Syil 4th

[Six0GTO]

I would like some details on the 4th that comes from Syil. I have ordered a machine but its not here yet.

I would like to add a 3 or 4 jaw chuck to it for machining spline shafts. Do you order the chuck from Syil? If so part number? If not what have others done?

What is the actual center bore diameter thru the plate?

Is there a separate Mach3 file for use of the 4th? I have ordered a X4+ anyone with a config file using the 4th would be a great help...

[neilw20]

Inside the chuck to the adapter plate 0.625" (15.88mm)
Through the adapter plate 0.530" (13.5mm)
Through hole to adapter plate from back. 0.578" (14.7mm)

Doing splines, you will need to lock rotational clamp screws after indexing.
Doing overhung work you need a steady or a center if taking heavy cuts.

No special software required. Mach3 is 6 axis. Just tick boxes in config screen for required type of operation

Ie. shortest way to zero, or continuous rotation.... like A-5 to 1440 (4 turns + 5 degrees)

Not much point in putting a limit switch on 4th axis.
Just rotate to zero, put in job and tighten chuck.

If you did want a limit switch you would need two in series.
One on the main shaft, in series with one on the stepper motor shaft. Too hard. No gain for me.

My 4th axis limit switch circuit is now a cycle start button.


Neil.

[Six0GTO]

Anyone have an anwer on the Chuck?

[PEU]

standard 3" 7x10 minilathe chuck, nothing fancy but it does the job, like this one: http://www.littlemachineshop.com/pro...1187&category=

[Martin Long]

If you want the Syil 4th axis to use as a dividing head and only run in one direction (ie. CW) then buy one. If you want to use it as a CNC 4th Axis look someplace else because the one I bought with my X4+ is not suitable for CNC work.

Martin

[MichaelBurton]

Originally Posted by Martin Long If you want the Syil 4th axis to use as a dividing head and only run in one direction (ie. CW) then buy one. If you want to use it as a CNC 4th Axis look someplace else because the one I bought with my X4+ is not suitable for CNC work. Martin

Martin, can you elaborate a bit more in the issues where you see it unsuitable? I'm very close to making my purchase of a x4+ with the 4th axis. I was hoping it was a precision device. I'll be working with delrin mostly, but I still need it to keep a close tolerance when rotation +&- 90 degrees. Maybe you have saved me some costly headaches.

[neilw20]

Positioning accuracy is quite good as long as you rotate in 1 direction to approach you position. Depending where you are 0 to 360 deg. the backlash can vary from zero to some small amount, depending on the luck of the draw.
This is because the worm screw is cantilevered and not supported each end, and also has no preload.
The way the 'big end' of town over come these problems is to ignore the backlash, put lots of drag, more than the reacting force, use encoders, and brute force servo to the required position, fighting against the drag brake.
With this 4th axis it is impractical to climb mill for all but the lightest of cuts. If you don't lock the table before doing a significant cut, it will move.
You can position accurately and clamp and it will give excellent results.
I am using it with out locking for regrinding end/slot mills with good success. -- low cutting force.
I am also making quite nice helical couplings, (but not climb milling).
As for engraving type fwd/rev type work, expect up to 1/4 degree backlash.
There are no zeroing switches, but you really don't need such things, unless you are using some custom fixed jig mounted on it, and then you would need two limit switches in series, one on the underside, and one on the stepper shaft, other wise repeatability would be no good, hence switches being of no utility, so why have them if you can't repeat to a position at power up.
A tailstock is need if you are doing shaft work.
Positioning and centering the chuck on the the rotary table is time consuming, and once setup, you really don't feel like removing it.
All that said, it is still quite a useful accessory, within it's limits, and for the money still good value for me at least. Nice clamps and accessories etc, and a reasonable finish. The spring on the chuck key is novel. You can't accidentally leave it in the chuck (and lose your job). I ditched the spring, but nobody was watching.

[ataxy]

Originally Posted by neilw20 As for engraving type fwd/rev type work, expect up to 1/4 degree backlash.

i think the problem is mostly that you wont get constant quality on those fourth axis i am happy to see that yours as up to 1/4 degree of backlash but for comparison sake mine as up to 2 degrees.

[Martin Long]

Michael,
Neil sort of summed it up with his post, but just to elaberate a little further.
There are two major faults with the 4th axis, these faults are in connection with the two major components, the worm and the wheel.
Firstly the checknut on the wheel shaft is in direct contact with the housing, there is no thrust washer or bearing to take the thrust, consiquently when the wheel is rotating in a CCW direction (viewed from the chuck) the checknut tends to losen it's self. I have installed a thrust bearing between the nut and housing which has now improved matters somewhat.
The worm shaft is only supported at one end through an eccentric bush, as one rotates the bush, the worm is either moved closer to the wheel or further away ie. more or less backlash. If one adjusts the worm enough to remove the backlash the motor is not powerful enough and stalls. the solution in my opinion is to somehow provide support to the worm shaft, but to do this one must make an eccentric spigot to the same extent of the bush.
My 4thAxis lives under the bench until I get the time to investigate further, it has been a total wast of money in my opinion, mainly due to the fact it is not "fit for purpose", it is a shame because the x4+ is a quality machine considering the price paid. Just like buying a new car (auto) with air conditioning as an option, to stop the aircon from blowing hot air in sommer, one must first re-design it from ground up. Would you buy the same auto nex time?

Martin

[neilw20]

Horses for courses. I assumed I would get worse than I got. TLC fixed most things.