1 (edited by nathankau 2012-12-07 00:54:15)

Topic: Random set screw lying around (also power supply help)

I just received my Solidoodle in the mail!!! Yay!!!

I found a tiny 3mm long set screw on the bottom of the printer. Any ideas where it goes?

Also, the power supply came unplugged. I checked the sanguinololu wiring schematic and ground is on the bottom. Correct? I plugged it in with the ground on the bottom for a few seconds before I realized the power supply didn't have an on/off switch. I hope I didn't fry the sanguinolulu.

EDIT: I checked the pulleys sprockets and they the driving ones have their set screws.

2

Re: Random set screw lying around (also power supply help)

what is its length?

3

Re: Random set screw lying around (also power supply help)

The set screw is 3.1mm in length, 2.9mm in diameter, and the hex hole is 1.5mm wide.

4 (edited by nathankau 2012-12-07 01:21:26)

Re: Random set screw lying around (also power supply help)

Crap. Well I think I fried the sanguinololu. I was using the wrong diagram which had a different orientation of the screw connector. The ground is NOT supposed to go on the bottom. I probably fried the pololus and the 5v reg.

EDIT: The blinking green on the power supply and no response from the motors gave it away.

EDIT: Well it's not fried. I swapped polarity and now it seems to be working.

5

Re: Random set screw lying around (also power supply help)

I think the diode may prevent frying the board with backwards polarity.  Did you find out what the set screw was from?  If it fell out of one of your pulleys, it will definitely come back to bite you.

6 (edited by nathankau 2012-12-07 02:40:02)

Re: Random set screw lying around (also power supply help)

Still haven't found the correct place for the screw. When the x-carriage travels away from the back of the solidoodle it makes a loud noise. It sounds pretty harsh. I can't really tell, but it might be coming from the right side of the x-carriage (the side without bearings).

EDIT: That diode saved me!

7

Re: Random set screw lying around (also power supply help)

If the set screw is not holding the pulleys in place, there will be a little play between the left and right sliders.   When this happens, one side can move a little without the other and it causes a huge amount of friction and eventually won't travel at all. It sounds like it has to be from your pulley in the very front right or left or very back right or left.  One of these would cause this sound when it is moving in the y direction ( forwards and backwards when looking at the front door ).  It would be a good time to check that your belt tensions are equal as well.  If you find where it goes, be careful not to strip the set screw since they are easy to strip and you be in a mess if they are stuck in the pulleys part way.

8

Re: Random set screw lying around (also power supply help)

That's exactly what's happening. The bearing side of the carriage can move a few millimeters independent of the other side.

9

Re: Random set screw lying around (also power supply help)

Same thing happened to me... My set screw actually stripped its way out and I had to replace it.... The very back left pulley is where it came from....
http://farm9.staticflickr.com/8061/8250683031_9b5c4380c4_b.jpg

10

Re: Random set screw lying around (also power supply help)

The back left screw came loose for me too. I tightened it back up and now the carriage moves great.

I have another problem though. The print head seems to drag across the layers. For infill small ridges appear. Is this happening because the head is to close? I've also noticed inside and outside dimensions are off by about .15mm. Is this caused by the layer squishing and dragging or something else? Thanks.

11

Re: Random set screw lying around (also power supply help)

The flow rate is too high.  The threads bump into each other which squishes the plastic up into ridges.  Are the dimensions to high or low?  Too wide can be from too much flow.  To short could be from shrinkage.

12 (edited by nathankau 2012-12-09 00:46:18)

Re: Random set screw lying around (also power supply help)

Thanks ian. To change the flow rate do I change the extrusion multiplier?

The outside dimensions were .15mm too big and the inner ones were 1.5mm too small so it's a flow rate issue.

13

Re: Random set screw lying around (also power supply help)

Ian, I found your blog post explain flow rate. I'll update once I print the hollow cube.

14

Re: Random set screw lying around (also power supply help)

I got the single wall to be +- .01 mm of .42, but my extrusion multiplier is 0.6 (1.75mm diameter filament). I feel like something must be wrong for my multiplier to be so low. I remeasured my filament and its just about 1.75mm.

15

Re: Random set screw lying around (also power supply help)

you need to calibrate your extruder so you can set the right amount of 'extruder/motor steps per mm'

basically the machine is pulling in to much plastic

check ians blog, he has a great article on it.

once you do that you will notice your muliplier will go back up to .9 to 1.1