<![CDATA[SoliForum - 3D Printing Community — Belt slop / backlash]]> https://www.soliforum.com/topic/10056/belt-slop-backlash/ Sun, 08 Mar 2015 03:52:26 +0000 PunBB <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/88800/#p88800 I used a printable tensioner, as mentioned above, though those tensioning springs are probably a better idea.

It helped a little.  Mostly I just decided I could live with the backlash in most situations.

]]> Sun, 08 Mar 2015 03:52:26 +0000 https://www.soliforum.com/post/88800/#p88800 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/88798/#p88798 Fredjikrang wrote:

Yeah, the left belt is easy to adjust the tension. I did that a couple of days ago.

Sorry to revive an older thread but my left belt tension (y?) is very sloppy how did you adjust the tension.  I cant see m to see anyway of doing this?

Thanks

]]> Sun, 08 Mar 2015 02:28:32 +0000 https://www.soliforum.com/post/88798/#p88798 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86245/#p86245 Timing belts are picky about tension. Too loose, and you will see backlash. Too tight, and you will also see backlash. There is a tension that is "just right", and the tensions of the left and right belt need to be equal. I believe the press drives the Y axis with a short motor belt below the back Y drive rod, and it needs to be tight. Your description indicates backlash on the Y axis, which is the most problematic axis on machines of this type.

An effective way to measure backlash is with a dial imdicator mounted directly on the X guide rods. That way you can put a number to it and eliminate some guesswork.

]]> Thu, 19 Feb 2015 22:36:01 +0000 https://www.soliforum.com/post/86245/#p86245 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86241/#p86241 There are no issues with the filament missing the layer... it just seems that the part is shorter in the Y axis.  I printed the Plus shape because I was wondering if the steps/mm were wrong... but the "arms" of the plus were exactly 10mm wide, while the overall length was still about .5mm short.

It's very repeatable... I don't have any wavyness or anything in walls.  Just not sure what I need to adjust.  when I move the pulley by hand now I don't see the sloppiness in the belts... It seems odd that tightening them didn't change the amount of backlash at all though.

]]> Thu, 19 Feb 2015 22:21:14 +0000 https://www.soliforum.com/post/86241/#p86241 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86135/#p86135 Not OCD... .5mm is the difference between the filament being laid on top of the previous layer and it being totally off.

]]> Thu, 19 Feb 2015 08:40:04 +0000 https://www.soliforum.com/post/86135/#p86135 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86121/#p86121 I give up for now.... The belt tensioners make things look great... but I still have cubes that are .4 mm shorter in the Y axis.  I guess there is some other factor causing backlash.

If I print a part that has Y-direction measurements that are mid-stream (such as a Plus shape), the dimensions are accurate, but a cube or circle results in the Y-direction being .4 - .5 mm shorter than the X-axis.

half a millimeter probably doesn't matter for the stuff I'm likely to print... it just bothers me. (OCD?)

]]> Thu, 19 Feb 2015 06:53:43 +0000 https://www.soliforum.com/post/86121/#p86121 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86099/#p86099 Fredjikrang wrote:

Yeah, the left belt is easy to adjust the tension. I did that a couple of days ago. The right belt on mine isn't too bad, so I haven't touched it yet. I might try one of those printable tensioners though. My big problem in my X belt. It is really loose! And I haven't found a good way to adjust the tension on it yet.

I wonder if taking the screws off the bottom of where the x belt passes through (I think there are 4 screws there) will reveal a similar mechanism as the y belt tensioners.  Mine is WAY too tight to the point where the x-axis makes a terrible noise and I can see the belt wearing already after only a dozen or so prints.

]]> Thu, 19 Feb 2015 03:23:21 +0000 https://www.soliforum.com/post/86099/#p86099 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86094/#p86094 Yeah, the left belt is easy to adjust the tension. I did that a couple of days ago. The right belt on mine isn't too bad, so I haven't touched it yet. I might try one of those printable tensioners though. My big problem in my X belt. It is really loose! And I haven't found a good way to adjust the tension on it yet.

]]> Thu, 19 Feb 2015 03:11:18 +0000 https://www.soliforum.com/post/86094/#p86094 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86091/#p86091 How about providing some high quality pictures? I bet we can figure it out.

]]> Thu, 19 Feb 2015 03:03:52 +0000 https://www.soliforum.com/post/86091/#p86091 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86089/#p86089 closed loop.  I can see where they adjusted the tension on the left side... they just didn't make it tight enough.

the left side is actually worse... I think they just didn't adjust it properly... the right side isn't *as* bad, but as I said, it seems like there is very little room for adjustment there.  I think they are relying on the tolerances of the molded parts... but I'm new to this, so there may be something I'm missing.

I did ask solidoodle for a procedure to adjust the tension... the case is still "open".

]]> Thu, 19 Feb 2015 02:59:27 +0000 https://www.soliforum.com/post/86089/#p86089 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86088/#p86088 Are the belts open loop or closed loop (cut or not cut)? If they are cut, it sounds like the right side was cut too long. Just a guess.

]]> Thu, 19 Feb 2015 02:55:42 +0000 https://www.soliforum.com/post/86088/#p86088 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86087/#p86087 android78,

Yes, that is the design.... at least on the left side.  On the right, the two tabs are so close together, there really isn't room to leave any excess belt.  The bigger problem is that those clips are injection-molded and very thin...  I'm pretty sure a hair too much pressure would break them (based on my experience with a few other pieces on the press.).

What I've done for now is print a small tensioner and placed it directly next to the carriage.  I then reduced the Y-axis size in Repetier to be 190mm, to prevent it from hitting the pulley.  That seems to have worked, from visually inspecting the situation.  I'm going to try some test prints shortly.

]]> Thu, 19 Feb 2015 02:53:18 +0000 https://www.soliforum.com/post/86087/#p86087 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86086/#p86086 I think the belts on the y-axis have a section (in the y-carriage) that holds two points of the belt.  You should be able to slip the belt out of the holder at one end of the holder and pull the belt so that it catches a tooth further along, making a slack part between the two sections of the belt.  I don't think you should be needing to put a tensioner in there unless you need really fine adjustment (less then one tooth difference in belt length).

]]> Thu, 19 Feb 2015 02:45:24 +0000 https://www.soliforum.com/post/86086/#p86086 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86085/#p86085 There has to be a way to adjust the tension. How could they ensure equal tension otherwise? From my experience if the belts are taught enough you can't install them . . .

]]> Thu, 19 Feb 2015 02:37:51 +0000 https://www.soliforum.com/post/86085/#p86085 <![CDATA[Re: Belt slop / backlash]]> https://www.soliforum.com/post/86081/#p86081 Argh.  Solidoodle has the belts in a plastic "channel" and it's not possible (or at least not very easy) to get to the alternate side of the belt to put a tensioner on (so that it won't interfere with the pulleys).  I'm going to see if I can squeeze one in there, but I'm doubtful. 

I may have to dissassemble far enough to remove a pulley... didn't really want to do that... I'm worried about getting things out of alignment.

]]> Thu, 19 Feb 2015 02:15:47 +0000 https://www.soliforum.com/post/86081/#p86081