A question on installing a Ball Slide into a Linear Rail

[avayan]

I am installing an NSK LH20 ball slide carriage into an NSK LH20 linear rail. As I slide the carriage into the rail I notice a few balls popping out of the carriage canals. It is easy to put them back, so I remove the carriage, pop the balls back and try again, only to get a different number of balls to pop out.

Something tells me there is either something I don't know (and chances are the only thing I know here is that I know squat about these rails) or something I am doing wrong.

Even with the balls missing, the rail moves smoothly which makes sense as there is plenty balls left in the canals. Could it be that these slides are built with more than enough balls? If so, why does the number of balls coming out is different every time? I would expect the number to be identical every time as it would be defined by the number of balls driving the available space between the carriage and the rail.

If I just go with the carriage mising a few balls (I was able to get the number of missing balls to 2), will I experience some problems in the future?

Thanks for sharing your sapience on this matter!

[ger21]

Normally their is a plastic spacer the same shape as the rail to hold the balls in place. As you push the block onto the rail, the spacer is pushed out of the end of the block.

I don't think you'll have a problem with only 2 balls missing, but I'm not 100% sure.

You may be able to remove the end of the block after it's on the rail and add the balls from the end?

[cyclestart]

The balls recirculate through the end caps. Are the end caps easy to remove ? If so it should be possible install the balls that way. A few small dabs of heavy grease to keep gravity from doing it's mischief. At least it sounds good in theory If I'm wrong someone will point it out shortly, lots of people using similar rails.
There has to be a way to do this without skipping balls.

[tommylight]

I would not worry for missing 2 balls on a carriage, if not going to exert maximum force on them. They will work perfectly and be precise, no doubt, but try to keep the load under half of what they are rated for just to be on the safe side. Just an advice, have a single ball missing on diagonally opposite groves on the carriage, that way there is the minimal chance that the two groves with missing balls are loaded at the same time.
FYI, i have a carriage missing nearly half of the bearings and still being used on daily basis, but the load on them is minuscule compared to what they are capable ( HiWin HGH 25).
Regards,
Tom