerations would be set by placing M201 X1000. Y1000. Z1000. or similar in the config file. These commands can also be sent at any tby Koko76 - Duet
Re: Pancake stepper extruder - 8 years ago
Quotedc42 QuoteKoko76 Ok, so I have approximately 600 steps per mm, 16 micro steps. That's 37.5x6Ncm or 225 by your formula. I have done many 10+ hour prints with abs and pla of a variety of manufacturers/temps etc. I would characterize it as reliable. I'm trying to understand why you need or want more than 2 times that number. Maybe it's because I run a delta that does PLA infill at 100mm/sby Koko76 - General
Re: E3D V6 Nozzles are completely different from technical drawing - 8 years ago
Quotethe_digital_dentist It's nice to look at the physics but without a deeper understanding of high temperature/pressure viscous fluid flow, and in the complete absence of data, a guess is just a guess. Which brings me back to the first question: what constitutes a back pressure problem? How do you distinguish it from a too low temperature problem? Or a too low extruder push problem? Or a fiby Koko76 - General
Re: Pancake stepper extruder - 8 years ago
Ok, so I have approximately 600 steps per mm, 16 micro steps. That's 37.5x6Ncm or 225 by your formula. I have done many 10+ hour prints with abs and pla of a variety of manufacturers/temps etc. I would characterize it as reliable. I'm trying to understand why you need or want more than 2 times that number.by Koko76 - General
Re: Pancake stepper extruder - 8 years ago
Quoteo_lampe @Koko76 6Ncm x 5 x 200steps/mm=600 so it fits Daves rule of thumb?! Yes, but 20 Ncmx3 is 60Ncm and he is saying he needs that, which is double he number in the rule of thumb. My question is why if he rule of thumb is half of what he said is required.by Koko76 - General
Re: Duet development news - 8 years ago
QuoteMasterjuggler Could you clarify what the difference is between 24v and general power? Unless you are saying you have two PSUs in there, one 12v and one 24v for whatever reason... And to be clear, the e-stop is a momentary switch wired in series with the general rocker switch, to momentarily cut the power when pressed? That actually seems like a pretty good system, but I agree with the stranby Koko76 - Duet
Re: Pancake stepper extruder - 8 years ago
Quotedc42 In my experience, you need about 3:1 gearing to get enough extrusion force using a 20Ncm motor and a RepRapPro hobbed insert; or to put it another way, with a standard 1.8deg motor the product of full steps/mm and torque in Ncm should be more than 500. From this you can work out what gearing you need for less powerful motors. The OMC Stepperonline motor I linked above has 6Ncm of torqueby Koko76 - General
Re: Pancake stepper extruder - 8 years ago
Is the 70g nema17. They have a 14 pancake as well. There is also a thicker 17 pancake there.by Koko76 - General
Re: Rugged CoreXY - 8 years ago
I'm not touchy or annoyed. It's your money, your design, your printer. You asked for help and input, you keep applying value judgements like "better" without being able to quantify them. I've made a couple suggestions to help you be able to better qualify and quantify "better" for yourself. It does not appear to me from your replies that you understand what I'm saying. Perhaps it is a continby Koko76 - CoreXY Machines
Re: Rugged CoreXY - 8 years ago
I guess I thought when you said "I'm well aware of moment loads" earlier in the thread that you were familiar with them. It's not "x amount of kilos", it's force at a distance, in SI expressed as newton meter (Nm). You have static moment loads when a torque is exerted in on an axis such as mounting the rail to a vertical surface and hanging the carriage off of that, in that case the force is grby Koko76 - CoreXY Machines
Re: Do you guys know what kind of slot extrusion is this? - 8 years ago
Extrusion dies are cheap (relatively speaking). Lots of folks in industry get custom extrusion dies with a purchase of some min quantity of weight of parts. I imagine in China it's even cheaper, especially when the extrusion house has downtime. Point is that it's entirely likely that you'll never chase down anything on it. Could have been a one off run.by Koko76 - General
Re: Pancake stepper extruder - 8 years ago
I have found their website is wrong about a lot of things, the motor/gearbox I listed weighs almost double the listing (close to 200g). All up my motor/gearbox extruder block (this serves as frame for all that stuff, tension mechanism, and water cooler for the hot end) as well as the heater block itself is right around 300g. That was for a quick test of some concepts, so I didn't look to shaveby Koko76 - General
Re: Duet development news - 8 years ago
Nice! Can't wait to see these come out. I figure I'll have the new machine ready in just the right amount of time to get one of these in there. Still super curious to see what drivers you are using. I've got externals for X and Y anyway but I'm interested to see what I can expect for Z and the extruder.by Koko76 - Duet
Re: Pancake stepper extruder - 8 years ago
QuoteOrigamib What's the smallest motor possible for an extruder? Looking at the E3D titan, some people are claiming 18Ncm nema 17 motors, which weigh around 140g. Would this provide enough push on a 1.75mm filament? I'm dubious that this will do it, but my only experience is with my direct drive extruder, running a pretty beefy 59ncm motor. I'm pretty sure this is too much, but I've not had anby Koko76 - General
Re: Rugged CoreXY - 8 years ago
Quotehobbymods QuoteJamesK QuoteThe point Koko is making I feel is that our pissy little extruders weigh and exert forces MILES under the extremes these precision rails are made to take continuously Yes, looks like you are right. A quick back of the envelope calculation suggests that the static rated moment specs for mgn 15 in all 3 axis are ~2 orders of magnitude over anything the print-head isby Koko76 - CoreXY Machines
Re: Rugged CoreXY - 8 years ago
QuoteJamesK I always find it difficult to think in terms of single linear rails. Even if the turning moments are well within spec it feels more natural to design so that as much of the force as possible falls on the primary load bearing axis. Typically that would allow sizing for much smaller rails as the primary axis will typically take a load orders of magnitude above the torque load, but thingby Koko76 - CoreXY Machines
Re: Rugged CoreXY - 8 years ago
Quotehobbymods Well I'm already printing a housing to run 2, but I will take your advice and also make a single rail version. It certainly would make life easier. I take it you're a machinist/toolmaker of some sort? What I don't want to use is the MG rails, as they only have one bearing race as opposed to the EG series which has 2, and can be supplied with a grease nipple (I build everythingby Koko76 - CoreXY Machines
Re: Rugged CoreXY - 8 years ago
Quotehobbymods QuoteKoko76 Quotehobbymods QuoteLarsK @ Ikcl - I like your focus on reducing the length from center of X rods to edge of out nozzle. I have never understood that it was not given more attention. Mine is 33mm from center of rods to nozzle edge, I wish it was less, but it is hard to design something printable and something that won't melt and then I wanted the dual nozzles... But sby Koko76 - CoreXY Machines
Re: Rugged CoreXY - 8 years ago
Quotehobbymods QuoteLarsK @ Ikcl - I like your focus on reducing the length from center of X rods to edge of out nozzle. I have never understood that it was not given more attention. Mine is 33mm from center of rods to nozzle edge, I wish it was less, but it is hard to design something printable and something that won't melt and then I wanted the dual nozzles... But sometimes I see some designsby Koko76 - CoreXY Machines
Re: PTFE tube popping out of e3d v6 hotend - 8 years ago
There is a printable clip (several variations) that go between the locking ring and the brass portion of the fitting. After the tube is installed you push this clip in, and it take the slack out of the retention ring so it cannot move relative to the brass part. Without it the tube will move up and down, slowly wearing a larger groove into it with the gripping fingers of the fitting. Some diggiby Koko76 - General
Re: New delta drive - 8 years ago
Quotedc42 27:1 gearing is very high. What retraction speed and acceleration are you able to achieve? Although I guess that with a short Bowden tube on a flying extruder, fast retraction is less important. I have both the 5:1 version of that motor and the 27:1. Either fit my extruder which is direct. I did not find the 27:1 to be any improvement, if anything it was slightly worse.by Koko76 - Delta Machines
Re: Rugged CoreXY - 8 years ago
QuoteJamesK QuoteI can see a second scrap of perspex I've got there being in mortal danger of being drawn on and cut up. I really like the way you prototype your ideas. I'm trying to get more familiar with CAD, but I always quickly run up to the point where I want to hold it and see how it feels for real. There's some great creative energy running through this thread, and around coreXY in genby Koko76 - CoreXY Machines
Re: Duet initializations issues - 8 years ago
Check your endstop wiring very carefully. Make sure that positive and negative go where they are supposed to. Shorting ground and 3.3v could cause board lockups or worse. Don't worry about your Z probe to start, disconnect that and get the others working. When trying to troubleshoot a problem start with the lowest complexity and work upward. Unplug all your endstops from the board and do anby Koko76 - Delta Machines
Re: Bonding GT2 belts - 8 years ago
Check Loctite's website. They have several CA formulas optimized specifically for rubber, higher peel strength and higher flexibility. They work OK.by Koko76 - General
Re: Duet initializations issues - 8 years ago
Per the comments in that file adjust your value so the resistor for thermistor reading is 4.7k. That should help your temp issue #2. In the line with m305by Koko76 - Delta Machines
Re: High speed delta's are often not that speedy at all - 8 years ago
Quoteevandene 4000 mm/sec. sec acceleration for a NEMA17 with a Pull-out Torque of 0.42NM motor is simple not possible for a belt driven system with carriages, arms, effector and friction. Typical "bigger is better talk". Pull-out torque The stepper motor pull-out torque is measured by accelerating the motor to the desired speed and then increasing the torque loading until the motor stalls or miby Koko76 - Delta Machines
Re: E3D V6 Nozzles are completely different from technical drawing - 8 years ago
QuoteElmoC They could also get the same two step bore with a special bit that has a cutter with both the A and D dimensions. Might be costly to get made, but could pay for itself in reduced labor. Custom cutters get made all the time, we get them from time to time at work. Cost is not that much more than standard cutters, especially if you buy a few.by Koko76 - General
Re: High speed delta's are often not that speedy at all - 8 years ago
Nema17's no gear reduction, easily hits 2000, works ok at 4000. No stalling. I also run a direct drive extruder. Not sure what your issue is, but your conclusions are not universal.by Koko76 - Delta Machines
Re: Why does this design of pulley used less in Corexy - 8 years ago
QuotefilipeCampos PS: you must have 2 belts, all 4 belt end´s must be secured in the carriage. From the image it appears you have only one big belt, and i assumed is a error when you have made the image. If is not a error, them it will simply not work. No, 2 belts are not needed in an H bot design. One big belt is exactly how it works, and there is not an error in the image.by Koko76 - CoreXY Machines
Re: Full graphics smart controller dim when not connected to USB - 8 years ago
Onboard voltage reg can't keep up. When USB is connected, 5v supplied through USB.by Koko76 - General