Squareness and Calibration of Joe's 2006

[PhillyCyberJoe]

robertmonroe,
I just put the pulleys on the gantry because it was convenient while I had everything apart. I also reinforced them with a piece of maple inside the lower torsion box for added strength. I haven't actually re-installed the cabling at this point, as the gantry seems much better with my previous adjustments.

There is a great thread at Make your Gantry rock solid!

Others have installed the sliding knot onto the Joe's 2006. Maybe they will respond with their opinion.

Joe

[jdell42]

Is the sliding knot gantry stabilizer worth adding on?

I added the sliding knot to my 06 Joe and found little differnence. I did this not to correct an x/y squareness problem but to help stabilize the gantry a bit. I run my router at 150 - 200 ipm and rapid changes in the X direction would affect the z height ever so slightly and having the "critical eye" that has been mentioned I attempted to fix it.

If I push on the Gantry in the X direction I can measure a bit of deflection. I have determined its a limitation of the machine design / materials vs. anything I can tweak. I have learned to live with it and will probably just make a stronger machine for my third one.

[BobF]

I added the sliding knot to my 06 Joe and found little differnence. I did this not to correct an x/y squareness problem but to help stabilize the gantry a bit. I run my router at 150 - 200 ipm and rapid changes in the X direction would affect the z height ever so slightly and having the "critical eye" that has been mentioned I attempted to fix it.

If I push on the Gantry in the X direction I can measure a bit of deflection. I have determined its a limitation of the machine design / materials vs. anything I can tweak. I have learned to live with it and will probably just make a stronger machine for my third one.

jdell42,
I can push on mine and measure some deflection with a dial indicator.
How much is "a bit of deflection"? If you can measure it with a ruler, your bearings may not be tight enough. If you can measure with a dial indicator, its the same as most.
I cut at 100 ipm and rapid at 200. I have not measured z height changes with a caliper, but I don't see any during cutting. I have cut out parts with pretty tight tolerance on Z and been happy. Example, I cut a piece of acrylic for the corner finder and the tolerance of the cut is nearly immeasurable. The finished height of the copper pipe is dead on all around.

[jdell42]

jdell42,
I can push on mine and measure some deflection with a dial indicator.
How much is "a bit of deflection"? If you can measure it with a ruler, your bearings may not be tight enough. If you can measure with a dial indicator, its the same as most.
I cut at 100 ipm and rapid at 200. I have not measured z height changes with a caliper, but I don't see any during cutting. I have cut out parts with pretty tight tolerance on Z and been happy. Example, I cut a piece of acrylic for the corner finder and the tolerance of the cut is nearly immeasurable. The finished height of the copper pipe is dead on all around.

Bob,
I used a dial indicator to measure the deflection... I can't remember exaclty what it was.. but I think it was 5/1000 at the base of the gantry (near the table surface) which translated to a visible difference in depth of cut... but I have never measured it as it was not critical for the part I was cutting. It shows up sometimes when I cut a larger area. If I were to guess I think it would be 2-5/1000. When I slow down the speed to 100 ipm or so it cuts better.

Overall the router is dead on with the occasional z height annoyance.

[BobF]

That sounds reasonable.
I cut at no more than 100ipm usually and I get very little variation. Probably about the same as you. I think it is within the design limitations of the machine. It you be interesting to see what can be measured on a metal machine.