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Everybody here is a developer. Share what you are doing !
Re: DB25 for consolidating stepper wiring - 8 years ago
Gecko G540 (integrated 4 axis drivers and a few other things) uses DB9's for each stepper. Zero issues with this setup, and I personally run much higher voltage and current through mine than anything that the current crop of printer boards do.by Koko76 - Controllers
Re: When using resistors for inductive prox sensor, do they effect range? - 8 years ago
Range is dependent on sensor design, and material being sensed (longest with steel or iron, lower with aluminum). It can be influenced by supply voltage, you are better off being on the higher side of the range. Nothing you can do with a voltage divider will boost the range of the sensor.by Koko76 - General
Re: Saving the RepRap Project - 8 years ago
Quotereifsnyderb Hello, You are making statements without having any knowledge of what machinery I have, how many hot-ends I can make in a week, how much time it takes per hot-end, etc. You have no idea if I am profitable or not profitable. Yet you make statements that sound like I have no idea what I am doing. I know how long it takes to make a J-head. I know what can be outsourced (to a USby Koko76 - General
Re: Saving the RepRap Project - 8 years ago
Quotereifsnyderb Hello, I do not need to "farm out production" as I have this machinery. Yes, this machinery does have a cost and these "mom and pops" have already purchased the machinery as have I. You completely missed my point. I have learned to manufacture. Without learning to manufacture, there is no way I would have possibly been able to make the number of J-Head hot-ends I have made.by Koko76 - General
Re: Saving the RepRap Project - 8 years ago
"Reducing the "copying" time down to around 15 minutes requires at least $30,000 worth of machinery and a considerable amount of time. (Some of this machinery is bought used to get to that price point.)" Nonsense. Farm out production to a shop that can do the work. None of the parts to anything you've shown is difficult to make for a reasonable shop. You might have a few dollars in fixtures bby Koko76 - General
Re: Duet development news - 8 years ago
Radial blowers work better for some tasks than axial style, the ones I like that have decent lifespans are only found in 5v and 12v in smaller sizes. You asked for feedback, and you have at the least 5v available on board. Not sure why a jumper to select system voltage or 5v is such a stretch.by Koko76 - Duet
Re: Minimal heated chamber - 8 years ago
For less tearing than Mylar there is reflectix (bubble wrap with aluminized outer skin). Sold at Home Depot in the US as home insulation. Cuts with scissors and has a decent r rating.by Koko76 - General
Re: Duet development news - 8 years ago
Quotedc42 - is there a particular reason why you want to use 12V fans on a 24V system, when 24V fans are readily available and inexpensive? There are already ways to run a 12V fan from a Duet with 24V power, if you add an external 12V regulator. Yes, because although you can find some fans that are 24v there is a MUCH greater selection at 5v or 12v, particularly the smaller type that would benefby Koko76 - Duet
Re: Boro glass question. - 8 years ago
Quotestephenrc The glass may have had some stress left in it from the manufacturing process and the heating it up for printing helped relieve it with the end result of it having a bump in the middle. The temp where that happens is somewhere around 1050 farenheit. Unlikely.by Koko76 - General
Re: Saving the RepRap Project - 8 years ago
You know how to fight all of that? Learn. Go out and learn. While there are individual part examples that can only be made on a 3D printer man got along fine for some time without them. Go out and learn to make things, with a mill, a lathe, a file or a pencil. Relying on one technology (3D printers) to save the world is foolish. And it takes no less know how or skill to make a part on a 3D priby Koko76 - General
Re: Boro glass question. - 8 years ago
QuoteDark Alchemist So, anyone hear of glass permanently deforming like that over time? No, because it didn't. Chances are that it was manufactured that way.by Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one
- 8 years ago
Quotejonnycowboy Quoteto3dornottobe About splitting the encoder from the motor; You can't compensate structural misses (play, backlash) with PID tuning. You need an intelligence that's capable of determining the difference between the input and the output. and store these differences to make it 'as close as possible' (stil, not ideal).. But this would require both an encoded motor and an encodedby Koko76 - General
Re: 0.0mm or 0.1mm - 8 years ago
QuoteWZ9V All of the calibration guides I've seen suggest using a piece of paper (0.1mm) as a feeler gauge. This would mean that when you issue X0 Y0 Z0 it will actually be X0 Y0 Z0.1 should I be subtracting out that 0.1mm so that the hotend is actually at Z=0? Seems to me that if I don't the Slicer will make a 0.2mm layer 1 at 0.3mm in height. You are correct. I use a piece of stock that isby Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
Quotejonnycowboy Thanks for your reply Koko. What this solution "solves" is the magical 100g flying hot end which will never be acheivable with a stepper based solution. But yes a stepper will be easier to integrate. Servos are not that difficult to control - a good PID and high resolution/accuracy and you're 90% of the way there. The rest is software tuning. You don't just go out and get "aby Koko76 - General
Re: bed level sensor trouble - 8 years ago
QuoteDjDemonD Okay I take your point that perhaps I'm getting too worked up about this. But I know I am not the only person baffled by these sensors. But can anyone suggest, as this will help me to understand these things, why the second sensor mentioned Npn NO ljc18a3-h-z/bx would give 10.13v presumably connecting signal to the input voltage when the sensor is open when it is meant to be NPN aby Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
Quotejonnycowboy QuoteKoko76 Good luck Paul, I believe that you will find "closing the loop" to be more difficult than you think. Modern machine tools still keep servo encoders on the motor shaft instead of the moving table for very good reason, the same one which makes it difficult to close the loop here. Personally I think this is a dead end and I am working to make a lightweight direct solutby Koko76 - General
Re: bed level sensor trouble - 8 years ago
QuoteDjDemonD Yes that's a very practical way to do it, and would allow NC or NO operation independent of the sensor switching mode. Does the delay in the relay switching cause issues with homing successfully if the homing feedrate is too high? That's dependent on sensor frequency and desired resolution. Delay is trivial to account for as long as it's consistent. Homing feed rate should not beby Koko76 - General
Re: bed level sensor trouble - 8 years ago
If a voltage divider is too complex, use the sensor (at rated voltage) to switch a relay. It works, is very simple and will interface easily to things that need a switch input.by Koko76 - General
Re: bed level sensor trouble - 8 years ago
What I meant was that you decrease accuracy and sensing distance by lowering the voltage. Something that can be determined by reading relevant material instead of trying by trial and error. If the parts don't match the data sheet perhaps you might question your source and why you can get something so cheap when most places don't have it that cheap. I deal with prox sensors in large machine tooby Koko76 - General
Re: bed level sensor trouble - 8 years ago
Inductive sensors derate when used with aluminum as opposed to steel. Every one is different, but it can typically be 40-50% of the distance that steel (in this case it's actually rated with a particular iron material) will be. It gets worse too, as you use longer range sensors, your accuracy goes down. Generally with these sensors it's around 10% of the full detection distance, therefore withby Koko76 - General
Re: Servo motor driver Polulu drop-in replacement - 8 years ago
Quotejonnycowboy What about instead of Polulu replacements you use something like Dynamixel AX-12 or MX-12 servos? Then you save the 20$ controller (though the motor itself is more expensive). You also gain temperature and load feedback. Resolution can be pretty good depending on if you use the AX-12A (slow but accurate) or AX-12W or MX-12W (faster but less accurate). Only the MX of those listby Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
Good luck Paul, I believe that you will find "closing the loop" to be more difficult than you think. Modern machine tools still keep servo encoders on the motor shaft instead of the moving table for very good reason, the same one which makes it difficult to close the loop here. Personally I think this is a dead end and I am working to make a lightweight direct solution. I think I can get prettby Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
So what do you intend to do with the sensed position of the filament with this wheel? Is your intention to modulate the XY feed to keep up with the extruder? Or are you intending to modify the feed at the other end of the Bowden based on data from this encoder? Both of those have drawbacks, some significant. History in this project used a DC motor with encoder for filament extrusion. Nobodyby Koko76 - General
Re: Help adjusting the microstepping settings - 8 years ago
It can be if the jumpered pins on the motherboard are shorted via traces on the board, as some of them have been known to be. Might be worth a check with a multimeter.by Koko76 - General
Re: Ideas for 1000mm^2 bed - 8 years ago
Quotegmh39 Correct me if I'm wrong, but my gut tells me you could mill/drill holes throughout the plate to help counter the thermal expansion. You would need to do some thermal analysis to keep the holes as small as possible and figure out the best pattern, but it would give the the aluminum some "room to grow". Not going to help that issue. Pocketing the plate will cause more issue than help, eby Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
30g for 750mm in case anyone wanted to know.by Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
QuoteMutley3D QuoteKoko76 QuoteMutley3D Flex shaft weight is negligable since it is quite literally suspended/floating due to the arc taken by the ptfe tube within which it is housed. inspiring/illuminating....slip of the toungue But what is the number? If you don't want to share that's one thing, but I'm capable of determining what is "negligible" all by my self. LOL when i say negligible Iby Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
QuoteMutley3D Flex shaft weight is negligable since it is quite literally suspended/floating due to the arc taken by the ptfe tube within which it is housed. inspiring/illuminating....slip of the toungue But what is the number? If you don't want to share that's one thing, but I'm capable of determining what is "negligible" all by my self.by Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
There are several alternate ways to increase the ammount of filaments extruded which don't mean mounting more extruder motors to the moving portion of the head. Perhaps some "out of the box thinking" can be applied. After I get the weight down on the single extruder I'll tackle some of these.by Koko76 - General
Re: This engineer claims 100 grams direct extruder. I want one - 8 years ago
What is the weight of your flex shaft itself?by Koko76 - General