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Printing issues ...
jcabrer Wrote:
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>
Thanks, but I actually want the reverse of that.
I think I am going stick with thermocouple for the extruder, and use thermistor for the heated bed which doesn't require high accuracy.
And I will be converting that manually, approximation, trail and error plus a little guessing, after all it's just one-off and the hea
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sam0737
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General
Thanks, Nice call. I found the following pull request which add delays and lengthen the pulse.
But it wasn't that.
1. Tried with 30us, doesnot work.
2. And even the DIR pin, which should flip to the other side when the motor direction is changed...isn't changing.
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Maybe I should just start going back to the old school debug method tonight: printf and trace...
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sam0737
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Firmware - mainstream and related support
I have a Arduino Mega + DIY breaking board for connecting to existing CNC steppers drivers.
I am using Reptier-host for the host.
The problem is: I can't get the motor moving. I can get motor heater and thermistor working but not motor.
I was clicking the axis nudge button on the UI (X,Y,Z as well as the extruder - with PREVENT_DANGEROUS_EXTRUDE off) - gcode is sent and ack'ed, but the motor doe
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sam0737
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Firmware - mainstream and related support
If you have got STM32 for the IO, why not use STM32 for everything that the AVR does. (Leaving the RPi does what the PC does, STM32 does including GCode parsing and downward)
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sam0737
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Controllers
(thread hijacking)
EDIT: Ok sorry maybe I wasn't following this section of forum closely...I found a few mentioned in another threads.
What is the availability of Toshiba's TB6560 in the western? There are plenty of supply in China - selling at around 3 USD each.
The footprint is not small - the chip itself is as big as the polulu shield, and requires a big resistor for current sensing. It fea
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sam0737
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Controllers
I got a thermistor with a bought extruder, but I don't have the spec for it.
So I go ahead to measure it with a thermocouple (stick them together on the heat block).
And attached is a dump of the data.
The reading is a bit noisy and fluctuating as expected, so I would like to get a averaged theoretical beta value from it and use the beta to generate the data table, instead of just copy and past
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sam0737
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General
I don't think I am following...does it work/not working on the old XP or laptop? Is your laptop's USB ok? like does it work with an USB mouse?
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sam0737
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Reprappers
Try to keep AUX-1,2,3,I2C,Servo pin compatible with RAMPS, so that existing extension will just works.
I bet that would bring you more happy customers =)
Is there a reason why not to jamming the switching power circuit to the same board? Just make the broad slight bigger?
While it looks cool, wouldn't two broads design like this makes it cost more?
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sam0737
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General
I think the putty thing you are refering is fire cement or JB-Weld, once a popular design a year or two ago, but today most modern design just goes with heater block. Because fire cement and JB-Weld are not really design for 24/7 continuous heat at 250C, they fail easily.
Have a look at this:
Manually tuning the heater and pause/resume the GCode might work, but I guess that's too much work. P
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sam0737
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Reprappers
For the source of materila, we and even commercial reprap variants are using 3mm or 1.75mm filament, usually ABS or PLA.
There is a list here you might want to check it out:
Temperature: We want to limit the hot zone as small as possible. Running too hot will resulted in a long meltzone, which will grab the wall of the extruder and get stuck. Contrary to what you think, those plastic in liquid
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sam0737
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Reprappers
Basically exactly what I am doing. I made desktop mill, could run with EMC2.
Now converting to a repstrap. Mind you, it's still in progress, I have just finished ordering everything - maybe the recipe doesn't work =)
Here is what needed.
Electronics -
1. Controllers (See wiki). I am using Arduino Mega (the RAMPS).
2. Fan out board to connect to your existing stepper driver (just DIY one,
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sam0737
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Reprappers
djamwolfe Wrote:
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> I think you just explained whats going on with my
> printer. I have a printed J-head holder and it
> must be flexing down when I am extruding. Time to
> look at and fix!!!
>
> End Thread Hijack
Sorry for yet another hijack.
Printed holder - so the holder is made of ABS/PLA and you also extrude ABS/PLA?
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sam0737
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General
And standard is only useful when something is depended on that.
Say we have being staying with 3mm or 1.75 filament so supply could be sourced, extruder could be built and improved base on that. Ditto for paper size.
We adopted GCode as the printing instruction so the electronics, program, slicer could work on the common thing, and play well with each others, and could be improved independently.
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sam0737
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Developers
One more guess: is the hot end mounted securely...and that it wasn't pushed downward by the extruder?
(I hope I am helping by throwing in ideas..)
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sam0737
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General
Right.
1. First of all you need to get a MOSFET circuit built, which is posted eariler.
http://www.thingiverse.com/thing:22202
2. Connect the VCC and GND accordingly (maybe from the input power socket), and the signal it to one of the ISP signal pins, like MOSI. Accorinding to the mapping, MOSI which is B6 is called pin 6. Then in the firmware, "#define FAN_PIN 6" somewhere in the configuratio
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sam0737
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General
You would need a MOSFET like NetPerfection mentioned.
An old school mechanical relay won't work because MCU does not have power to driver that, and it doesn't work with the PWM signal output.
A variants of MOSFET will do the job, as long as wattage/current limit are within the spec.
I don't have a sanga board, from the schematic the only spare header I spotted are the ISP pins.
Marlin support
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sam0737
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General
I don't think standardizing print size is what we are lack of.
Just like we have A4/Letter paper size for 2D printer, we actually have a very stable standard - 1.75/3mm filament that are followed by 99% of the reprap variants.
To me - output size is like font size in 2D printer analogy. Why do we need a standard to tell the end user which font size should be used for title, sub title, paragraph
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sam0737
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Developers
According to the schematic (http://reprap.org/mediawiki/images/f/f5/Sanguinololu_1.3a.png), I don't think it has a provision for fan. Look at the MOSFETs section, there are only two sets, but we need one more.
If the fan is for cooling the extruder, prehaps you could tie the Fan to the Extruder output in parallel, so whenever the Extruder is on the Fan is on. =)
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sam0737
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General
One of the popular Extruder + hot end design. With mechanical drawing and step by step machining instructions =)
For the driving part, I am only aware of those reprap form, which is obviously not optimized for machining and someone who have access to a working. workshop.
I think this one could be simple enough to be machined though:
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sam0737
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General
Does your Z axis move correctly?
Will it ever hit the heated bed?
If you repeatably run it up and down manually, does it return to the same position? (Try both fast travelling, and walk it step by step)
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sam0737
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General
A quick search on RPi forums reveals that people got SPI and I2C. ATMega supports both too.
Which is more superior than UART/Serial because clock signal are also sent along and hence could run at much higher speed. IIRC could run at ~1Mbps, compare to 115200 on UART.
And these bus support multi-slave devices too.
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sam0737
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Developers
Just to leave a note of what I have found just now.
In case ferrite core doesn't solve the problem, I would be looking for product based on ADUM4160 - a USB isolation chip made by Analog Devices.
Isolation of signals and powers (requires powers from both host/device side to power the chip and provide reference)
There are products built upon that selling at around USD 20 in China.
A cheaper alte
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sam0737
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General
I had some issues with the usb -> serial -> extruder controller. Some bytes are random corrupted every few minutes when the printer is running, I added a checksum in the protocol which help a bit, but still could cause random de-sync at random time. (with a timely hotend issue I gave eventually)
I guess ground loop and noises are the root of the problem. Just wonder if anyone has seen any
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sam0737
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General
I once managed to fry the motor driver on the V3 Extruder broad (when I used it on a gearhead DC, maybe back EMF or alike killed it).
Maybe I was just having bad luck. In general, is stepper driver stable and long-lasting? I am shipping shopping for electronics set, not sure if I should go with pololu-alike design or integrated one.
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sam0737
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Developers
Have tuning better documented: There are bunch of parameters and no idea when to tune what. It's more like black magic and try and error.
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sam0737
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General
It has been a long time since I follow the news of reprap since my repstrap extruder was destroyed. With zero power tool and all workshop refuse to drill a 0.5mm hole I just gave up. Until I found that there are some reassembled JHead+Wade's on a local bidding site, that reignites my interests. And that was when usage of heatbed was just being investigated.
What's the purpose of using spring for
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sam0737
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General
my 2 cents:
If you have heard of EMC2Linux - an OOS CNC controlling software. Basically it's very similar to what being discussed here (acceleration calculation in PC, realtime in uC). The point I am trying to make is - it's definitely doable, and if accomplished would be very powerful, but I expect it's no easy job.
Doable
EMC2Linux - it distributed as a Ubuntu package, which will install realt
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sam0737
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Developers
Thanks. Seems a short pause when the movement stopped but before the extruder is turned off is causing the issue. I need to fix the response time of the M103 command.
Thanks for the idea.
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sam0737
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RepRap Host
Another thing I would try is to swap the driver and stepper. Watch out for the connections too, as the X is moved back and forth by Y, while Y and Z are fixed.
1 hour ago I just had a faulty Z stepper connection (my Repstrap has Y axis moving the toolhead which includes the Z axis), causing my toolhead skipping a layer or two, making squeaking sound and crash into the object being print. Luckily
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sam0737
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Mechanics
I finally got a pool of filament delivered and to play with.
After some try and errors, I finally got a water tight Minimug printed on the 5th trial. But still it is flawed.
Picture 1:
Picture 2:
So as you can see the circle has a bulge, it is where each layer start and ends. I suspect my extruder oozes hence causing this...?
On the other hand, is there any more complicated "benchmark" / "t
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sam0737
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RepRap Host