Odd THK linear bearing with missing balls

[synthetiklone]

Hello,
These darn handy linear bearing rails are very hard to come by here in NZ, I managed to spot some odd ones in one of my CNC parts hunting excursions. They were buried inside some type of machine half stripped of other goodies. But..
One of them has a few missing bearings, I know this because I might have been the cause for them to go missing while "playing" opps, popped off end, and scatter on floor go precious 2mm bearings.
After using a magnet to find as many as possible, and filling the little thing up again, and it running on the track very roughly, and opps, popping it off the end again, loosing bearings.....
I measured the bearings, and they're just under 2mm from memory. I have some exactly 2mm ones, which I tried, but it dosent like them, you can feel the 0.03mm larger bearings trying to slide on the undersized track.

There is THK RSR 9 on the side, with some other numbers, (5D01) and on top (A5HIII).. The bearing slide holder unit is 27x20x8mm, and the rails are 5.5x9x195mm, I can find these on THK website.

I went to a local bearing supplier, and he cannot get new bearings, but did offer me a similar THK product (alittle larger) for NZ$1000 for 4x 200mm long units.. price... ouch... ouch again...!

Has anyone heard of these THK's and anyone know how I might be able to get some (6?) odd just under 2mm replacement ball bearings?
I don't really know if I'll end up using them on my 5 axis machine, as they're a bit short, and a bit small I think for the load I'm going to place on them, but they may come in useful for a smaller machine.

Cheers
Tony

[Eduardo Moreira]

You can by individual balls at bearinngs suplpliers.I have done the same to complete one i get from scratch here at Lisbon some time ago.You must supply one ball for measuring.I hope ths help you .Soring my english,and good lack.Regards

[coleong]

Maybe you can forget about the thk linear bearing unless you are requiring high accuracy.

It is better to source those made in taiwan, for a new 15 mm wide rail and 1 meter long with the bearing block cost around 85 US dollar.

[Mat-C]

I know it's a bit late, but in future it's best not to use magnets to pick up the balls... they become magnetised and swarf sticks to them.

[planekrazie]

Are you still looking for the replacement balls? PM me with the size. If they are 3.15mm ( thats by my old calipers ) I have tons. I lost a bunch a few months back and also posted a thread about missing THK balls. I found 2 bearings at work that were not gonna be used anymore. I gutted them and wala. 200 balls. Pm me and Ill send you some if you still need them and they are the same size.
Steve

[RichHagen]

The THK rsr 9 bearing is not that uncommon. You can probably pick up a car with bearings that will ship to New Zealand from Ebay if you have a little patience and keep an eye out for one. THK might have the bearings on their site as well. Rich

[synthetiklone]

Thanks everyone for your help and info, will be in touch..

(I lost this msg thread, and took awhile to find it again, but I'm back! yay).

No company or business here in NZ can help me on these, people in NZ aren't interested at all in selling or finding a few piddly bearings for me. They are only interested in selling me some standard overpriced complete unit which is completely unsuitable.

I'm using these linear rails now in a smaller aluminium and laser-cut-acrylic CNC project.

I measured the bearings with digital linear calipers and they come in at 1.97mm (0.0775 inch) and also measured with a presumably more accurate clamp type caliper at 1.99mm (0.0785 inch) ! (I think the digitals are wrong)

So, I now know for certain that no two rulers measure the same! (as was taught to me many years ago by an older experienced woodworking gentleman. I thought he might have been talking about old wooden rulers, but now I know it even means super accurate metalworking engineering measuring devices!)
It's got me stumped why one measures down to this hundredth scale - thankfully, I'm not planning on making anything this accurate with my CNC machines, although it would be nice to quote such figures.

Anyway, I think the C-type calipers are correct, as they measured 2mm bearings ok, and these 1/100th larger bearings jam alittle in the linear block.

So for my own reference I can almost (but not quite exactly accurately) safely say that they are 1.99mm bearings.

What I've done in the meantime is pull one single bearing from the other sides to pack out the missing 4, and so far seems to be fine. I will see when mounted on the base. Hopefully wont jam up as much as 3 missing in a row.

Iv'e become an expert loader/counter/cleaner of these now. I've now got to find out what sort of lubricant they use, as I've flushed & cleaned them out completely dry with alcohol to remove debris & dust.

Thanks again everyone for all advice & contributions to me & CNCzone

Tony

[ironDigit]

don't forget to demagnetize the bearings b4 reinstalling

i'ld have some heartaches if you came back telling us you need more balls.

demagnetizers can be had at most specialized electronics stores over here and are mostly used to demag screws in electrical components after using a magnetic screwdriver on it.

have fun !!

[ironDigit]

greetings to all DIYérs all over the globe