Thread: Beware of buying counterfeit bearings

Originally Posted by Dave J

Does it make the same sound with the quill up and down?
It might be worth a try while your waiting to make one of these spline clamps that will lock the 2 pieces together to see if that eliminates the noise.
Article - Mill Spline Clamp
I want to make one of these myself to fit to my machine. If you are interested I could find the detailed drawing online and if I cant, I have a copy on my computer that I could send you, it's very simple.

Dave

yes up or down it can become noisier depending when you lock the Quill depnding on where the quill position is. I have also rotated the quill clockwise one spline at a time within the female spline so that it was located in a different slot each time..no difference

I will read the stuff on that link

You wont need the release jig talked about on that page.

Dave

i forgot what why i went there...i got carried away looking at some other stuff on there...tool cutter grinder...for one, then followed some links elsewhere and got tied up...

oh yeah what was i saying...i will print it out and read it thouroughly...that way I wont er cant follow anymore links

Originally Posted by Dave J

Eskimo,
I found a brand marking on one of the original bearings on my mill, they are HRT (Chinese) brand bearings.

Dave

I was wrong in the brand of the standard bearings in the HM52, they are HRB not HRT.

Dave

Originally Posted by Dave J

I was wrong in the brand of the standard bearings in the HM52, they are HRB not HRT.

Dave

same sounding letters

Hi Eskimo,
The HRB bearings come from India, below is from there web page.

JAIPUR BEARINGS LIMITED
Manufacturers & Exporters of Bearings
F-2, Gawri Bearing Market, 5200,
Shardhanand Marg, Delhi-110006, India
Tel.: +91-11-23215754, 23215136
Fax.: +91-11-23214695
Website : HRB Bearing

NARANG MACHINERY STORE through years of hard work, perseverance and business integrity has developed into a well established national leader in bearings distribution in INDIA.

Extensively exported to Africa, Asia and Europe, (80% of the production is earmarked for exports). HRB products cater to diverse industries in the Automobile, Agro Equipment and General Machinery sectors. With an all India network of dealers and Corporate Office in New Delhi, HRB reaches out to customers, delivering products almost at their doorsteps at competitive prices and at right time.

I had a look at their site and from what I can see, they don't make precision taper roller bearings, only standard. So the P6 stated in the manual is probably for clearance not precision. The local bearing company got that mixed up when I went to get my bearings.


The RHP range of Super Precision bearings includes a full range of single row angular contact bearings and deep groove ball bearings that are designed to meet the following requirements:

• Extreme accuracy
• High rotational speed
• Quiet and smooth running
• Minimum friction and heat generation
• Controlled rigidity

I just got a quote back from one local bearing supplier for P5 or ABEC5

There is a 8-12 week wait for them.
30308 = $122+gst
32009 = $146+gst
32010 = $184+gst
32011 = $224+gst
= $676+gst
-------------------
= $743.60 inc gst
At that price I think I will leave them. I am still waiting on a quote from the US where a guy from over their gave me a lead. His 2 bearings a little smaller than these ones only come to $146 for the 2. At around that price I would consider them.

Dave

yes... they are a tad expensive are'nt they...If i recall correctly the prices I got back from CBC for a angular contact for the top was in exess of $300 ex GST....each

the delivery time was what changed my mind...lol

What sort of discount are you guys getting from the bearing shop?. One old engineer I know showed me invoices from Bearing Services with a routine 70% discount on the NSK bearings.

Originally Posted by Graziano

What sort of discount are you guys getting from the bearing shop?. One old engineer I know showed me invoices from Bearing Services with a routine 70% discount on the NSK bearings.

I cant recall exactly but its in that order..is it 75%...??? i'll need to ask the rep when he next calls in

Originally Posted by eskimo

Its a knocking type noise not unlike tapping your thumb nail against a desk
the knock is in harmony with spindle speed..eg frequency is slower with slow speed and faster with higher speeds. at no load it does'nt happen at very low speeds but starts to becomes noticable above the 700rpm

also comes in with heavy cuts ie the heavier the cut the louder it gets
its definitely in the top spline maybe the top is at the maximum diameter size limit while the spindle it self is at the minimum diameter tolerance.. dont know and that is why I think they should have been getting a matched pair??

Hi Eskimo,
I think I have found the cause your problem, as after running in the new bearing I have the same noise in the top of the spindle at higher speeds also.
After a bit of searching and measuring I found it to be caused from the quill slop. What happens is when you tighten the quill lock it pushes back in the bore at the bottom which in turn makes the quill pivot on the upper quill support ring. It then makes the spindle splines at the top to push forward onto the internal splines of the pulley and thats were the noise comes from.
You can check this yourself by taking off the top cover and putting a dial indicator on the front side of the spindle spline, then lock and unlock the quill lock. If yours is the same as mine it will move forward when the quill lock is done up.
My fix for this will be fitting a cast iron sleeve because mine is out of warranty. I was going to fit it anyway as doing the quill lock up moves the quill enough to put the tram out in the Y axis plain.
Your fix for this is going to be another larger quill, a new matched head quill assembly or another machine
Check yours out as I think you will find it is the problem.
Below is a picture to show what I mean.

Dave

Originally Posted by Dave J

Your fix for this is going to be another larger quill, a new matched head quill assembly or another machine

Ta Dave I think I knew that all along...I mean the later...a new machine

but I will wait and see what happens when Ronmack get back to me..if they do..but as usual I guess I will need to bug them.....

why did yours do it after replacing the bearings?...or had you just not run at higher speeds before to notice it?

larger quill.... or spindle....?

if quill would hard chroming be a possible fix?

Anyone got leads on a decent 4205 ball bearing for a decent price?, I bought a 4205 for about $30 only for it to end up being a chinese made FBJ with about 30% less balls than the original and a few bits of steel in the lubrication when straight out of the packet once washed.

I will ring my local SKF bloke for you Monday, he seems to give me good trade prices.
From RS Online they are $62.10 so I will see what he can do.
RS Mobile

Edit
You would not believe how many different Chinese brands of bearing are in my mill. Even the quill down feed handle bearings where a different brand and needed replacing, they have only done a max 100-200 turns by hand. One had been installed wrong which left ball indentations on the inner race and the other sounded and felt like it had been run for years under power, very poor quality to say the least. After getting it running again with all the new bearing being quit like they should be, I could still hear bearing noises and had to go back and buy motor bearings as well.
I have now replaced every single bearing in the horizontal and the vertical part of the mill with SKF bearings, so they should last years.

Dave

Originally Posted by Dave J

I will ring my local SKF bloke for you Monday, he seems to give me good trade prices.
From RS Online they are $62.10 so I will see what he can do.
RS Mobile

Dave

Thanks Dave, $62 is about what BSC want for them locally at the moment, they run with splash oil so they don't need shields, but if they do have rubber (2RS) I'll remove them.

I did find these but they have no brand, so are probably the same as what you bought.
4205 2RS SHIELDED DOUBLE ROW BALL BEARING 25X52X18MM - eBay, Other Business Industrial, Business, Office Industrial. (end time 30-Sep-10 20:22:42 AEST)

Dave