First cut

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Re: First cut

Post by WillAdams » Sat Jun 25, 2016 10:18 am

Please also check your belt tension, esp. on the Z-axis.


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Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets

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Re: First cut

Post by JeromyReno » Tue Jun 28, 2016 10:55 pm

what are your feeds and speeds. it looks like you are trying to cut to much at one time and it's forcing the z plate to bend, it's like the weakest link on the machine. all of those passes are at 100% step over so it's putting a lot of load on the cutter. for a surfacing pass you would probably not want to use the whole cutter like that, try 30% or 40%. same goes for the plunge cutting, if you are useing a 1/4 bit and going 1/8' deep that is a lot of would to cut in a single pass, at least on a s3 it is.

so 1000mm a minute is just about 40 imp. i run 40 ipm with .125 depth of cut and 40% cut width. so with 100% cut width you are at more than twice the chip load.

so plunge slow because the surface area of the bottom of the cutter is very large. ( around 1/3 of the feed you are cutting x y with. router bits are not made for drilling.)

run a lower feed when using the whole bit to cut. (try not to use more than 50% of the cutters width.)

and the deeper the cut you are taking at one time the slower you will have to run the x y feed.

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Re: First cut

Post by schafe94 » Wed Jun 29, 2016 3:17 am

Just to rule out other problems, run the same program that you ran before from your pictures, but this time with feed rates of 10% of the other tests.
If your surface cuts become smooth and flat, you know you were just cutting too fast before.
If it is still has steps like before, you likely do not have the router bit plumb.
Either your Z axis is slightly out of square from the x axis, or the router is not sitting properly in the mount.
I had the same problem when I first set up my SO3 and I needed to slow things down and make sure I was using sharp bits.
Good luck.

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Re: First cut

Post by cobalt60 » Fri Jul 01, 2016 11:52 pm

If you posted the file itself, perhaps someone could run it on their machine, just to 100% confirm your instructions aren't weird.

I'd also add: Are you VERY sure your bit is tight? You mentioned in your first post that you had a bit tightening problem, which honestly should never actually be the case (just crank down on tightness) - any more detail on that?

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