Show all posts by user
Printing issues ...
I went to Carrefour store and figure out an USD 2 solution.
* A 30cm dia. plastic basket
* a curved, thin melamine bowl
Tape the bowl to the bottom of the basket, such that it can spin acceptably free. Then with a long stick lying around, it feed the filament from the above.
Like this:
by
sam0737
-
General
I have done exactly that...I originally built an CNC as an hobby (mainly for milling PCB ), and discovered Reprap and think it's more fun to play.
Now I'm in the tuning phase.
My Mill:
My RepStrap:
I use EMC2 , it runs on Linux so it's free. I run it on an Ubuntu on my old Thinkpad T40 laptop (6 years old Centrino laptop).
I don't think the Mach3 could do the job, as EMC2 offers some very cr
by
sam0737
-
CNC Routers, Mills, and Hybrid RepRapping
I finally got my order of 50kg of ABS 3mm filament. (USD 3.6 per kg, min order 50 kg)
They are packed as 10 rolls, 5kg roll. What I didn't expect is how big a 5kg roll is! It's as big as a CAT5 cable boxes, and actually even a little bit thicker than that.
Besides Sky-Hook made by nophead, what do you guys use to mount that beast?
Sky-hook is not an option because my apartment is rented, and th
by
sam0737
-
General
---Sorry I am afraid I hijacked your thread for a different topics.
Totally understand, Enrique.
It's very hard to go from 1 person, to many people.
I also understand that there are many other works that can be done to make RepRap even better, say personally I would love to see we could extrude of make filament from granules, I had a hard time to source the filament.
Though, people have differ
by
sam0737
-
Skeinforge
(Sorry no Settings, because I didn't finish my tuning yet )
Hi Enrique,
Is that possible that you could put the source code over GitHub (or whatever GIT), so that people (I mean..me!) can fork and contribute easily, and that you can also cherry-pick and integrate them back to the official release?
There are many places here and there that I would like to hack/improve...I am not sure what's the
by
sam0737
-
Skeinforge
Finally, after digging through the Web, I found a supplier on Alibaba which sells what I needed -
Oh. To be honest, actually I should credit talcite's post:
But the minimum order is 50kg, so I did. Obviously too much for me, but at 25 RMB per KG (~3.66 USD, 2.51 EURO, 2.19 GBP), that's marginally affordable.
I hope I could resell some through eBay or Taobao . Though I am unaware of any othe
by
sam0737
-
General
Haha. Nice suggestion but I don't drink.
So at the end, my first printed, usable object is a cooling fan mount for my repstrap.
by
sam0737
-
Reprappers
A hopper extruder that accepts plastic in granule form! Not necessary in one part, could be hopper/extruder that produce 3mm filament than feed into the existing extruder.
I think this would reduce the running cost a whole lot...! Especially for those who can't get filament cheaply.
by
sam0737
-
General
And I changed my heater to 3.9ohm wirewound resistor, down from 6.8ohm. The 6.8ohm can't give enough output to combat with the heat loss.
I think there are something we can do in the firmware to combat with loss thermocouple. Say if the temperature wasn't raised for X degrees C in Y seconds, something is going wrong (a loose thermistor/thermocouple) and hence e-stop should be triggered.
by
sam0737
-
Mechanics
Oh. I think I misunderstood.
So it's just merely a check during wipe, instead of live monitoring while printing? This should be much easier.
I thought you want to do live monitoring of the flowrate, then feedback to slow or speed up the toolhead movement feedrate in ratio.
Though I am not sure about the usefulness. We should really fix the PTFE design if that was that easy to fail (Sorry I do
by
sam0737
-
Mechanics
The code are actually almost in place,
The difficult part - DIP, manage_motor1_speed() is actually hooked up.
The only things that's missing is increasing the speed_error. Which is yes, should be done in the Timer.
I have rewritten the firmware for my Extruder controller at
You could copy the code if you wish, it's GPL. It's designed to talk with EMC2, but using the same compatible protocol
by
sam0737
-
RepRap Host
So in a Darwin it is always extruder flowrate bound? Then that would make sense.
As you can see , my RepStrap is all metalled. Even if it's driven by ballscrew, there is a lot of inertia (plus the friction is somewhat high, or my motors are not beefy enough.) As a result, the max speed for one axis is 900mm/s, another axis is 1200mm/s. The max acceleration are about 200mm/s/s...Which is fast eno
by
sam0737
-
RepRap Host
Nevermind about packaging. I got it running...oh my, it's much easier than thermistor except that it requires one more little piece (and pretty pricey) PCB and a few wires.
I spent 15 minutes on the noise though. I forgot the motor is grounded to my toolhead, and the thermalcouple is not isolated. Then when I spins up the motor, the measured temperature jumps -50 to +50 around the real temperatu
by
sam0737
-
Mechanics
Oh wait. What's grogyan suggesting is interesting - the optical mouse.
The optical mouse that we use everyday now on unmarked table, or even glass for some model. The one that we though unachievable 10 years ago and requires a marking mat to use.
Two issues I can think of:
1. how are we going to mount it? There is no headroom below the nozzle because the nozzle needs to press against the molten
by
sam0737
-
Mechanics
I have a Magnetic encoder DIP extruder motor, but I think skeinforge is not making full use of it.
From what I observe, the flowrate is back-calculated by the maximum feedrate and that's it. That's ok because the machine is ultimately feedrate bound, but when printing the raft-base, the speed is limited by the flow rate, and even my machine is capable at higher flowrate, it doesn't go up. The ve
by
sam0737
-
RepRap Host
I don't have a GM3 nor that suppression board...from the photo in the Wiki, I think it will be just exactly what it says - melt a whole lot of solder into the hole will do the job.
Lining it up to the edge might it works easier, but be sure not the break the tabs by bending too much
by
sam0737
-
Controllers
I don't think you have to. It's just a spare holes that in case someone wants to use a jumper instead of screw terminal.
It doesn't hurt if have them accidentally soldered, no worry.
by
sam0737
-
Controllers
oh. I finally digged out some older post and blogs. Look like we are still far from success.
The nearest thread I found is
I doubt if the recent "breakthrough" findings of stainless steel barrel and thermal barrier can be applied here or not. Hm...
by
sam0737
-
Mechanics
Yes indeed it's a RepStrap. Because I had made a milling machine, so it's just logical to covert the toolhead from a drill to extruder.
Plus, I am not aware of any China, or even far east, reprapper! Check the google map , I am the only one.
Which means getting someone to print the parts for me...I would have to eat the shipping cost.
Using skate bearing to measure the extruding material? I do
by
sam0737
-
Mechanics
I have a real hard time in getting the filament. Even harder to get PLA.
I found a lot of merchant selling them in granules, which could be ordered in much affordable quantity. For 3mm ABS filament form, the min order is like 50 to 100kg.
Even worse, I have yet to found anyone who will make PLA filament!
I heard some people were working on hopper extruder? Is there any update to that?
I also
by
sam0737
-
Mechanics
I found myself in a very embarrassing situation. I couldn't find a PLA/ABS filament source yet.
I live in Shanghai at the moment, I wonder if there is any other reprappers in China.
The thing is - it's easy to get 1 meter long filament, it's selling everywhere, but over 1 meter? No...
Or you can get customize to 3mm filament directly from factory, but with minimum order of 100kg, and each Kg i
by
sam0737
-
General
For the thermocouple chip,
What is the difference between AD595CQ (Cerdip) and AD595CD (TO-116)?
They are just the same footprint, with one of them have a metal plate over it. Functionally what are the differences? Which one is better?
While I am waiting for the thermocouple and chip, I milled my first usable PCB!
#
(Surely it could be faster and easier with wire-wrap board, but I don't have on
by
sam0737
-
Mechanics
Oh. I didn't know that thermocouple output is linear. (or I actually read that but I forgot)
Now I am going to buy a thermocouple-K and AD595 and see how it goes.
by
sam0737
-
Mechanics
....Background....
Yesterday when I was printing, I found that the temperature reading jumps from 258 to 270, with nothing in between. (I know 258 is very inaccurate, it couldn't be that hot)
Later I found that the table generated by
./createTemperatureLookup.py --r0=6360 --t0=100 --r1=0 --r2=4700 --beta=3990 --max-adc=1023
Just do not give enough resolution at the first band.
Now I solder a
by
sam0737
-
Mechanics
Blogs...
Swell and elongated.
PTFE barrel is not very forgiving when thing fails. You need a new one.
See the tag / ring below of the PEEK thermal barrier? It's there to hold it in place and not popping out, or else when thing gets hot, it expand a lot.
My gut feeling is that it won't work for long, and when it fails replacement would be needed.
Plus, I have no where to know where I could
by
sam0737
-
Mechanics
I actually wonder if PTFE rod is a good design. I have seen too many blogs writing about mechanical failure of the PTFE rod, and recently I saw quite a few blogs trying to use Stainless steel + Heatsink as thermal barrier (or create sharp thermal gradient).
Those are RepStrap though, not RepRap.
I thought PTFE rod design is optimized for home-made, one without access to machine shop. But if you
by
sam0737
-
Mechanics
For the sake of completeness, I am attaching the drawing.
by
sam0737
-
Mechanics
I am using skeinforge and feed its GCode to Linux EMC to my RepStrap.
During the print, I saw the machine walking around the boundary of the object without extruding. I think it's the "orbiting" mentioned in the doc? (I don't know what does it mean yet)
What the purpose of doing orbiting?
by
sam0737
-
Plastic Extruder Working Group
I am going to answer my own question.
I sit down, and took an hour or two to read through every plugins' documentation.
My conclusion is that - for those parameters that has to be tweaked, they are very easy to understand and well documented. For those complicated matter, the default are most like fine.
The craft sequences are stored in skeinforge_tools/craft_sequences/ file. It's a good place
by
sam0737
-
Reprappers