Disassembling the CJ0618 7x12 Lathe, Cleaning, and Troubleshooting

welcome to adventures with a very small lathe this is a 7-inch mini lathe this design is usually attributed to the Zeke model c2 and is available all over the world there are many different brand names and sometimes unbranded as far as I can tell this one was manufactured by real bull machine Tool Company in China it was sold and branded as part of a very cheap batch and based on the number of problems it has I'm guessing it was a batch that failed quality control [Music] I bought it because I get a lot of comments asking how the proc son compares with cheaper Chinese lathes and I was curious to find out I unboxed it and tested out in an earlier video and found a lot of problems so the best next step look like stripping the lathe down into parts cleaning it thoroughly and finding all the problems need to be corrected before it can be used safely [Applause] the first time the lights powered up it makes this horrible rattling noise with no obvious signs of where it's coming from the first obvious thing to remove is to chuck it's held on by three threaded stubs through the spindle plate and held in place by three nuts which can be removed with northernly spanner or wrench the back of the Chuck doesn't look right at all the mechanism is completely exposed which is great if you want to see how a scroll truck works but means it will get clogged with chips the chuck should be completely sealed at the back like this Chuck from the procs on lathe this will need to be fixed if the chuck is going to work reliably the next obvious things to remove are the tailstock and the carriage the tailstock should just slide off this end of the bed but I'll need to remove this screw first it looks like there's some paint spatter on the screw and the surface of the bed which is probably from where the pain was touched up after the lay that was assembled the splash guard is obstructing access to the carriage so I'm removing that next the most difficult screw to get to is this one on the underside of the headstock end the next one is more obvious on the other side just under the Chuck the final screw is right at the tailstock end I'm not likely to reinstall the splash guard as it gets in the way of the camera when recording video and I fill almost all the machining work I do to remove the carriage I'm going to need to break it down into its three major components the compound the saddle and the apron the compound needs to come off first needs to be pulled all the way back to expose the two screws holding it in place on the saddle the next two screws attached the saddle to the apron removing these will allow the saddle to move freely and slide off the end of the bed leaving the apron engaged with the feed rack and leadscrew the saddle sticks a bit at the end of the bed it looks like this is due to stray paint on the slide ways especially on the underside here are notice that the hold down plates on the saddle are at a strange angle I'll need to look at this in more depth later the only thing preventing the apron from coming loose is the half nuts even though it's disengaged is still enclosures the lead screw to touch it I'll need to remove the clip and allow the half nuts to come loose the gape seems very poorly fitted it turns out the holes for the Gib screws don't line up correctly so ideally would be replaced with a new clip with the correct alignment the next thing I want to look at is the drive mechanism in feed gears when I tested out the lathe it made a lot of noise and the spindle didn't turn properly the first obvious problem is with this feed selection lever he works fine in forward in reversed directions but in the center position doesn't disengage properly the range of movement where the gears are completely clear is very small and the levers alignment is slightly off meaning that the gears rattle and feed screw turns when you shouldn't in addition there's a lot of play in the leave of mechanism so even if the center detent was in the correct position it still would probably not disengage reliably to get a better look at this lever I need to disassemble the gear train so I'm going to start with the larger gears at the bottom the screws are easy enough to remove with the gears themselves are very firmly in place as they're made of plastic and very cautious about using too much force to remove them looking more closely at the lead screw gear the plastic is cracked at the keyway it looks as though they weren't fitted correctly removing them is almost certain to damage them further so I'll need to buy replacements I know the metal replacement sets are available so I'll be on the lookout for one of those removing the screw on this central gear doesn't seem to make anything easier to remove so I need to look for other options while I can't easily remove the gears loosening this nut allows them to be moved down disengaging them from the gear above and making room for the rest of the mechanism to be removed with the lower gears out of the way the central mechanism can be removed in one piece by removing these two screws the feed Direction leaver is now completely exposed and only held in place by this last screw with the top part of the gear train remove they should be able to get to the drive mechanism by removing this panel when the lights turned on the spindle turns but it makes a loud noise when it's under any load now the belts exposed it's clear that it's way too loose and slips very easily the belt goes directly to the spindle from the motor but I can't see the motor clearly without removing more of the casing the Chuck got cut off switch is in the way of removing the motor cover so that looks like the right place to start it's straightforward to remove by taking out the two screws holding the switch in place and the four screws holding the conduit the top two screws in the motor cover are now easy to get to and remove the final screw holding the cover in place is in the bottom corner once the cover is removed we can see that the motor is loose which would explain why the belt isn't tightened properly the motor mounting and all wiring are on the other side of the bed casting on the other side of the lathe everything is covered by this control panel casing so that needs to come off is held on by four screws and removing the bottom two first avoids the case falling off unexpectedly the power cord wires connect through these two terminals so I need to disconnect them before the casing can be removed the final earth connection of the cord is screwed into the headstock casting on the control panel side with the cover out of the way the motor can be temporarily wedged into the correct place using a bit of scrap wood but this obviously isn't a good permanent fix the belt pulley is held in place by a single screw but once the screw is removed its firmly in place enough to need to be prised off now everything is out of the way that we can see the motor mounting studs are loose and look bent the reason this has happened is they're much too small for the mounting holes in the bed casting and only the very edges of the washers are in contact with the face making it very easy for them to bend washer should be clamped between parts not stretched across a gap like this while the ladies on this side is a good time to remove the lead screw which is fixed by hanger bearings here at the head and here at the tail of the lathe this plastic shield looks like it's there to keep the wiring clear at the leadscrew mustn't lose these two washers which were between the motor and the bed casting the next major stage is removing the headstock which is held on by four screws I didn't get any footage of removing the screws on the far sides of his footage of screwing them back in played in Reverse under the headstock there's a load of that mixture of oil and grinding grit which needs to be cleaned off most of the lathe the last part still fits the bed is the feed rack the screws look as though the heads have been ground until they're flat with the surface and there's barely any of the hex left to engage with I only managed to turn this screw a little before the hex was entirely stripped so I decided to skip removing the rack for now the layer of gritty grime dissolves away easily in wd-40 but once it's been wiped away it's a lot more clear how much paint spatter there is towards the tailstock end water-based paint stripping gel should make it easy to remove the spatter without the need for any sharp scraping tool which might damage the ground surface while I'm waiting for the stripper to take effect I also want to remove the paint from the points where the lead screw hanger bearings are mounted this will make sure there's metal to metal contact which will ensure the feed is as rigid as possible the paint layer on this part of the bed is thick so plenty of gel is required to strip it after a few minutes to dissolve the paint spatter wipes away easily with a rag and some wd-40 ensures no water from the gel is left behind the paint layer on the bearing mounts are softened but not enough to entirely remove it so another layer of gel is required after about 20 minutes the paint is soft enough to be completely removed to make sure there's no moisture left behind I need to flush out the screw holes with wd-40 and compressed air the next obvious place to clean is the ramp there's a slot dirt from between the teeth and between the rack and the bed I used more compressed air [Music] halfway along Iraq I stumbled across this it looks as though a filler material has been used to smooth the casting and a bump is obstructing the feed pinion that runs along the rack to prevent the rubbing I need to file it away using this Teflon shim to make sure the file doesn't damage the rack the slide way on the other side of the bed is much easier to clean the last remaining slight ways on the bed are on the underside of the middle which the tailstock hold down plate grips these turn out to be covered with a lot of paint so I need more stripping gel the webs of the bed make it very difficult to get to these ways and make it especially difficult to apply enough force to scrape away the paint properly eventually I get the way it's completely cleared and wipe down with wd-40 the next problem with the bed of the burrs all the ground faces have sharp edges in the field like there are burrs in every corner these birds can cause contact surfaces to wear in a sharp enough to hurt if I rub against them I need to make sure I don't damage the ground surfaces when removing the burr so I'm using a bench stone to break them smooth for each edge I run the stone along at different angles to catch every part of the bird but make sure the stone doesn't come into contact with the flat surfaces once the bars gone I smooth the corner with a finer grit side of the stone the sides of the bed are not ground and not contact surfaces so I'm studying the faces more directly the edges of the inner sides of the bed are not more difficult to get to so I use a smaller stone the under edges are more difficult still so I'm using a very narrow abrasive stone a lot of patience [Music] to dress the ground places I use this pair of fine diamond home stones ideally I would use a pair of precision ground flat stones but they're very expensive for my little shop precision ground flat stones have been ground extremely flat using a diamond wheel and a surface grinder this makes the force between the stone and a flat metal surface so low the stone doesn't break the metal ensuring only a very small protruding Nicks and burrows are affected leaving the rest of the face untouched my diamond tone stones are a poor substitute but with caution they allow me to clean ground without surfaces without damaging them faces on the underside a machine but not ground so I'm using a normal stone to smooth away some of the machining marks [Music] after all the deferring the bets need a wipe down with wd-40 to remove the chips when he lose some abrasive from the stones the bed is now done but there is still this big pile of other components to clean the first parts to remove are the hold-down plates from the saddle which are attached by these three screws most of the carriage parts are small enough to go into the ultrasonic cleaner which can thoroughly clean decrease and remove any grit and abrasive from the parts of the same time these three screws on the side hold the cross light give in place removing them should release the Gib the Gib slides out pretty easily but the cross light is still held in place by the lead screw cross light should just slide off the end of the saddle once the nut reaches the end of the screw winding the cross site off the end of the travel turns out to be a lot easier with a handle reinstalled the handle is attached to the end of the lead screw by this single cap head screw the scale is held in place by a retaining screw the last part of the cross feed assembly is attached to the saddle by two screws at the bottom of these two holes [Music] the sun'll is now stripped down but is still covered in gritty grime like most of the life it's much too big to fit into my small ultrasonic cleaner so I'll need to clean it the same way as I cleared the bed the final thing to remove are the plastic wipers these wipers are intended to prevent swarf and chips from getting between the subtle in the ways they also help keep way I'll wear belongs I'm unsure how well this black plastic style of wiper works and I'm considering replacing them with felt wipers which I've seen on most professional lathes I've used the last parts are removed from the cross light is the feed screw nut it's held straight by these two screws all the small parts now go in the ultrasonic cleaner I'm using bike chain cleaner as a degreaser as it's much easier to care hold often specialist ultrasonic cleaning fluid I dilute it with boiling water as ultrasonic cleaners work better when the solution is warm but this cheap little cleaner doesn't have its own heater once the cycle is run I remove the parts from the obviously much dirtier degreasing solution shaking loose any debris which has been dislodged by the ultrasonic cleaning process I empty the parts onto tissue to dry and rub off any external moisture I then use compressed air to remove moisture from the holes of inner surfaces once they're dry I move the parts onto a fresh tissue and spray it with wd-40 to prevent corrosion and displace the last remnants of moisture the larger parts need to be clean the same way I clean the bed using wd-40 in a cloth this is quite a lot more work than the bags to shake is more complex and there are more difficult to reach places where it could get lodged once they clean ID bar the parts where the Stein just the same way as I do [Applause] [Applause] [Laughter] these two flat surfaces are where the hold-down plates are mounted they have some raised edges around the tapped holes and some rough machining marks so I stolen them more aggressively before dressing the ground sliding surfaces are clean off the swath and free abrasive by wiping the parts down with more wd-40 to reach the insides of the dovetail ways a triangular stone is required so I'm hunting down the faces of this triangular stone so I can use it to remove fine bears and dings the same way I'll use the pair of diamond home stones on the surfaces of the bed after a few passes the sound of the Sony changes to a softer sliding tone which I think means this stone is no longer cutting metal I can clean any exposed slide waster with the same pair of diamond tone stones that I used before the tool post provided with the lathe has already lined up to be replaced with a much more useful cuneiform gipfel ghost movie video is quick to make than this one so I uploaded it a few weeks ago the next part I'm most key to replace is this cheap-looking a plastic angle scale I'm determined to replace this with something less chintzy so I'm never going to put this one back on the gear retaining screws work just the same way as on the cross slide all the compound parts will fit into the ultrasonic cleaner so I'll turn it that way then debone in the same way as the saddle the compound slide is already round to almost to the end so it comes apart easily while the handle is attached the same way as the cross light the rest of the assembly looks a lot more clumsy these two nuts are locked together and seem to act so spacer between the handle and the scale the scale is helped by this retaining screw and is the only thing left holding the lead screw in position this last part held on by two screws is little more than a spacer and a reference point for the scale cleaning and deburring was exactly the same as the saddle so I won't bother showing it here the final disassembly is the tailstock the bottom plate to sell them to the main body by this single cat screw undone from the underside there are two retaining screws on the site Rifat the horizontal position but there are reduce removing this retaining screw releases the locking lever and allows the locking mechanism to slide clear it's a bit gummed up with paint it eventually works free the cool lock handle comes off easily by unscrewing it leaving this bushing in the hole the core can now be extended until it runs off the end of the Leidseplein is free the bushing isn't fixed in place but is hard to get a grip on to remove it the central stud for the locking mechanism is just screwed into the casting now everything's removed I can see that the locking bushing also acts as a key to hold the quill straight which fills a vector G the feed wheel is held on by this retaining screw on the side and also by a knot on the end of the spindle shaft the Shelf is held in place by this ring which is fitted with two top screws most of the parts go into the ultrasonic cleaner but the casting is too large needs to be clean separately the pen work cleans up okay but the bottom mounting surface is quite a mess it's covered in rough machining marks is very corroded this surface release to be real machine but at this point I don't know how much detail I have to play with so I look at this once the machine is back together and I can try and see whether the tailstock can be made to align with the spindle this is the underside of the base which rests on the bed but unlike the saddle there's no sign of any ground surfaces so I don't worry too much about staining the burrs carefully the top side of the base is where the main body of the tailstock rest so I need to clear up this paint to make sure of a good contact I didn't bother with stripping gel though as the paint's soft and scraped so easily here of the quality of the tailstock is so bad I'm not even sure it's colorable but I'm gonna keep working on for now as it's part of the lathe package the whole lathe has now been disassembled most of its clean than it was this video has already gotten longer than I planned so the reassembly will be the next chapter of the story in a video of its own this video took me a while to make and I know a lot of you were waiting so thank you all for your patience the assembly video is already in production and shouldn't take quite as long I also have some machining projects and tour reviews in the pipeline so I'll see you all soon you

Channel: Adventures with a Very Small Lathe

Views: 285,534

Keywords: Lathe Disassembly, Lathe Disassembling, Lathe Cleaning, Lathe Troubleshooting, CJ618 Lathe, CJ0618 Lathe, Mini Lathe, Sieg C2, Sieg C2 Lathe, Lathe Projects, Mini lathe Projects, Home Machine Shop, Chinese mini lathe, home machineshop, machinist, machining, 7x12 lathe, 7x12 mini lathe, 7x14 lathe, 7x14 mini lathe, lathe

Id: URnLbHOrpnQ

Length: 36min 10sec (2170 seconds)

Published: Fri Feb 14 2020