Hi Peter Looks like you will have to take the table apart and investigate, it sounds as if the bearings are mounted 0.002" off centre. I had a different kind of problem with my Vertex table, in that the backlash wasn't constant all the way round, enough to cause a spacing error when drilling a ring of holes. I found this was due to the worm gear being mounted slightly off centre, but now that this is corrected, the table is fine. If I remember correctly, I had to make a special pin spanner to undo the bottom nut that takes up the play in the thrust race, and holds the thing together. Regards Ron ----- Original Message ----- From: <peter.chadwick@xxxxxxxxxxx> To: <modeleng@xxxxxxxxxxxxx> Sent: Saturday, December 02, 2006 8:28 AM Subject: [modeleng] Rotary tables > How much error is to be expected on a rotary table in terms of > eccentricity? With a #1 Morse tapor arbor fitted into the thing (the end > of the arbor is about 1 inch diameter) I get a peak to peak eccentricity > of 0.004 inches. Is this a normal level of error? MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.