Gary Campbell
12-18-2007, 07:47 PM
Its time for the 6 month check up/tune up. We were experiencing a pronounced chatter during certain cut directions, mostly -X moves into CCW turns. Happened with various materials, bits, speeds, etc. I had the motors off, checking and tightening etc. and noticed I had some loose rollers in different areas of Z position and there was a fairly stiff bind in 1 spot. I decided to completely remove the Z extrusion and find out the whats and whys. Here is what I found:
1) The bind was the top mounted Z stop bolt hitting the pinion at the lower end of the Z movement.
2) The 4 mounting areas for the Z rollers were not a consistant width.
3) The Z rails were not parallel with each other. (looking from the side formed a shallow X)
4) The Z roller mounting blocks were not parallel.
5) The eccentric adjustments for the Z rollers were at the end of their adjustment range.
I dont know if this is normal wear and tear or had been there all along, or maybe some of both. Here are my fixes:
1) Replaced 1/4" hex bolt & lock nut with socket head cap screw & lock washer.
2) Each of the 4 "blocks were mic'ed and .010 shims were added to get them all to within a few thousandths.(see pic)
3) Z extrusion clamped to cast jointer table and Rails were retightened parallel to extrsion and themselves.
4) The bolts were loosened and I placed a block of Ipe that was cut parallel to the right dimension. Mounting blocks were clamped together tight to the wood block and retightened.
5) During step 3) above I added a .020 1.5" sq. slotted aluminum shim behind each bolt. This allows a better adjustment range. (see Pic)
Hope this can help someone that may have similar problem.
Gary
3775
3776
1) The bind was the top mounted Z stop bolt hitting the pinion at the lower end of the Z movement.
2) The 4 mounting areas for the Z rollers were not a consistant width.
3) The Z rails were not parallel with each other. (looking from the side formed a shallow X)
4) The Z roller mounting blocks were not parallel.
5) The eccentric adjustments for the Z rollers were at the end of their adjustment range.
I dont know if this is normal wear and tear or had been there all along, or maybe some of both. Here are my fixes:
1) Replaced 1/4" hex bolt & lock nut with socket head cap screw & lock washer.
2) Each of the 4 "blocks were mic'ed and .010 shims were added to get them all to within a few thousandths.(see pic)
3) Z extrusion clamped to cast jointer table and Rails were retightened parallel to extrsion and themselves.
4) The bolts were loosened and I placed a block of Ipe that was cut parallel to the right dimension. Mounting blocks were clamped together tight to the wood block and retightened.
5) During step 3) above I added a .020 1.5" sq. slotted aluminum shim behind each bolt. This allows a better adjustment range. (see Pic)
Hope this can help someone that may have similar problem.
Gary
3775
3776