spindle bearings

hi my spindle bearings are shot in my Chester Champion Mill the Chinese bearings have lasted 12 years the question is do I fit like for like, the angular bearings 30x55x13.

or do I modify the spindle and fit taper bearings 30x55x17

any suggestion please

ty Kevin

I fitted tapers to my Chester Conquest when I went to a belt drive........

hi John did you have to modify the spindle for the extra 4mm taken up with the taper bearings

Kevin,

the only mod I had to make was ensure the inner races were a tight sliding fit on the spindle to ensure that they could be preloaded.

Hi Kevin

If you do a lot of high speed machining angular contact bearings will run cooler. They are pretty much the "standard" bearing for machining centre spindles. If you do use taper roller bearings check the maximum speed rating for the bearing you select to make sure it is within spec.

The twelve years you got from the Chinese angular contact bearings was a pretty good run. They clearly were able to cope with the loads you imposed on them.

Lubrication is important! Don't be tempted to use plain old automotive wheel bearing grease. Get the manufacturer recommended lubricant for your selected bearings, you may need to sit down when they tell you the price. Maybe you can share the cost with a mate.

Regards
John

John that for that I will keep it standard as it has lasted this long all the best

kevin

OMG I have just jot the cost for my 2 off mill bearings, when I picked myself up from the floor what a rip off from a UK supplier Part No: 7006 Single Row Angular Contact Bearing Brand: NTN or equivalent Quantity: 2 Price each: £75.50 total £151.00.

I called Chester machine tools with no luck all they said was we do not stock or sell them is this the case for Chinese machines'

looked at most UK bearings suppliers and on eBay in the UK they do not stock the size 30x55x13 the US & China have them but are as good as they look

as for my first post do I change to tapper bearing to keep the cost down

thanks Kevin

Kevin

First thing to do is contact Arc Euro Trade and Keiran will help you to decide and will supply the correct bearings,

I have no association with them but have always got good advice and good prices.

Dick

**LINK**

Under £30 each here - and they are precision bearings as well

HTH

Edited By Nigel Barraclough on 17/10/2013 18:12:15

I paid £20 for a pair of quality bearings from a local bearing supplier when I changed them.....Best bet is Arc.....usual disclaimer.... Just a happy bunny

hi Nigel the Bearing boys are not Single Row Angular Contact Bearing I have looked and researched it

thanks Kev

7006-CSUP4 Precision Ball Bearing Single 30mm x 55mm x 13mm

Edited By Nigel Barraclough on 17/10/2013 19:36:09

Kevin,

Funny enough, I will be needing to order one of these for myself.

There are two+ grades. The ones in your mill are standard and not high precision. I will be needing the high precision 7006 for my KX3 mill in our workshop because of CNC higher speed requirement, but still not super high precision.

If you want, give me a call in the morning. I will check for you when I am ordering mine. Also, stick with the angular contact ball bearing. The choice is yours standard or high precision. In your mills case, no special grease necessary. Just don't overload it with the grease.

Ketan at ARC.

Ketan

Sorry meant Ketan not Keiran, age you know!

Dick

thanks for that I have already sent a pm to Ketan

TY Kevin

Hi Keven

VXB Bearings (US) list them for about $14.00 Standard grade
They will also supply high spec if required

I do wonder about using super precision bearings on a conventional mill? OK if you have a temperature controlled high spec mill. that will no doubt be fitted with a cartridge spindle that has been fitted with high spec bearings and then the taper ground in situe before being tested for run out, greased up and certified.

The difference between super precision and commercial grade bearings is only a tenth or two these days, the main thing as mentioned before is that the speed and load rating for the particular bearing chosen is appropriate.

Maybe the cost premium for super precision could be better spent elsewhere?

The will ship anywhere....

I have no connection to them

Regards
John

Edited By John McNamara on 18/10/2013 00:02:43

Hi Kevin

How did you get on with your bearing replacement?

I am in a similar position with my KX3, it took a hard dive into the job and took out the bearings.

Cheers Michael

Interesting debate here. When you say they have lasted for 12 year's, how much work have they actually done in that time, and at what sort of loads? I'm a firm believer in taper roller bearings, you can preload and adjust, but these day's quality doesn't come cheap. However, if you use the machine a lot then the cost is well worth it. The machine is virtually useless if the spindle doesn't run true.

Just follow Ketan's advice, he knows bearings.

Ian S C