[MrWild]

I made the mistake of buying a fellow poster's X2 project last winter. He had started doing a Hoss conversion but didn't have a modicum of ability. I had my first clue when I saw the sheet metal screws coming out the front of the control box over an inch long so you impaled yourself if you hit the E-stop button. No big, just change them for some machine screws. Then I found that the axis thrust bearings were "press fit" into the bores so they didn't spin at all. Stripped threads, and misaligned holes too. Finally finishing the Z axis and the "new" nut seemed really loose when I installed it. Christ, it's missing so many balls there could still be some more added to the body and the tube is empty. The sad part is this "Goofin" idiot made sure to take pictures hiding the flaws and never mentioned lost ball bearings or other flaws.

I need to find which bearing house sells loose balls so I can pack the ball nut properly. Now that I see the Z nut is boned, I'm thinking it would be to my benefit to check the X and Y nuts that are already installed.

Thanks in advance

[Al_The_Man]

Did you check local bearing suppliers, most I have found supply individual ball bearings.
Al.

[MrWild]

I'll try that tomorrow. The local bearing house never has things in stock though and their prices....

You are JUST THE MAN I wanted to yak at though. What are the gang plugs called that attach to AMC drive signal pins and where do you get them? I scored a server case that is going to house drives, power, and computer. It's a glorious size and everything will fit. X2 #1 is near done and the silly Yellow Screaming Mimi X2 #2 is next on the boards. I've found that putting things together takes up less room with less chance to break. Having it all in one case is better than several boxes.

[Al_The_Man]

AMC connectors I get from DigiKey what are the pin numbers some are 16p some also have a smaller one for commutation if BLDC?
Al.

[MrWild]

X, Y, Z are 308T Brushed and 16 pins. A axis is brushless. Never made a cable so I'll need a tool too?

[ee_t]

http://www.mcmaster.com/#steel-bearing-balls
http://www.smallparts.com

[Al_The_Man]

If you look up the sheet on the AMC site it will tell you the Molex number, go to the Digikey site and you can order the plugs and pins.
I got the crimper from somewhere like Jameco I believe, it was ridiculously cheap compared to Amp or Molex that are in the $150~$250 price range.
The quality is on par with the high $$ ver also.
Al.

[ZincBoy]

I have replaced the balls in a ball nut on a salvaged ballscrew that had 3 balls total remaining. The balls were sourced from http://www.precisionballs.com/

They have balls sized in less than tenths increments. Depending on your ball screw, you will need to find balls that _exactly_ match the existing ones (and preferably replace all of the balls with the new ones). Mine were 0.092623" in diameter.

I measured the remaining balls with a tenths reading micrometer, but the more accuracy the better. I was under by a few tenths and the re-built screw has about 0.001" of backlash. It should have 0 as it was a pre-loaded P3 class ground screw when new. If you have a spring pre-load, then the size won't be quite as critical. Note that if you go oversize, your nut will lock on the screw and damage both the nut and screw.

Buy a few extra as they tend to go for a wander

[hoss2006]

Roton nuts?
I replaced mine with .1259 balls from ToolSupply, gave them about .001 backlash.

http://stores.ebay.com/ToolSupply_Pl...34Q2ec0Q2em322

http://www.hossmachine.info/forum/ya...Reduction.aspx

Just ordered some .1263's to see if they'll fit at all and maybe get rid of all the backlash.
Hoss

[knudsen]

Roton nuts?

Ouch! (nuts)

[SSN Vet]

Rotons look just like Thomson-Saginaw ball nuts....

Any body know if they are both manufactured at the same facility (i.e. outsorced from China)

I may be looking to replace the balls in my Thomson nuts. I mounted the Z screw last night and they felt like they had just a little play.

Of course, despite my best efforts... "tink, tink, tink", this involved crawling around on the floor with a flash light, and then re-installing the nuts that some how got beyond the stop and spun out the end of the nut.

[Al_The_Man]

Some of the ones I have reloaded have had two ball sizes, the difference is sometimes just a couple of thou, in this case they are loaded alternately.
Al.

[MrWild]

Hey Hoss, how much time do your ballscrews have on them that you're doing oversized balls to? My balls are measuring .1243. I'm thinking on getting .125 and .1259 to play around with. My screws and nuts are new and don't want to run into a lock up problem, but also want as little lash as possible. I need to know how many balls get loaded too. Don't want to over, or under load them.

Never mind, followed the second link.

[knudsen]

My balls are measuring .1243

Seek medical attention.

[MrWild]

Yee-Haw I ordered three sizes from tool supply, .1254, 1259, and .1263. I loaded the nut with .1254 first and didn't like the wiggle the nut was able to move when I cocked it side to side, so I used a combo of 1254 and .1263. I did it with the dissimilar balls because I only ordered 100 of each ($40 delivered) and want to reload the X and Y ball nuts too. The action is very smooth with no tight spots, and has no wiggle waggle when the nut is cocked side to side. The X and Y nuts will be packed with .1259 and .1263 balls as I want those axis to be as close to lash free as possible.

While I'm not real happy paying $40 for 300 balls, I think I'd be less happy having to tear everything apart to hunt down the lash the current setup has with stock balls. X2 #2 will get lash free ballscrews from LinearMotion off eBay. Roton screws and nuts are just too sloppy right out of the box.