When I put a large square against the Gantry it’s out of plumb about .078 which is about a strong 1/6" which is throwing my tramming out on the Y axis. I trammed the X axis and its good after some adjustment. How do you tram the Gantry or tilt it about 1/16" I need to tilt the top of Gantry towards the rear or the Y axis? Spoil board has been surfaced and the table 5 pro is sitting on is level.
I use shims in between the Z plate and X axis gantry to shim it in tilt.
Thanks for the info Josh. I’m watching a video as I text on how to do this.
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There is a difference in definition between the words plumb and level.
To my reading, you are suggesting that your “Gantry” is not leveled from front to back.
the rear of the gantry aprons 6" sold face of black anodized aluminum it needs to rotate about 1/16" or a smidge more towards the rear. hence the out of plumb.
It is a minor semantics difference, but plumb refers to a relation with gravity. Level means in respect to 2 different surfaces. In this case level is the proper word as you only care about the relation to the machine, not gravity. Minor difference, but level will be more widely understood in CNC terms.
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Not to (but I just did) jump in, but aren’t level and plumb two sides of the same coin? They are both relative to local gravity (plumb bob, level bubble). In my experience the term is “tram” as in tramming the axes. Slant-bed lathe can be in perfect tram with the X axis 60° from vertical…
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I will note that I find it best to work from large → small, so start with the table, and level it — I use a Starrett level.
Not in equipment terms. In equipment terms a leveled wasteboard is one that is parallel to the X and Y axis. So your wasteboard could be at a 22.650° tilt to gravity, but be level in respect to the axis. In carpendry terms your right in that it’s spirit and gravity based.
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I get what you’re saying, Josh. The X and Y axes, as long as the Y axis rails are parallel to each other, determine a plane (whether X is orthogonal to Y or skewed into a parallelogram they still mathematically determine a plane) and the wasteboard will be surfaced to a constant offset (“level”) to that plane. Then the Z axis needs to be orthogonal to that plane. If the Y axis rails are not parallel to each other, they will produce a twist to the X-Y “plane” but the wasteboard can still be surfaced to a constant offset from that “plane”. (You’ll get wonky parts but they will be internally self-consistent…) I’ve never owned an SO–my moving-gantry days were spent with a Techno-Isel machine a couple decades ago.
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I’m going to ignore the semantics conversation.
1/16” mis alignment in the brackets to the x axis gantry tube seems extreme to me on a 5 pro.
Are you sure you have the gantry secured in the motion system properly?
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David, what did you register the base of your square on? The already-faced spoilboard? Did you check the face of the Z plate or the faces of the X profile rails themselves? If the gantry is square to the base, those rails will be in the same plane (i.e. both touching the blade of the square resting on the spoilboard). Then you can check whether the Z rails are parallel to the plane formed by the faces of the X profile rails (i.e. vs. the bottom and top X rail), and whether the face of the Z plate is parallel to the Z rails, and go from there. (That is kind of following on what Will said, I realize…)
I seem to remember an anecdote on this forum about a flat washer that got placed in the wrong sequence in a stack of components…
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Order of what I did.
- I discovered by machine needs tramming after surfacing the spoil board and had scoops or scallops in mdf.
- Put a SST tramming device with two calipers on spindle. I trammed the Z axis in the X plane. Its perfect. I loosened up the spindle holder and tilted a few times Looks good
- Checked the Y Axis tram and its out a lot. Put a square up against the vertical/ back side of the gantry and it’s out a strong 1/16" Put some metal shims under one side of the gantry where it mounts to the side brackets. It’s still out a lot.
- Back side 0f gantry is now perpendicular to the spoil board. It’s still out quite a bit. Looks like a1/16" on the double caliper SST Tramming device
First I would stop using the back of the gantry I would be using the flats of the linear rails on the front. That’s what matters
Second. Make sure you are using that tramming gauge on a piece of glass or other calibrated flat surface.
The back of the Gantry should be parallel with the front of the gantry which the linear rails are mounted to. @ quicky06 What you’re stating doesn’t make any sense. Am I missing something?
There is a step you skipped. You need a leveled surface to tram on. My aporoach is to bolt down a piece of MDF and surface it with a 1/4" endmill with a small stepover. That makes a surfaced area to then tram on. If you don’t do that, or shim a plate level, your tram will not be accurate.
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Josh I’ll do that next. Thanks
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The gantry is an extrusion. The surface the linear rails mounts to is machined flat. The rear of the extrusion is no guarantee to be parallel with the machined surface. It’s meaningless if it is. What matters is the linear rails. Measure off the rails.
The proper way to tram is to resurface wasteboard. Put a known flat surface down. Then tram. Then resurface again. Without the known flat you could be measuring cupps caused by the tramming issue. Glass is a simple way to do this.
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I’ve done this many times and many ways in almost a decade of Shapeoko ownership and 8 Carbide 3D machines. In my opinion people WAYYYYYYY overthink this. With a relatively small diameter endmill and low stepover on a surface, cusps are minimal. Like a few ten-thou minimal. I’ve seen much more variation in the glass most people use in an overly complex method.
Either gets you there, especially in the tolerances we’re machining to. One is just faster, cheaper, and well finer what most of us have for metrology.
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I bought a cheap set of feeler gauges from the auto parts store and use the individual pieces to get as close a s I can. Mine was .022” out.
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