• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
  • PLEASE: Read the FORUM RULES BEFORE registering!

Praying just before you turn on that new lathe for the first time...

The_Apprentice

Active Member
Active Member
#1
After reading multiple issues by people with the poor performance of brand new asian lathes, I was holding my breath as I turned on my new mini tonight.

Sure enough, I had that sickening feeling when watching.

I haven't even tried testing anything with the tooling yet, as the first thing I see is the first gear rather wobbly to the point I don't even want to have anything engaged. Even with just the regular eye, I can see that the whole shaft connected to the main sprocket is rather bent off center by a significant amount.

Considering it took me a long time to drive to an area to purchase my lathe, drive back, get it down my steep stairs and set up, etc... is not something I want to do all over again.

Maybe I'll get lucky and hopefully the company will swap out an item or two with me under warranty. Or with my luck, they'll want me to re-ship the whole thing, because taking apart anything could violate the warranty.... ahah!

I'll get around to maybe videoing the issue on my iPhone for others here to examine and give input. I just don't have the time for all of this at the moment...

Stay tuned for future information on my buyer's remorse. LOL
 

Chip Hacket

H-M Supporter - Premium Content
H-M Supporter-Premium
#2
Hate that for you. Took me forever to get my new lathe off the floor onto the bench. You need Charles Atlas to move some of these things around.


Sent from my iPhone using Tapatalk
 

markba633csi

Active Member
Active Member
#3
Also consider sending the videos to the people you bought it from, if the problem is bad enough to see on a video they should send out new parts
Mark S.
 

brino

Active User
H-M Supporter-Premium
#4
I hope it turns out to be a minor issue/easy fix.

Considering it took me a long time to drive to an area to purchase my lathe, drive back, get it down my steep stairs and set up, etc... is not something I want to do all over again.
....shouldn't "Steeltown" be littered with machine tool suppliers?

-brino
 

The_Apprentice

Active Member
Active Member
#5
I should update that Brino... I'm actually not living in Hamilton anymore.

In the meantime, I took a video here showing how the gear & back end of the spindle is looking. Now, I'm relatively new to these Chinese mini-lathes, but I'm guessing this is not orthodox?

Maybe I'll get lucky and find out it's not the spindle, but just wobble produced by cheap junk they put ON the spindle? I'll take a closer look at it soon enough.


And while we are on the subject of this matter, anyone know the TOOL that is used for taking off the first two nuts that are compressed there? I see people using wrenches to do this, but I generally prefer the right tools for any job if I can. I just forget the name now...
 

Tozguy

Active User
H-M Supporter-Premium
#6
From the video it does look like the shaft itself is good.
What size of spanner does it take for the nuts? The thin long spanners for changing a table saw blade might work.
 

Cavediver

H-M Supporter - Premium Content
H-M Supporter-Premium
#7
And while we are on the subject of this matter, anyone know the TOOL that is used for taking off the first two nuts that are compressed there? I see people using wrenches to do this, but I generally prefer the right tools for any job if I can. I just forget the name now...
I believe it's this one, but they have several to choose from. Double check the size of the spindle nut.
http://littlemachineshop.com/products/product_view.php?ProductID=1416&category=

Eta: It's probably just the way they have the gear mounted on the spindle, or maybe there's some debris trapped between it and the spacer? Either way, you really need two of those wrenches to tighten things up properly. One to tighten the first nut, then a second to tighten the jam nut while holding the first one still.

I was able to make one that worked well enough using a piece of pipe and a couple of machine screws. Not great, but good enough.
 
Last edited:

RJSakowski

H-M Supporter - Premium Content
H-M Supporter-Premium
#8
From the video, it appears the bore in the gear was cut incorrectly. That would be a manufacturing defect and the dealer should stand behind the warranty. I would send them the video. The simplest route would be to replace the gear. A spanner wrench is required to remove the spindle nuts. The dealer should furnish that wrench along with the new gear.

There is a chance that there is another component which is messing up the alignment. I would expect that there is a spacer which contacts the inner race of the spindle bearing and that the gear sits against that spacer. the spindle nut and lock nut follow on the spindle. These nuts adjust the bearing preload and should not be tightened completely, The dealer should furnish directions as to how to properly adjust the spindle bearing preload.

If the dealer doesn't want you to do the repair yourself, they should ship you another lathe and arrange for someone to pick this one up . At the very least, they should compensate you for the expense and your time to bring it back and exchange it.
 

The_Apprentice

Active Member
Active Member
#9
Last night I finally figured out the name for these spanner wrenches. Took me a while, and so many other people had the same questions about them. Though the simplest trick I saw, is one machinist who just removes then tightens his chuck around the lock-nuts and manually turns it to unloosen them. Simple... Or does that sound like a bad idea?

I'm hoping it's just the spacer & gears that are wonky... we will see when I get to removing them...

And while on that note, I'm going to take a look at the motor later on today... I am curious for a closer inspection.
 

The_Apprentice

Active Member
Active Member
#10
Some of my newer tools are arriving already... though not everything just yet.
Yesterday I decided to look at the Motor, but all I found on it was a sticker with a part #, and the date of manufacture (or is that installation). Nothing about wattage.

I did notice the screws were put on very loose in many places of my lathe... too loose in many places. The first one I unscrewed to take off the splash guard (have to remove this to take off motor cover) was only half screwed in. Something else I found, seems at random they kept swapping different sized screws for the same holes. Not sure what happened there. It is a jump from 9mm to 11mm. Not a real biggie, just more of a sloppy feel to me.

I have a dial gauge that just arrived today, I'll try to use it to get some readings on the chuck, etc. to see how things line up over there soon...

Image....
 

Cavediver

H-M Supporter - Premium Content
H-M Supporter-Premium
#11
How are things going? Were you able to check runout of the spindle and the chuck?

I did notice the screws were put on very loose in many places of my lathe... too loose in many places. The first one I unscrewed to take off the splash guard (have to remove this to take off motor cover) was only half screwed in. Something else I found, seems at random they kept swapping different sized screws for the same holes. Not sure what happened there. It is a jump from 9mm to 11mm. Not a real biggie, just more of a sloppy feel to me.
Yeah. Someone here said it, though I can't remember who. Welcome to QC outsourcing; on these lathes the Chinese manufacturing company counts on the end user to be the QC department...

You'll probably want to disassemble most of the lathe to remove the crazy amount of grease (cosmoline?) and swarf left over from the manufacturing process, knock down burs and sharp edges, etc.

Once that's done you'll spend the first 3 months to a year learning how to do basic operations, and then another 3 months making improvements, and then... :D
 

Buffalo20

Active Member
Active Member
#12
When I bought my lathe, a Jet 14x40, they shipped me the 8", 4 jaw chuck, for some reason, they shipped it a week later, as it wasn't, in the crate. It came in a 12"x12"x12" box, it looked like they poked a hole in one corner of the box (vent hole), inserted the infamous red Chinese cosmolene nozzle in the opposite corner, then pumped until it came out the vent hole. When I opened the box, it looked like a solid cubic foot of cosmolene.
 

Ken from ontario

Active Member
Active Member
#13
Some of my newer tools are arriving already... though not everything just yet.
Yesterday I decided to look at the Motor, but all I found on it was a sticker with a part #, and the date of manufacture (or is that installation). Nothing about wattage.

I did notice the screws were put on very loose in many places of my lathe... too loose in many places. The first one I unscrewed to take off the splash guard (have to remove this to take off motor cover) was only half screwed in. Something else I found, seems at random they kept swapping different sized screws for the same holes. Not sure what happened there. It is a jump from 9mm to 11mm. Not a real biggie, just more of a sloppy feel to me.

I have a dial gauge that just arrived today, I'll try to use it to get some readings on the chuck, etc. to see how things line up over there soon...

Image....
Any news?, as mentioned by others it doesn't look like the shaft is bent, did you mange to find out what was loose? . I just hope it's a simple fix and you don't have to haul it back to the dealer to replace it, it was a smart move on your part not to take it all apart to fix the problem and void the warranty.
I bet you can't wait to get that lathe going and do some actual turning.
 

The_Apprentice

Active Member
Active Member
#14
Yes, I got around to giving it an examination today...

Speaking of burrs, yes that is an obvious problem I noticed on today's investigation!

Took me a while, but I managed to pry off the sprocket attached to the spindle. While being very careful not to lose the key. I measured the face of that sprocket before removal, and there was a wobble of 20 thou.

After removing it, I pulled out the cheap plastic spacer, and noticed a few things. There was a pretty bad burr on the end of that spacer where the sprocket was facing. So I am going to guess that may be part of the reason. And also, the reason for the burr, is somehow someone used something on the inside of it, and caused a very nasty linear gouge... scraping away material down the plastic spacer. I have no idea how that happened, or why one would do that.

I further more have no idea why someone couldn't just replace a 2 cent piece of damaged material, to have something proper as a spacer... Oh wait, yes I do. These poorly exploited workers who have no clue how to assemble a precision piece of machinery, assumed it was not worth the loss of 2 cents to use a piece that wasn't damaged!

Duh--

I'll do some more measurements with the cleared spindle just to make sure the spindle is not damaged, and then de-burr that cheap spacer, and see about re-assembling again.
 

hman

Active User
H-M Supporter-Premium
#15
I further more have no idea why someone couldn't just replace a 2 cent piece of damaged material, to have something proper as a spacer... Oh wait, yes I do. These poorly exploited workers who have no clue how to assemble a precision piece of machinery, assumed it was not worth the loss of 2 cents to use a piece that wasn't damaged!
Back when I was at HP and we would design/build assembly lines, then ship them to Singapore, we'd occasionally run into something similar. It seems they would sometimes have a delay in getting a new line up and running because they had a pre-set "scrap budget," and exceeding it would require management approval, etc.

I can well imagine that a Chinese factory would have little or no allowance for out-of-spec or damaged parts. Just force it on and ship it out! It may be management policy, rather than the individual worker's fault.
 

The_Apprentice

Active Member
Active Member
#16
UPDATE

Well, after de-burring the spacer, I put the gear back on. Still was with wobble, which partly looked to me due to the key causing the gear to mis-align due to friction. I tightened it some more with a little spanner wrench, and the gear fully moved in place over the full key, and now it seems to be running true when in motion.

So, for today I will consider this a success.... though the spacer itself looks to wobble a lot, I don't care about that.

So, tomorrow I'll try to pick up a can of some decent lubrication for the plastic & metal gears I have. Though I've been hearing alternating stories as to whether plastic gears really need lubrication or not.
 

The_Apprentice

Active Member
Active Member
#17
So.... now that I have resumed....

Added some lubricant to the gears, put on cover, and after everything else, I finally did some basic testing.

The good news is the 3/8" carbide tip tooling seems to fit into the post pretty good, without need of shims (so far).

I did just a facing job for today while testing... A lot more vibrations than I was expecting, but it works...

Now what doesn't work--

Noticed the Thread gauge wasn't turning. After touching it with my finger, it's so loose it's barely staying on.... Then after some investigation, I noticed the spiral-spoke underneath it was not making contact with the lead-screw. I'll have to see what's going on there.

To make matters worse, it is a real problem trying to get the half-nut to engage with the screw. I have to push really hard, and it appears to be bending the lead screw when I do this.... I don't think it was supposed to be this difficult...

I guess I will have to take off the Saddle, etc, and try to see if there is something obviously wrong with it.

Grrrrrrrr..........
 

The_Apprentice

Active Member
Active Member
#19
So.. update..

Took off the apron today and did an inspection.

Turns out there was 0 amount of lube on the half-nuts, which was part of the problem... that and I think the gib was screwed too tight.

Then to compound this issue, there was RUST on the half-nuts. I am guessing these units were sitting for years somewhere in a Chinese factory hut, with probably a dirt & muddy floor before some poor underpaid and over-worked worker decided to put them on my lathe.

Sometimes you just HAVE TO LAUGH... it's been what... 2000 years since the Roman empire, and the state of progress since then when it comes to manufacturing just has me shaking my head...

I suppose the poor worker asked his foreman what to do with the RUSTY pieces. And was properly told the half-nuts looked like they were in proper working order... leave nothing to waste!

I suppose the worker also decided not to bother adding grease or anything, simply for the fact that the rust had already started, so plainly adding more was a waste of time!

Oh that, and the fact that no one would notice the rusty units hiding behind the apron... I mean, who would think to ever look.

Now... as for why the thread dial was not working... it appears to me some genius of an engineer decided to drill the mount hole so far back from the lead screw, that it would be impossible for the dial to engage properly. I'll have to think up a remedy to fix that too somehow...

I suppose, with only 2000 years since the Romans had their own engineers, I can't really expect progress to have taken that many leaps and bounds since... I mean, just drilling a simple pilot hole, is not so simple. It requires a vast network of super-computers and advanced algorithms to figure out the proper location for a hole.

I'm already laughing here waiting to see what other surprises this Chinese lathe has in store for me tomorrow...
 

Bill W.

H-M Supporter - Premium Content
H-M Supporter-Premium
#20
Some of the smaller bench top off shore lathes are made so that the thread gauge mounting bolt can be loosened, the thread gauge turned slightly,
and therefore does not make contact with the lead screw all the time. Adjust it to make contact only when making threads... Bill W.
 

The_Apprentice

Active Member
Active Member
#21
You are right there Bill. I went to re-assemble it today and by turning it in then tightening, I got the spoke to engage.

Unfortunately, we are still left with a problem. The damn thread gauge still does not turn. Either the top screw is too lose, and the dial just sits and won't turn while the screw spins, or I tighten it, and the damn dial still doesn't spin (because friction on the bottom).

I just don't get what's with this horrible design implementation. I tried adding grease, etc. But no help..

I'll have to probably use loctite on the dial to attach it to the top-screw...

In the meantime, if I want to cut threads, I suppose I can pick a thread and gear combo so that I can engage the locknuts on ANY random point without running the thread. No biggie for now.