Metal lathe review coming

Started by 94touring, January 12, 2024, 07:31:04 AM

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94touring

I broke down and purchased a chinesium metal lathe from Vevor this week. It's scheduled to arrive today. I have an assortment of shop projects piling up where a lathe would come in handy, so decided to pull the plug and get a new toy.  I'll report back once it's up and running and I've done a little work with it to give a proper review.  It's the 800 watt 7x16 sized one.

skmini

I don't have a need for a metal lathe, but have always wanted one.   :grin:

Looking forward to seeing what you think.

94touring

Yeah and the more I look into machine equipment, I'm thinking a mill might be something down the road too. Gonna have to save my pennies for awhile.

cstudep

Nice, I bought an old south bend 9x48 several months back thats in really good shape for its age. I am in the process of tearing it down and cleaning it up.

A vertical mill has been on my want list for about a decade now lol.

94touring

Ok got this thing to the shop today.  Was rather heavy and awkward in its box.  Needed help getting it in my truck. They bolt it right to the box, which is nice. Once out of the box it's easy enough to pick up and move around. It's temporarily on my rolling cart till the other work bench gets in. Came with a little tool box with odds and ends and other metal gears.

Gave it a 10 point inspection like people on YouTube advised. Everything needed tighten basically. I checked alignments and those checked good. I did miss tightening a few things on the portion that holds the cutting tools.  So what would happen is it would shift around ever so slightly.  Once taken apart and analyzed it made more sense what was causing the issue.  I may have over tightened some of the slides and wheels, so will need to keep messing with those.  A couple of the handles work great, some other suck.  I will probably make my own for the one feed since the handle unscrews depending which way you're turning it. Going to keep playing with it tomorrow to see how accurate I can get a few things to fit into some needle bearings. I kept getting it close, too snug to fit, then accidentally take too much off for a loose fit. I probably just need practice.




94touring

#5
More fiddling today.  Did some learning on bits and which ones cut hard steel, once I  figured that out it was fairly easy to cut an old king pin without chatter and nasty lines.  Took the main slide apart one more time and adjusted it with a square and adjusted some tensions.  I was successfully able to cut a scrap king pin within 0.01 mm along the length of it.  I kept getting slight tapers prior.  Have 2 handles I want to replace. One was plastic and straight up broke on the dead center lock arm.

The way I checked how straight it was feeding was take a machined part, put margic marker on it, set the bit to barely touch one end. Then turning by hand, feed the bit to the middle and end to see how accurate it was.

94touring

Hotel appreciation week at work in Dallas so time to watch YouTube vids on Chinese mini lathes.  One of the things I noticed on my feeds is the top slide is loose on one end and tight on the other if the gibs are adjusted to perfect tension at the mid way point. Which if you're going full travel either makes it really tight to operate or the assembly itself loose at the other end. Apparently this is a common problem amongst all these mini lathes that more or less use the same parts.  The issue are the gibs that adjust the slide tension are pretty crap.  A bad fit and usually not straight, which makes sense given my issue with it. There's a machine shop online that makes all sorts of little odds and ends for these mini lathes that has a set of bronze gibs that are the solution. Ordered a set which should be there by time I get home from this trip.  Another item I'm considering is a vertical milling slide.  It would be perfect for small milling projects with milling bits attached to the lathe head. 

MiniDave

Ok, once you get this one all sorted and working correctly, you'll decide you need a bigger one so I'll buy this one from you then!   :grin:
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

94touring

Ha!   There's quit a few tricks and things people do to these.  I plan to make some locks for both slides, which once I get around to that I'll show pics and explain the purpose.  It really comes down to the more rigid you can make it the better. There's also maybe a plastic race along the motor shaft that I should turn down a piece of steel to replace. Makes a smoother operation from what they say. 

94touring

Needed to create some bushings today.  Went pretty quickly getting the OD to 29.5mm.  One thing I added was a dial indicator to check for runout before I start turning.  After watching YouTube clips learned that one of the three chuck tighting spots will be most accurate.  I found the one that's under 3 thousands and marked it as the tightening spot.  Here's a before and after on a bushing I needed to make.

Also did a test run creating a specific bolt I need for another project.  Not entirely happy with the first rendition but will go again.  The head is particularly tricky.  Will need to thread the final piece once I'm done.

94touring

Much better on the 2nd attempt.  I left the head a little oversized. Started with a large 10.9 grade bolt.  Once threaded this will replace the bent bolt on my rear disc calipers on the mini. 

MiniDave

Did you find a 7/16-20 die to thread it with?
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

94touring

Amazon in a couple days should have it.

94touring

Another lathe job success.  The bus steering column had a wrong sized plastic bushing. The OD was too big, not allowing it to sit into a slot, and the ID too big making it sit loose on the shaft.  My steering column would shift all over.  New one in place and took out all the slop.

Willie_B

That is the stuff that makes having a lathe wonderful. You will continue to discover what it is handy for.

94touring

Sure does!  I have some more bronze bushings to make for another project too.  Today I finally got around to actually bolting the lathe to the work bench.  Won't be vibrating all over now.  I am thinking of anchoring the bench to the wall or floor also.  One other little mod I made today to the lathe was on the main slide.  The front gib/plate that slides along the frame sits flush but the rear gib/plate is at an angle.  So there's minimal surface area actually riding on then frame.  This allows for unwanted movements.  All I needed to do was dig through my bins and in my copper washers found the perfect size to use as spacers between the gib/plate and the 3 bolts that torque it to the main slide.  Once the spacers were in place it sat flush to the frame.  Slides nicer. 

94touring

Finished off threading this bolt.  Here it is beside the bent one it's replacing.  This is what holds the pads on my mini rear disc. With it bent, it's a real pain getting the pads on. 

jeff10049

That's cool, lathes are damn handy to have around I use mine a lot id be lost without it. Mills are great too but the mill will be the cheap part tooling adds up fast for a mill I was pretty excited when I got my mill then realized I needed to spend another 2k to be able to do anything with it. 
When you get more comfortable running the lathe you can cut the threads right on the lathe it does a better job than a die. Assuming it has inch threading capability.
If you search Mr Pete on YouTube he has some good machine shop teaching videos. I also like the home model engine machinist forum.

94touring

I have a bunch of updates to post about but have been out of town awhile.  I've added slide locks, a better compound slide from littlemachineshop.com, and have some taper bearings to replace the radial style grooved ball bearings on the spindle. The bearings are supposed to make a big improvement.  But also I managed to burn up the motor!  As it turns out the motor on this particular lathe is built around the spindle and enclosed into the head stock.  I've read there are benefits to this style motor, but I would venture to say a negative is the lack of heat dissipation. I melted the thing pretty good.  Now that being said that gives me an opportunity to give a review on Vevors customer service.  It was good!  Albiet a little slow and there's some communication issues because you're dealing with people in China.  So I called the number and spoke to a lady on the phone who then entered in my information to be sent off to the folks in China. She said I'd get an email within 24-48 hours. I think I got the email about 12 hours later in the middle of the night. They wanted pictures of the broken items.  It took me some figuring out how to get into the head stock and remove the spindle, but I could be qualified as a certified lathe mechanic at this point. After every email exchange you wait 12-24 hours, but they do respond and try to help.  They decided to send me an entire new headstock with enclosed motor and spindle.  They kept me updated on the status of the part and once it finally got to them it shipped quickly via DHL.  Ok so that being said I now have 2 head stocks.  One replacement and one that's empty with just the spindle after pressing the motor out.  This got me researching into other styles of motors as a spare.  What I have sitting at home for me once I finish this work trip, is an 1100 watt motor and associated motherboard.  As it turns out the electrical portion of my lathe uses a somewhat universal board which is plug and play to all the various components and switches/buttons ect..  However they're specific to the watt rating of the motors so I couldn't use my 800 watt board with this 1100 watt motor.  But they're not expensive.  The plan now is to swap the new headstock and motor back on, plug it all up, and then given the dimensions of these taper bearings,  I need to turn down approximately 5mm off the old spindle shaft on the one end for things to come together and line up perfectly.  I need to fabricated a couple spacers, bearing covers, and a few other odds and ends to add this external 1100 watt motor.  I was able to get a belt, associated timing pulleys, and keyways for this new setup. I need to fabricate a way to mount the motor.  Once it's all lined up and ready to be mounted, I can take off the stock 800 watt headstock and put the 1100 watt taper bearing motor and headstock on.  The 800 watt head can sit on the shelf as a spare for if and when the 1100 watt motor dies and I really have to finish a project.  I'll have pictures soon showing all this.

jeff10049

Cool, as I was reading I was thinking put an external motor on it LOL. I had an HF 9x20 for a while after a few mods and little machine shop upgrades it was a pretty capable small machine. I sold it and got a like new atlas I think its a 10" swing with a factory cabinet stand and underdrive motor set up for a small lathe, it's sweet. My bigger one is an old JET 14x40 I like it.
The import lathes are pretty good I'd rather have one and work the bugs out than an old clapped-out piece of American iron. But if you come across a good condition small Logan, Atlas, Crafstman, or Southbend Grab it they are night and day to the imports the downside is you may not have metric threading capabilities but with some change gears that may be overcome.
Then again once you get yours modded out you may not need anything bigger/better.

94touring

Yeah the fun part has been the mods and making improvements to it. You learn there's so many tweaks to get it dialed in perfectly. It becomes a competition to see how precise you can make it.

94touring

Ok today decided to get back to the lathe.  Installed the new stock head unit and got to working on fabricating the old head unit to accept the taper bearings.  I fiddled with the business end of it for awhile trying to determine how to best seal the bearings, yet not seize up once torqued down.  I took off a fair amount on the spindle, used a huge washer, and rubber seal fit to size.  Turned out perfectly.  The non business end required spacers. Took 2 of the huge washers and turned down as required to fit against the bearing, and another as a spacer to align the one gear, as well as one to install the 4 tiny magnets for the rpm sensor.  After that was completed, I needed to cut up the metal housing that all the switches and panels attach to so that the motor belt could feed through.  After a few adjustments it all fit great.  I have yet to mount the motor but will need to make a custom bracket.  Once wired up to do a test run the new control board would turn on, but the motor didn't do a thing!  Hooked up the old board and it would run, albeit a tad slow, which makes sense seeing how they said it needs a different board per the wattage of the motor.  Anyway hooked the new board back up and decided to move a 3 wire clip over to an unused plug on the board.  Both boards have the same configuration and clips, with one 3 wire plug unused. Once swapped to the other plug she ran, and faster too.  Pics of the work...

One pic is of the original rpm sensor spacer on the spindle and the next pic is what I made to work with the new configuration.


MiniDave

What are you using to lube those tapered bearings? Did you put a zerk fitting in somewhere so you can grease them periodically or are you using a drip oiler?
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

94touring

A multi purpose lithium type grease.  A bit thinner than your red high temp bearing grease.  No zerk fitting but I could use something of needle to inject past the rubber.  Although honestly I will probably just removed the assembly periodically to service. It's not hard to take apart.

94touring

Ok we have a spinning lathe using an external 1100 watt motor and taper bearings.  Only thing we don't have is a tach.  Maybe this board isn't compatible with the tach I have.  Not that it really matters, so long as I have variable speeds.  This motor seems faster to me, maybe I can check manually at some point to verify.  I was mainly concerned and curious what the runout would be after it's all said and done.  It's very good!  Checked a number of spots just to see.  Thrust on the spindle is maybe 0.0005.  Inner spindle through hole shows 0.0015. Outter perimeter on the 3 jaw head shows 0.0005.  And a machined steel bushing shows 0.002.  I'll take it. 

Here's how I ended up stuffing the motor in there.  I need to make a cover for the fan end of the motor so it isn't sucking in metal shavings.