Show all posts by user
General discussions. For specific printers / electronics / fabrication methods / softwares, please see other sections.
Re: How to hold the bed down? - 10 years ago
Great idea, Ray! I'll go out and get one of those photo frames.by dc42 - Ormerod
Re: Temperature - 10 years ago
It sounds as though you haven't connected the thermistors to the Duet. Have you plugged everything into the Duet, as shown at the bottom of this page?by dc42 - Ormerod
Re: Network connection - 10 years ago
There are a couple of things you can check: 1. Check that there is a jumper across the "5V EN" pins on the Duet board. See attached photo. If there isn't, DO NOT add a jumper in this position until you have done the next check, or you risk destroying some components on the board. 2. Check that components R60 and R62 next to that jumper are the right way round as on the photo, i.e. at right anglby dc42 - Ormerod
Re: Duet 3.3V supply quality - 10 years ago
I agree, it doesn't look easy to add a big capacitor in parallel with C3. However, I've found 470uF 25V and 680uF 16V SMD capacitors that will probably fit in the C3 position, and 330uF 16V caps that will definitely fit. I'll add some to my next Farnell order. Or maybe just get an ATX PSU with better resistance to brownouts.by dc42 - Ormerod
How to hold the bed down? [SOLVED] - 10 years ago
Has anyone found a good way to hold the print bed firmly on the heat spreader and not slip? The foldback clips don't work for me even if I just clip them over the edge, because on the end of the bed nearest the Y-motor the fan housing fouls on them, and at the other end the IR sensor fouls on one of them. So only 1 of the 4 clips is usable on my Ormerod. I tried attaching the bed with Kapton taby dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
QuoteRory166 Yes I see that using FanO requires 12V, although I assume it would work with a lower voltage than it is intended for(all rails share the same common?). Yes, however according to the schematic there is a led + series resistor connected between +12V and the fan output. So even if you use the fan output to switch the sensor led from the 3.3V supply that is already routed to the board,by dc42 - Ormerod
Re: From this to this in 3 days ! - 10 years ago
Quotehughesie I can't wait for the 3 colour head , I emailed Reprappro asking when it would be out and was told not in the near future. I was speaking to a supplier of filament today, and he said he will soon be stocking a PVA (?) filament that dissolves in water. The idea is that you use it to support large overhangs etc. and then dissolve it away. It sounds interesting, but obviously you wouldby dc42 - Ormerod
Re: Duet 3.3V supply quality - 10 years ago
QuoteRory166 I like Ian's post above which I only read after fitting the cap. Feed the 5v rail from a 5v output of the psu. Let the poor old 12v take a right bashing from the switching transients. For that matter the psu also produces up to 30A of 3.3V so why not use that ? I like the current scheme of deriving the 3.3V supply via a linear regulator from a 5V supply. A linear regulator can pby dc42 - Ormerod
Re: Duet 3.3V supply quality - 10 years ago
I've been thinking about this a little more: 1. Adding extra capacitance to the output of a switching regulator should be done with care. From the A4403 datasheet: QuoteThe output capacitor determines the output voltage ripple and is used to close the control loop. As outlined in the Control Loop section, the bandwidth has been optimized for an output capacitance of 20 μF. If a particular appliby dc42 - Ormerod
Re: From this to this in 3 days ! - 10 years ago
Very nice! Where did you find the design? How long did it take to print?by dc42 - Ormerod
Re: Duet 3.3V supply quality - 10 years ago
Radian, that's very interesting! One other thing I notice is that the Duet implementation of the A4403 5V regulator circuit omits the capacitor in parallel with the feedback resistor. Although the datasheet says this is an optional component, without it the transient response is worse, and the feedback input of the IC is more susceptible to noise pickup (e.g. if any of the stepper motor cables goby dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
Hi Rory. Yes I would expect bright sunlight to be able to overpower a 50W halogen lamp. But it's winter so the sun is not very high, and it was well past midday when I observed the effect. Also my windows are double glazed, and modern double glazing has a thin metal film on the inside of the glass to reflect IR. I'm not even sure the sun was shining directly on the print bed. These factors may eby dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
Quotechriscain You could use the FAN0 output on the Duet it's connected to the PWM o/p pin with a mosfet and not used on the Ormerod as the fan is on all the time. would need a higher resistor as it's on the 12v supply. That's certainly a possibility, although I'm a little concerned that unless I load the power mosfet heavily, it might be very slow to turn off - which might not matter, dependinby dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
Hi nof, According to the specs of the Arduino Due on which the Duet electronics is based, the most current that any of the pins can supply is 15mA source or 9mA sink. I'm running the LED at 40mA to increase the IR output and thereby decrease the effect of ambient light. Even if I accepted a reduction in current to 15mA, I still think that direct drive wouldn't be such a good idea, because the voby dc42 - Ormerod
Re: Problems with flow rates, extrusion etc - 10 years ago
My hot end registers either 5.4 or 9.8C at room temperature, which is about 20C where I have the Ormerod. It sounds as though yours is 2 quanta of measurement lower at room temperature than mine. I guess it's not impossible that you have a dud thermistor, or that you overcooked it while shrinking the PTFE sleeving on. I would ask RepRappro for another thermistor + heatshrink. But a blockage is ceby dc42 - Ormerod
Re: extruder drive - 10 years ago
I don't think there is any blockage. Printing generally works OK, I just think it's trying to extrude the filament faster than it wants to melt. I'll try a lower feed setting or a higher temperature.by dc42 - Ormerod
Re: Fan backwash causes warping? - 10 years ago
Ah, I had missed the fact that there was already a 5mm long duct.by dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
I've already tried sliding a 4th wire into the sheath of the sensor cable, and it fits easily. I'm planning to either epoxy a 4th header pin to the board, or solder a 4-way header strip to the existing 3-way header strip to make the 4th connection. I would design and order a pcb that incorporates the extra circuitry, but I expect RepRapPro will do that soon enough anyway. So for now I'll just solby dc42 - Ormerod
Re: Network connection - 10 years ago
Have you tried using a different IP address? Some routers like to manage IP addresses in a certain range via DHCP. I changed mine to 192.168.1.80. Also, does the gateway IP address in config.g match the IP address of your own router? I don't know if it matters, but I changed it to the IP address of my own router before I tried connecting.by dc42 - Ormerod
Re: Fan backwash causes warping? - 10 years ago
I'm wondering (and I think I mentioned it in another post) whether a 10mm thick fan separated from the heatsink by 5mm or 10mm spacers would provide better cooling and less backwash. With the fan right against the heatsink, there will surely be no airflow near the centre or the corners of the heatsink.by dc42 - Ormerod
Re: Network connection - 10 years ago
When I connect via Ethernet, I always see the control page briefly before the login page appears. So I think this is normal behaviour.by dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
Yes Chris, that is exactly what I was going to do, along with adding a transistor to drive the led from an output pin. The SAM processor output pins can't supply much current and I am running the led at 40mA.by dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
Hi Rory, Yes I wanted to add modulation to the IR emitter, however the firmware needs to be changed for that and I can't build the firmware at the moment (it doesn't build under Arduino IDE despite having a .ino file). So for now I have been limited to changing component values.by dc42 - Ormerod
Re: questions about building - lnear bearings oil? and glue x-axis acrylic? - 10 years ago
1. Re gluing acrylic, I understand that you need a special glue for this (acrylic monomer) because most adhesives won't adhere well to acrylic. 2. Re allen head screws, after assembling a few joints I went out and bought 2mm and 2.5mm hex drivers, because I realised it would take an age to assemble all the joints using allens keys. I think this should be recommended in the build instructions. Onby dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
Hi Ian, I made 2 resistor changes: 1. Reduced the LED drive series resistor from 160 ohms to 51 ohms, in order to increase the current from 13mA to 40mA. This increases the light output by a factor of about 3, and thereby decreases the effect of ambient light by a similar factor. 2. Reduced the phototransistor load resistor by a factor of 5.5. This is partly to compensate for the IR output havby dc42 - Ormerod
Re: Improving the proximity sensor - SUCCESS! - 10 years ago
PS: 1. The sensor part number is TCRT1000, not TPRT1000 as I said in my original post. Datasheet here: TCRT1000 2. For anyone else contemplating this mod, I now think the 2.7K load resistor I used could be increased to about 3.9K or perhaps even 4.7K. The important thing is to make sure the reading at the Z-distance you want to use for calibration is below 700.The sensitivity drops off when theby dc42 - Ormerod
Re: Servo driver heatsink? - 10 years ago
You mean the stepper motor drivers? If they are the A4988 as used on previous RepRaps, then at the 800mA current programmed into them in config.g they should not need a heatsink.by dc42 - Ormerod
Printer stopped before finishing print - 10 years ago
I've just done a lengthy print job, and the Ormerod stopped just before finishing. It has either finished or nearly finished laying down filament. It didn't execute the standard commands at the end of the gcode file to move the print head and turn off the heaters, it left the print head in contact with the work and the heaters on. Has anyone else experienced this?by dc42 - Ormerod
Re: x axis carriage 9mm bearing not free - 10 years ago
Regarding "dished washers": because of the way washers are made (pressed from sheet metal), they are typically not quite flat. So if you lay one against a flat surface, either the inside or the outside will be in contact with the surface, depending on which way up you put it. The ones I received in the Ormerod kit were indeed not flat, but slightly dished in this way.by dc42 - Ormerod