[docken87]

Can some one tell me were to find ball screws for a bridgeport mill, model j, would like to get a kit .
thanks for any help.

[morsee]

I used Roton ballscrews and nuts for my Grizzly conversion. While these are rolled screws, I found them excellent and considerably cheaper than any one else. I tried the X axis first just to see how good it would perform. Nice!. My mill is capable of holding within 0.001" on the XY plane. You can catch a video of the mill in operation on YouTube at

[nomedia="http://www.youtube.com/watch?v=xUbPuVLrIDs"]YouTube - grizzlyproject.mpg[/nomedia]

At the point where the video was taken I had not completed the Z axis. I used the Roton ballscrews and nuts, Keling steppers, drivers and power supply, PMDX breakout board and a SmoothStepper signal "conditioner." All works well together. Details are in the video. This was NOT a kit, but it wasn't too difficult to cut out the acme screws and replace them with the ballscrews. Just need to add screw length to compensate for the pair of ball nuts or you won't get the full X or Y travel.

[docken87]

Thanks for the info. I'll check the video. Were did you buy the screws ?
Thanks,
DOCKEN87

[jeffery926]

McMaster Carr sells a bolt in and you do not have to modify anything. Just specify table size, Y axis travel, and the make and model number
of your milling machine. :cheers:

McMaster-Carr

[MaxMekker]

Try to contact guixuan chai [mailto:[email protected]] he wil give you a nice price.
I bought mine directly from him, He is also the same person as Linearmotion2008 on ebay.

[docken87]

Thanks to all for the replys, I should be able to get this project done, the old mill is ready for some update's. It's a 1962 in good condition, we have been using it since 1997. It is used daily.
Thanks,
docken87

[thosj]

Hiwin, too.

http://www.hiwin.com/

I have them in mine, ground, no mod fit in BP clone from 1988. Nice.

[broussard]

I found Bridgeport ballscrew kits at Broussard Enterprises Inc 562-921-4300 ask for jeff

The Ballscrews are Precision Ground to an accuracy grade of C4 class .0005/ft .The ballscrews has a hardening hardness of HRC 58-62 The Ballscrews are 32mm and Are Laser check for accuracy. It is a FSW external nut for a 9 x42 table. Y lengths are 516mm (9” or 12'') X lengths are 1326mm (42”) The Pitch lead is 5.05 and is .200 per revolution a (turn) and the set comes with 1 Yoke, The Price for the ball screw kit is around $825.00 + shipping

[rajhlinux]

Hello broussard.

I hope you still produce them, will be calling you soon for my bridgeport rebuild need Ballscrews are Precision Ground to an accuracy grade of C4 class .0005/ft.

For $825.00 + shipping, every bridgeport owner better upgrade with that price.

Thanks.

[mactec54]

Hello broussard.

I hope you still produce them, will be calling you soon for my bridgeport rebuild need Ballscrews are Precision Ground to an accuracy grade of C4 class .0005/ft.

For $825.00 + shipping, every bridgeport owner better upgrade with that price.

Thanks.

This thread was in 2011, you will have a hard job finding a used set for that price, Rockwell and Hiwin have Bridgeport Ballscrew sets for these machines

This being the better kit as it has the Yoke

https://rockfordballscrew.com/ballsc...idgeport-kits/

[Muzzer]

You can use Chinese ballscrews DFU2505 (so called zero backlash double ballnut) for X and Y. If you do some homework first, the supplier will usually machine the ends to your drawing for a nominal fee. The original yoke on my Taiwanese BP clone needed to be bored out ~1mm or so but that was an easy enough job on the lathe. One drawback of going this route is that the original Y axis ballscrew is a LH thread. There's now very little backlash but now you can feel the springiness in the yoke, end plates, bearings etc - it was presumably there all along. It's a vast improvement over the worn originals.

[mactec54]

You can use Chinese ballscrews DFU2505 (so called zero backlash double ballnut) for X and Y. If you do some homework first, the supplier will usually machine the ends to your drawing for a nominal fee. The original yoke on my Taiwanese BP clone needed to be bored out ~1mm or so but that was an easy enough job on the lathe. One drawback of going this route is that the original Y axis ballscrew is a LH thread. There's now very little backlash but now you can feel the springiness in the yoke, end plates, bearings etc - it was presumably there all along. It's a vast improvement over the worn originals.

No, the springiness is because the standard Yoke is poor and not suitable for Ballscrew use, if you check the Rockford Yoke, it is much more robust, also the Chinese C7 Ballscrews are a poor choice if you want any accuracy with your machine.

[Muzzer]

No, the springiness is because the standard Yoke is poor and not suitable for Ballscrew use, if you check the Rockford Yoke, it is much more robust, also the Chinese C7 Ballscrews are a poor choice if you want any accuracy with your machine.

"No - I agree with you, The springiness is in the yoke" ??