Show all posts by user
Re: Fine threads and rough edges when printing - 12 years ago
QuoteRory166 Not a "disaster darling" its a work of art. Call it "My Vision of Chaos" and enter it into next years Turner prize, should be a shoe in, don't forget I'm due a drink when you win the 25k prize. QuoteRory166 I have now completed a prototype deflector had intended to use aluminium but some clear plastic was the first thing that came to hand. At least you can see what it is, easierby dc42 - Ormerod
Re: Fine threads and rough edges when printing - 12 years ago
I did a print at 200C (first layer 205C) with retraction = 5mm @ 45mm/s and this is how it turned out: That's the best yet. The extra retraction distance and speed appear to have solved the stringing problem, I just have a few small lumps and two detached threads. I then did another print with the temperature reduced to 195C and this is what happened: Another Turner Prize entry. The head hby dc42 - Ormerod
Re: Setting temp from web interface - 12 years ago
I find that I can connect fairly reliably via the web interface, provided I don't also have a USB connection (and I can connect sometimes even then). I've had prints stop twice. Once, it happened right at or near the end of a print, and I suspect either a power brownout or a firmware problem. The other time, it turned out that I had forgotten to re-tighten the terminal block screws after disconnby dc42 - Ormerod
Re: How to hold the bed down? [SOLVED] - 12 years ago
I found this supplier. The "Swiss clips" look ideal to me. It might even be possible to redesign the heated bed PCB with holes for them to lock into (if that doesn't make removal too difficult).by dc42 - Ormerod
Re: Fine threads and rough edges when printing - 12 years ago
Thanks! The retraction rate is set to 30mm/sec at present, so I'll try increasing it to 45. Also I read this in the slic3r manual: QuoteLength - The number of millimeters to retract. Note that the measurement is taken from the raw filament entering the extruder. A value of between 1 and 2mm is usually recommended. Bowden extruders may need up to 4 or 5mm due to the hysteresis introduced by the tby dc42 - Ormerod
Re: Fine threads and rough edges when printing - 12 years ago
Ian, thanks again. The slic3r manual section on Fighting Ooze looks especially interesting. What is the maximum extruder feed/retraction rate supported by Ormerod?by dc42 - Ormerod
Re: Setting temp from web interface - 12 years ago
I find that although the temperature you enter in one box is copied to the other box, it doesn't change the set point for that temperature. But it's confusing, and I hope this will get sorted out in a firmware revision soon. btw I also couldn't get the "Send GCODE" function to work.by dc42 - Ormerod
Re: How to hold the bed down? [SOLVED] - 12 years ago
Thanks, Ian! Sounds like I had better stick to mdf or hardboard for the tabs then.by dc42 - Ormerod
Re: Fine threads and rough edges when printing - 12 years ago
Thanks, Rory. I tried 190C and it was a disaster: Trying 210C now.by dc42 - Ormerod
Re: Parts list - 12 years ago
I would like the manufacturer and/or Farnell part # for the 3-way header socket connector shell, so that I can replace the 2-way ones supplied with early kits for the hot end fan and y-axis endstop looms.by dc42 - Ormerod
Fine threads and rough edges when printing - 12 years ago
I've done a few prints now but there is a consistent problem. When the print head moves (without extruding) between different areas of the print, PLA is sometimes still coming out of the extruder head. As a result it leaves lumps on the piece of work it is leaving, and fine threads connecting different parts of the print. This piece shows the problem, although there were originally many more filaby dc42 - Ormerod
Re: How to hold the bed down? - 12 years ago
QuoteRory166 Superb pictures, what sort of camera do you use? Galaxy S4 smartphone camera. It's a bit temperamental when trying to focus at short distances, otherwise OK. QuoteRory166 I suspect the MDF pieces go the other way up than shown in picture with cardboard. No, they go that way up. Like I said, the glass+alu+pcb+mdf is a bit thicker than the clips are intended for, but it did fit - seby dc42 - Ormerod
Re: What's inside an ACE ATX psu - 12 years ago
Rory, If I change the driver transistor for one with a higher Rds(on), then that Rds(on) will limit the rate at which the driver mosfet sucks charge out of the gate of the power mosfet to turn it off, and thereby slow down the turn-off. However, I now think it would be possible to cut the power mosfet gate leg and solder a 0603 resistor between the leg and the pad. By my calculations, a 100 ohmby dc42 - Ormerod
Re: Embedded images from Dropbox don't work - 12 years ago
Reaper, thanks very much, that fixed it for me.by dc42 - Administration, Announcements, Policy
Re: What's inside an ACE ATX psu - 12 years ago
Hi Radian, I've been thinking about your suggestion of a snubber network, and I think a diode-capacitor-resistor snubber could work well. I've connected a flyback diode in parallel with my bed heater (see this post). The flyback diode stops the mosfet avalanching (which wasn't really a problem anyway), however it does nothing to avoid the transient on the 12V supply due to sudden cutoff of the 1by dc42 - Ormerod
Re: Duet 3.3V supply quality - 12 years ago
Quotedroftarts @dc42: Is it just me, or does everyone else get "Image error, Running getimagesize() on the image data failed" on your pictures? They don't work in Firefox, Safari or Chrome on Mac... Ian RepRapPro tech support Hi Ian, I've solved the image error problem by only using links to my Dropbox public folder, and I've updated all the relevant posts that had this problem.by dc42 - Ormerod
Duet firmware updated - 12 years ago
I just checked the Duet branch of RepRapFirmware and found it was updated yesterday. I see the following changes: - 5ms start-up delay added - Support for commands M98 (call subprogram) and M99 (return from subprogram) added. So nothing very significant for most of us, except that the start-up delay should help those who are using the original SD cards.by dc42 - Ormerod
Re: Duet 3.3V supply quality - 12 years ago
I would add to Ian's comments that I've only had printing stop unexpectedly once, and the mains power where I am has been a little flaky during the high winds over the past few days. Ideally I'd get a UPS, but that is beyond my budget right now. Hence one of my mods is aimed at improving tolerance of brownouts. The 3.3V supply on my board appears to be stable when the bed heater turns on/off, soby dc42 - Ormerod
Re: Duet 3.3V supply quality - 12 years ago
1. I've just checked the 3.3V supply with a DMM across pins 2 & 3. It reads 3.28V whether the bed heater is on or off. So I think the apparent drop in the 3.3V supply on the scope when the bed heater goes off is caused by the fact that ATX supplies have the 0V line connected to mains ground. which unfortunately means you get a ground loop when you connect a scope earth lead as well. 2. Radiaby dc42 - Ormerod
Re: Duet 3.3V supply quality - 12 years ago
Further to my earlier post regarding the noise I see on the 3.3V rail when the bed heater turns off, I disconnected the scope probe that I was using to trigger from the mosfet drain signal and nearly all the noise went away. So it seems that what I was seeing was coupling between the scope probes via the (short) common ground wire I was using to connect to the scope prove earth clips to pin 2 ofby dc42 - Ormerod
Re: Duet 3.3V supply quality - 12 years ago
Quotedroftarts @dc42: Is it just me, or does everyone else get "Image error, Running getimagesize() on the image data failed" on your pictures? They don't work in Firefox, Safari or Chrome on Mac... Ian RepRapPro tech support Hi Ian, I've complained about it here.by dc42 - Ormerod
Embedded images from Dropbox don't work - 12 years ago
If I try to link to my images hosted on Dropbox, then in place of the image in my post I get an "Image error" message. Here is an example: I think this is because Dropbox links are https, and Phorum doesn't understand https. If I change the https: to http: then I get this instead: Is there a workaround? Can anything be done to allow images on Dropbox to work in these forums? I don't want toby dc42 - Administration, Announcements, Policy
Re: Duet 3.3V supply quality - 12 years ago
Here are my photos of the 5V and 3.3V supplies when the bed heater is turned off (yellow trace is 5V or 3.3V, blue trace is mosfet drain voltage which I used to trigger the scope): This is after I did the mods I listed in my previous post. The 5V and 3.3V transients are not very different, so I believe they are mostly caused either by the scope probe and its earth lead detecting the magneticby dc42 - Ormerod
Re: Duet 3.3V supply quality - 12 years ago
Radian, I attached a scope to my Duet board to see if I can replicate your observations. This is what I found on the mosfet drain: As you say, there is a 50V spike and the mosfet is avalanching. Here is the voltage on the 12V input, measure directly between the screw terminals: I don't see a 20V spike, the peak is a little under 14V. I did see a bigger spike when I connected the scope earthby dc42 - Ormerod
Re: Duet 3.3V supply quality - 12 years ago
QuoteRory166 I would like to examine the circuit diagram of the duet but am unable to access through github, possibly due to my use of a Mac. Are you able to direct me to a copy? I need this to use my scope onth eboard to confirm your results are universal. Rory, if you PM me your email address, I'll email you the pdf.by dc42 - Ormerod
Re: What's inside an ACE ATX psu - 12 years ago
QuoteRadian I also thought you'd mention a snubber network across the load ;-) 1uF/10R seems about right 10R would be too low, 2R would be more like it, that would limit the peak mosfet drain voltage to 12 + (2 * 11.3) volts. But since we don't need to reduce the rise time of the drain voltage, just reduce the amplitude of the spike, a flyback diode is simpler and avoids increasing the turn-on tby dc42 - Ormerod
Re: How to hold the bed down? - 12 years ago
I've completed this mod and it appears to work well. Here are some photos. First, the 59p frame kit: After cutting 4 tabs from the slotted MDF: After lengthening the slots in the bed insulator to 30mm: After fitting the glass, heat spreader and mdf tabs together with the clips: After attaching the bed assembly to the carriage, using 20mm cap head screws and extra nuts: I found that I waby dc42 - Ormerod
Re: Printer stopped before finishing print - 12 years ago
The processor has a builtin watchdog timer that can reset the processor if it isn't kicked for a while. It should be a simple matter to enable this in the firmware, along with a status indicator to indicate whether the last reset was caused by power on, reset button, or watchdog. Ian, are there any forums where we can suggest improvements to the Duet firmware, and improvements to the Duet electrby dc42 - Ormerod
Re: What's inside an ACE ATX psu - 12 years ago
If the hot bed takes 11.3A then it deserves some serious decoupling caps right between the +12V feed to the hot bed and the source terminal of the mosfet. As opposed to no decoupling caps at all, as on the present designby dc42 - Ormerod
Re: Network connection - 12 years ago
Arnaud31, just in case the problem is between the router and the Duet, it might be worth connecting the Duet directly to your computer, disconnecting the computer from the router, and manually setting the computer IP address to one on the same subnet as the Duet.by dc42 - Ormerod