BB22 Headstock Lathe Bearing

I have a Model BB 22A Cutting Machine manufactured by the Beike Machine Tool Factory of Bengbu Machine Tool Industry Company.

Although my Chinese lathe is working well enough I can feel a little shake on the headstock bearing and I think I may have to change it. The documentation that came with the lathe is pretty minimal but I think the offending item is a 15 x 32 x 9 bearing. Can anyone point me towards any step by step guides for this repair job on this specific lathe? Any youtube videos?

Hello Colin,

I can't help directly, but is this another version of the ubiquitous mini-lathe?

If so, there will be plenty of information,U tube videos and the like on bearing adjustment and changing on those. Even if it is not, that general approach should give you quite a lot of information about how to approach the work on your own lathe.

Regards

Brian

Contact Ketan at Arceurotrade, he knows all about these things.

Richard,

Isn't it being somewhat unreasonable to expect Ketan to provide the information for a lathe model Arc do not sell, even if it is another clone of the mini-lathe; which as yet isn't a known fact? He is very helpful on their own products but for a foreigner-----?

I think it is up to Colin now to follow what may be all he needed to get him started.

Brian

Edited By Brian Wood on 01/01/2018 13:08:41

Brian

My answer was intended to help Colin with his problem, Ketan at Arceurotrade is an expert on Bearings and he sells all types of them, I have had problems with various bearing related problems over the years and Ketan has come up with the answer everytime, As Colin has the measurements of the bearing Arceurotrade should be his first call.

Richard

No it's rather bigger by the look of it (~8 1/2" centre height).

**LINK**

Click the blank and an image will appear.

Neil

Neil,

That's the beastie.

From my manual it has the following specifications ...

height of spindle centre 110mm

max swing diam over bed 220mm

max workpiece diameter over carriage 115mm

max length of workpiece between centres 450mm

max cutting length 420mm

spindle bore 20mm

taper of spindle bore Morse No. 3

I have looked for similar generic Chinese lathes but I seem to have something a little too special.

I guess I'm going to have to bite the bullet, savage a perfectly good allen key to fit in the gap between chuck and headstock, remove the three jaw chuck, and then cautiously go boldly.

Cheers.

.

Neil,

I think you may be confusing 'swing with centre 'height'

MichaelG.

.

.

From your link:

Video of one working.

Looks like a mini-lathe on steroids!

Dave

Hi Colin,

If it is the same lathe as in SOD's link, then it looks like a good heavy kit. I would like to suggest that the headstock bearings are bigger than the specifications you state: 15 x 32 x 9 (6002-zz or 2RS). These bearings are more likely to be some countershaft bearings perhaps or some mistake?

If your spindle has an MT3 taper, then the spindle bearings are likely to have a bore of 30mm or greater.

Does your manual have some kind of exploded parts diagram? Could you take a picture and post it on here?

Have a closer look at where the chuck is mounted. Is it mounted onto a separable backplate or is the chuck mounted directly onto the spindle flange?

Is the chuck an 80mm chuck?

Can you open the side gear box, take a picture of that area and post it here?

If it is a mini-lathe on steroids, then the principles of dismantling should be similar. However, the 6 step speed suggests some kind of belt drive, in place of the hi-low gear arrangement to be found on the original brushed motor mini-lathe.

If it is similar to a mini-lathe, this guide may help you, although the bearings may be a little different, and there may not be a countershaft for high low speed gear change. Also here is the Link to full dismantling of a C3 (not SC3).

Ketan at ARC

Ketan,

Sorry for the tardy response, I can't really offer any excuse except to say I'm retired and refining my procrastination.

Based on your argument it does look as though the headstock bearing I need to replace could be item 46, a 36 x 62 x 14 mm bearing.

The chuck is secured by a series of allen bolts to a round plate that looks to be integral with the shaft drive from the headstock. A second plate is secured by allen bolts to the casing of the headstock.

I'm worried about damaging things when I remove and replace the bearing. To a lessor extent I'm worried about opening it all up and then finding I have the wrong replacement part and having to wait a month while mail order does its stuff in Thailand.

Pictures follow below.

Cheers, Colin

Ketan,

Sorry, typo on my bearing size, it should read 35 x 62 x 14 mm.

The following link is the nearest I can find to a replacement, **LINK**

I'm not looking to save a few pennies here so guidance on a more expensive better quality replacement would be appreciated.

Colin

Hi Colin,

The key bearings appear to be Fig. 46 and 47, which translate as follows:

Russian/Chinese No.46107D = International No.7007A P6 (ABEC 5) - Angular Contact Ball Bearing

Russian/Chinese No.46108D = International No.7008A P6 (ABEC 5) - Angular Contact Ball Bearing

Most bearing dealers outside Russia and China will easily recognise the international numbers. However, what may be tricky will be to find contact angle 'A', with P6 (ABEC 5) precision, where contact angle A = 30 deg., B = 40 deg., and C = 15 deg. (ref.NACHI Bearings).

Generally, 'B' is easily available is general grade, and 'C' is easily available in high precision. For your particular lathe, your max speed is considered to be 'low' when it comes to bearing selection. You will not necessarily need high precision P6 (ABEC 5), if you look for a good Japanese brand from a well known local supplier. So, your choices are for example:

NACHI/NSK or similar Japanese brand : 7007B and 7008B - general purpose Angular Contact Ball Bearings, or

if you want high precision, commonly available are:

NACHI/NSK-RHP : 7007C P4 (ABEC 7), and 7008C P4 (ABEC 7). (Note: P4 is higher precision than P6, but as it is more in production, it can be cheaper than P6)

The high precision bearings are designed for running at high speeds.... much higher than the max speed of your lathe.

I have avoided mentioning SKF, as, unless you buy from an authorised guaranteed SKF dealer, it is very easy to end up paying for fakes. Also, I know that the brands I have suggested above along with other well known Japanese brands are more popular in Asian markets, available at reasonable price.

Also, depending on when your machine was manufactured, and on what machinery the bearings were manufactured, it is often the case that in earlier times, the Chinese 'D' (P6 precision) was similar to current Japanese general purpose precision - P0.

Translations for other bearings in the list are as follows:

1000802 = 61802 also known as 6802 - Deep Groove Ball Bearing

102 = 6002 - Deep Groove Ball Bearing

8104 = 51104 - Thrust Ball Bearing

107E = 6007 P5 (ABEC 3) - Deep Groove Ball Bearing

8101 = 51101 - Thrust Ball Bearing

A word of caution: Only buy the bearings you need after dismantling, because what it says on paper can sometimes be different to what is fitted.

Also, with reference to the Angular Contact Ball Bearings, note the way in which they were fitted - i.e. which way around, before you take then off.

Good Luck,

Ketan at ARC.

Guru Ketan,

Thank you for that carefully worded reply. The technical level you used suits me just fine. MiSUMi Thailand looks to be a convenient local supplier, **LINK** but I will first pull things to pieces as per your advice.

Is there anything I can do to repay your kindness? Anything you need from Thailand? I'll be visisting the UK in a month or so.

Best regards, Colin

Colin,

The link you sent looks good to me. At the end of the day, even if you get a good Chinese brand (e.g. LYC or HRB), or a reputable local Chinese bearing supplier, that will be just as good, as making bearings above 30mm bore requires a factory which has expensive large machinery investment. If you are unsure of the Chinese brand/supplier, or if you don't want to take the risk, stick to the known Japanese brands suggested, which include NACHI, NSK, KOYO

There is no repayment of any kindness necessary. This is a forum where everyone tries to help wherever they can. If you are coming our way, drop in and say hello.

Ketan at ARC.

Colin, are you sure that the chuck isn't screwed onto the spindle, just looking at the photos I immediately thought the lathe was similar to the many 920 types which have screw on chucks. The access for an allen key is fairly limited and would be an unusual fixing from my limited experience. Unfortunately the drawing doesn't help.

John

Ketan,

Thought I'd let you know ...

My son finally chivvied me into stripping down the lathe and replacing the bearings.

The bearings were the sizes you advised.

After reassembling the lathe the headstock shake is reduced but still detectable. This seems to be because there is no way to adjust the preload. I'm now waiting for some bearing shims to arrive.

Thanks again for you assistance.

Colin

Glad to read you are getting there.

Ketan at ARC

Hi Colin et al,

I'm retired now and have added a CNC capability to my RF30 Mill (Rong Fu) and now I'm learning how to use my BB22-1 Lathe properly, which was also mothballed for 25+ years.

But, my problem is I can't find my BB22-1 manual and while hunting the net - I found this thread and have subscribed.

The threading cutting info has worn off my machine and your photos look like they may give me all the ratios I need. But what I'd really like is a copy of the BB22-1 manual if you or anyone else could help, I'd appreciate it.

Kind regards from the "lock down capital of the world

Will Beattie

Victoria, Australia

Will,

It would seem that your lathe is similar, if not identical to mine, another Asian clone. I have a pdf copy of the lathe. I also have made a clarified chart of the change gear table as shown below: (the one in the manual is, shall we say, unclear)

Where Z1 is spindle output, Z2 and Z3 share the intermediate shaft on the banjo and Z4 is the gear on the leadscrew.

PM me your email address if you would like a copy of the manual.

For Colin,

In order to facilitate the removal and replacement of the chuck, I made three mounting screws from new Hex head bolts with threaded collars Loctitied on to them, so that the hex protrudes beyond the rear face of the spindle flange. Thus an ordinary ring spanner can be used instead of the angled, truncated and often lost Allen key can be used. Like this:

John