RM1605 Ballnut Tubes ( keep the bearings in place during fitting and transport)

[Jonathan]

rotates smoothly but now an again theres a slight resistance

I think I found some foreign body's in mine when I accidently dismantled it...but I might be thinking of someone else.

just out of interest how many Circuits are there 2 ?

I think it might be 3, RM1610 was 3 - count the number of circular plastic pieces on the ballnuts. Each one of those recirculates the balls to create a circuit. RM2510 has 3...

did you slide the tube onto the fixed or floating end to install ?

do you happen to remember how many balls were in each circuit and were they all the same size ?

Yes they are identical, checked them with micrometer.

i here some ballnuts use a slightly bigger ball everynow and again (anti backlash ball)i could be talking rubbish :)

They sometimes have alternate size balls, like OoOoOoO...this is a good read:

http://machinedesign.com/article/bal...the-myths-0708

i was looking at it wound right out just enough to see one of the Circuits at the floating end to see how i would go about loading the bearings there is a orange plastic seperater at 3 points

Just answered your own question! It's 3 circuits.

when you had the ballnut off did you push them into the inside to remove them and load the balls into each circuit then replace the orange seperator at the end of each circuit as you pushed it onto the tube ?

I tried various methods without much success, so then I just stuck a very big neodymium magnet I had lying around to the ballnut and placed the balls in. The magnet keeps the balls in place perfectly, could even drop it and the balls generally stayed in place...another way is to use grease or something to stick the balls in, but that may not be wise, not sure. I then stuck it in a 50Hz alternating magnetic field for a little while to demagnetise it, probably not necessary but why not...

As for the pitch im not sure they share the same 3.175 ball diameter so i guess it should be the same .

Yes I'd be surprised if they're not.

I think I know where the tube is - but I've just gone back to university. I'll ask my Mum to post it or if not do it this weekend.