LaserCutFrame

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Revision as of 12:17, 12 July 2011 by Smurf (talk | contribs) (Install Z axis Pieces)
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Image of a Huxley Frame, assembled from a TechZoneCommunications Huxley Kit

General

This page and its peers should guide you through assembling a RepRap Lasercut Mendel from the TechZone kit, or from parts you have lasercut which are the same as the TechZone parts. It is a work in progress, and needs some help, feel free to edit this document to add comments of you your own, or contact us [here] and send us messages asking us for better clarification or details.

I am starting by posting the pictures I have, and over the next few days, I will fill in the instructions and detials (6 April 2011)

Thanks,
Lambert (TechZone R&D/Support/Documenter)


You can access this page and it's peers (for the other parts of the Lasercut Mendel assembly from the TechZone Lasercut Mendel Page



We Assemble the Frame as Units, the Top Unit, the Front Unit and the Back Unit, then we put them together. To begin with, we assemble parts just finger tight, and into aproximate areas. When it is all together, we will fix things by measurements, and tighten them up.



Top Unit

Photo of the parts used in the top unit
Photo of an assembled top unit
On the left is a picture of the parts used to make the top unit:

Simply thread the inside nuts onto the bars, then washers, followed by the top vertice pieces, more washers and the outside nuts.

Make the parts just finger tight for now, we will get the exact placement and tighten it up a little more at a later time.

It should look something like the photo on the right when you are done assembling this.


Front and Back Unit

Photo of the parts used in the Front unit
Photo of an assembled Front unit
The parts Used to make the Front unit are pictured on the Left, and an assembled front unit is shown on the right. The parts used are:
Photo of the parts used in the Back unit
Photo of the parts used in the Back unit

Front Unit

    • (2) Vertices
    • (1) Y Idler
    • (2) Y Smooth Bar Clamps - printed parts
    • (2) threaded rods, two of the four shortest rods
    • (16) 8mm Nuts
    • (16) 8mm washers


Back Unit

    • (2) Vertices
    • (1) Y Motor Mount
    • (2) Y Smooth Bar Clamps - printed parts
    • (2) threaded rods, the other two of the four shortest rods
    • (16) 8mm Nuts
    • (16) 8mm Washers



Idler and Motor Bearings

    • (4) 4mm X 40mm bolts
    • (8) 4mm Fender Washers
    • (12) 4mm Washers
    • (4) 4mm Nylock Nuts
    • (4) Bearings



Put the idler unit on first
It is easiest to attach the bearings if you do them before you assemble the units. There are two smaller holes for the bearings on the idler and on the motor mount. The motor mount also has a small hole on the point that is for mounting the opto end stop. If you have the idler on the left with the point pointing to the left and the motor mount on the right with the motor portion pointing to the right the bearings should be on the side that is facing you. The bearings go together by first putting a washer on the bolt. Then put the bolt through the hole. Then put on a fender washer, a regular washer, the bearing, another regular washer, another fender washer, and then the nylock nut.


Once you have the bearings attached you can put together the front and back units. Start with the idler unit. First slide the idler to the center of the bars and put washers against it on each side and then tighten the nuts down (finger tight for now, we will tighten it the rest of the way while we are doing the squaring later). Next put on the nuts for the inside of the smooth bar clamps on the top bar (the top bar is the one closest to the point on the Y idler) followed by washers. Then slide on the smooth bar clamps and the washers and screw on the nuts. Now put on the nuts and then the washers for the vertice pieces on all 4 bars. The vertice pieces go on so that when it is sitting on the point near the bottom bar the top of the vertice is pointing towards the outside (same direction as the point on the idler). Once you have the vertice pieces in place slide on the washers and finger tighten the nuts. The back unit goes together the same using the motor mount in place of the Y idler in the above instructions. The part the motor mounts on goes to the outside and the top is closest to the small point for mounting the opto end stop.


Install Z axis Pieces

Photo of the parts used when assembling the frame
Photo of an assembled Frame

The parts shown on the left are used to put the bottom of the frame the rest of the way together,

The parts Are: From Above

    • Top Unit
    • Front Unit
    • Back Unit

Additional Parts

    • (1) Z Axis Combo unit
    • (1) Z Axis Driven unit
    • (6) 8mm Threaded rod to connect the vertices,
    • (1) 8mm Threaded rod for the Z unit.
    • (32) 8mm nuts
    • (32) 8mm washers

Putting together all the pieces of the frame this way is easiest if you leave some space for all the printed parts to move a little. This way, if they aren't perfectly straight, they can be easily shifted into alignment. Leave them loose until the frame is fully assembled, then start tightening it down. Leave it finger-tight for now, as you'll still need to follow the procedure for squaring the frame. You should be able to follow the instructions on the Mendel squaring axes page with only slight changes to accommodate the size of Huxley.


Photo of the Z Units of the frame
Start by putting the Z unit together as shown.

NOTE: You may find it more convenient to install both Z bearings into the corresponding Z Motor and Z Idler printed parts, before doing anything else with the parts. To fix the bearings, put short bolts (with washers on both sides) into the 3 small holes surrounding each of them.

Photo of the bottom portion of the frame
Then put two of the vertice bars through the Z unit and add the Back unit and the front Unit, to make the Base, you will probably have to adjust several of the nuts as you assemble this, to get things to go together.

Last, use the four remaining vertice bars to install the top unit to the Base. You should end up with a frame that looks like the picture at the top of this page!


At this point I like to install the Y axis before attaching the top of the frame.

Squaring, and Truing the Size/Shape

To adjust the frame you simply make lots of measurements and adjust the nuts until all the bars line up where they should be. You can do this as the frame now, and then adjust the Y axis after it is installed, but I like to do them all at once, so I wait until the Y axis is installed then make these adjustments (click here for Y axis instructions). This is much easier to do if you have the machine on a flat surface. I know this from experience, there was a machine I was building, and I built it on top of all the clutter and tools which had accumulated on my work space... I spent WAY too much time trying to get all the measurements to work.

pieces to attach the frame top piece
frame top piece attached
The front, top and back units are all adjusted to have the same width, as measured on the threaded rod that forms the triangles. I set my bars to 175mm apart, you can use a different number and that is OK, if you go too narrow then the build plate won't fit and if you go too wide the bars won't be long enough. I measure it from center to center on these rods near the vertices. Each unit should be measured near both of the rods that make up that unit. As you adjust the front and back unit, you may need to loosen or tighten the Z bar that is parallel to them in the bottom. I don't ever measure this Z bar, but rather when I have both the front and back units adjusted, I simply snug the nuts for this bar as well (and threadlock it).



The top unit is a little different from the front and back units, because I want to leave the excess rod hanging out the ends such that it is equal on both sides (or nearly so). The space in between still needs to be the same as for the front and back units.



I then measure from center to center on the threaded rod that makes up the units to adjust the distance for the triangle threaded rods. They are all the same distance, making equilateral triangles (I was told that geometry would come in handy some day...) I set mine to 215mm again, you can set yours a little different from this, but if you go too far it will affect your available print height.



Now I want to make sure that the Z Axis is perpendicular to the Y axis. To do this we measure from both vertices to a point on the centerline of the Z Axis, adjust until they are the same measurement (it is not real important that they be a specific measurement, only that they be the SAME as each other.

After all the adjustments are made on the Frame, I like to put threadlock on, so that the future vibrations won't cause any shifting of the nuts.


Now I adjust the Y axis.

I simply measure the bar that has the 360 side of the Y axis and make sure it is parallel to the the frame piece. I do this by placing the clamp on both ends ofthe Y axis the same distance from the Frame Vertices.

Then I adjust the 180 side so that it fits freely in the 180 bearings for the entire travel of the Y axis. Sometimes, the second bar is not perfectly parallel to the first - this is OK and it is a result of any imperfections in the printed parts in the Y axis. The important thing is to remember that the whole axis will travel the path of the 360 bar, and the 180 bar will keep it from falling, or bumping upwards.

Any nuts or bolts on the Huxley - as it is assembled so far - should now be tightened and threadlock applied if appropriate. (ie, you don't need threadlock on any nylocs, or on the nuts which are embedded in plastic parts)

The Y Motor Mount and the Y Idler are adjusted and threadlocked into place as you install the Y belt.