Show all posts by user
Printing issues ...
Page 6 of 6
Pages: 23456
Results 151 — 174 of 174
It prints! it prints!!!
Though the temperature requires much more tweaking...I found that the sweet spot is really small.
And the raft does curl quite a bit.
But given that it's the first print, I would say it's a success.
My heater seems to be losing heat too fast, for one layer it has to be spend more than 30 seconds to re-heat to the target temperature. I am trying to solve this with easy
by
sam0737
-
Mechanics
For some move, like moving the toolhead into position, or wipe arrival point...I think G0 (fastest possible linear move) could be used.
So it lets the controller determine what's the possible maximum speed, and use the maximum speed, thus saving time.
Moving diagonally and moving purely in one direction has different absolute max speed. It's best to leave the controller to handle that.
I wonde
by
sam0737
-
RepRap Host
I am converting my Linux EMC controlled mini-CNC Mill to a Repstrap, I got the hardware part working now (extruder, driver, firmware...), but then what's next?
In particular, is there any simple object that I can print to verify my machine settings? I don't even know how to use skienforge and tune those parameters!
I hope there was a easier walkthrough to understand how skienforge should be cal
by
sam0737
-
Reprappers
I had some issues with the grips of the motor. The motor is like 20rpm I guess.
So I bought a new one, similar size (so I could re-use the mount!) but at 6rpm. Though the resistance is 10x higher (the old one is 5ohm, the new one is 50ohm), but with the new one it never skip a bit!
At max speed it could extrude at 12mm^3 (if my math is correct...), I hope it could go a little bit faster (may be
by
sam0737
-
Mechanics
My opto isolated + L298 came. Same-day delivery! It happens the seller is also Shanghai based (where I am living).
I hooked it up, change the code to use the Servo PWM pins, and yahoo, It works like charm.
by
sam0737
-
Controllers
Right I am buying a L298 PCB & Parts, which has OPTO for signal lines, 4 Diodes for Back EMF, caps and such...I hope that will do the magic.
"One thing that will likely break an h-bridge, but I dunno about chipped ones, but if two lines go high at the same time"
You mean high side and low side both goes enable? Oh no of course I was not doing that. The A3949 control this logic internally any
by
sam0737
-
Controllers
Nophead, I saw you said that your 100nF disc capacitor doesn't work, but 1nF works.
Is that because of the disc problem? or 100nf VS 1nF makes the differences?
I have solder 3 * 100nF between the terminals, and terminals to the shell of the motor, though I am using the 0805 SMD i have on my hand. Would that help?
Though a bigger issue is I don't have any Diode on my hand, neither the Extruder
by
sam0737
-
Controllers
Cool...I skimmed through nophead's post and seems it might be the cure..A good thing to try over the weekend.
By "blow up", i mean literally, really!. It went into smokes. The chip surface has a hole! Something wrong with the schematic?
The poor thing is I don't have a scope. A Fluke multimeter is all I have...
by
sam0737
-
Controllers
I just recently got my extruder assembled, but then run into problem of random resets when I have the motor connected.
Actually it goes like this:
I had one gear DC motor, 12V 6ohm. I am using Magnetic Encoder, everything is fine except that it's like 30rpm and keep slipping on the filament.
So I decided to buy another gear DC motor. Similar size, totally different brand. 12V 55ohm, 6rpm. But
by
sam0737
-
Controllers
I don't think so. Do you mean because the filament going through the glass transition temperature so it becomes very hard to push in midway?
I don't have this problem in my test (yet). I believe my temperature graident is very steep (given that it's comfortable to touch on the top while the bottom is extruding, even after an hour)...effectively the plastic are either melt, or solid, but not in b
by
sam0737
-
Mechanics
The 3-Axis are driver by some Stepper Controller, which is driven over Parallel Port using Bit-Bang.
For those who is not familiar to EMC...here is what it does in my setup:
1. EMC reads GCODE
2. For movement GCODE, it go through it's "stepgen" HAL (Hardware abstraction Library) library to generate the steps
3. The "stepgen" output is tied, through the HAL system, to the "parport" (Parallel port
by
sam0737
-
RepRap Host
I am converting my DIY CNC Mill controlled by Linux EMC to RepStrap. Changing the toolhead assembly is all I needed while keeping the Axis driving mechanism.
After studying the existing codes, I decided to rewrite...because they assumes I am using Sanguino mobo, but I am actually planning to drive the board with USB->TTL directly from the PC.
I just suspected this might be useful to someone.
by
sam0737
-
RepRap Host
http://picasaweb.google.com/sam0737/HRepStrap
Here are the photos of my extruder, thanks for everyone inspiration!
by
sam0737
-
Mechanics
With a little adjustment to the motor...it's extruding like 50mm/s!
The "heatsink" is getting hotter now after 30mins at 250 degree, but still comfortable to touch.
I think I should go back to work on the program again, before I used up all my plastic stock! It's too much fun watching it extrude.
I havn't looked at skeinforge and AoI yet, oh..also the M-Apps. Yeah! I'm over-joyed.
by
sam0737
-
Mechanics
Today I finally got the heater assembled, and I got my first filament extruded!
I found that the pressure inside the nozzle acts as a very good low pass filter...hence the PID really doesn't have to be so accurate.
My gear is not tight enough though, it's keep slips if the speed is >5mm/s.
Let me have the machine cool down and try to do some adjustments-
by
sam0737
-
Mechanics
Oh the resistor from RS and the thermal blocks finally came back.
I spent a few hours to hook them up. No drill, no cement, just assemblying and hey, it works!!
I got my very first filament extruded! Albeit the motor can't get the plastic so I could only extrude like 5mm/sec.
The top of the SS pipe is even cool to touch, a little bit fuzzy warm but won't get hotter than my laptop. I think that
by
sam0737
-
Mechanics
---------Some unimportant BS---------
The Al motor mount parts came back from the workshop. minor issue during assemblying because I am not aware the controller board is actually that TALL and hence those designed mounting position doesn't work. Nevermind, at least the magnetic encoder is positioned correctly.
I rewrote the firmware, I rewrote the EMC2 HAL userspace driver, the pyvcp UI. I don't
by
sam0737
-
Mechanics
Oh...it's really prints like a 2D printers!
See the color cartridge? It's just standard HP inkjet color cartridge! (I think they license their technology?)
And I think somehow the inks react with the powder so they forms solid.
But then it's not plastic right? I suspect the strength of those powder formed thing will be much less than ABS.
UPrint is also interesting, I think it prints like Rep
by
sam0737
-
General
Convertingmy CNC Milling to RepStrap is what I am working on.
I made that CNC milling by myself, and it's controlled by EMC2 (linuxcnc.org). Parallel port is used to signal the stepper drivers and controlling the axis, as well as the spindle, end stops.
I am going to just add a extruder controller, and hook it up with USB->TTL cable. The EMC2 software will still take care of the G-Code and t
by
sam0737
-
Controllers
Oh yes! The article just came in time!
by
sam0737
-
Mechanics
Looks like SS as thermal barrier + enamel resistor heater seems to be promising.
After reading a reader comment on Nophead's blog about it's AL Shell resistor exploding...I decided to go with Enamel resistor.
I have spent a long time on Taobao.com (Think it as better-than-eBay in China) but couldn't find a enamel resistors with axial output, luckily the RS-China carries similar enamel resistor
by
sam0737
-
Mechanics
I was sourcing for the resistors...
However, the enamel resistor I have found around doesn't have axial connection, but comes with a base instead...
I am also looking at aluminium case Wirewound resistor, however they are rated at 200 degree C. I don't really understand what it means...will it disintegrate when reaching that temperature? shorts and catches fire? or just inaccurate resistance va
by
sam0737
-
Mechanics
I am trying to make a RepStrap. I have a 3-axis machines working with Linux EMC, now all I need is the Extruder.
--- The story is... ---
The thing is - I don't have any power tool with me except a crappy drill. No drill press, no drill, no lathe, limited hand tools. I am not planning to acquire them either. But being living in China right now, it's affordable to have parts professionally machin
by
sam0737
-
Mechanics
I have been reading the Thermoplast Extruder Version 2.0 and planning to build one for RepStrap. I have minimum access to power tools and so far I am trying to avoid any mechanical work except for assembling, or if unavoidable send the design to workshop...
My question is, what's the fire cement and the copper jacket for? Are they crucial in the design? Is that only for insulting the heat from
by
sam0737
-
Mechanics
Page 6 of 6
Pages: 23456