Thursday, November 28, 2013

Cube Print Table Tool - Checks and Helps Level the Cube Print Table

I have spent much of my free time in the last three or four months trying to come up with a tool that would help Cube owners check the level status of their print table and make the leveling process a lot easier and more accurate.  There have been a lot of ideas and failed attempts along the way.

But, the effort has finally born fruit in the form of a tool that Cube owners can print from an STL file on the Cubify Store site.  I will be putting up the files as soon as I have a video completed that demonstrates how to assemble it and use it.

It works by hanging a bracket off of the print head cover.  The bracket positions a pivoting pointer near the center of the print jet.  The pivoting point rides along the print table and indicates the relative difference from the print jet at the four corners of the leveling process.

Cube Leveling Tool - Split view

Here is a split view of the componenets of the system...

Cube Leveling Tool - Split View

The silver component is the primary bracket that attaches to the print head cover.  The cyan component is the pivoting pointer that actually shows the relative offset of all the four corners of the print table.  And, the magenta component in the above image is the clip that securely holds the primary bracket in place.

Cube Leveling Tool - 3D View

Cube Leveling Tool - 3D View

The best way to see how the components work together is by seeing them in this 3D view from Moment of Inspiration.  As can be seen, there are raised rails inside the primary bracket that fit into the first and last slots of the print head cover.  This precisely aligns the tool so that the bracket has no play as the tools is being used.  To lock the bracket securely into place, a clip, shown in magenta is slide down over the head cover and bracket and is seated by ears on the bracket to make sure that it is in the proper, most secure place.  A a rail on the clip locks it into place in one of the slots on the head cover.

The bracket includes a shaft for mounting the pivoting pointer and also includes a pointed extension with which to gauge the movement of the pivoting pointer. 

Cube Leveling Tool -Front view

The pointed extension is best seen in the front view.  It is purposely designed a bit long to accommodate differences in how the pivot pointer might be attached.  Simply clip off the end for a flush match.  When starting the leveling process, the top of the pivot pointer is lined up with the top of the extension by raising and lowering the print table giving us a basleine of comparison for the other 3 corners.

Cube Leveling Tool - 3D View

Cube Leveling Tool - Left view

The STL files include two different pivot pointers.  One is mounted directly using a 4mm bolt.  The other permits the use of 3x4x10mm or 4x4x10mm bearings for much smoother action.  The bearings are inexpensive fishing reel bearing that can be purchased on the internet.  The source I use is VBX Bearing and I buy 10 at a time for under $20.     While either 3mm or 4mm inside diameter will work, it is easier to find the 4mm nuts, bolts and washer in local hardware stores.  This image portrays the bold-only version.

Cube Leveling Tool - Left View

You will notice in the above image that the sliding portion of the pivot tool has a peculiar shape. There are two special features of this shape.  The first is that it is elongated so that it will not fold under as it is moved forward across the print table.  The second is that the elongated portion is lightly raised so that it will not interfere with the actual measurement when the movement stops.

NOTE:  Multiple coats of fingernail polish applied to the bottom contact of the pivot tool go a long way to making the movement silky smooth.  I have found that Sally Hanson Triple Shine Top Coat, that can be found at Target, works very, very well.

You will notice that there is about a 5 to one ratio between the bolt hole to the pivot point contact and the bolt hole to the end of the pivot point.  It is this difference that makes it so easy to level the print table more accurately.  Each .25mm difference translates to about 1.25mm swing at the end of the pointer.  And. 1.25mm is a LOT easier to see than .25mm.

A Note About the Price

I try to keep most of the things I have uploaded to the Cubify Store at the minimum allowable cost.  But, this time I will list the tool at $10.  The price reflects the extension hours of design and testing that went into the design along with the realization that it is going to be an enormous time saver for Cube owners.  Moreover, I want to be able to design other useful things to make life easier for Cube and Sense owners.  Having the funds to do so is very helpful. 

I also want to be able to design a version that is specifically designed for printing on the SLA printers and I expect revisions to be a bit on the expensive side.    So, I hope you understand why the cost is being set higher than my normal price goals..

Quick & Dirty Demo Video

I plan to create a much better video that not only covers the information in this one; but, how to go through the entire leveling process using the tool.  I not only use it to level the print bed.  I sue it to check the level of the print bed after carrying it around, etc.  As a result, I am getting much better adhesion. 

Sorry for the poor sound.  I shot this in the outside studio just using the camera's microphone and the sound of the printer cut the autolevel back.



WARNING!!!

Be sure that you start the leveling process and then lower the table BEFORE attaching the tool.

As soon as I have uploaded the STL files and/or created the new video I will update the status. 

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