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### Re: Problem X Axis

Posted: Thu Apr 26, 2012 12:23 pm
edwardrford wrote:
I've searched for a fly cutter with an 1/8" shank and have yet to locate one. If anyone were to run across such an (awesome) item, please post it in the 'useful links' section and please create a corresponding wiki entry.

-Edward
While not a fly cutter, might this work for a wood bed?

http://www.micromark.com/carbide-shapin ... ,8518.html

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 1:54 pm
I can't possible be sure, but it looks like the mandrel screw is a bit higher than the rest of the tool.

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 2:48 pm
Ok im not sure why this seems to be such a huge post on how to level. But...

When my Shapeoko arrives i intend to place it on a MDF and bolt it down to it.
Then simply use a normal level tool to level the whole thing out with some paper. (post-its work great!)

Also we arent sure if thats even the issue since nio hasnt replied.

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 4:39 pm
The only way to make your bed/spoilboard truly level to the machine, is to machine the bed flat with the spindle. No manner of leveling the board or shimming will make it flat to the machine.

All you need to do is write a simple gcode program to face the bed. Just draw a rectangle that is the size of work area (so measure your work area before attempting this or you will likely crash you machine) and pocket the bed down enough so that the entire area is cut (you probably won't need to cut more than 0.05" if you bed is fairly flat).

This will ensure that your bed is completely flat to the machine, which will let you get higher quality parts. You only need to do this once for each time you replace the bed, so make a program to do it for you, set the machine running, and let it do its work. That's the whole point of CNC! I'll post up my program once my Shapeoko is up and running.

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 6:03 pm
orcinus wrote:A bizarre idea - why not use a glass plate as a bed?
Probably not the best idea for 2 reasons:

1. There's no easy way to attach the work to a glass base.

2. "Crashing" the head takes on a whole new meaning.

Truthfully, glass is really hard (relative to most metals), so even accidentally, lightly etching the glass has a tendency to wear out bits. But a bad crash has the potential to shatter a glass base.

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 6:08 pm
AtomSoft wrote:Ok im not sure why this seems to be such a huge post on how to level.
[snip]
Atom,

Shimming the board with paper still won't handle twisting or bowing. Depending on what you plan to do with your Shapeoko it may be good enough for your purposes though. IIRC, people who were milling PCB needed pretty flat bases to get the job done well.

And the reason we mention this as the possible problem for Nio is that it's the most common cause of this type of problem. Unless his endplates are not milled exactly the same, his most likely problem is a warped base.

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 6:21 pm
Sandro is dead on. If the issue is bowing (or inconsistant thickness of material) then shimming till you are blue in the face won't make a difference.

Enraged hit the nail on the head: The only true way to get the bed 'level' relative to your X/Y is to mill it. That's standard protocal on this type of machine.

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 6:24 pm
Ill be sure to mill my MDF Flat then.... thanks guys... (i am what i am... a nooB )

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 7:34 pm
sandro wrote: Probably not the best idea for 2 reasons:
1. There's no easy way to attach the work to a glass base.
2. "Crashing" the head takes on a whole new meaning.
Truthfully, glass is really hard (relative to most metals), so even accidentally, lightly etching the glass has a tendency to wear out bits. But a bad crash has the potential to shatter a glass base.
Issue #2 is easily solved with a limit switch. You don't even have to hack the software to implement it - you can cut the enable pin on the pololu carrier (or stepstick) and wire a switch between it and Vdd.

Issue #3 depends on the application. If you're milling PCBs, you'll never want to go down all the way to the glass anyways. In fact, for most applications where Z-precision is required, you never really want to go straight through to the bed.

Issue #1 is the only "real" issue, at least in my opinion. I've got no solution for that one (hence the bizarreness of the idea). However, for "light" tasks with not that much lateral (tangential) forces, finding an appropriate kind of glue might do the trick. Something that has high strength in X and Y directions, but offers low resistance in the Z direction. A clamp of some sort might work too, although i must admit i can't figure out how it'd look/work from the top of my head.

### Re: Problem X Axis

Posted: Thu Apr 26, 2012 9:28 pm
Here's one Idea I stumbled on, I cannot take credit but give it a look seems like a workable idea
http://www.jcopro.net/2011/10/11/millin ... e-it-flat/
http://www.jcopro.net/2012/03/01/dramat ... flycutter/