SoliForum - 3D Printing Community — Beginner Troubles

Re: Beginner Troubles

null@example.com (bpulst) — Fri, 23 Aug 2013 21:55:55 +0000

Ironman, and Bob, thanks for your insight.

Ian, I think your right, that could explain why the first 20 layers look ok then there are a couple "backlash spots" then it gets progressively worse. I'll attach a picture in the future so others can see.

Any idea what temp the stepper driver does this at? I have a IR temperature sensor to check.

Re: Beginner Troubles

null@example.com (IanJohnson) — Thu, 22 Aug 2013 20:42:44 +0000

Most likely the stepper driver is missing steps possibly because it is getting too hot. The chip protects itself by shutting down for a split second which can mean the z axis doesn't move far enough causing a squish and a shortened print. I used to have this problem all the time in a hot garage during the summer. Get a small table fan and blow it on the back of the printer and see if it helps. If it does you can look into a more permanent fan setup.

Re: Beginner Troubles

null@example.com (IronMan) — Thu, 22 Aug 2013 17:07:13 +0000

wardjr wrote:

Just a quick thought... there isn't a chance that your dealing with a slight power interruption? When I first got my printer the power supply wires on the output side would come loose as the solder would get to hot. Upon inspection the hole in the plastic case where the wire came out was pushing on it funny and when it would get warm it would loose connection. Not enough to really notice other than every now and then I would get funny movements out of an axis. Might be worth a look also might consider a fan on your control board those steppers get hot.

+1...I check my connections weekly!

Re: Beginner Troubles

null@example.com (wardjr) — Thu, 22 Aug 2013 17:04:13 +0000

Just a quick thought... there isn't a chance that your dealing with a slight power interruption? When I first got my printer the power supply wires on the output side would come loose as the solder would get to hot. Upon inspection the hole in the plastic case where the wire came out was pushing on it funny and when it would get warm it would loose connection. Not enough to really notice other than every now and then I would get funny movements out of an axis. Might be worth a look also might consider a fan on your control board those steppers get hot.

Re: Beginner Troubles

null@example.com (IronMan) — Thu, 22 Aug 2013 16:54:27 +0000

The 4000 to 3000+ ratio is roughly the same as your Model to Height difference...

Re: Beginner Troubles

null@example.com (IronMan) — Thu, 22 Aug 2013 16:49:23 +0000

Also, check this post...

http://www.soliforum.com/post/33418/#p33418

Re: Beginner Troubles

null@example.com (IronMan) — Thu, 22 Aug 2013 16:43:18 +0000

I think a .2" difference in height amounts to more than just calibrating extrusion thickness. You mentioned that the bed seems to skip when moving down to the finish position. When this happens, does the z-axis motor stop as well, or is it still running?

Is it possible you have lost a solid connection to the motor shaft? Check that connection.

Re: Beginner Troubles

null@example.com (bpulst) — Thu, 22 Aug 2013 16:36:56 +0000

Don't know if this is related to my height problem , but when a print is finished and the print bed moves down to the "finish Position" it seems to skip, stopping momentary then continuing on down. This doesn't occur when I move the platform up and down manually.

I'm using default setting minus the adjustment to the steps per mm.

Re: Beginner Troubles

null@example.com (bpulst) — Thu, 22 Aug 2013 16:26:51 +0000

Iron Man, so with default steps per mm , for a 1 inch cad height I had a accual print height of around .8 in.

I've adjusted steps per mm for the z to a little over 3000 to get height close, but there are still layers that are squished together.

I've ran a ran a die over the thread thinking there might be a bur on the rod that was binding the print some. That didn't help.

Bob, I appreciate it.

Re: Beginner Troubles

null@example.com (IronMan) — Thu, 22 Aug 2013 15:52:22 +0000

What is the height of your model (in CAD) versus the actual print height?

Re: Beginner Troubles

null@example.com (wardjr) — Thu, 22 Aug 2013 15:50:17 +0000

Basically what you need to do is all the calibrations you've read about in the WIKI. focus on Extruder calibration and then tell us about your set up... What software along with versions and what changes you've made to your printer if any. When did you get your printer and so on. I understand you had a stepper driver burn out and am guessing you have that fixed without complications other than Supports slow ship times.
I also sent you a PM and am happy to help out any way I can, especially for those of us that understand what snirt is
I went to college in Fargo and had a lot of friends up in Grand Forks.

Beginner Troubles

null@example.com (bpulst) — Thu, 22 Aug 2013 15:32:51 +0000

I hope you guys can help me a some.

So my X and Y axis seem to work just fine. Its the Z axis that is troubling me.

To clarify:
Backlash - is when you can see the extra wide lines that occur on the horizontal plane, but are viewed when looking along the z axis.

Under-extrusion -how would you define it??\

So here is my problem:

I'm having crazy amounts of "backlash" and my print are short.

I've adjusted the steps per mm to try to print kinda good prints and try to reduce the amount of backlash, at No help.

In my case I think the backlash is caused by the Print Bed not moving down enough. The Backlash isn't consistent enough to print a part with a accurate height.

advise??