[mikemill]

There has much criticisum of the 4th axis table supplied by Syil, some saying due to the backlash the table is incapable of accurate work, also some very complex solutions to the percived problem. But I wonder how many are aware of the adjustments on the unit, as Syil products come with little or no documentation and what state they leave the factory is questionable ( remember crimps ) it is therefore a good idea to adjust the rotary table prior to use.
With the unit clamped to the mill in the vertical mode losen off the two recessed hex grub screws on the top of the base casting, the worm is mounted in an offset coller so as you rotate the coupling housing clockwise the worm ingages into the table gear and vice versa. Rotate the worm anti clockwise to dissingage and then rotate the table by hand to establish any play, in the base is a threaded ring secured by a screw, losen off screw and turn ring thus locking table, now back off ring untill it turns freely without any play and tighten screw.
Now turn motor housing to engage worm tight then just back off again, and tighten grub screw, you can make this adjustment with the motor running to prove its not to tight to run freely. If the motor housing is now not square with base lossen off the two cap screws and adjust to suit.
Regarding backlash ,those of us who learned their engineering on conventional
mills and lathes knew no different, as long as the table screw is turning in the same direction there is no backlash, as the name implies it only occers when the screw changes direction, so ergo if you run your 4th axis in the same dirrection to cut your part you will not encouter any backlash.
There are many posts on this site by people asking for advice on what machine to buy, nobody has invented the perfect machine tool ,they all have there sortcomings, Syil gets its justified share of criticisum ( and I have made my feelings known ) but in the right hands this value for money tool is capable of accurate work. I recently made some small gears useing the 4th axis, and they run very well.
Thanks
Mike

[Journey_Man]

......but in the right hands this value for money tool is capable of accurate work. I recently made some small gears useing the 4th axis, and they run very well.

Mike I Agree with you 100% I have proved your underlined statement way too many times with my lathe! I appriciate your post & the information that you added in "tweeking the rotary table" Thanks Man.

[iGG1e]

I'd say not all of them come out of the factory equal. The mild steel shaft in mine makes it impossible to get anything close to a little backlash before it binds like there's no tomorrow. Unfortunately I want turn in both directions and this just isn't up to the job. I'm going to convert it back to what it should be, a manual rotary table and I can use it on my manual mill.

The Sherline rotary table looks about the best as they've made the worm so it is supported at both ends. A pricey little unit though. One actually on German eBay...some very nice stuff on theirs compared to ours.

I'm going down my own route.

[mikemill]

iGGIe
Assuming you bought your mill from Hugh, ask him to replace the table with one that works. As Syil monitor these pages I am sure they will support thier dealer.

Mike