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Hi there. I have a problem my servo keeps moving every 1 or 2 minutes nonestop. do anybody knows what could it be. I have switch the servo already and still the same thing. I have a video to show the problem https://www.youtube.com/watch?v=3LVj4T71T4I
There is a problem where the servo can twitch. There are a couple of things that can be done about that. But the movement you have is much more than a twitch. I haven't seen that much movement before.
FWIW, I hesitate to post this as it makes no sense as to why it solved the same problem but here it is. I used the same microswitch you have as it is the recommended switch and had the same movement as you except it was downward instead of up. Mine moved down probably because with my servo I had to use 10 as the down position and 100 as up which is backward from what is generally used for some reason. I went through two of the recommended switches due to very unreliable bed leveling behavior, I had to watch it like a hawk. I finally used the z switch that came with the makerfarm ( the one with an arm ) and after many prints I have had perfect reliable auto bed leveling and no movement like yours (knock on wood) during the print. With the recommended switch I had to unplug the servo after bed leveling to stop the movement. No more! Like I said - FWIW.
I've been waiting for this to come up here, had this problem last Summer. No one on any of the forums I frequent had a solution, several diagnosed it as RF interference, but none of their suggestions fixed it. I limped by for a month until it caused a particularly catastrophic print failure (ripped the probe off and almost started a fire). After weeks of Googling I still couldn't find any answers, but then I located this post. That is your answer, ABL has worked like a dream ever since. If it does work for you, be sure to thank jamesdanielv; that's the only real solution to this problem I've ever seen.
What worked for me: Getting rid of the towerpro servo and getting a better quality 9G servo, and rearranging the wires to be differently bundled together.
My servo has a little occasional twitch too, but my servo arm is shorter than yours so the twitch doesn't seem to great. I'll follow the post.
Am looking for a better servo. Can you link me to the one you bought if possible. Thanks.
Quote:
Originally Posted by TopJimmyCooks
You can use the Hitec Hs55 Servos, ...mine seem to be working excellent. here is link to amazon
http://www.amazon.com/Hitec-31055S-H...rds=hitec+hs55
Hexatronics HXT 900 here. looks the same as the towerpro but holds up much better. If buying again I would go for one with metal gears.
Bought it. Let's see if that helps. Hope it does. Also bought some red abs the one I got from makergeeks had too much bubbles. And I want to print the Itty bitty flex with no problem and good quality.
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Originally Posted by voodoo28
I too had trouble with Makergeeks ABS.Quote:
Originally Posted by rhonal89
I think the Metal Gears might actually be too strong in case of a bed crash...could break your X Carriage instead of the servo giving way...Just a thought. Then again...the torque of the servo is not much. :confused:
Quote:
Originally Posted by TopJimmyCooks
My ABS was a surprise package. Not sure if that had anything to do with the quality they send you. Maybe that's the way they get rid of the bad filament they have. I'll give your servo a try. Hope that fixes the problem. For now I have another servo left to try.
Quote:
Originally Posted by voodoo28
Good find! And here is some more info: https://github.com/MarlinFirmware/Marlin/issues/1885 This thread references a thread at the Arduino group where the root problem is discussed: http://forum.arduino.cc/index.php?topic=312869.30Quote:
Originally Posted by misquamacus
If this 'twitching' is happening on every print, this may not be the issue. (But it could be!) What is happening is there is a 'bug' (The Arduino group says it is not a bug) where the detach() function doesn't check the state of the control signal going to the servo before disconnecting from it. If it is disconnected while in a high state some bad things happen. First, the last pulse of the pulse train going out to control the servo never ends. Or, from another perspective the control line stays high instead of being low like (some people claim) it should be. There are no standards for how these R/C servo's are supposed to do things. Depending upon the brand (and how much money you spend) you are going to get different behavior.
This is marked as a 'bug' and Marlin is going through a bug fix phase right now. I suspect in 2 or 3 weeks this will be ironed out. But for right now, here is something else you can try instead of switching servos. You can try changing the retracted and engaged angle numbers by one or two or three in each direction. Probably, you will be able to find a number where it is stable. I had to do that with my cheap eBay Tower Pro servo (that cost me $4.75 with shipping from China).
I guess is what you just posted. It doesn't happen on every print sometime I'll would print 2 or 3 items next print the servo would be crazy. Sometime the servo arm would move more than what you just sow on the video. Thanks for the info. And autobed level sometime don't work look at adamfilip he created a thread also. I posted some video. But I can deal with that stop and restart until it works.
Quote:
Originally Posted by Roxy
This makes sense now for me. When I switched microswitches my extend/retract numbers changed a little bit which is probably the reason my movement problem went away! I still had other crazy things during the auto bed leveling sequence that were also solved when I got rid of the recommended microswitches.Quote:
Originally Posted by Roxy
I received the servo voodoo28 recommend and am still getting the same servo movement. Exempt this time is down. Servo is backward. I did couple of changes to the page roxy posted and no luck. Could it be something with marlin 1.0.2. That's the only firmware I have try other than makerfarm. I try roxy one and when it flashed servo twitches like crazy. I guess bad configuration on my part on that firmware. Also changed the value by one and still happens.
Have you tried the Marlin from Clough42' site? You could use the Itty BItty single extruder ..and just change the E steps to match your original and make any other changes needed. I am currently using the Flex Extruder Marlin form his site. If you want to..PM me your original Marlin Config and ill try to match it up for you with the version from C42's site.
Alright thank you!! Am on my way to work right now. Let me try what you said when I get home today. If am still having trouble I'll send you a pm.
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Originally Posted by voodoo28
Ok no prob, What board do you have?Quote:
Originally Posted by rhonal89
I have the rambo.
ok perfect, we have the same setup. That will definitely help! ;)
Quote:
Originally Posted by rhonal89
Sharing my configuration.h and pins.h files to be looked at. I just updated to clough42 and it seem when I autohome it goes the opposite way. crashed!! Also sharing my pins.h Looks like is also crazy on the servo update for rambo. Send PM to voodoo28.
If you need to switch the direction of any axis, that is very easy to do in the Configuration.h file. Why don't you also post the Clough42 configuration.h file and I'll compare them. Besides inverting the various axis, the configuration.h file also lets you home towards minimum or maximum. It is possible something like that is flipped.Quote:
Originally Posted by rhonal89
That's clough42 configuration.h ↑
Quote:
Originally Posted by Roxy
And this file I uploaded is the one from Marlin 1.0.2 the one I was using.
I pulled them into ExamDiff... There are differences that could do what you described. In one file there is:
#define INVERT_X_DIR false
#define INVERT_Y_DIR false
#define INVERT_Z_DIR true
In the other file you have:
#define INVERT_X_DIR true // for Mendel set to false, for Orca set to true
#define INVERT_Y_DIR false // for Mendel set to true, for Orca set to false
#define INVERT_Z_DIR true // for Mendel set to false, for Orca set to true
So... If I had to bet... I bet it was the X axis that crashed. Right? If you flip that value, it might just work. But I wouldn't do a Home operation first thing. I would connect to the printer in PronterFace and then tell it to move a little bit on each axis and see if reasonable things happen.
Yes, it was the X axis. Thanks I'll look into the value and change them.
Quote:
Originally Posted by Roxy
Update coming soon. I received lots of help from voodoo28.
Ok, Thanks to Voodoo28 for all his help am up and running. He shared his settings and everything seem to be working well for clough42 single extruder. Am still keeping and eye and see if nothing happens. Also I advice most people of the forum not to update to the latest marlin version as Roxy has advice it has problem or at least not the version I was using which was 1.0.2. Autobed level did not worked or register haft the time it like to skip G29 code. Also who knows what else is broken.
Update: April 28, 2015. Printed a six hour part and not one movement from the servo.