SD4 problems

Thanks for your answer.

I think I may have 2 problems right now.

1. The X and Y belts are loose. I don't get perfect circles. I see bumps and they are uneven. I have aligned the Y belts, but I think I need to adjust the tensions as well.

2. The amount of plastic coming out of the extruder is not enough. The extruder multiplier was set to .6 and to test I increased the number to .8 and now I do see much more plastic coming out and the solid walls are filled. But I think .8 is to much so I did measure how much was extruded when extruding 100mm. 136mm was extruded so with some calculation the extruder multiplier should be around 0.73. I didn't have the time to try that setting last night, but I will do it tonight.

To answer your questions on the adjustments I have done so far:

* Y-axis belt tension
- I have only aligned the belts, I will check the tension tonight.

* Leveled the bed and adjusted z-stop height (looks ok from the photos)
- I have leveled the bed with a piece of paper as instructed and I think the Z stop height is good.

* Extruder steps-per-mm
- I need to adjust this one as I described in bullet point 2 above. I hope this is the faulty parameter for the walls not being filled.

* Wall thickness with a test cube
- This I haven't done yet, will try it.

Thanks again for the tips, I'll report back when I have performed the adjustments suggested.

Further information: Solidoodle's version of Repetier Host does not ship with the correct nozzle settings. You have a 0.4 nozzle and should be extruding at 0.48; you'll find your extrusion width under advanced settings in slic3r. Solidoodle sets it up by default to 0.42 and attempts to make up for this with a low extrusion multiplier. It does not work well. When you do your calibration cubes, use an extrusion width of 0.48, not 0.42. You will notice a dramatic improvement.

Edit: Oh, IronMan beat me to it! Still, this is something SD does that greatly handicaps new users in getting successful prints so it's worth re-iteration.

Thanks for all good replies.

I have done some adjustment and I do see improvements, but I'm not satisfied yet.

The Y belts were loose so I have tighten them and aligned them again.
I also calibrated the extruder, it was extruding 136mm instead of 100mm so I modified the extruder steps per mm setting in the EEPROM so that's fine now.

The flow rate was also adjusted slightly. Thanks for the .48 tip, I had no idea about that.

But still the circles are still not round and I'm getting "holes" in the prints.
I have attached a picture. I think my problem with the roundness has to do with the X axis as I see issues at 9 and 3, is that correct? The X belt is tight, are there any further adjustments that can be made?

Hi

I printed the circle stl, it's attached.

Thanks
Peter

Ok Thanks for looking. I will head over to the thread suggested and post my print there as well.

Any ideas on why the prints are not solid when they should? You think that is caused by the same thing that makes the circles uneven?

Your extrusion has improved a lot!

Judging from that circle test, it looks to me like there's a fair bit of backlash in the y axis (see how it's misaligned front-back at the start of the circle?), this is likely at least partly the cause of the gaps in the previous prints.

If you've tensioned and balanced the y-belts, have you also considered the tension of the small drivebelt on the y axis driveshaft? You can adjust the tension a little on this one by loosening the 4 bolts holding the y motor to the case, pushing the motor down, and re-tightening the bolts.

Also, have a read through these two threads, there may be some inspiration there:
http://www.soliforum.com/topic/4824/how … -for-ever/
http://www.soliforum.com/topic/8357/y-s … belt-slop/

Who knows, maybe you'll get lucky. Solidoodle has changes some things on Solidoodle 4 over time.

If not, try to get 3 6x13x5 flanged bearings and replace the 3 bushings on the back Y rod with them. Should just come off if you push and then you could push the bearings in their place then.
Something similar to what the first thread grob linked to suggests to try. As Solidoodle 4 users we already have the holder for the bearing/bushing so no need toprint one I think.

Mine haven't been shipped to me yet to test.
I'm sorry to tell you none of us know what the issue is and what will solve the issue just yet. We're currently replacing parts which others have said works for them until we find what which one works for us Solidoodle 4 owners.

Like I said I haven't tried this myself yet and don't know if it'll work, but talking to jagowilson and wardjr about this I think I have a decent idea of why it is helpful.

The point is not to just replace the two bushings on each side of the frame to lessen the friction on the rod.
You'll also replace the pillow block bushing found in Solidoodle 4's with a bearing, and for Solidoodle 3 add one (or two) like pirvan has done on his machine.

The pillow block which was added in Solidoodle 4 I think was to reduce the bending of the back 6mm rod caused by the motor belts and the side Y belts pulling it. But since Solidoodle decided to use a bushing instead of a bearing the pillow I think does more harm than good by introducing more friction, even if reducing the rod bending, because that bushing is closer to the origin of the bend and so more friction is created.

In short we want to decrease friction and rod bending (which also results in friction...) at the same time and see how it goes.
When well reduce friction, we can make the Y rod tighter and get rid of any remaining backlash without causing the motor to skip steps.
Unless friction can affect stepper motors in any other way except step skipping (which we don't have), I don't think this will help by itself, without tightening the belt some more.

Pirvan also had two pillow bearings in his Solidoodle 3 before he made the y motor tensioner mod. It's possible that also played a role for his success.