Originally Posted by
SCzEngrgGroup
My guess would be you had a small piece of foreign material on the ways. There's no way you really have that kind of contact, but whats in the photo could easily be caused by a single small piece of debris, like a single grain of sand, on the ways.
Regards,
Ray L.
Saw this post. I have an X2 and I saw this exact problem. It's hard to see/track down, but here is the reason this happens:
First, I'm going to be talking about the X axis. Everything also applies to Y-axis.
Prior to the gib being inserted between the dovetails, inspect the fit of the table to the ways. You will notice that the underside of the table has a huge gap to the top of the dove tail. Now slide your gib in. It will be nowhere near a tight fit. Additionally, notice where your gib screws press on the gib itself. It is nearly the same height as the top of the dovetail ways. The top of the screw actually applies force ABOVE the top of the dovetail on the ways. What this ends up doing is applying a rotational force to your gib. Instead of applying a straight even force to the gib, it applies a rolling force until the bottom of the gib presses against the dovetail on the table (or if you are looking y-axis gibs, on the base). Additionally, the gib height does not match the gap height between the table and ways, and the width is not the full width. This lets the gib lift up when the rolling force is applied until the whole thing finally wedges against the dovetail on the top edge, and the table on the bottom side of the gib. That line you are seeing is where the top edge of the dovetail is actually the thing making contact with the gib instead of the face of the dovetail.
The only (easy) way I can see to correct this is to remove material on the "top" area of the gib where the gib screw will(would?) contact the gib to lower the point of pressure the screw applies to the gib, and therefore remove the rotational force.
simple ascii art:
Code:
_______________
__ /
__ x / / /
/ / / <--- gib screw applying force here. Top of screw impacting above top of ways dovetail, causing rotation , Line seen from edge of ways dovetail at point x
/ /__/ /________
_______________
__ /
__ x | | /
/ | | <--- gib screw applying force here. Top of screw impacting above top of ways dovetail, causing rotation , Line seen from edge of ways dovetail at point x
/ | |/________
I'm also machining new gibs out of brass that are closer to full height/width of the space available (and brass so slide better).
I made a jig at the correct angle so it is easy to just throw some brass bar stock in and mill the gib top and bottom at the correct angle. If you end up wanting a set let me know.