We invited Chuck Austerberry from Dynamic Machine to demonstrate how to align and adjust a Citizen Swiss Lathe from start to finish. In this video, we go through each an every step in detail to ensure you know how to accurately and safely get your Citizen Swiss Lathe running its best.
Video Transcript:
Hey everyone, this is Trevor Kreman. Due to a little mishap on our SIS and L32, we need someone to take a look at it. Luckily, we have our guy, Chuck Urry from Dynamic Machine. Chuck is going to join us for a video on how to check and adjust the alignment on your Citizen Swiss lathes.
Alright Chuck, thanks for coming to our rescue. We messed it up, and you’ll get it fixed up for us. I was down the road having chicken anyway, so let’s get started. The first thing we’re going to do whenever we check the alignment on a Citizen machine is to start with the headstock. The headstock is likely unaffected by any bumper or crash. We’ll put an indicator in the headstock, come up to the guide bushing housing, and pull the housing out to sweep the casting. There is a separate casting bolted to the main casting that can shift. This ensures the headstock is in line with the guide bushing housing. From there, we can align the sub spindle to the guide bushing housing, then align the back stations to the sub spindle, and finally, line the gang spindle. This will give us a total alignment of the machine back to factory specs, and we’ll show you where those specs are in a new machine. Every machine comes with a factory inspection sheet with the inspection numbers and allowable tolerances.
Now, to get the guide bushing housing out, we need to loosen this apparatus here, which is a jack shaft. This is the belt that runs through the jack shaft and around the guide bushing, making it a synchronous rotary guide bushing setup. As the main spindle turns, the guide bushing also turns. We’re following the manual procedure for non-G guide bushing mode: loosening this apparatus, removing the belt, and pulling the guide bushing out. The jack shaft must remain straight, held in place by adjuster bolts set and locked. Do not turn these bolts, or the shaft will get cocked, causing premature bearing wear and noise.
This casting, which we’re loosening, sits against a perfectly straight stop bar. It’s crucial not to loosen the stop bar, or the jack shaft assembly will be misaligned. We’ll loosen the bolts here, remove the Allen head screws, and take the casting away from the stop block. When reassembling, we’ll pull the casting back to the stop block to ensure it’s straight and the belt tension is correct. With the drive apparatus loose and the belt loose, we can now remove the guide bushing and set our indicator to sweep the housing.
Next, we’ll remove the back portion of the guide bushing cover, allowing us to see and remove the belt from the guide bushing pulley. After removing the belt, we’ll check for any missing teeth and recommend replacing worn belts. We’ll then remove the bolts from the guide bushing housing and carefully extract it. It’s a precise fit; if it gets cocked, lightly tap it around but do not hammer it.
With the guide bushing housing out, we’ll inspect it for any issues and set up the indicator in the main spindle to ensure alignment. Using a tenth indicator for final adjustments, we’ll ensure everything is within the factory’s 15-micron tolerance. If adjustments are needed, we’ll move the casting by loosening bolts and tapping it into place.
Reassembling involves replacing the belt, reinstalling the housing, and ensuring everything is aligned. We’ll check the alignment of the sub spindle to the guide bushing, rotate the guide bushing to check its bearings, and ensure the setup is rigid for accurate readings.
After confirming the sub spindle alignment, we’ll adjust the grid shift for the X2 axis to bring our indicator to zero, using a G50 x0 command to zero out the work position. By converting our adjustments to millimeters and updating the absolute parameter settings, we’ll fine-tune the alignment.
Lastly, we’ll use the hidden page adjustment for the back stations and the B-axis stations, ensuring all alignments are perfect. By following these steps, we’ll bring the machine back to factory specs, ready for production without any accuracy issues.
This process covers basic alignment checks and adjustments. For more involved procedures, like checking squareness of the sub spindle or slides, we’ll cover those in future videos. For now, this is a good basic PM alignment for maintaining your Citizen Swiss lathes.