Inaccurate cuts, Slop in torch lifter / gantry

[OcalaWill]

I’ve been cutting some designs that have concentric circles and have an issue where the material between the cuts gets narrower or wider at different points. So I checked the table for level and squareness and it is ok. What I found is the lifter station will rock in the Y axis direction if I grab a hold of it by hand. Could this be the issue? I took the lifter station off and some of the bearings will rotate if I touch them (not contacting track). What is the adjustment procedure for this? I went thru the manual and couldn’t find anything. Table is a 4x4 GS. Thanks.

 

[BlueSteel]

did you check for a cracked bearing?

 

[OcalaWill]

did you check for a cracked bearing?

No, but table has extremely low hours so a bad bearing is unlikely imo.

 

[BlueSteel]

has little to do with the amount of use IMO. I've done 2 bearings on mine...One lasted a year and the other a few weeks

 

[Dnmeistr-LECS]

A cracked bearing wont cause that, and you would hear the bearing cross the joint of the crack if that were the case. Which bearings rotate, you have the bearings that ride on the 1/2" flat bar and you have the bearings that ride on either side of the upper and lower track. If it is the upper and lower track you can loosen the bolts and the bar that holds the two bearings can be twisted so the two bearings make contact with the track.

 

[OcalaWill]

A cracked bearing wont cause that, and you would hear the bearing cross the joint of the crack if that were the case. Which bearings rotate, you have the bearings that ride on the 1/2" flat bar and you have the bearings that ride on either side of the upper and lower track. If it is the upper and lower track you can loosen the bolts and the bar that holds the two bearings can be twisted so the two bearings make contact with the track.

When you say the bar that holds the bearings are you talking about the 4 aluminum blocks?

Please see picture. The plate with the 4 welded long hex nut mounts for the lifter station bracket is loose. By loose I mean I grab the right side hex nuts and the plate will move in and out 1/16" . The left side seems ok. What is procedure for tightening this plate?

If I wanted to remove the whole assembly to inspect what is procedure? It doesn't look like it will come out whole as the gantry has the two upper and lower bends that recess everything. Do all the tracks need to be removed and everything removed as group?

Thanks.

 

[OcalaWill]

has little to do with the amount of use IMO. I've done 2 bearings on mine...One lasted a year and the other a few weeks

If I can get this apart I will inspect. Thanks for your help!

 

[Dnmeistr-LECS]

The two front facing allen head bolts in the picture you attached are there to pull the bearings into the 1/2" flat bar, there are 4 bearings on the front side and two bearings on the back side. The two allen head bolts when tightened will pull the two bearings in the back taking up the slack, preloading the front 4 bearings and the 2 back bearings. See pic of the back side of the cassette. I would not recommend pulling the cassette out, as you would need to remove the 4 aluminum blocks, remove the two allen head bolts on the back side that secure the aluminum bracket where the anti-backlash nut is screwed into as well as remove the 1/2" flat bar from the gantry, taking out the flat bar and cassette as a whole. Where reassembly needs to be spot on to get the cassette back in line with the acme screw.

 

[OcalaWill]

Ok I understand how to tighten up the cassette, but how do I take up the looseness in the plate since those are fitted inside the cassette (?) It looks like those two plates need to be spread apart (4 screws/nuts) to wedge - is that correct?

 

[OcalaWill]

Ok I got this snugged up nicely. Thanks for all the help!

 

[BlueSteel]

all better? What fixed your issue?