[MecAut]

Hi!
I ordered recently 2x RM2005 (800 & 606 mm in length) from Linearmotionbearings2008 and my experience so far wasn't good.

The first shipping I received, both screws were shorter and he forgot to mill my key slots...
I requested the correct length and machining and after a long discussion he agreed to do the right thing. He sent only the screw.

So, I received the second batch and I found two different issues:

1) After reading several posts here, I decided to check how many balls were supplied. One nut has 61 balls, one 57 (I believe 57 is the correct number, am I right?).
2) Check the attached picture please, the surface is completely different. (on top of the picture my first order, bottom = the "fixed" order).

Is that correct? I think he sent something dodgy....

Thanks!

[MecAut]

For me surprise Chai said the difference is the anti-rust coat....but the thread shape is different.
I took a better photo

[Topdecking]

Could be coating, could just be normal variance in a rolled instead of ground screw.
What's the backlash? How well do they turn?
The issue is normally if they are bent, not if they are "off".

[Zenji]

I read a few stories like this, so I made sure I gave Chai foolproof instructions, overall lengths, standard A and B type machining.
I'll do the key ways myself before I tear down the mill for conversion.
Remember, you are getting 3 ballscrews for the price of 1 from a quality brand.

They really should just sell them with standard machining or no machining, seems like to much headache getting picky from a bulk supplier.

[MecAut]

I've just re-assembled.
The backlash is 0.15mm . I've tried to swap the nuts but the backlash still bad...
I will give up.
This product is not performing properly.

[MecAut]

I read a few stories like this, so I made sure I gave Chai foolproof instructions, overall lengths, standard A and B type machining.
I'll do the key ways myself before I tear down the mill for conversion.
Remember, you are getting 3 ballscrews for the price of 1 from a quality brand.

They really should just sell them with standard machining or no machining, seems like to much headache getting picky from a bulk supplier.

Yes.
You are totally correct. From this seller never more! It is a big crap.

[Dr.Fiero]

I'd heard a few people had issues with the machining, so when I bought my set from them I had them sent untouched.

No issues with the product itself!

Then I just machined the ends myself.

[109jb]

Ummm. 0.15 mm is 0.006" backlash. Pretty normal for rolled screws unless you repack with larger balls.

[Zenji]

Something sounds fishy, you should mike all the balls (measure), maybe check the radius of the screw thread on a light projector to see if it is matched to the balls. Sounds like you stripped both screws and mixed the parts, the different external appearance says to me that your screws have different radius and ball sizes, they are not interchangeable, they are matched.
You need to carefully go through all your parts.

Really, these guys in china work really hard for low income, plus most don't speak good english so it pays to be nice and also easy to understand.

[skray775]

I have ordered two sets for two separate builds and both times I supplied drawings of my required machining to the ends. Both sets were machined properly and to my exact specifications.

[MecAut]

Something sounds fishy, you should mike all the balls (measure), maybe check the radius of the screw thread on a light projector to see if it is matched to the balls. Sounds like you stripped both screws and mixed the parts, the different external appearance says to me that your screws have different radius and ball sizes, they are not interchangeable, they are matched.
You need to carefully go through all your parts.

Really, these guys in china work really hard for low income, plus most don't speak good english so it pays to be nice and also easy to understand.

To be honest when Chai suggested to mix the parts, my top question was if these parts are matched. He said "no, don't worry, all parts are standard and tested"...in one nut I found +4 balls lol.

Anyway I will follow your advice.

And yes, I provided the drawings and the communication was always friendly and reallysimple.

[Dr.Fiero]

While digressing from the topic....

I find it odd that some people think its ok to send messages to people quite obviously in a foreign land - and they mis spell words, use abbreviations and slang. Then don't understand why the recipient can't understand! There's a VERY good chance they'll be using a translation engine. None of which I know can tolerate the above.

Soooo... Nex time y'all dezide iza time to be slopy wit yer spellin etcetrra. Think again.